Attention-deficit/hyperactivity disorder (ADHD) is one of the most widespread and highly heritable neurodevelopmental disorders affecting children worldwide. Although synaptosomal-associated protein 25 (SNAP-25) is a possible gene hypothesized to be associated with working memory deficits in ADHD, little is known about its specific impact on the hippocampus. The goal of the current study was to determine how variations in ADHD’s SNAP-25 Mnll polymorphism (rs3746544) affect hippocampal functional connectivity (FC).A total of 88 boys between the ages of 7 and 10 years were recruited for the study, including 60 patients with ADHD and 28 healthy controls (HCs). Data from resting-state functional magnetic resonance imaging (rs-fMRI) and clinical information were acquired and assessed. Two single nucleotide polymorphisms (SNP) in the SNAP-25 gene were genotyped, according to which the study’s findings separated ADHD patients into two groups: TT homozygotes (TT = 35) and G-allele carriers (TG = 25).Based on the rs-fMRI data, the FC of the right hippocampus and left frontal gyrus was evaluated using group-based comparisons. The corresponding sensitivities and specificities were assessed. Following comparisons between the patient groups, different hippocampal FCs were identified. When compared to TT patients, children with TG had a lower FC between the right precuneus and the right hippocampus, and a higher FC between the right hippocampus and the left middle frontal gyrus.The fundamental neurological pathways connecting the SNAP-25 Mnll polymorphism with ADHD via the FC of the hippocampus were newly revealed in this study. As a result, the hippocampal FC may further serve as an imaging biomarker for ADHD. One of the most common mental conditions, attention-deficit/hyperactivity disorder (ADHD), affects almost one in 20 children and adolescents globally and is characterized by fundamental symptoms of hyperactivity, impulsivity, and inattention . ADHD isThe hippocampus plays a crucial role in spatial navigation and consolidation of information from short-term to long-term memory . StudiesAs research progresses, increasing attention has been placed on the relevance of genetic factors and their relationship to ADHD, particularly through the application of neuroimaging techniques, such as resting-state functional magnetic resonance imaging (rs-fMRI), structural MRI, and diffusion tensor imaging (DTI). These studies have investigated various gene polymorphisms that could influence brain function, connectivity, and structure related to ADHD. For instance, certain dopaminergic genes, like DAT1 (SLC6A3) and DRD4, have shown significant associations with ADHD . rs-fMRIAnother gene of interest in ADHD neuroimaging is the brain-derived neurotrophic factor (BDNF) gene. Reductions in gray matter volume in prefrontal and limbic structures were associated with the BDNF Val66Met polymorphism, which plays a role in neuronal survival, growth, and differentiation . MoreoveAdditionally, the catechol-O-methyltransferase (COMT) gene has been investigated in the context of ADHD. The COMT Val158Met polymorphism is associated with altered fronto-striatal connectivity , and it Similarly, serotonin-related genes, such as the serotonin transporter (5-HTT) gene and the serotonin 2A receptor (HTR2A) gene, have also been examined, as imbalances in the serotonergic system are thought to contribute to ADHD . A studyFurthermore, the SNAP-25 gene, encoding the SNAP-25 protein, has been shown to play a significant role in the process of synaptic vesicle fusion. This process is crucial for communication between neurons, which in turn is critical for memory and learning . The proWhile there have been some studies investigating hippocampus-related functional connectivity (FC) alterations in ADHD , the relConsequently, the SNAP-25 gene has been shown to play a role in ADHD. In this study, we further investigate its impact by categorizing ADHD patients into subtypes based on their SNAP-25 genotypes. We hypothesize that these genotypic subtypes might exhibit different patterns of functional connectivity, thus providing a more nuanced understanding of ADHD.We expect our findings to provide additional insights into the underlying neurobiological mechanisms linking SNAP-25 gene variations with ADHD symptomatology and working memory deficits. This deeper understanding may not only enhance the accuracy of ADHD diagnosis but also contribute to the development of personalized intervention strategies. For instance, if the effects of the SNAP-25 Mnll variant on hippocampal FC are found to be significant, targeted therapies could be designed to address these changes and improve working memory in children with ADHD.This study recruited 60 children with ADHD aged between 7 and 10 years from Shenzhen Children’s Hospital through a carefully planned collaboration with local schools and pediatric clinics. Our primary goal was to investigate the relationship between hippocampal functional connectivity (FC) alterations and ADHD symptomatology, as well as assess the impact of these alterations on working memory performance in children with ADHD. Prior to enrollment, clinicians at the Shenzhen Children’s Hospital identified potential participants and informed their parents about the research study. All participants and their parents were interviewed by experienced clinicians to confirm or exclude a diagnosis of ADHD or any other psychiatric disorder using a clinical interview and the Schedule for Affective Disorders and Schizophrenia for School-Age Children–present and lifetime version (K-SADS-PL) , based oChildren with ADHD were required to meet the following inclusion criteria: (1) 7–10 years old, (2) educated in private or public schools, and (3) diagnosed with ADHD. Healthy control subjects had the same age and education requirements as ADHD subjects. The exclusion criteria for both groups included a history of head injury with loss of consciousness, severe physical disease or neurological abnormalities, drug or substance misuse, full-scale IQ measured by Wechsler Intelligence Scale for Chinese Children-IV (WISC-IV-Chinese) below 70, prescription medications for ADHD or other medical conditions used over the long term, and comorbid conduct disorder or Oppositional Defiant Disorder (ODD).To better understand the relationship between ADHD symptoms and participant characteristics, we assessed ADHD symptomatology using the Conners’ Parent Rating Scale , which eThe MRI scans were only performed on participants who were right-handed dominant, had no visible abnormalities on their MRI images, and did not have a history of claustrophobia. ADHD participants presented with six or more inattentive symptoms as well as six or more hyperactive/impulsive symptoms, and in subsequent statistical analysis, the summing severity scores of each symptom were used as indicators of symptom severity.As discussed in section “2.3. Genotyping for the detection of SNAP-25 MnII variants” below, we subdivided these ADHD subjects into two subgroups based on their SNAP-25 rs3746544 genotypes, to study the potential correlation between certain genotypes and FC alterations in ADHD symptomatology. The breakdown was as follows:1.TT homozygotes: 35 participants2.G-allele carriers (TG): 25 participantsThe healthy control group did not undergo genotyping, as our study was focused exclusively around ADHD symptomatology and the potential connection to specific genotypes.All children and their parents were informed about the purpose and procedures of the study. Children gave their assent to participate, and their parents provided written informed consent on their behalf. The Shenzhen Children’s Hospital Medical Ethics Committee approved this study. All methods were performed in accordance with relevant guidelines and regulations.Attention-deficit/hyperactivity disorder patients, along with TT homozygotes, G-allele carriers, and HCs, underwent an exhaustive set of cognitive and behavioral evaluations. Parents of the participating children completed the Conners’ Parent Rating Scale . This coCognitive function was evaluated using the Wechsler Intelligence Scale for Children, Fourth Edition- Chinese version (WISC-IV-Chinese) , a globaThese evaluations are crucial to understanding the cognitive and behavioral profiles of our participants. In this study, we employed the original summary scores for each index from the WISC-IV-Chinese and each factor from the Conners’ Parent Rating Scale. Our comprehensive assessments of ADHD symptoms and cognitive functions provide us with a rich dataset that can be correlated with the observed FC alterations in our study. Such correlations may elucidate the clinical implications of the FC alterations we identified and may provide further insights into the symptomatology and cognitive profile associated with ADHD.Following the manufacturer’s guidelines, peripheral venous blood samples were collected from the participants, and SNAP-25 rs3746544 genotyping was carried out using the Flexi Gene DNA Kit . Rs3746544 had a forward primer of 5′ TTCTCCTCCAAATGCTGTCG 3′ and reverse primer of 5′ CCACCGAGGAGAAAATG 3′. EX-Taq polymerase and GC buffer  were used in a thermocycler to perform the polymerase chain reaction (PCR) amplification . A denaturing cycle at 94°C for 2 min was followed by 30 cycles of 94°C for 30 s, 52°C for 30 s, 72°C for 45 s, and finally an extension step at 72°C for 8 min, in the PCR technique. The TT homozygote group had 35 members (TT group = 35), whereas the TG group had 25 G-allele carriers (TG group = 25).We decided to concentrate on the TT homozygotes and the TG G-allele carriers. The distribution of these genotypes in our sample is approximately balanced . This distribution was not designed to reflect population prevalence or vulnerability to ADHD. Instead, it aimed to provide a balanced dataset for comparing functional connectivity patterns.2; slice thickness = 3 mm; no gap. Structure 3D-MPRAGE: T1 Repetition Time  = 2300 ms, Echo Time  = 2.26; Number of Averages = 1.0, Slice Thickness = 1.0 mm, Field of View (FOV) = 256 mm.The Radiology Department of Shenzhen Children’s Hospital in Shenzhen, China, used a 3.0-T system scanner (Siemens Magnetom Skyra) to collect rs-fMRI data from each participant. The following parameters were used in the echo-planar imaging (EPI) process to acquire the rs-fMRI data: repetition time (TR) = 2000∼ms; echo time = 30∼ms; flip angle = 90°; matrix size = 64 \times 64; 32 axial slices; field of view = 24 \times 24 cm1 The image preprocessing in the analysis as follow: the first 10 volumes were dropped because of the instability of the initial magnetic resonance imaging data and the participants’ adaptation to the experimental apparatus. First, the slice time corrected, remaining 230 volumes were realigned to account for the head movement. The head motion criterion of translation <3 mm or rotation <3° in any direction was used to retain all patients with ADHD. Subsequently, the data were normalized and resampled into 3 mm× 3 mm × 3 mm voxels. The time course of each voxel was regressed to remove unwanted factors such as the global signal, white matter signal, cerebrospinal fluid signal, and Friston-24 parameters of head motion. To lessen the impact of low-frequency drift and high-frequency physiological noise, the data were linearly detrended, filtered at 0.01–0.08 Hz, and smoothed with a 6 mm full-width-at-half-maximum Gaussian kernel. The calculation of frame-wise displacement (FD) across the time point for each participant was then performed to evaluate head motion. The bad time point and its 1-back and 2-forward volumes were finally estimated by cubic spline interpolation using scrubbing methods (The DPARSF (v5.1) toolkit  was used methods  at an FDP < 0.6).p < 0.001, cluster-level p < 0.05, and GRF-adjusted. Then, by averaging the Z-scores of each peak coordinate, we identified the functional connectivity signals that revealed distinct variations across the three groups. Brain