Health literacy (HL) plays a key role in explaining health disparities. School nurses (SN) provide health related expertise within the school setting. A positive effect on the HL of children but also their teachers and parents has been suggested by some research, but gaps persist in the available information. As a pilot project, SN, which are not common in German schools, were placed in 28 public elementary and secondary schools in two German states. Children , parents (n = 3978) and teachers (n = 420) participated in a 2017 baseline (T0) survey. Data collection was repeated in 2018 (T1). HL was measured using the Health Literacy for School-Aged Children scale (HLSAC) (children) and the European Health Literacy Short Scale (HLS-EU-Q16) (adults). Descriptive and multivariate data analyses were carried out. The HL of all groups increased between T0 and T1. Low child HL decreased from 17.9% to 14.9%. Problematic and inadequate HL dropped from 43.8% to 38.8% among parents and from 49.9% to 45.8% among teachers. Improvements were significant for children and parents but not for the teachers. Despite the relatively short intervention period and a relatively non-specific spectrum of interventions, there is some evidence that SN may contribute to strengthening HL within the school setting. The longer-term effects of SN on health literacy and child health should be further examined. For this, a clearer conceptualization of the scope of work of the SN in Germany including their educational interventions is imperative. Health literacy, understood as the “people’s knowledge, motivation and competences to access, understand, appraise, and apply health information in order to make judgments and decisions in everyday life concerning healthcare, disease prevention and health promotion to maintain or improve quality of life during the life course” , plays aEfforts to improve health literacy are likely to have a greater impact if they start early, ideally while children and adolescents are developing their own health-related concepts and behaviors ,9. The aNational Action Plans in numerous countries recommend focusing on public schools as an ideal setting to enhance health literacy early in the lifespan ,13,14, iSometimes teachers themselves show a limited level of health literacy and they may be uncertain how to support vulnerable children in their care such as chronically ill or disabled students ,18. ThesInternationally, school nurses work in public schools to provide health education, surveillance, and clinical services and to participate in setting-oriented public health and health promotion programs ,21. SpecEffective school nurses are highly trained professionals. They have a wide range of clinical, social, and educative competencies, combine nursing expertise, trustworthiness, presence and discretion, and can act as an advocate for children’s health concerns ,21,26. CIn their systematic review, Wainwright et al. concluded that the focus of research activities on school nurses tends to be either broad and role orientated or limited to specific aspects . StudiesIn Germany, there are hardly any structures for school nursing and very few school nurses work in the country. The few that do are almost always employed by private  schools. To date, there is no standardized university-based training program for school or public health nurses in Germany. To potentially address this situation, a pilot project was carried out in the German federal states of Hessen (former West Germany) and Brandenburg (former East Germany). Adult and pediatric nurses, most of them with a traditional vocational training and some with years of clinical expertise, participated in an intensive three months education program followed by on-the job training while working as school nurses in 28 primary and secondary schools. During the intervention period, the school nurses provided health care for acute health problems and first aid, engaged in health promotion and prevention activities, supported students with chronic conditions and disabilities, and provided counseling and moderation . While tThe pilot project was evaluated from 2016 to 2018 by the authors of this article using a comprehensive mixed-methods study design odels for the assessment of the impact of school nursing on health outcomes and determinants of health require development” . Based o


A number of studies have investigated the effects of individual foods and/or nutrients on rheumatoid arthritis (RA), but research focusing on whole dietary patterns remains limited. The association of dietary patterns and rheumatoid arthritis is therefore not well elucidated. This study aims to determine existing relationships between major identified dietary patterns and RA.This matched case–control study was conducted on 297 individuals in Isfahan, Iran. The presence of RA was determined by an expert rheumatologist, based on the American College of Rheumatology definitions, 2010. A 168-item questionnaire was used to collect dietary data. Major dietary patterns were identified using the factor analysis method.P < 0.001). The association remained significant even after taking other confounders into account . A positively significant association was also observed between adherence to western dietary pattern and RA in the fully-adjusted final model .Two major dietary patterns, namely, healthy and western dietary patterns, were identified. Lower adherence to the healthy dietary pattern was associated with increased risk of RA (OR = 2.80; 95% CI 1.74–4.67; The study suggests that there is an inverse association between adherence to a healthy dietary pattern and the odds of RA, and a positive significant relationship was found between western dietary pattern and RA. Further studies are required to confirm these findings. Rheumatoid