regions that had undergone numerous compression corrections were subjected to post hoc analysis of two-tailed ANOVA tests to ascertain the direction of FC change between the three. Statistical significance was defined as p < 0.05/4 (Bonferroni’s corrected). Using the Montreal Neurological Institute (MNI) atlas, a standardized and internationally recognized spatial framework, we identified the exact location and boundaries of the hippocampus. We aligned our subjects’ brain images to this atlas, effectively superimposing the predefined hippocampal region onto each subject’s brain image. We then visually confirmed the alignment and made necessary adjustments to ensure an accurate fit. This rigorous process ensured the consistency of our hippocampal ROI across all subjects. To compare the FC maps between the three groups , one-way ANOVA was performed. Age and FD were regressed as covariates. The basic threshold used for the data provided here was voxel-wise p < 0.05 threshold was used as the statistical significance criterion.The FC values that significantly deviated from the baseline were extracted, and partial correlation analysis was used to examine the relationship between the altered FC  and ADHD symptom severity, working memory scores, and Conners’ scale scores. This was done while controlling for nuisance covariates such as age, grade, and mean FD. An uncorrected It is important to note that IQ was not included as a covariate in this analysis. While IQ is often used as a covariate in many neurodevelopmental studies, there are compelling reasons to avoid such an approach. As argued by The feasibility of employing z-variance as a diagnostic biomarker for differentiating patients with ADHD from HCs was evaluated using a support vector machine (SVM) built into the LIBSVM library [LIbrary for Support Vector Machines ]. Based n = 30) and another for testing (n = 30). These groups were randomly selected from our total pool of 60 ADHD patients and were statistically comparable in terms of demographic information and clinical characteristics. As detailed in p > 0.05 for all variables), confirming the comparability of these groups for SVM classification.Our ADHD patient groups utilized in the ROC analysis comprised two genotypes: 35 TT homozygotes and 25 G-allele carriers (TG). For the SVM classification, these ADHD patient groups were split into two: one for training the classifier . This normalization process ensured that features had equal weighting and did not introduce bias to the classification performance.To train the classifier, the normalized averaged ROI values were used. In order to distinguish patients with ADHD from HCs in the independent sample, the averaged z-variance values of the same ROIs were obtained for each participant, normalized, and then input into the classifier as features.p-value.The statistical significance of the classification performance [area under the curve (AUC) of the receiver operating characteristic curves (ROC)] was determined using a non-parametric permutation test. The actual group labels (ADHD and HC) were randomly shuffled in each permutation test trial, and the same classification process was used to determine the classification accuracy score based on the shuffled dataset. This process was repeated 5,000 times to assess the level of statistical significance and obtain the Three TT homozygotes patients were excluded from further analyses due to excessive head motion. The final cohort contained 35 TT homozygotes, 25 G-allele carriers, and 28 HC . No signP < 0.001, cluster P < 0.05/2, controlling for age, grade level, and the mean FD). Significant differences were observed between the three groups in both the left and right hippocampus seeds. Notably, significant differences in FC were found between the right hippocampus seed and right precuneus  for the hippocampus seed regions   (As shown in  = 0.04) . It also = 0.02) . No signReceiver operating characteristic analysis confirmed that HCs and patients with ADHD can be distinguished based on FC between the right hippocampus, right precuneus, and left middle frontal gyrus. As shown in In this study, we built upon our previous research  to invesMemory and spatial navigation are both attributed to the hippocampus. The left and right hippocampi have often been regarded as functionally equal in rats, and this bilateral brain region has been widely researched. Recently, the molecular and morphological properties of the neural connections in the brain hemisphere have been found to exhibit unanticipated asymmetries . SimilarWe found altered FC between the right hippocampus and the (right) precuneus in both the TT and TG patient groups compared to the healthy control group (HCs). Disrupted FC between the left hippocampus and the (left) middle frontal gyrus was observed in patient groups. The precuneus, involved in a wide range of complex tasks such as memory, information integration, mental imagery, and affective reactions to pain, has been extensively reported in correlation with hippocampal FC, especially regarding mild cognitive impairment and Alzheimer’s disease .r = −0.40, p = 0.04). In addition to the previously mentioned findings, our study has further identified a significant negative correlation between altered FC in the left hippocampus and the left middle frontal gyrus in the TT group . This adds another dimension to our understanding of how ADHD may impact brain connectivity and cognitive abilities. It is becoming increasingly clear that genetic variations in ADHD patients play a pivotal role in their brain function, contributing to the symptomatic heterogeneity observed in this disorder. The results underscore the importance of considering the interplay of genetic factors and functional connectivity when examining the complex manifestations of ADHD and its associated cognitive deficits.The left middle frontal gyrus is crucial for literacy development. In Chinese reading, the left middle frontal gyrus serves as a specialized hub region that connects ventral and dorsal pathways . In dyslRegarding the cognitive implications of these FC alterations, the co-occurrence of lower IQ scores and academic achievement deficits and learning problems in ADHD children is well-established. We observed decreased FC values between the left hippocampus and the left middle frontal gyrus in the TT group compared to the TG group, although not statistically significant. Similar findings were reported by These altered hippocampus-precuneus-middle frontal gyrus connections may clarify the compromised attention-related encoding and retrieval processes leading to cognitive deficits in ADHD . A thesiOur first main finding was that FC alterations within the hippocampal FC in Chinese children with ADHD are genetically driven through observations of SNAP-25 variants. If replicated, this result indicates that SNAP-25 is a sensitive marker of disrupted connectivity patterns in ADHD. Although the relationship between SNAP-25 and altered structure or connectivity patterns has been repeatedly reported in patients with bipolar disorder , autism On the other hand, The presynaptic plasma membrane protein SNAP-25 is abundantly and selectively expressed in nerve cells . ConsideHowever, consistent with our findings, SNAP-25 was found to encode a protein that is crucial for synaptic vesicle fusion and neurotransmitter release. Furthermore, recent studies have indicated that SNAP-25 is involved in learning and memory, two processes essential for human cognition and intelligence . Single Although our study does not provide direct clinical applications of SNAP-25 genotyping in ADHD, it suggests the possibility of subtype-specific FC patterns. This might mean that TT homozygotes and G-allele carriers could have differences in ADHD presentation, which could potentially inform future diagnostic and treatment strategies. Further research is necessary to verify these findings and explore their clinical implications in more detail.We acknowledge that our study has several limitations despite providing evidence from many levels. First, the sample size of the fMRI study was rather small; therefore, caution should be exercised when interpreting data. Whole-brain structural and connectivity analyses could potentially be performed using independent samples with a larger sample size. Second, replication of our findings is problematic because of the small number of accessible brain samples. The investigation of SNAP-25 expression levels in various regions depending on the genotype would be of significant interest because of the critical role of the hippocampus in ADHD and the regions that have been demonstrated to be functionally connected. However, changes in the SNAP-25 level and its SNARE complex binding partners have frequently been observed in mouse models and humans with psychiatric illnesses, highlighting the significance of this complex’s control. Moreover, replication from multiple polymorphisms in subjects among genetically different ethnic groups can also reveal significant findings. Even though the analyses took age into account, further evaluations of individuals who had reached adulthood could provide more light on developmental features. Another limitation is that although we examined the relationship between the hippocampus and cognitive deficits, our study did not take into account a more comprehensive psychological assessment of the cognitive parameters associated with ADHD. Therefore, future research can include more features, particularly those related to children’s performance at school or at home. Other patient-specific factors were also reported to limit our study, such as male preponderance, existence of comorbidities, and heterogeneity in clinical presentation, which are typically prevalent in ADHD studies. Therefore, to obtain more accurate results, further research should use more complex patient groups, in which both genetic and symptomatology-based subtypes are considered.MnlI marker of SNAP-25 with ADHD. Based on genotyping for the detection of SNAP-25 MnII variants, we were able to obtain a new subtyping of patient groups (TT and TG) for further application in functional imaging analysis. In other words, instead of adopting the typical symptomatology-based ADHD subtypes, we use genetics-based subtypes, which we believe provides more accurate findings, especially for heritable and genetic disorders such as ADHD. For our FC analysis, we investigated the role of the hippocampal FC in childhood ADHD and its possible association with cognitive impairment. In view of the influence of SNAP-25 on disease processes, an additional thorough integration of genetics-based investigations with neuroimaging is essential to pave the way for larger, more varied, and in-depth genome-wide association studies.A major obstacle in understanding neuropsychiatric illnesses is the functional characterization of disease-associated variants, which will open an avenue for the creation of personalized therapies. According to a growing body of research, the SNARE complex, and more specifically, the SNAP-25 protein, may play a role in mental diseases. Here, as a first step, we were able to corroborate the association of one of the SNAP-25 variants with ADHD by providing modest evidence for the fwen62@126.com) on reasonable request.The datasets generated and/or analyzed during the current study are not publicly available because of Chinese Ethics Committee regulations but are available from the corresponding author (FW, The studies involving human participants were reviewed and approved by the Medical Ethics Committee of the Shenzhen Children’s Hospital. Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.FW, HZ, BY, and AF designed the study. WH, YZ, DF, and LZ collected the data and organized the clinical information. FW, AF, BY, and HZ reviewed the methods. AF, WH, and DF analyzed the data. WH and AF wrote the manuscript. All authors discussed, approved, and proofread the results and the final manuscript.