arthritis (RA) is a systemic autoimmune disease with effects on synovial membranes and joints as a result of inflammation. It leads to joints damage, muscle erosion, atrophy, and pain, and can also impair physical function –3. The pBoth inherited and environmental variables are involved in the etiology of RA, although the main cause of RA has not been clearly elucidated. Several environmental factors may contribute to the etiology of RA, including unhealthy lifestyle choices, dietary risk factors, smoking, and infection .Dietary intake is considered as a modifiable risk factor associated with RA, perhaps through mediating systemic inflammation. A number of studies have shown that higher consumption of protein and red meat, as well as lower intakes of vegetables, olive oil and vitamins, increased the risk of inflammatory polyarthritis or RA –14. SeveIn this matched case–control study, 297 participants  aged 19–69, were recruited in Isfahan, Iran. Each patient was paired with 2 healthy controls by gender. 100 patients newly diagnosed with RA were selected by an available-sampling methodology from Sepahan Clinic in Isfahan. RA diagnosis was made by a rheumatologist, based on the American College of Rheumatology 2010 classification criteria. RA onset was defined as the day of diagnosis, as stated in participant medical records. RA cases with a maximum of 1 year since diagnosis were included. In addition, 197 healthy subjects were randomly selected from the same clinic. Subjects were not included in the study if they had any history of chronic diseases, such as cardiovascular diseases, renal disease, liver diseases, or cancer, if they were on any specific diets or food prohibition schedules, or consumed alcohol. Participants with incomplete food frequency questionnaire (FFQ) were excluded, who answered less than 35 items of the FFQ. Those with unacceptable FFQ responses  were also excluded . All parDietary information was obtained using a validated 168-item semi-quantitative food frequency questionnaire (FFQ) . For eacAnthropometric measurements were obtained based on standard methods. Weight was measured by a digital scale, to an accuracy of 100 g, with participants wearing light indoor clothing and bare feet. Height was measured using a tape meter, with participants standing without shoes. Body mass index (BMI) was calculated as weight (in kilograms) divided by the square of the height (in meters).Demographic information was gathered through a self-administered questionnaire. The socioeconomic status (SES) of study participants was assessed using a self-reported questionnaire. Data included: education level of the participant and the head of their family ; employment status of the participant and the head of their family (yes/no); family size (≤ 4/ > 4); and housing status (owner/tenant) and type (apartment/villa). Demographic characteristics were obtained by a general self-reported questionnaire. These included: disease and drug history, medical history, and special diet and/or food prohibitions.For all statistical analyses, SPSS  was used. Quantitative data were presented as mean and standard deviation, while qualitative variables were presented as frequency (numbers and percentages). To check the normality of the quantitative variables, the Kolmogorov–Smirnov test was used. KMO and Bartlett's Tests were applied to evaluate the adequacy of sample size and the applicability of the factor analysis method. Dietary patterns were derived using Principal Component Analysis (PCA) based on 168 food items. The individual items were classified into 32 predetermined different categories, based on similarity in nutrients. A scree diagram was used to determine the number of factors (dietary pattern) with an eigenvalue of > 0.2. Varimax rotation was applied on extracted factors (dietary patterns) in order to review correlations between variables and factors. The factor score for each dietary pattern was calculated by multiplying the number of nutrients by the pattern in the estimation of parameter; then each participant received a factor score for each specific pattern. All participants were categorized according to the median values of the dietary pattern scores.t-test or chi-square test was applied, based on nature of the data. In addition, a one-way analysis of variance (one-way ANOVA) and chi-square test were used to compare means of quantitative and qualitative variables between the medians of each dietary pattern, respectively. Multivariable logistic regression was carried out to study the associations of dietary patterns with the odds of RA. First, in the crude model, the risk of RA was calculated between the medians of the identified dietary patterns. Then in the adjusted models, the following relationships were calculated: in Model I, adjustments were made for sex , BMI (kg/m2) and age (year). Model II additionally adjusted for disease history and lifestyle variables, including drug use, education, smoking (yes/no), physical activity (MET_min/wk), and socioeconomic status . Model III additionally adjusted for energy intake , and macronutrients. The significance level was considered to be 0.05 in this study.To compare variables between cases and controls, independent samples The two major dietary patterns identified were: Healthy Dietary Pattern ; and Western Dietary Pattern . These patterns were revealed by factor analysis, as presented in Table P < 0.001 for all). SES, as well as education, were significantly lower than those in the control group.The characteristics of participants in the case and control groups are presented in Table The characteristics of the study participants across the dietary pattern median scores are presented in Table P < 0.001). When the model was controlled for age, BMI and sex, the association remained significant . Furthermore, after adding disease history, drug use, education, smoking, physical activity, and socioeconomic status in Model II  the association remained significant. Also, after taking other confounders into account in Model III, the association still remained robust . No statistically significant association was seen between western dietary pattern score and RA risk in the crude model . However, after adjustment for age, sex and BMI in Model I, and after adding disease history, drug use, education, smoking, physical activity, and socioeconomic status in Model II, the association between western dietary pattern and RA altered, becoming a marginally significant association: Model I ; Model II . In the final fully adjusted Model III, a positively significant relationship was found between western dietary pattern and RA .Multivariable adjusted OR for RA across the median values of the main dietary pattern scores are presented in Table In this case–control study, two major dietary patterns were identified: healthy dietary pattern and western dietary pattern. According to the results, those with lower adherence to healthy dietary pattern had a higher risk of RA. However, the western dietary pattern was positively associated with the disease. Limited data is available regarding broad dietary patterns and their relationships to RA in Asiatic and especially Iranian populations, so the present findings can help develop a better understanding of the relationship between diet and this chronic disease.RA has an adverse influence on patients’ abilities to perform normal daily activities, and can reduce both employment opportunities and quality of life. RA imposes substantial economic burdens on individuals and societies , 22. In Also fruits, dried fruits, and vegetables are major components in a healthy diet. Several studies have shown the protective effects of fruit and vegetable consumption on RA , 25. FruThe intake of low-fat milk and dairy products has also been shown to decrease the risk of RA. A possible mechanism of this effect may be attributed to the micronutrients in milk, such as riboflavin, calcium, and vitamin B12, and also to the immunomodulating effects of vitamin D .Previous studies have shown that foods and diets perhaps play a role in the cause of RA through altering systemic inflammation and immune-inflammatory responses . It has A number of studies have suggested that high levels of red meat consumption are a risk factor for the development of inflammatory polyarthritis and RA , 35. MeaThe human body needs a healthy balance of the n-6/n-3 ratio. Excess consumption of omega-6 s can influence the function of adipose tissue and promote the production of pro-inflammatory chemicals , 36–38. In contrast, some studies have reported no significant association between diet and RA . These cThis study has many strengths. Newly diagnosed patients were selected to reduce the likelihood of post-diagnostic dietary changes. The effects of several potential confounders were controlled for in the statistical analyses. Using principal component analysis can lead to increased power in detecting diet-disorder associations by creating continuous variables. However, the present study also possesses a number of limitations, including a relatively small sample size, and the evaluation of dietary patterns using a self-reported 1-year FFQ (which may increase the possibility of errors in measuring dietary intake). It is possible that patients had changed their diets after RA diagnosis, thus the present findings may not reflect the accurate relation between diet and RA risk. To limit this potential for inaccuracy, cases were recruited from newly diagnosed patients in order to collect food intake data before extensive modifications to habitual dietary patterns. In addition, some of the variables measured were different between cases and controls across the dietary patterns, which might have influenced the findings. However, this problem was tackled by adjusting these variables to mitigate them. Also, some potential confounders were not assessed, such as stress level and genetic factors, which might have influenced the results.The present study suggests that healthy dietary pattern is associated with a reduced likelihood of RA, and the western dietary pattern appears to be associated with increased odds of RA among Iranians.This presents new insights with regard to dietary control and managing RA risk. However, more studies are required in this area to confirm the present findings.


Chinese medicine Sangbaipi decoction is extensively applied to the therapy of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in China. However, owing to the low quality, small sample size, and methodological heterogeneity of these studies, this conclusion is not convincing. Consequently, it is necessary to systematically evaluate the clinical efficacy and safety of Sangbaipi Decoction in the treatment of AECOPD patients, and provide high-quality evidence for its clinical application.We will follow the preferred reporting items for systematic review and meta-analysis (PRISMA) for reporting the results of the review in this study. We will utilize the Review Manage software V5.3.0  to assess the risk of bias and visualize the results. We will use Stata software  to perform the meta-analysis.This study is a systematic review and meta-analysis protocol of Sangbaipi decoction on AECOPD, participants were not recruited and data were not collected from participants, so ethical ratification is not required.This study will provide high-quality synthesis of the effectiveness and safety of Sangbaipi decoction for AECOPD. Upon completion, the results will be submitted to a peer-reviewed journal.The efficacy and safety assessment of Sangbaipi decoction for AECOPD will be supported by this protocol.PROSPERO CRD 42019138405. Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is defined as an acute worsening of respiratory symptoms that result in additional therapy, which is a serious event in the management of COPD. Therefore, AECOPD remains the subject of vigorous study.Chronic obstructive pulmonary disease (COPD) describes a predominantly smoking-induced small airway and/or emphysematous disease associated with airflow limitation. The application of glucocorticoids can benefit patients, but many studies have shown that glucocorticoids are not effective in the treatment of COPD and the development of airway inflammation, which also cannot reverse the decline in lung function. There is a phenomenon of glucocorticoid insensitivity in AECOPD. Therefore, the clinical efficacy of AECOPD needs to be improved.At present, the conventional Western medicine treatment options for AECOPD include anti-infection, anti-inflammatory and anti-asthmatic, bronchial expansion, and mechanical ventilation therapy. but there are some limitations, such as single reports, scattered research, small sample size. With the development of evidence-based medicine, it has opened up new research fields in the clinical efficacy evaluation of Chinese medicine, produced new research ideas and methods, and promoted the progress of clinical research in Chinese medicine.,7 Therefore, to systematically review the efficacy and safety of Sangbaipi decoction in treating AECOPD may provide higher quality evidence for further clinical application.In recent years, clinical studies have also shown that Sangbaipi Decoction combined with conventional Western medicine treatment of AECOPD can improve the clinical efficacy,22.1 We have registered this plan in the International prospective register of systematic reviews (PROSPERO) and the number is CRD 42019138405. If there are any adjustments throughout the study, we will fix and update the details in the final report.The preferred reporting items for systematic review and meta-analysis (PRISMA) for reporting the results of the review will be followed by this research.2.2We will use the PICOS (participant-intervention-comparative-outcome-study design) framework for the eligibility criteria of our review as Table 2.3We will search each database from the built-in until August 2020. The English literature searches PubMed, Cochrane Library, EMBASE, and Web of Science, while the Chinese literature comes from CNKI, SinoMed, VIP, and Wangfang database. What is more, targeted grey literature searches will be conducted against the Clinical trials.gov and the international Clinical trial registration platform retrieval portal to identify ongoing and completed trials. In all database searches, there will be no restrictions on languages. However, once the search has been conducted, papers that are not in English or Chinese will be excluded. The search strategy of PubMed is as Table 2.4We will manage the electronic citations downloaded from 8 databases, then they will be imported into EndNote X7.0. Once duplicates have been removed, 2 reviewers will retrieve all the literature independently. The reviewers will screen titles and abstracts, excluding nonrelevant papers according to the inclusion/exclusion criteria. If there is any disagreement in the process of document inclusion, it will be decided through discussion. We will use Microsoft Excel 2019 to collect relevant information and extract data from it. The extracted information will be classified into 5 parts as Table 2.5 Two review authors will evaluate the original design independently. Bias risk through 7 assessment trials: random sequence generation (selection bias), allocation concealment (selection bias), blinding of participants and personnel (performance bias), blinding of outcome assessment (detection bias), incomplete outcome data (attrition bias), selective reporting (reporting bias), and other bias. Each item is classified as “Low risk", “High risk” or “Unclear risk”, and the percentages for each category in each source of bias analyzed will be described by RveMan 5.3.0 software and the results interpreted taking the risk of bias into account. The disagreement of bias risk will be resolved through further discussion with a third independent reviewer. Sensitivity analysis will also be conducted to exclude the studies reporting the high risk of bias in any domain analyzed. We will future assess the certainty of the evidence of the primary outcome through the “grading of recommendations assessment, development, and evaluation” (GRADE) system. Based on 5 areas , the quality of evidence is divided into one of 4 levels: high, medium, low, and very low. The GRADE profiler 3.2 will be employed for analysis.All the included studies will be evaluated in accordance with the Risk of Bias Tool of guidelines of the Cochrane Handbook for Systematic Reviews of interventions.2.6X2 test, and the degree of heterogeneity will be determined by the I2 values (I2 > 50% or not) or P value (P < .05 or not). If I2 < 50% and P > .05, the meta-analysis will be performed using the Mantel–Haenszel fixed-model. If I2 ≥ 50% and P < .05, we will use random-effects models for the meta-analysis. We will use subgroup, meta regression analyses, and sensitivity analyses to explore the sources of heterogeneity. If the source of heterogeneity cannot be known, the synthetic analysis will be abandoned and descriptive analysis will be adopted. Descriptive statistical analysis will be performed on adverse reactions. For indicators with a number of studies ≥10, we will draw a funnel chart to determine whether the included studies have publication bias, and use Harbord weighted linear regression to quantitatively test the publication bias. When P < .05, it is considered that there is a significant publication bias.We