However, such activation has been tracked primarily within hours of the challenge, rather than sooner, and has been poorly mapped within standardized brain atlases. Here, we report that, within 15 min of receiving 2-deoxy-d-glucose , which can trigger glucoprivic feeding behavior, marked elevations were observed in the numbers of rhombic brain  (RB) neuronal cell profiles immunoreactive for the cellular activation marker(s), phosphorylated p44/42 MAP kinases (phospho-ERK1/2), and that some of these profiles were also catecholaminergic. We mapped their distributions within an open-access rat brain atlas and found that 2-DG-treated rats  displayed greater numbers of phospho-ERK1/2+ neurons in the locus ceruleus  (LC) and the nucleus of solitary tract (>1840) (NTS). Thus, the 2-DG-activation of certain RB neurons is more rapid than perhaps previously realized, engaging neurons that serve multiple functional systems and which are of varying cellular phenotypes. Mapping these populations within standardized brain atlas maps streamlines their targeting and/or comparable mapping in preclinical rodent models of disease.Rodent studies indicate that impaired glucose utilization or hypoglycemia is associated with the cellular activation of neurons in the  Glucose is the essential metabolic fuel source for the brain, with a constant and adequate supply needed for proper function and survival. Iatrogenic hypoglycemia is a formidable clinical problem for patients suffering from diabetes mellitus , and descentral nervous system  )rhombic brain   for each region, from each of the saline- and 2-DG-treated rats, was considered as a representative number of immunoreactive cells. The number of profiles from each brain region was used as a dependent variable, with saline or 2-DG treatment as the independent variable for statistical and exploratory data analyses. A Shapiro–Wilk test 2-DG in rat brain tissues is observed in as little as five minutes following its intravenous administration  profiles immunoreactive for phospho-ERK1/2. A few caveats must be kept in mind regarding the use of this marker to track activation. First, unlike in other systems ,135,218, in Ref. ). Finall in Ref. , could sBrain Maps 4.0, an open-access rat brain atlas that allows for data from multiple labs to be compared with one another. We discuss how our datasets match up with those showing neural connections atlas-mapped to these regions from the hypothalamus or periphery. The new maps furnished in this study constitute an important step towards a standardized global mapping and brain-wide assessment of cellular responses to glycemic challenges, which may allow for more refined clinical or therapeutic interventions for those individuals experiencing complications as a result of iatrogenic hypoglycemia and/or impaired glucose utilization.The results of this study provide new evidence that there are rapidly activating neurons, and perhaps glial elements, that are engaged within 15 min of glycemic challenge in neurons of the LC and NTSm. Some, but not all, of the neurons are catecholaminergic. Importantly, we mapped these neurons to standardized atlas templates from


Urinary incontinence (UI) is a highly prevalent health concern commonly observed during and after pregnancy that can substantially impact women’s physical and psychological well-being and quality of life. Owing to its numerous advantages, mobile health may be a promising solution; however, it is unclear whether the app-based intervention can effectively improve UI symptoms during and after pregnancy.This study aimed to evaluate the effectiveness of the Urinary Incontinence for Women (UIW) app–based intervention for UI symptom improvement among pregnant women in China.Singleton pregnant women without incontinence before pregnancy who were aged ≥18 years and between 24 and 28 weeks of gestation were recruited from a tertiary public hospital in China and were randomly allocated (1:1) to either an experimental group (n=63) or a control group (n=63). The experimental group received the UIW app intervention and oral pelvic floor muscle training (PFMT) instructions, whereas the control group received oral PFMT instructions alone. Neither the participants nor the researchers were blinded to the intervention. The primary outcome was UI severity. The secondary outcomes included quality of life, self-efficacy with PFMT, and knowledge of UI. All data were collected at baseline, 2 months after randomization, and 6 weeks post partum through electronic questionnaires or by checking the electronic medical record system. Data analysis followed the intention-to-treat principle. A linear mixed model was used to examine the intervention effect on primary and secondary outcomes.P<.001; 6 weeks post partum: mean difference −2.68, 95% CI −3.87 to −1.49, P<.001). For the secondary outcomes, a statistically significant intervention effect on the quality of life, self-efficacy, and UI knowledge was found at the 2-month follow-up  and 6 weeks post partum .Participants in the experimental and control groups were comparable at baseline. Of the 126 overall participants, 117 (92.9%) and 103 (81.7%) women completed follow-up visits at 2 months after randomization and 6 weeks after delivery, respectively. A statistically significant difference in UI symptom severity was observed between the experimental group and control group  effectively improved UI symptom severity, quality of life, self-efficacy with PFMT, and knowledge of UI during the late pregnancy and early postnatal periods. Larger multicenter studies with a longer postpartum follow-up are required to further extend these findings.Chinese Clinical Trial Registry ChiCTR1800016171; http://www.chictr.org.cn/showproj.aspx?proj=27455RR2-10.2196/22771 Urinary incontinence (UI), defined as the involuntary leakage of urine , is a prPelvic floor muscle training (PFMT) is the first-line conservative treatment for UI . The latIn recent years, an increasing body of research has demonstrated that mobile health  interventions may benefit health promotion, especially in chronic illness management areas ,25. WithHerein, we developed a Urinary Incontinence for Women (UIW) mobile app for maternal UI self-management . This stThis was a single-center, 2-arm, unblinded pragmatic randomized controlled trial with 1:1 intervention allocation that was reported in line with the CONSORT-eHEALTH  guidelines  35]..35].The study was registered in the Chinese Clinical Trial Registry (ChiCTR1800016171), and the ethical approval was obtained from the Ethics Committees of Shenzhen Hospital, Southern Medical University (NYSZYYEC20190012). The trial protocol has been published, and the findings from an embedded process evaluation will be presented elsewhere .A trained graduate nurse sequentially recruited participants during routine obstetrics clinic visits at Shenzhen Hospital, Southern Medical University, a tertiary level A public hospital in China, between June and October 2020. Eligibility was first assessed by checking the medical records from the obstetrics clinic, after which those who met the eligibility criteria (see the following paragraph) were provided with an information letter describing the study and invited to participate in the study. After providing written informed consent, eligible participants completed a baseline electronic survey at the same time. They were told to contact the researchers via telephone if they experienced any discomfort or pain associated with the PFMT. After completing all follow-ups, participants received compensation with a gift worth RMB ¥100 .The inclusion criteria were as follows: (1) age ≥18 years, (2) having a singleton pregnancy, (3) being at 24 to 28 gestational weeks, (4) being continent before pregnancy, and (5) having a mobile phone with internet access. The exclusion criteria were (1) cognitive impairment and psychiatric conditions, (2) a history of pelvic organ prolapse or pelvic surgery, (3) severe comorbidities found in prenatal examinations that were not suitable for PFMT in pregnancy , and (4) pain during pelvic floor muscle contraction.The trial used a simple randomization approach. A 1:1 random assignment sequence was generated via a table of random numbers by a research assistant who was not involved in the study and was placed into sequentially numbered, opaque, and sealed envelopes. When each participant was enrolled, the intervention manager opened the envelope in sequence, and the participant was assigned to the experimental group, which received oral PFMT instructions and the UIW app intervention, or the control group, which received oral PFMT instructions. Owing to the nature of the app-based intervention and self-reported outcomes, neither the participants nor the research staff were blinded to the intervention.The participants allocated to the experimental group were granted access to the UIW app, which is a mobile app for Chinese pregnant women developed by our research team with technical assistance from the Guangdong Zhuoshang Network Technology Company (registration number: 2019SR1342273). The introduction of the UIW app, including its content and function, can be found in previously published papers [Test versionStage 1: eight test contractions for 1 set of exercises, 3 sets per dayStage 2: eight test contractions+2 strong contractions for 1 set of exercises, 3 sets per dayTraining versionStage 1: eight strong contractions+1 endurance contraction for 1 set of exercises, 3 sets per day; endurance contraction at this stage was 15-second contraction and 5-second relaxationStage 2: ten strong contractions+1 endurance contraction for 1 set of exercises, 3 sets per day; endurance contraction at this stage was 25-second contraction and 5-second relaxation Stage 3: ten strong contractions+1 endurance contraction+5 rapid contractions for 1 set of exercises, 3 sets per day, endurance contraction at this stage was 35-second contraction and 35-second relaxation Stage 4: ten strong contractions+1 endurance contraction+10 strong contraction+5 rapid contractions for 1 set of exercises, 3 sets per day; endurance contraction at this stage was 35-second contraction and 35-second relaxation Both groups received oral PFMT instructions, comprising one-to-one health education about UI and PFMT practice guidance at the time of recruitment by experienced obstetricians, without further follow-up treatments. The health education content covered the following 5 topics: introduction to UI and lifestyle factors associated with UI , which was consistent with the information in the Health Education forum of the UIW app. When teaching PFMT-related skills, pregnant women were directed to lie in the supine position, with the abdomen and buttocks muscles relaxed and selectively contracted and relaxed the muscles around the urethra, vagina, and anus. During this time, PFMT guidance was provided similar to that in stage 1 of the training version in the PFMT program of the UIW app. Obstetricians placed one hand on the abdomen and the other on the perineal body to confirm whether the women had correctly mastered the exercise technique. The general goal of the training was to exercise 3 times a day for at least 2 months.At baseline, participant demographic characteristics and pregnancy-related data, such as age, education, height, prepregnancy weight, number of pregnancies, and prior abortions, were collected through a self-designed electronic questionnaire (by scanning a QR code on the smartphone) before randomization. In addition, delivery information, including gestational age of delivery, birth mode, perineal injury, and neonatal weight, was obtained by checking the electronic medical record system after delivery.All outcomes were measured at baseline, 2 months after randomization, and 6 weeks post partum. The control group completed follow-up assessments electronically (via a QR code linked to questionnaires), whereas the experimental group completed the questionnaires provided in the Online Evaluation forum of the UIW app.The primary outcome was the severity of incontinence symptoms based on the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI-SF) , assesseThe secondary outcomes were quality of life, self-efficacy with PFMT, and knowledge of UI, measured at baseline, 2 months after randomization, and 6 weeks post partum.Quality of life was measured using the Incontinence Impact Questionnaire-7 (IIQ-7), with 7 items assessing 4 domains  . The IIQThe self-efficacy of PFMT was assessed using the 23-item Broome Pelvic Muscle Self-Efficacy Scale, Chinese version, where scores ranged from 0 to 100, with higher scores indicating a higher level of self-efficacy .UI knowledge was assessed using the Chinese version of the Urinary Incontinence Quiz, which is widely used to measure UI-related knowledge. The Urinary Incontinence Quiz is a 15-item validated instrument, with a total score ranging from 0 to 15, with a higher score indicating better UI knowledge .We have made several modifications to the original protocol before trial onset. First, the inclusion criteria were changed to gain additional insight into the preventive effect of the UIW app–based intervention. Therefore, we included all pregnant women regardless of UI status and type of UI, instead of recruiting only pregnant women with stress UI (SUI), as planned at the study onset. In addition, the sample size estimation was changed accordingly. Second, the secondary outcomes were updated. We excluded the assessment of pelvic floor muscle strength  at 6 weeks post partum because of the poor acceptability of pelvic floor muscle surface electromyography among Chinese women at the time of recruitment, a measurement that requires the insertion of a vaginal probe into the vagina. We also replaced the risk factors for UI  with UI-related knowledge . In addition, after trial commencement, although we did our best to follow up as many participants as possible at 3 months and 6 months post partum , the loss rate at 3 months post partum was higher than expected; therefore, outcomes were reported only at 2 months after randomization and 6 weeks post partum. The abovementioned changes were implemented before the data were processed, with no effect on trial implementation.Sample size estimation was performed using G*Power  . As no pt tests and chi-square tests, respectively. Missing values during follow-ups were imputed using multiple imputations [An intention-to-treat approach was used in all data analyses that included all participants. Baseline data are shown as means and SDs for continuous variables and as counts and percentages for categorical variables, with differences in randomization groups assessed using independent sample 2-tailed utations . VariablFor the primary and secondary outcomes, an analysis of a linear mixed model was used to compare the effects of the intervention between groups, accounting for both repeated measures and individual heterogeneity (random effect) . The modAn additional post hoc subgroup analysis was performed using tests for intervention-subgroup interactions to explore whether the primary outcome results differed in subsets of participants grouped by baseline characteristics.P value of <.05 was considered statistically significant.Statistical analyses were performed using R software . A 2-sided P>.05), except that those lost to follow-up were more likely to have lower education levels (P=.01) and higher gestational age of delivery  diagram of the participant flow is shown in  P=.002; .P<.001). Similar results were observed at the 6 weeks postpartum follow-up, and between-group differences in the ICIQ-UI-SF score remained statistically significant . The linear mixed model also indicated that the interactions between the intervention and each follow-up time (at 2 months after randomization and 6 weeks post partum) were statistically significant (P<.001).The results of the primary outcomes are shown in As shown in P=.01; 6 weeks post partum: mean difference −2.19, 95% CI −3.15 to −1.23, P<.001), improved self-efficacy , and knowledge of UI  compared with the control group. For all secondary outcomes, the interactions between the intervention and time remained statistically significant  had statistically significant improvement in UI symptom severity than those with normal prepregnancy BMI (2 months after randomization: P=.01 and 6 weeks post partum: P=.04). Furthermore, among participants with UI during pregnancy, the between-group difference in the intervention effect was significantly lower than among participants with non-UI during pregnancy (2 months after randomization: P=.04 and 6 weeks post partum: P=.02). Moreover, those with a higher baseline ICIQ-UI-SF score had statistically significant improvement in UI symptom severity than those with a lower baseline ICIQ-UI-SF score (2 months after randomization: P=.007 and 6 weeks post partum: P<.001).The post hoc subgroup analyses of the primary outcome revealed statistically significant interactions between subgroups of prepregnancy BMI, UI status during pregnancy, and baseline ICIQ-UI-SF scores, both at 2 months after randomization and 6 weeks post partum -4. ThoseThere were no reported adverse events over the duration of the study.To the best of our knowledge, this is the first trial that combines mHealth and PFMT to prevent and treat UI symptoms in Chinese pregnant women. The results of this study support the effectiveness of UIW app–based interventions in reducing UI symptom severity, UI impact on life, and enhancement of PFMT self-efficacy and UI-related knowledge among pregnant women. This could help to update the Cochrane review to determine the effect of antenatal PFMT as a mixed preventive and therapeutic strategy for UI.Greater improvements in the severity of UI symptoms were observed at 2 months after randomization in the experimental group than in the control group, and the improvement was sustained at 6 weeks post partum. These findings were in line with those of previous studies conducted on community-dwelling women with SUI using app-based treatment programs compared with no treatment . HoweverThe mean between-group differences in symptom severity score reduction  were slightly smaller than those achieved in similar studies using a mobile app for self-management of UI ,48. TherThe sustained improvement in quality during daily life and self-efficacy with PFMT and UI-related knowledge in the experimental group also showed encouraging results. The beneficial effects may be because the UIW app is an evidence-based and multifunctional tool based on behavior change techniques . This mePrevious qualitative interviews also showed that the app could help increase individuals’ confidence in performing PFMT independently and their awareness of UI symptoms ,29. As iThis study has some limitations. First, there were no objective outcome measures. Although the primary outcome evaluation depended on self-reporting, which might have overestimated the improvement of incontinence, it may best represent incontinence from the patient’s perspective, and the self-reported instrument (ICIQ-UI-SF) has been validated previously and widely used in randomized controlled trials ,60. SecoGiven the high incidence of UI during pregnancy and post partum and its severe impact on quality of life, it is critical in clinical practice to provide effective PFMT guidance for pregnant women, which is a crucial component of the primary prevention of UI. This study showed that oral PFMT instructions in conjunction with an app-based PFMT program were more efficient than oral PFMT instructions alone in reducing UI symptom severity and enhancing quality of life in the short term, indicating that the UIW app may be an effective adjunctive tool and could be routinely offered to all pregnant women. However, this was a single-center study, limiting our findings’ generalizability. Therefore, future multicenter studies should be conducted to replicate and extend our findings. In addition, future studies should track study participants for a longer period to provide evidence on whether the effects of the app-based PFMT intervention were sustained.These results demonstrated that the UIW app–based mHealth intervention effectively reduced the severity of UI symptoms during late pregnancy, and the effect was sustained at 6 weeks post partum. In addition, participants receiving the app-based PFMT intervention also revealed higher levels of quality of life, self-efficacy with PFMT, and UI knowledge at follow-up periods. This trial suggested that mHealth interventions might be a promising approach for delivering UI management services among pregnant women.


Anti-glomerular basement membrane (anti-GBM) disease has one of the worst prognoses of nephritis and is rarely associated with other forms of glomerulonephritis. In this report, we present the case of a 76-year-old man who developed anti-GBM disease four months after being diagnosed with IgA nephropathy (IgAN). To our knowledge, although there have been several reports of IgAN combined with anti-GBM disease, there have been no cases in which we were able to confirm that the anti-GBM antibody titer changed from negative to positive over the disease course. This case suggests that even patients with previously diagnosed chronic glomerulonephritis, including IgAN, and an unusually rapid clinical course should be evaluated for the presence of autoantibodies to exclude overlapping autoimmune diseases. Anti-glomerular basement membrane (anti-GBM) disease is a rare autoimmune disease characterized by positive anti-GBM antibodies and linear deposition of IgG along the GBM . Due to A 76-year-old Japanese man with hypertension who had been visiting his local doctor was referred to our hospital in June 2019 because of positive urine protein and occult blood. Urinalysis showed urinary protein 2+ and urinary occult blood 3+, and urinary sediment showed erythrocyte levels of 50-99/high power field (HPF). No red blood cell casts or white blood cell casts were observed. Blood tests showed a creatinine (Cr) level of 0.89 mg/dL (reference range: 0.65 to 1.09 mg/dL) and IgA levels of 450 mg/dL (reference range: 90 to 400 mg/dL). The patient was negative for Complement C3, anti-nuclear antibody (ANA), and ANCA. A renal biopsy was performed in July 2019. Light microscopy revealed 18 glomeruli, including two all-nodular sclerosing glomeruli. Five glomeruli with increased mesangial cells and substrates, as well as one fibrous crescent, were observed , and a second course of PE was administered from the 30th day of the disease. On the 37th day, a blood sample was collected; pancytopenia progressed, and the drug was discontinued based on the suspicion of myelosuppression caused by cyclophosphamide. After the second course of PE, the anti-GBM antibody titer showed a gradual downward trend; therefore, PSL was tapered. From the 60th day, azathioprine 150 mg was added, and PSL was reduced to 20 mg. Thereafter, there were no apparent relapse findings, but renal function did not improve, and he required permanent hemodialysis. The patient was discharged home on the 78th day and remained on maintenance dialysis at our hospital after discharge  50 mg was started on the fifth day as post-treatment. On the eighth day, the anti-GBM antibody was found to be positive at 485.7 U/mL, and a diagnosis of anti-GBM disease was made. Plasma exchange (PE) therapy was initiated and performed seven times during a 14-day course. Hemodialysis was performed simultaneously. The anti-GBM antibody titer improved to 59.6 U/mL, but the patient remained positive for anti-GBM, and a second dose of steroid pulse therapy was administered on the eighth day. The patient was treated with cyclophosphamide; 150 mg was administered from the 19Here, we report a case of anti-GBM disease complicated by IgAN approximately four months after diagnosis. Although several cases of anti-GBM nephritis associated with IgAN have been reported, no case has been reported in which the GBM antibody titer was negative at the time of IgAN diagnosis.The mechanism by which IgAN is complicated by anti-GBM diseases remains unclear. Various hypotheses have been proposed to explain the phenomenon. IgA-associated immune complexes promote immunological and inflammatory events that lead to GBM antigen exposure and anti-GBM antibody production . SecondlIt has been reported that the overall dialysis dependence rate of anti-GBM disease is 69% and that renal prognosis is relatively good (31%) only in patients with IgAN complications . UnfortuThe rarity of this case is that the patient developed anti-GBM nephritis approximately four months after the diagnosis of IgAN. Furthermore, the anti-GBM antibody titer increased from negative to 485.7 U/mL during the four-month period, which was unprecedented. Even if IgAN has been diagnosed in the past, it should not be regarded simply as an acute exacerbation; other factors should also be thoroughly investigated.Herein, we describe a case of IgAN followed by anti-glioblastoma nephritis. When renal function worsened, we first considered IgAN exacerbation. However, this was not the case. Even if the patient has already been diagnosed with chronic glomerulonephritis, including IgAN, autoantibodies should be confirmed again according to the clinical course.