will use Stata 15 software  to complete the meta-analysis. Specifically as follows: The confidence interval (CI) for continuous and dichotomous variables will be set to 95%. For dichotomous variables, we will apply the odds ratio (OR) to analyze. For continuous data, the mean difference (MD) or standardized MD (SMD) with 95% CI will be estimated. For continuous variables with the same measurement unit and little difference in means, we will use the WMD, and for continuous variables with different measurement units and large differences in means, we will use the SMD. Heterogeneity analysis will be calculated based on the 2.7In consideration of the systematic review of this protocol, ethical ratification is not required. In this study, participants were not recruited and data were not collected from participants. The review will be disseminated through peer-reviewed publications.3 Sangbaipi decoction is extensively applied to the therapy of AECOPD in China. However, owing to the low quality, small sample size, and methodological heterogeneity of these studies, this conclusion is not convincing. Consequently, it is necessary to systematically evaluate the clinical efficacy and safety of Sangbaipi Decoction in the treatment of AECOPD patients, and provide high-quality evidence for its clinical application.COPD is a common, preventable and treatable disease that is characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles or gases. The chronic airflow limitation that is characteristic of COPD is caused by a mixture of small airways disease and parenchymal destruction, the relative contributions of which vary from person to person. and immunomodulating activity, Banxia has protective effects against allergic airway inflammation, its treatment protected the airway from ICS withdrawal-induced mucus hypersecretion and airway inflammation by inhibiting ERK activation, Zisuzi has anti-inflammatory and immune-regulating pharmacological effects. Huangqin possesses anti-inflammatory functions by inhibiting hyperpermeability, expression of CAMs, and adhesion and migration of leukocytes. Evidence of the efficacy and safety of Sangbaipi decoction for AECOPD will be provided by this study, it will be able to assist clinicians in making Sangbaipi decoction-related decisions and will be beneficial to patients with AECOPD in the world. The design of this protocol conforms to the guideline of Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015. After completion, the results of this systematic review and meta-analysis will be submitted to a peer-reviewed journal.Sangbaipi decoction is composed of Mori Cortex (Sangbaipi), Arum Ternatum Thunb (Banxia), Perillae Fructus (Zisuzi), Amygdalus Communis Vas (Kuxingren), Fritillariae Thunbrgii Bulbus (Zhebeimu), Scutellariae Radix (Huangqin), Coptidis Rhizoma (Huanglian), and Gardeniae Fructus (Zhizi), and has the effect of clearing away heat and reducing phlegm. Pharmacological researches show that Sangbaipi has anti-inflammatory effectsConceptualization: Jiazhou Li, Huashan Pan.Data curation: Wenjiang Zheng.Funding acquisition: Chunxiang Jing, Huashan Pan.Investigation: Wenjiang Zheng.Methodology: Jiazhou Li, Junlin Jiang.Project administration: Huashan Pan.Software: Jiazhou Li, Junlin Jiang.Supervision: Chunxiang Jing.Validation: Jiazhou Li, Junlin Jiang.Writing – original draft: Jiazhou Li, Junlin Jiang.Writing – review & editing: Huashan Pan.


Objective: The aim of this study is to evaluate whether radiomics imaging signatures based on computed tomography (CT) could predict peritoneal metastasis (PM) in gastric cancer (GC) and to develop a nomogram for preoperative prediction of PM status.Methods: We collected CT images of pathological T4 gastric cancer in 955 consecutive patients of two cancer centers to analyze the radiomics features retrospectively and then developed and validated the prediction model built from 292 quantitative image features in the training cohort and two validation cohorts. Lasso regression model was applied for selecting feature and constructing radiomics signature. Predicting model was developed by multivariable logistic regression analysis. Radiomics nomogram was developed by the incorporation of radiomics signature and clinical T and N stage. Calibration, discrimination, and clinical usefulness were used to evaluate the performance of the nomogram.Results: In training and validation cohorts, PM status was associated with the radiomics signature significantly. It was found that the radiomics signature was an independent predictor for peritoneal metastasis in multivariable logistic analysis. For training and internal and external validation cohorts, the area under the receiver operating characteristic curves (AUCs) of radiomics signature for predicting PM were 0.751 , 0.802 , and 0.745 , respectively. Furthermore, for training and internal and external validation cohorts, the AUCs of radiomics nomogram for predicting PM were 0.792 , 0.870 , and 0.815 , respectively.Conclusions: CT-based radiomics signature could predict peritoneal metastasis, and the radiomics nomogram can make a meaningful contribution for predicting PM status in GC patient preoperatively. T, N staging, Greater Omental Milky Spot, and Troponin I2) could predict PM status in GC  is one of the most common human malignancies and the third leading cause of cancer-related deaths worldwide –3. Surgius in GC , 8, but us in GC . Howeverus in GC . TherefoRadiomics, an arising field that involves converting digital medical images into mineable data, analyzing data, and improving medical decision, has attracted increasing attention in recent years , 11. WitThe purpose of this study was to establish a radiomics signature for predicting the PM status in GC patients on the basis of preoperative CT information and to further