Antigen detection rapid diagnostic tests (Ag-RDTs) used for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein are inexpensive, faster and easy to use alternative of Nucleic Acid Amplification Test (NAAT) for diagnosis of Coronavirus disease 2019 (COVID-19). In this systematic review and meta-analysis, we assessed the diagnostic accuracy of Ag-RDTs in low and middle-income countries (LMICs). We included studies that evaluated the diagnostic accuracy of Ag-RDTs (sensitivity and specificity) against reverse transcription-polymerase chain reaction (RT-PCR) as a reference standard. The study population comprised of people living in LMICs irrespective of age and gender, who had undergone testing for COVID-19. We included peer reviewed prospective or retrospective cohort studies, cross-sectional studies, case control studies, randomized clinical trials (RCTs) as well as non-randomized experimental studies which addressed the review question. A systematic search was conducted in PubMed, CINAHL, Embase, Scopus, and Google Scholar to identify studies published between 1 January, 2020 and 15 August, 2021. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool was used to assess the methodological quality of studies. The analysis was done using Review Manager 5.4 and R software 4.0.2. From the total of 12 diagnostic accuracy studies with 4,817 study participants, pooled sensitivity and specificity were 78.2% and 99.5% respectively. Sensitivity was marginally higher in subgroup analysis based on studies with low risk of bias and applicability concerns (78.9%) and studies using SD Biosensor Ag-RDT (79.4%). However, an inverse relation between cycle threshold (Ct) and sensitivity of Ag-RDT was not seen. The review demonstrated pooled sensitivity value approaching the minimum performance requirement for diagnosis of COVID-19 by WHO with specificity value meeting the specified requirement. Ag-RDTs, therefore have the potential to be used as a screening tool for SARS-CoV-2 detection in low resource settings where RT-PCR might not be readily accessible. However, false negative results need to be interpreted with caution. Althougch, 2020 . AntigenVarious studies are done to evaluate the diagnostic accuracy of Ag-RDTs that vary in study design, study setting and study population along with various brands being evaluated. In a review evaluating the diagnostic accuracy of rapid point-of care antigen test for COVID-19 with studies mainly from Europe and North America, summary sensitivities were from 34.1% and 88.1% for Coris Bioconcept and SD Biosensor STANDARD Q Ag-RDTs respectively whereas overall summary specificity was 99.6% . HoweverWe developed, conducted and reported this review following Preferred reporting items for systematic review and meta-analysis of diagnostic test accuracy studies (PRISMA-DTA) . PRISMA-The eligibility criteria for studies was formulated based on population, intervention, comparator and outcome (PICO) for the review question. We included studies that evaluated the diagnostic accuracy of Ag-RDTs in terms of sensitivity and specificity, against RT-PCR as a reference standard. The study population comprised of people living in LMICs, who had undergone testing for COVID-19. Only original studies in English language published in the year 2020 and up until August 15, 2021 that described their methods and reported enough data for the construction of the standard two-by-two table were included.We included peer reviewed prospective or retrospective cohort studies, cross-sectional studies, case control studies, randomized clinical trials as well as non-randomized experimental studies which addressed the review question. Editorials, letters to the editors, and conference abstracts were excluded since they contained insufficient information required for conducting a review. Studies in which diagnostic accuracy of Ag-RDT was determined in a sample of less than 100 was excluded so that a more reliable estimate of diagnostic accuracy could be obtained.Ag-RDTs are designed to directly detect SARS CoV-2 viral proteins produced by the replicating virus. Most Ag-RDTs for COVID-19 use a sandwich immunodetection method employing a simple-to-use lateral flow test format with techniques such as enzyme-linked immunosorbent assay (ELISA), chromogenic based or fluorescence-based detection. In the case of SARS-CoV-2, Ag-RDTs the target analyte is often the virus’ nucleocapsid protein. After collecting the respiratory specimen and applying it to the test strip, results are read by the operator within 10 to 30 minutes with or without the aid of a reader instrument. Most of the currently manufactured tests require nasal or nasopharyngeal or oropharyngeal swab samples or bronchoalveolar lavage/ endotracheal aspirate , 8. The Sensitivity is the percentage of cases positive by NAAT reference standard that are detected as positive by the Ag-RDTs under evaluation. Specificity is the percentage of cases negative by a NAAT reference standard that are detected as negative by the Ag-RDTs under evaluation .Reverse transcription polymerase chain reaction (RT-PCR) for COVID-19 is a molecular test that detects the genetic material (RNA) of SARS-CoV-2 responsible for coronavirus disease. It combines the laboratory technique of reverse transcription and polymerase chain reaction which amplifies specific complementary DNA (cDNA) targets . TypicalWe conducted a systematic search for relevant articles in the following databases: PubMed, CINAHL, Embase, Scopus, and Google Scholar. The search strategy included keywords like "coronavirus infections", "COVID-19”, "coronavirus disease 2019", "COVID19" "SARS-CoV-2", "covid-19 testing", "Antigen based rapid diagnostic test", "diagnostic test", "lateral flow antigen", "lateral flow antigen detection", "lateral flow assay", "Point of care testing" and a list of all LMICs as listed by the World Bank in 2020 with a combination of Boolean operators . We usedOur review team comprised of four members to search, extract and analyze the available data, perform risk of bias assessment and synthesis of results. Three reviewers SP, AP and DK independently screened and retrieved the studies using the search strategy and from additional sources. Studies were further reviewed for eligibility by screening titles followed by abstracts. Full-text articles of narrowed down abstracts were then be assessed for eligibility. SP and JT rechecked the decisions and upon disagreements, all four reviewers reviewed the inclusion and exclusion criteria and decision for inclusion was made based on majority’s decision. SP made the final decision after thorough reviewing when an agreement could not be reached.Zotero, a research tool to collect, organize, and manage research publications was used to keep a record, and remove duplicates. All studies retrieved from our search strategies matching our PICO questions and inclusion criteria were imported to Zotero. Titles of the studies was first screened followed by abstracts. Screened studies were placed into appropriate subfolders created in Zotero based on decisions to include or exclude. Full text of all eligible studies were retrieved and assessed for eligibility. Final data was extracted from the included studies into an excel spreadsheet. The following information was extracted (if available): demographics details of study participants, total number of study participants, type of study, type of specimen used in Ag-RDTs and outcome measures recorded i.e. sensitivity and specificity. In case of any missing data, authors of the study were contacted for additional information. SP and AP independently extracted the data, and DK and JT checked the extracted data. Upon disagreements, all four reviewers reviewed the final extracted data, and disagreements were resolved through discussion on inclusion and exclusion criteria via majority’s decision.The Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool was used to assess the methodological quality of all studies to be included in this systematic review . QUADAS-2 > 50% indicating substantial heterogeneity) [We extracted data from the studies to construct standard two-by-two table used to calculate sensitivity and specificity. The studies were grouped based on a) clinical presentation at the time of testing i.e. symptomatic, asymptomatic or mixed, b) type of commercial Ag-RDT used i.e. SD Biosensor or tests other than SD Biosensor, c) Ct cut-off value for positive RT-PCR i.e. ≤40, <40, <35, <32 and non-specified, d) risk of bias and concerns regarding applicability for patient selection i.e. low or high, and e) concordance of samples used for index test and reference standard. For subgroup based on commercial Ag-RDT used, tests used in more than two studies were made a separate category (e.g. SD Biosensor) whereas those used in only one study were lumped into a common category of tests other than SD Biosensor. Likewise, subgroup analysis based on Ct cut-off value for positive RT-PCR was done only for studies where the cut-off value used in the study was clearly mentioned. A random effects model with 95% confidence interval (CI) was used to calculate pooled sensitivity and specificity using Review Manager (Revman) 5.4. Higgins’ I square was used to measure heterogeneity (Igeneity) . SubgrouWe identified 3,064 records after performing a systematic search for articles. After removing 732 duplicate records, 2,332 studies underwent title and abstract screening. A total of 2295 studies did not address the review question and were therefore, excluded. Full text screening of remaining 37 studies yielded 12 studies which met the eligibility criteria and were included in the review. Out of the 25 excluded articles, 15 did not involve LMIC study population, four did not report all of the outcomes of interest, two had ineligible index test/reference standard, three had evaluated the diagnostic accuracy of Ag-RDT on a sample of less than 100 and one was not in English. PRISMA flow diagram for selection of studies is depicted in The 12 studies included diagnostic accuracy studies were conducted in Cameroon, China, India, Mexico, Nepal, Serbia, Thailand, and Uganda which enrolled a total of 4,817 study participants. Out of the total 12 studies, 12 of them used consecutive or random sampling method as a method of patient enrollment whereas three of them used non-random method i.e. Pena-Rodriguez et al. . used knRisk of bias on selection of patients was considered low in nine out of 12 included studies as they avoided case-control design, inappropriate exclusions of patients and non-random sampling of patients. Similarly, the included patients matched the review question in all of those studies. In contrast, the remaining three studies had high risk of bias on selection of patients along with high concerns regarding applicability as they used non-random method of patient sampling.With regard to index test, its conduct or interpretation was considered to have low risk of bias in six studies i.e. index test was interpreted without knowledge of the reference standard and a pre-specified threshold was used. However, in remaining five studies sufficient information to clearly judge the risk of bias was not provided. In one study, index test was interpreted with knowledge of the reference standard leading to high risk of bias. Index test, its conduct or interpretation matched the review question in eight studies whereas it was unclear in remaining four studies as sufficient information was not provided regarding whether trained personnel was involved in sample collection and test administration.Since the estimate of test accuracy is made on the assumption that the reference standard is 100% sensitive, RT-PCR alone as a reference standard, its conduct or interpretation was considered to have high risk of bias in all of the included studies as the test lacked the sensitivity of 100%. In contrast, concern regarding applicability was low for all studies except one which used real time micro PCR analyzer as a reference standard.Under flow and timing domain, index test(s) and reference standard were collected at the same time in all of the studies. Similarly, all of the patients received the same reference standard and also were included in the analysis leading to low risk of bias with regard to patient flow. Methodological quality of included studies is presented in Figs A coupled forest plot of sensitivity and specificity with an ascending display of sensitivity values is shown in The overall pooled sensitivity and specificity of 12 Ag-RDTs was 78.2  and 99.5  respectively as demonstrated on Figs 2 = 46% for high risk of bias and high concern regarding applicability). Tables On subgroup analysis, pooled specificity was consistently higher than sensitivity and above 99% except for subgroup defined by Ct cutoff value used for positive RT-PCR (i.e. for Ct <40: 96.9% with 95% CI: 89.3–99.1%). Pooled sensitivity for subgroup analysis based on commercial type of Ag-RDT used was higher for the SD Biosensor test (i.e. 79.4% with 95% CI: 64.2–89.3%) compared to that for tests other than SD Biosensor (i.e.76.3% with 95% CI: 54.7–89.6%). Furthermore, subgroup defined by the clinical presentation at the time of testing had sensitivity ranging from 83.2% (for tests performed on either symptomatic or asymptomatic patients) to 62.9% (for tests performed on only asymptomatic patients). In addition, pooled sensitivity for subgroup based on Ct cut off value for positive RT-PCR was highest when threshold of <40 was used (91.5%) and lowest for threshold of <32 (34.5%). On the contrary, pooled sensitivity for Ct threshold of ≤40 was 69.6%. Surprisingly, pooled sensitivity values for subgroup based on sample concordance for index test and reference standard was higher for studies using different samples (81.1%) than that for those with same sample (77.7%). Pooled sensitivity was higher for tests used in studies with low risk of bias and low concerns regarding applicability for patient selection (78.9%) when compared to that for tests used in studies with high risk of bias and concerns regarding applicability (75.5%). Each of the subgroups estimating sensitivity had higher level of heterogeneity except for the subgroup defined by the risk of bias and concern regarding applicability for patient selection  was found to be 0.972. The HSROC curve is shown in This systematic review and meta-analysis on 12 studies measured the diagnostic accuracy of Ag-RDTs for study population limited to LMICs. Pooled sensitivity from all of the studies (78.2%) was lower than the minimum performance requirement specified by WHO (≥80%) whereas specificity was well above the cut-off of ≥97% (99.5%) , 28. FurThis review was conducted to bridge the research gap with regard to diagnostic accuracy of Ag-RDTs for diagnosis of SARS-CoV-2 in LMIC. Khandker et al. in their review of diagnostic accuracy of rapid antigen test kits reported the sensitivity of rapid antigen test to be higher in population of Europe and America as compared to that in Asia and Africa i.e. low resource settings. The finding was attributed to the repetitive freeze-thaw process during transportation owing to lack of in-situ manufacture of kits in Asia and Africa in most instances . HoweverThe main strength of this study lies in its comprehensive approach to review the available evidence on diagnostic accuracy of Ag-RDTs and provide some of the earliest reported evidence on their diagnostic accuracy with a study population narrowed to people living in LMIC. Furthermore, we only included peer reviewed published articles in the review to avoid skewing of the results by the studies from non-peer reviewed studies. Similarly, we followed rigorous methods for accurate risk of bias assessment along with screening for articles, study selection and data extraction.The main limitations of this review is the methodological quality of the included studies. Three of the twelve studies used non-random method of patient selection whereas Ct threshold for RT-PCR was specified in only six out of 12 studies. Since, Ct threshold is an indirect measure of viral load of the specimen, assessing the diagnostic accuracy without its knowledge limits the comparability of the studies . FurtherDespite the limitations of the study, this review provides a fresh and a unique perspective on diagnostic accuracy of Ag-RDTs in LMICs which has a significant public health implication in regards to the widespread use of Ag-RDTs over RT-PCR for COVID-19 testing. Diagnostic accuracy of Ag-RDTs approaching the near recommended performance requirement specified by WHO provides an evidence based rationale behind the use of Ag-RDT to address the diagnostic challenge for COVID-19 in LMICs. However, further studies to evaluate diagnostic accuracy of Ag-RDT using reference standard with near 100% diagnostic accuracy, achieved via combination of clinical, imaging and laboratory tests, to measure a true disease status, should be conducted to measure the true test accuracy. In addition, diagnostic test accuracy of Ag-RDTs should be evaluated under variable testing conditions i.e. test accuracy using different samples for Ag-RDT, test performed in different days of symptom onset, tests performed in various age groups, etc. The evidence thus generated could be used to evaluate the test accuracy in further detail which could therefore guide clinical use of Ag-RDT as well as direct scientific community to generate testing algorithms for COVID-19 using Ag-RDTs in settings where RT-PCR might not be readily accessible.The review on diagnostic accuracy of Ag-RDTs with studies only from low and middle income countries demonstrated pooled sensitivity value approaching the minimum performance requirement for diagnosis of COVID-19 by WHO with specificity value meeting the specified requirement. Ag-RDTs therefore, have the potential to be used as a screening tool for SARS-CoV-2 detection in low resource settings where RT-PCR might not be readily accessible. However, caution should be exercised over interpretation of negative results owing to the lower sensitivity of Ag-RDTs.S1 File(PDF)Click here for additional data file.S2 File(PDF)Click here for additional data file.S3 File(DOCX)Click here for additional data file.


Syndecan-1 was a significant predictor for the diagnosis of acute HF, expressed by an area under the curve (AUC) of 0.898, similar to NT-proBNP (AUC: 0.976) or cardiac troponin (AUC: 0.839). Moreover, syndecan-1 was independently associated with impaired kidney and liver function at admission, being also a predictor for early, subclinical organ dysfunction in patients with normal biological parameters at admission. When included in the multi-marker model, syndecan-1 levels influenced mortality more significantly than NT-proBNP or troponin. A multivariable regression including syndecan-1, NT-proBNP and troponin provided additional prognostic value compared to each independent biomarker. (4) Conclusions: Syndecan-1 can be considered a promising novel biomarker in acute HF, exhibiting adequate diagnostic and prognostic value. Additionally, syndecan-1 can be used as a surrogate biomarker for non-cardiac organ dysfunction, as its highs levels can accurately reflect early acute kidney and liver injury.(1) Background: Acute heart failure (HF) represents a complex clinical syndrome burdened by increased mortality and a high rate of systemic complications. Although natriuretic peptides  currently represent the diagnostic and prognostic gold standard in acute HF, those molecules do not accurately reflect all the pathophysiological mechanisms involved in the progression of this pathology when determined independently. Therefore, the current paradigm tends to focus on a multi-marker approach for the risk stratification of patients with acute HF. Syndecan-1 is a less studied biomarker in cardiovascular diseases; its assessment in patients with acute HF being potentially able to reflect the myocardial pathological changes, such as fibrosis, inflammation, endothelial dysfunction or global wall stress. (2) Methods: We conducted a single center prospective study that enrolled 173 patients . A complete standardized clinical, echocardiography and laboratory evaluation was performed at admission, including serum samples for the determination of syndecan-1 by the enzyme-linked immunosorbent assay (ELISA) method. (3) Results: The serum concentration of syndecan-1 was significantly higher in patients with acute HF, compared to controls [121.4 (69.3–257.9) vs. 72.1 (41.4–135.8) ng/mL,  Heart failure (HF) represents the “final destination” syndrome for most of the cardiovascular (CV) diseases; its outcome being further burdened by the commonly associated systemic complications. The increasing life expectancy in general population, doubled by modern therapeutic management that is reducing the short-term mortality , determined the so-called HF pandemic, expressing its continuously growing prevalence worldwide ,2.Furthermore, acute HF represents the main cause of hospitalization in the elderly (>65 years old), emerging not only as a considerable source of mortality and morbidity but also as a continuously growing socioeconomic burden. Due to the rapidly unfavorable evolution of the patients presenting with suggestive symptoms for acute HF, it is mandatory to make a rapid and efficient diagnosis, doubled by an adequate risk assessment in order to improve their prognosis and minimize the burden associated with their hospitalization. In this context, it is of paramount importance to search for novel diagnostic tools and risk stratification instruments or, at least, to improve the currently existing ones ,3.According to the World Health Organization (WHO), biomarkers represent molecular parameters that are capable of providing objective and readily available information concerning certain physiological and pathological processes . NatriurSyndecan-1 is a transmembrane proteoglycan, being also a promising candidate for the range of HF biomarkers. Despite the literature data being scarce, there are some studies that evaluated the prognostic and diagnostic potential of this biomarker in patients with HF. Tromp et al., reported a direct correlation between serum syndecan-1 and NT-proBNP, also highlighting a strong relationship between increased syndecan-1 levels and multiple poor prognosis factors in HF, such as low blood pressure, reduced left ventricle ejection fraction (LVEF) and recurrent hospitalizations. When syndecan-1 was included in a composite multi-marker prognostic model, the same authors outlined that it increased the prediction precision, irrespective of the baseline LVEF . The rolMoreover, syndecan-1 contributes to the pathogenesis of ischemic HF, playing an important role in the development of atherosclerosis. Wang et al., observed its overexpression in the macrophages found in atherosclerotic lesions, after the administration of Ang II, also remarking that the Ang II stimulates the shedding of the extracellular domain of syndecan-1. This process makes the ectodomain of syndecan-1 more available for different pro-inflammatory and pro-fibrotic circulating ligands, thus subsequently facilitating the progression of HF . The lisAnother aspect that supports the hypothesis that syndecan-1 is a potentially useful biomarker is related to endothelial dysfunction. Patients with HF are characterized by a markedly increased inflammatory environment, doubled by the exacerbated adrenergic reactivity that is further associated with an important endothelial dysfunction and glycocalyx injury. As syndecan-1 is an important component of the glycocalyx covering the endothelial cells, its serum levels tend to increase in HF patients due to the above-mentioned pathological phenomena. A recent study showed a statistically significant association between the inflammatory status and endothelial injury, syndecan-1 serum levels being linearly correlated with C-reactive protein (CRP). Other highlighted studies increased syndecan-1 levels amongst patients suffering from acute myocardial infarction (AMI), due to both adrenergic stimulation and ischemic-mediated endothelial dysfunction. Furthermore, in these studies the concentration of syndecan-1 increased proportionally to that of adrenaline, both molecules proving to be independent predictors for long-term mortality ,13. WhenThe relationship between kidney disease and heart failure is bidirectional, renal function impairment being also associated with endothelial dysfunction. A recent study showed that syndecan-1 may emerge as an early predictive biomarker for acute kidney injury (AKI) among patients admitted for acute HF. Noteworthy, its serum levels tend to increase in this clinical setting even before the actual onset of kidney dysfunction. Contrary to other biomarkers, which