develop a radiomics model that incorporates the clinicopathological findings and radiomics signature for the personal prediction of PM status in patients with GC preoperatively.T stage (cT) and N stage (cN) of patients. The details are shown in This study was approved by the ethics committee of every participating center, and the informed consent requirement was waved. We retrospectively selected three independent cohorts of patients with GC in pathological T4 stage. The training and internal validation cohorts comprising 562 and 106 consecutive patients, respectively, with total or partial radical gastrectomy were obtained from Sun Yat-sen University Cancer Center between January 2008 and December 2012 and January 2013 and December 2013, respectively. The external validation cohort that comprised 287 consecutive patients was obtained from Nanfang Hospital of Southern Medical University  between January 2007 and December 2013. Clinicopathological data of each patient were collected retrospectively. Peritoneal metastasis status was divided into two outcome categories: PM-negative status [PM(–)] and PM-positive status [PM(+)]. All the diagnoses of PM status were based on the laparoscopy surgery and pathological examination.Contrast-enhanced abdominal CT of patients was performed by the multidetector row CT (MDCT) systems . To standardize the image acquisition, portal venous phase contrast-enhanced CT images were retrieved from the picture archiving and communication system (PACS)  in Digital Imaging and Communications in Medicine (DICOM) format for feature extraction . The detITK-SNAP software (www.itksnap.org)  in Matlab R2016a (The MathWorks Inc.) to extract and calculated the radiomics features of these images. The inter- and intraobserver variability of radiomics feature extraction of the two radiologists was initially analyzed with 100 randomly chosen images for ROI-based texture feature extraction; details are shown in All the CT images were reviewed by two experienced radiologists who both had clinical experience in abdominal CT study interpretation for more than 10 years. Based on the consensus of these two radiologists, the tumor manual segmentation was performed and checked with nap.org) . They coIn order to predict the PM status of patients with GC, we used the least absolute shrinkage and selection operator (LASSO) logistic regression model to select the optimal radiomics features from the primary texture features, and then, the development of the radiomics score (Rad-score) was constructed in the training cohort . For furP < 0.05 in each cohort were then entered into the multivariate analyses. We used the likelihood ratio test with Akaike's information criterion as the stopping rule to apply the backward step-wise selection . The consistency between the predicted and actual probability of PM status was graphically represented by calibration plots.The potential net benefit of the predictive models was assessed by the decision curve analysis (DCA), which is popular as a new method for evaluating predictive model recently . The dect-test, unpaired, one-way ANOVA, or Mann–Whitney test were used for comparison. For categorical variables, the χ2 test or Fisher's exact test was used to compare. Standardization of the image features was applied by transforming the data of each feature into new scores with a mean of zero and a standard deviation of 1 (z-score transformation) (http://www.r-project.org), and the nomograms and calibration plots were conducted by using the R version 3.5.3 with rms package. For all tests, P < 0.05 was thought to be statistically significant.For continuous variable values, the two-tailed rmation) , 30. Mosn = 562), internal (n = 106), and external validation cohort (n = 287). As are shown in the tables, the clinical characteristics of patients among the three cohorts have no statistical difference. PM(+) status occurred in 90 (16.0%) patients, 17 (16.0%) patients, and 62 (21.6%) patients in the training, internal, and external validation cohort, respectively (ectively .The inter- and intraclass correlation coefficients (ICCs) for the two radiologists' extracted features were both higher than 0.75, indicating that the inter- and intraobserver agreements of radiomics feature extraction of the two radiologists were good, so all outcomes were calculated on the basis of the measurements of the first radiologist. Details are summarized in Rad-score = −1.429359e−03 × Eccentricity + 1.232216e−02 × Exten – 9.887834e−02 × GLCM_IMC1-0.5 + 8.977322e-02 × GLCM_MaximumProbability-0.5. Details are shown in On the basis of 562 patients in the primary cohort, 292 features were extracted from the CT image by using Matlab R2016a. Then, the 292 features were reduced to 11 potential predictors  by beingThe relationships among PM status, Rad-score, and clinical characteristics in each cohort were determined by three heatmaps –S6. In tP < 0.01, P < 0.01, In the training cohort, the Rad-score between PM(–) and PM(+) patients was significantly different  are integrated in our radiomics nomogram. According to the nomogram, the status of the disease could be comprehensively reflected, and the accuracy of prediction could be obviously improved. Calibration plots and ROC analysis were used to validate the nomogram. The nomogram showed excellent prediction with a good calibration. What is more, high AUCs were demonstrated in our radiomics nomogram both in internal and external cohorts when predicting the PM status; this could provide more valuable information for determining the need for adjuvant therapy and the adequacy of surgical resection, thus aiding in pretreatment decision making.In this study, our radiomics signature and nomogram could provide meaningful message for preoperatively predicting PM status. In the future, we will