only become elevated once the glomerular filtration rate (GFR) decreases, syndecan-1 increases even in the presence of a continuous glycocalyx damage, as it is the “subclinical” AKI .As previously mentioned, patients with HF are usually older and present a plethora of comorbidities, aspects that actually reflect the systemic continuum between the cardiac and non-cardiac pathologies. Another important characteristic of syndecan-1 is reflected by its major role in the liver diseases, as its serum concentrations tend to increase in those pathologies associated with liver fibrosis. Multiple studies have evaluated the role of this molecule as a potential biomarker for liver dysfunction in non-alcoholic liver disease, chronic viral hepatitis, toxic hepatitis or liver cirrhosis ,12. ContFocusing on its structural characteristics, syndecan-1 is consisting of multiple glycosaminoglycan (GAG) chains that are attached to a core-protein, this molecular architecture being responsible for the specific biologic effects . The corIn this study we aimed to assess the diagnostic and prognostic capacity of syndecan-1 in patients admitted for acute HF. Furthermore, we evaluated the various correlations between the serum levels of this biomarker and other comorbidities (kidney and liver dysfunction) that are associated with a negative prognostic in patients with HF.We conducted a prospective case-control study that included 120 patients who presented to St. Spiridon Emergency County Hospital (Iasi) between January 2021 and June 2021 for sudden-onset (or rapidly progressive) dyspnea. They were subsequently admitted to the Cardiology Clinic for acute HF, irrespective of its clinical phenotype, as described by the latest ESC guidelines . Chronic HF was clinically established according to the Framingham criteria, two major  or one major + two minor criteria  being mandatory for the clinical diagnosis. An echocardiography exam was performed at admission in every patient, using a GE VIVID™ V7  ultrasound device, which assessed the general morphofunctional cardiac characteristics, such as chamber dimension, systolic and diastolic function or pulmonary hypertension, also excluding other secondary causes for the acute decompensation .The control group consisted of 53 patients with previously diagnosed stable HF who presented for regular ambulatory follow-up visits and had no admissions due to HF in the past year.We excluded the patients with acute HF who refused to participate in the study or those who were diagnosed with a severe or end-stage pathology . Another exclusion criteria was a NT-proBNP value below the ESC recommended 300 pg/mL cut-off or the presence of documented neuropsychiatric disorders. Patients who could not be properly examined due to certain individual particularities  were also excluded from the study.All the included patients underwent a complete physical examination, detailed anamnesis and medical history assessment, including comorbidities, relevant laboratory parameters and sociodemographic information. A 12-lead ECG was also recorded early after admission, followed by a complete standard laboratory test panel  for the entire study and control cohort. Classical biomarkers, such as NT-proBNP and high-sensitive cardiac troponin I (hs-TnI) were assessed during the first hour after admission in the Cardiology Clinic.Acute kidney injury (AKI) was defined according to RIFLE criteria, starting with a 1.5-fold increase in serum creatinine, doubled by a 25% decrease in glomerular filtration rate in a patient, with an urinary output lower than 0.5 mL/kg/h for at least 6 h . For AKIA 2 mL sample of venous blood was collected at admission and centrifuged at 2000 rpm for 20 min. The obtained serum samples were adequately stored (−80 °C) until the integrative biomarker analysis of the entire cohort. Syndecan-1′s quantification was performed using ELISA CD 138 ab46506 kits , with a detection rate of 8–256 ng/mL. The absorption readings were made at 450 nm using an Infinite 200 PRO M Plex Microplate Reader . Initially, the samples were diluted and combined with the provided antibody cocktails, according to the protocol indicated by the manufacturer. The quantitative assessment of serum syndecan-1 from each patient was performed with a Magellan Pro v.7.4 software , by intersecting the corresponding reading of each sample on the standard curve.The primary endpoint was to assess the variation and diagnostic value of syndecan-1 in patients with acute HF, compared to the control group with chronic HF. Secondary endpoints consisted in evaluating the role of an increased syndecan-1 as a predictor of systemic dysfunction in the setting of acute HF.p-value < 0.05 represented the threshold for statistical significance.We performed the statistical analysis using the SPSS v.26 software . In all the analyses, a t-test and Whitney-U test served for assessing the differences between variables within the population’s various subgroups. The correlations between the different parameters were assessed by evaluating Pearson’s (for continuous variables) or Spearman’s  r coefficients, as appropriate.We used the Kolmogorov-Smirnov test to assess the normal distribution of continuous variables in the included patients. Mean ± standard deviation (STD) was used to express normally distributed variables, while the not-normally distributed data were expressed as medians with interquartile ranges (IQRs: 25–75%). Frequencies and percentages were used to express descriptive data for categorical variables, while In order to determine the diagnostic performance of the included biomarkers, we compared the areas under the curve (AUC) that resulted from receiver operating characteristic (ROC) analysis. The same analysis was useful in determining relevant diagnostic and prognostic cut-off values for syndecan-1.We conducted this study according to the ethical principles mentioned in the Declaration of Helsinki (revised in 2013). At admission, all patients signed a standard written informed consent in order to participate in the study. The research protocol was validated by the local Ethics Committees of both the University of Medicine and Pharmacy “Gr.T.Popa” , and of the St. Spiridon Emergency Clinical Hospital (no.41/2020).We enrolled 173 patients, further divided into two subgroups: 120 patients admitted in emergency for acute HF, compared to 53 controls with chronic, stable HF, who were evaluated in ambulatory. The overall 30-day mortality rate was 15%, with all 26 fatalities occurring in patients with acute HF, of which 21 (12.1%) deceased during hospitalization.In p < 0.01). However, beta-blockers and renin–angiotensin inhibitors (either angiotensin converting enzyme inhibitors or angiotensin receptor blockers) have been predominantly prescribed in controls as part of the standard therapeutic management of the clinically stable chronic HF.Apart from supportive therapy and inotropic agents , the use of loop diuretics  and mineralocorticoid receptor antagonists  was significantly more common among patients with acute HF  and the onset type of HF   may influence the serum concentration of syndecan-1; the results refuted this hypothesis for both gender  .p < 0.05) in predicting acute HF, only slightly inferior to the gold-standard NTproBNP (AUC = 0.976) but substantially higher than that of hs-troponin (AUC = 0.838)  .p = 0.057], we identified that the concentration of 88.5 ng/mL is 60.8% sensitive and 41.5% specific in predicting increased mortality. This value is below the median value of syndecan-1 from our study group, which is 121 ng/mL.From the ROC curve, we extracted a relevant diagnostic cut-off value of 73 ng/mL, corresponding to the established Youden’s index, which reflects the maximum sum of sensitivity (74.2%) and specificity (50.9%) related to syndecan-1. Regarding the high-risk threshold, at the limit of statistical significance [OR 2.57 (95% CI 0.97–7.01), We found no significant correlation between serum syndecan-1 and the left ventricular end-diastolic diameter (LVEDD) or systolic function of the LV (LVEF). Although we observed a linear increase in syndecan-1 levels with increasing PAPs, it did not reach the statistical significance threshold. However, an elevated serum syndecan-1 was significantly associated with increased LV filling pressures, expressed as E/e’ .As for the prognostic ability or indication of severity of disease expressed in the need of inotrope drugs and ventilatory support, syndecan-1 was significantly correlated with the need for positive inotropic support and with the use of non-invasive ventilation mode. The fatality rate  was not substantially associated with its serum levels. We observed that the increased concentrations of all biomarkers were directly correlated with mortality but only in the case of NT-proBNP in a significant manner .p < 0.01). Not only did the mortality risk follow the rising concentration gradient, but it was more dependent on the particular increase of syndecan-1, compared to the one of NT-proBNP. Basically, the estimated risk was significantly higher in patients in whom syndecan-1 was above the median value, regardless of the intrinsic median concentration of NT-proBNP. A very similar pattern was also observed for the model including hs-troponin, the mortality being influenced exclusively by the variation of the syndecan-1  between syndecan-1 and specific parameters of the liver and kidney dysfunction, aiming to estimate its potential role as a dual biomarker. Accordingly, we found positive and meaningful correlations between elevated syndecan-1 and liver transaminases , a similMoreover, increased syndecan-1 may be used as an early predictor of organ dysfunction, as its elevated serum levels at admission were significantly and directly correlated with increased markers of liver and kidney injury occurring during hospitalization or before discharge, compared to initially normal baseline values .The cardiovascular risk profile includes a mandatory lipid panel assessment in each patient. We considered it appropriate to correlate these metabolic data with serum syndecan-1 levels, thus observing only a substantial negative correlation with HDL-cholesterol levels but not with total cholesterol, serum triglycerides or LDL-cholesterol .Despite the growing awareness among clinicians, researchers and even patients, HF remains one of the main sources of morbidity, mortality and significant healthcare costs in both developing and developed countries . In the Starting from these benchmarks, we initially highlighted the significantly higher concentration of syndecan-1 in patients with acute HF, compared to the control group with chronic HF, a pattern similar to that of one of the few studies that evaluated syndecan-1 in acute HF .p = 0.709).Secondly, regarding the possible discriminative ability of syndecan-1 in predicting acute HF in a heterogenous population, in our study we observed a substantial diagnostic performance exhibited by this novel biomarker, mirrored by its AUC of 0.898, a value similar to that of established biomarkers, such as NT-proBNP and hs-troponin. Moreover, from the ROC curve, we plotted a diagnostic cut-off value of 73 ng/mL, which is lower than the references of 120 or 125 ng/mL, previously reported by Neves , respectp = 0.031) and serum urea . However, the currently available data argue for this association only in patients who developed AKI just prior to admission, with no significant correlations observed in patients with previously diagnosed stable chronic kidney disease [Multiple data are invoking the bidirectional relationship between syndecan-1 and kidney dysfunction ,8; this  disease . In our Under these circumstances, syndecan-1 may also emerge as an adequate biomarker for the early assessment of AKI, especially in patients with acute HF. These data may support the current evidence, which are suggesting that syndecan-1 levels are not influenced by the intrinsic decreased creatinine clearance but rather by the continued damage to the renal endothelial glycocalyx . In patiAnother area of promising research regarding syndecan-1 is its involvement in fibrotic processes, both myocardial and hepatic. We previously highlighted the use of syndecan-1 as a reliable marker of liver fibrosis , given tIn acute HF, glycocalyx degradation may also be induced by neurohormonal hyperactivation of both the sympathetic nervous system and renin-angiotensin-aldosterone system, as an initial compensatory response to the pathophysiological changes  associated with cardiac dysfunction. Consequently, we observed that syndecan-1 was substantially increased in cases with tachycardia at admission (HR > 100/minute), a condition commonly met in patients with HF. Syndecan-1 was also directly correlated with elevated concentrations of the gold-standard NT-proBNP, thus further reflecting the indirect expression of increased myocardial wall stress and neurohormonal activation. This aspect may also be explained by the fact that natriuretic peptides increase endothelial permeability and, implicitly, the release of endothelium-attached molecules, such as syndecan-1 .p = 0.234). Similar results were reported by Tromp et al., who found no significant correlations between CRP and syndecan-1 (p = 0.635) [Inflammatory status is another aggravating factor of endothelial dysfunction, and it is routinely observed in patients with HF . We foun= 0.635) . There a= 0.635) ,30,31; t= 0.635) .Nowadays, the link between dyslipidemia and endothelial dysfunction is widely accepted; the latter is the key step in the initiation and subsequent progression of atherosclerosis. One study previously reported the possible role of syndecan-1 in atherogenesis ; other a2), respectively. These apparently paradoxical data can be interpreted in the key of HF severity. In the terminal stages of this pathology, patients have impaired cardiac output and low blood pressure (possibly requiring inotropes and vasopressors), but also cachexia-through nutrient absorption and metabolism deficit, both of which are classical predictors of poor prognosis [p = 0.024).Two results caught our attention: the significantly higher values of syndecan-1 in hypotensive (BP < 90 mmHg) and non-obese patients , in line with the results reported by Neves et al. (p = 0.520) [p = 0.036) between groups of patients with acute HF divided according to LVEF, elevated syndecan-1 levels being associated with significantly impaired systolic function [Echocardiographic assessment in a patient with acute HF is mandatory and provides important prognostic information. We noted that syndecan-1 levels are not influenced by ventricular systolic function, expressing similar values irrespective of the LVEF (= 0.520) . This asTo summarize, syndecan-1′s solid diagnostic performance in acute HF, similar to the one of classic biomarkers , might open a new perspective concerning the use of novel biomarkers. The interchangeable use of syndecan-1 with the validated biomarkers can be feasible in certain situations, such as acute HF with preserved LVEF, given that syndecan-1 varies independently of this parameter. Another practical situation might refer to a dynamic assessment of syndecan-1 in order to evaluate the response to antifibrotic therapies in HF, such as RAAS inhibitors, thus potentially guiding the therapeutic management. The syndecan-1′s potential use in clinical practice is further based on its preserved ability as an early marker of fibrosis and a direct indicator of endothelial dysfunction in asymptomatic patients, with incipient and subclinical HF. In patients with already diagnosed HF, the potential role as a surrogate biomarker is reasonably supported by its capacity of detecting early, subclinical, liver and kidney injury, even before the alterations of the specific markers of organ dysfunction, such as serum creatinine or liver transaminases, as the negative prognostic role of these comorbidities in HF and vice versa is well-known.The major limitations of the study consisted of the single-center design of the research, with the enrollment of a rather limited number of patients. The COVID-19 pandemic further hampered the total numbers of the cases, due to strict admission protocols and decreased addressability among the patients. Another drawback was represented by the scarcity of the syndecan-1 kits, as only one test was available for each patient, at admission. A further dynamic assessment of the biomarker at discharge and at the follow-up visits would certainly add prognostic value in HF.To the best of our knowledge, this study is the first to evaluate the use of syndecan-1 in patients with acute HF from Eastern Europe, with those promising preliminary results turning the spotlight on this relatively novel biomarker.We focused our research on depicting the potential use of syndecan-1 in clinical practice as a diagnostic and prognostic biomarker in patients presenting with phenomena suggestive of acute HF, especially from the perspective of systemic comorbidities and endothelial dysfunction. Syndecan-1 levels are significantly higher amongst patients with acute HF, compared to controls with stable HF. Moreover, its diagnostic potential is similar to the one of NT-proBNP or hs-troponin, making it a promising surrogate biomarker. Syndecan-1 also exhibited a superior prognostic role when included in a multi-marker test, the mortality rate being more dependent on the variation of syndecan-1 concentration than on that of classical biomarkers.Last, but not least, we emphasize that syndecan-1 is significantly associated with elevated markers of kidney and liver injury, either at admission or during hospitalization.


Criminal legal system data are one source for measuring some types of firearm-related harms, including those that do not necessarily result in injury or death, but measurement can be hampered by imprecise criminal code statutes. We quantified the degree of misclassification in Washington state criminal codes for measuring firearm-related crime.In this study of individuals aged 18 years and older who were convicted of a misdemeanor in Washington Superior Courts from 1/1/2015 through 12/31/2019, we compared firearm-related charges as measured with criminal codes and with manual review of probable cause documents, considered the gold standard. The sample included 5,390 criminal cases. Of these, 77 (1.4%) were firearm-related as measured with criminal codes and 437 (8.1%) were firearm-related as measured via manual record review. In the sample overall, the sensitivity of criminal codes was 17.6% (95% CI 14.2–21.5%), and negative predictive value (NPV) was 93.2% (95% CI 92.5–93.9%). Sensitivity and NPV were higher for cases with exclusively non-violent charges. For all cases and for cases with any violent crime charge, firearm-related crimes described in probable cause documents most often involved explicit verbal threats, firearm possession, and pointing a firearm at or touching a firearm to someone; almost 10% of all cases involved shooting/discharging a firearm. For cases with exclusively non-violent charges, the most common firearm-related crime was unlawful possession.Criminal records can be used for large-scale policy-relevant studies of firearm-related harms, but this study suggests Washington state criminal codes substantially undercount firearm-related crime, especially firearm-related violent crime.The online version contains supplementary material available at 10.1186/s40621-023-00458-1. Inter-personal firearm violence is a significant and growing public health problem in the United States (US). In 2021, 20,958 Americans died from firearm homicide, reflecting the highest rate since the mid-1990’s and an almost 45% increase from 2019  . Indeed, researchers using criminal records have previously combined violent The objective of this retrospective observational study was to quantify the degree of misclassification of firearm-related violent crime with Washington state criminal codes, using manual record review as a gold-standard. Understanding the degree of misclassification bias in criminal codes can inform more rigorous research and development of new coding systems designed to better estimate the true burden of violent firearm-related crime in Washington.This was a secondary analysis of data used in a larger cohort study of risk of subsequent firearm-related violent crime associated with downgraded misdemeanor convictions  .Data on criminal charges and convictions were provided by the Washington Administrative Offices of the Courts (AOC) and King County Department of Judicial Administration (KCDJA) and are available to qualified researchers upon request to AOC and KCDJA.Violent crimes were measured with the Revised Code of Washington (RCW) criminal codes. The RCW is a collection of Washington state statutes, including criminal statutes, in which the legislature has identified specific behaviors as criminal. In turn, the statutes classify and organize the nature of an alleged criminal action as a specific type of criminal charge, which prosecutors use as a guide to determine what crimes a defendant will be charged with under the RCW. We created two definitions of violent crime using RCW codes  used an inductive process to thematically code each case based on the probable cause narratives into non-mutually exclusive categories for descriptive purposes. Categories were refined during the coding process, and questions were discussed during team meetings. See Additional file We compared classifications of firearm-related crime based on criminal codes and manual record review after restricting our sample to cases in which we had complete data on firearm-related crime from both sources (excluding 155 cases in which affidavits of probable cause were unavailable). While we had information on criminal charges and convictions, we focused on RCW codes recorded in criminal charges rather than convictions since convictions may not correspond well to affidavits of probable cause for reasons other than misclassification, e.g., because of judge or jury decision making and other criminal legal system processes such as plea bargaining.We calculated overall and violent crime-stratified measures of sensitivity and negative predictive value (NPV) by constructing a 2 × 2 validation table, cross-classifying cases according to the two measurement sources . We also described the frequency of firearm-related crime types per our thematic coding.We used Research Electronic Data Capture (RedCap), hosted at the Institute of Translational Health Sciences (ITHS)  were firearm-related as measured with criminal codes and 437 (8.1%) were firearm-related as measured via manual record review  for non-violent crime. Depending on the source used, the percentage of alleged crimes in our sample that were firearm-related ranged from 1.4 to 8.1%, and the percentage of alleged violent crimes that were firearm-related ranged from 0 to 13.6%, depending on the specific definition/sub-categories of violence used. Approximately 7–8% of all violent victimizations reported in the National Crime Victimization Survey in 2018–2019 involved a firearm, similar to our estimates based on manual review and much higher than our estimates based on criminal codes  but may also be used in reference to non-firearm guns. However, we did not code cases as firearm-related if the evidence clearly suggested the crime involved a non-firearm gun , consistent with Washington state law, RCW 9.41.010(12). We were missing 155 records. Affidavits of probable cause might differ from formal criminal charges for reasons other than measurement error , so our estimates of sensitivity likely reflect a lower bound. Additionally, as mentioned above, sensitivity may be affected if our sample disproportionately over- or under-included those with criminal code-measured firearm-related charges. However, the proportion of firearm-related charges measured with criminal codes did not differ between the overall population (1.5%) and the population sampled based on downgraded convictions (1.4%). Therefore, the marginal distribution of firearm-related crimes measured via manual record review should not differ from the target population, and our estimates of sensitivity will be approximately valid (Fox et al. Criminal records can be used to conduct large-scale policy-relevant studies of firearm-related harms, but our results suggest that Washington state criminal codes substantially undercount firearm-related crime as reflected in criminal charges, especially firearm-related violent crime. This study can be used to inform quantitative bias analyses of firearm-related crime, novel approaches to firearm-related crime identification, and motivate modifications of state criminal coding systems.Additional file 1. Suplementary methodological information and results.