put a preoperative prediction model into effect to help provide proper surgical procedures or select candidates with high risk for laparoscopy exploration and treatment based on the comprehensive consideration of the information of the radiomics features.However, there are still limitations in our study. Although the radiomics signature and nomogram could provide meaningful message for predicting PM, the nomograms were developed and externally validated in three retrospective data sets from two Chinese institutions; thus, these results need to be validated in a larger population with a multicenter and prospective study in the future, which could develop high-level evidence needed for clinical use. In addition, this predictive model is suitable for those who were preoperatively diagnosed cT3 or cT4, as these patients are more likely to have the risk of PM; however, clinical and pathological stages are sometimes inconsistent, especially in gastric cancer . For exaIn conclusion, this study demonstrated that the radiomics signature based on CT can be used as a predictor for predicting peritoneal metastasis in GC patients. Besides, this study revealed that the radiomics nomogram, which combined the clinicopathological risk factors with the radiomics signature, can be effectively used to promote the preoperative individualized prediction of PM status in patients with GC.All datasets generated for this study are included in the article/The studies involving human participants were reviewed and approved by the Ethics Committee of Nanfang Hospital, Nanfang Hospital, Southern Medical University; the Ethics committee of Sun Yat-sen University Cancer Center, Sun Yat-sen University Cancer Center. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.GL, YX, and ZZ: guarantor of the article. GL, YX, ZZ, YJ, WH, and KZ: conception and design. YJ, WH, KZ, CC, QY, ZH, SY, YH, JX, JY, and HL: collection and assembly of data. WH, YJ, RX, ZH, JX, ZS, and JY: data analysis and interpretation. All authors: manuscript writing and final approval of manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


The results showed that students with MDs and RDMDs suffered from PM deficits. Among the subtypes of LDs, the deficit is different. The students with RDMDs showed a wide range of defects in PM, shifting, inhibition, and updating. In comparison, students with MDs experienced deficits in PM and shifting, while students with RDs experienced a deficit only in updating. For the RD group, the RDMD group and the TD group, updating, and shifting significantly predicted PM. For the MD group, only shifting significantly predicted PM performance, but PM deficits were not completely confined to shifting deficits.Students with learning disabilities (LDs) suffer from executive function deficits and impaired prospective memory (PM). Yet the specificity of deficits associated with different types of LDs is still unclear. The object of the present research was to compare subgroups of students with different forms of LDs (<25th percentile) on executive function and PM. Students with a mathematics disability (MD,  Prospective memory (PM) refers to the memory of expected behavior to be performed at an appropriate time or situation in the future. There are two ways in which PM retrieval occurs: event-based PM is when an environmental cue signals the appropriate time to perform an intended action, such as remembering to do one’s homework when seeing one’s school bag; a time-based PM, such as remembering to go to a meeting at 16:00. Due to the presence of external cues, event-based PM tasks are simpler than time-based PM tasks, which require more self-initiation . PM playProspective memory tasks are common in daily life, and PM errors may account for more than half of all daily memory problems . ConsistSeveral studies have shown that PM is significantly related to learning disabilities (LDs). Students with LDs, especially LDs in math (MD) report more PM failures , 2018. DHowever, our knowledge about the influencing factors and cognitive mechanisms of PM in LDs is still limited. A previous study defined LDs based on lower-order skills, calculations for math disability (MD) and word reading for reading disability (RD), which are the dominant classification strategies in the LD learning disabilities literature. RDs and MDs are common and often occur together (RDMD), and they are typically defined by reading and math subtests of the same battery of standardized achievement tests e.g., . Few stuExecutive function is a high-level cognitive process of students and the core of students’ cognitive function which can make students produce purposeful and coordinated behaviors, including three functional domains: shifting, updating, and inhibition . ImpairmExecutive functions are assumed to be involved in PM . A largeDespite the repeatedly expressed idea that EF and PM may be related, only a few studies so far have explored the role of distinct EF facets in PM performance . In addiA substantial number of studies showed students with LDs have problems in executive function e.g., . The curStudies have suggested that students with RDs perform poorly in reading comprehension, problem solving, and updating tasks than typical students , especiaCompared with those of typical students, the defects of students with LDs in executive function (WM or inhibitory control or shifting) may be one of the most notable reasons for their lower learning potential . EvidencIn the current study we focused on disentangling the significance of the three facets of executive control  for predicting PM performance among students with different types of LDs  who completed an extensive battery of measures of PM and executive functions. The specific predictions were as follows:(1)Based on the study of executive function defects in LDs, we tentatively predicted that weaknesses in updating, inhibition, and shifting would emerge as significant weaknesses in groups with RDMD. In contrast, we expected updating difficulties to be associated with RDs but not MD, and anticipated that the group with MDs would exhibit a specific deficit in shifting.(2)Based on the RDs, MDs, and RDMDs that define the groups, we anticipated that the PM deficits would be most pronounced in the RDMD group. We also hypothesized that the PM level of students with LDs would be lower than that of typical students. As previous research did not distinctly separate RDs and MDs, and the existing literature on RDs and PM is rather scarce, no specific prediction was formed in this regard.(3)Regarding to the effect of executive function deficits on predicting PM deficits in students with different forms of learning difficulties, we expected students with MDs to show poor performance on measures and that the ability of shifting would significantly predicted PM performance. However, for the RD group, we expected that updating would significantly predict PM performance.Twenty-seven students with RDs , 30 students with MDs , 27 students with RDMDs , and 30 TD students  were recruited from a junior middle school in Henan (grades: 7–9). All students were enrolled in regular classrooms. Before enrolling in the study, they were excluded for left-handedness, color-blindness, and possible mental disorders.Z scores. Some studies have suggested that students with Reading (language) scores below the 25th percentile and Mathematics scores above average were considered as RDs; those with Mathematics scores below the 25th percentile and Reading scores above average were considered as MDs; and students with both (Mathematics and Reading) scores below the 25th percentile were considered as students with RDMDs (The inclusion eligibility criteria for the LD group were as follows : (1) stuth RDMDs . These cth RDMDs , and 84 All the typically developing participants in the control group need to meet the following criteria: (1) the scores of the AAT and scores of two academic exams are above the middle level; (2) the scores of the PRS are more than 65; (3) the RSPM score is at the normal level; (4) matched on intelligence.F = 1.90, p = 0.13 and IQ, F = 2.07, p = 0.11, showed no significant differences between all the groups. With respect to the score of Learning Adaptability Test and Pupil Rating Scale, there was no significant difference between MD group and RD group, and TD groups outperformed the MD and RD group. RDMD group showed significantly poorer performance than the other three groups. In terms of Reading score, there was no significant difference between MD group and TD group, and both groups showed significantly better performance than the RD and RDMD group. With respect to Mathematics score, there was significant difference between RD group and TD group, and both groups outperformed the MD and RDMD group.The demographic differences of the four groups were listed in The students used a laptop computer equipped with Tool book and E-prime2.0 software for individual testing. The experiments were conducted in a quiet, sound attenuated room, and subjects were seated with their eyes approximately 100 cm from a 17-in screen. All stimuli were displayed in the center of the screen . Each participant took part in two 40-min sessions 1 week apart. In session 1, participants were required to complete the PM task, the Stroop color-word test. In session 2, they were presented with the N-back task, the More-odd shifting task (MOS). The order of the tests was counterbalanced for sessions. Analyses indicated no effect of presentation order on performance of any of these tests.The role of executive function in students’ PM performance was examined with several tasks: The N-back task, the Stroop color-word test, and the MOS.Updating was measured using the N-back task. In the task, a series of one-digit numbers (from 1 to 9) in a random sequence was shown to the participants in the center of the computer screen . Task difficulty was varied using three workloads . Participants were asked to press the “F” button with one index finger when the number that appeared on the screen was the same as the target number 3 for the 0-back task, the number presented one trial back for the 1-back task and the number presented two trials back for the 2-back task. Conversely, the participants were asked to respond by pressing the “J” button if the presented number did not meet the “match” criterion . The matInhibitory control was measured using the Stroop color-word test . In the To assess shifting, we used the well-established MOS referring to Salthouse’s paradigm . In the In the study we adopted dual task paradigm used in the study of The phrases were obtained on the basis of category naming experiments. In the category naming experiment, 27 categories familiar to the subjects were selected , and theThere were 27 blocks each of which consisted of three stages. In the coding stage: two PM cue trials (each one consisting of two phrases with the same semantics and color) were presented for 2,000 ms followed by 1,000 ms of blank screen. Participants were asked to remember the two phrases, including their semantics and colors (PM memory tasks). In the distraction task stage: a three-digit number appeared on the screen after the coding stage lasting 3,000 ms, and participants were required to perform a “minus three” task to avoid repeating items they had just learned. In the ongoing task stage each block contained 24 trials which were divided into 22 ongoing activity trials and 2 PM cues (PM tasks were embedded in the ongoing tasks). Participants would press the “1” key if they judged that the colors of the two phrases were same and the “2” key if the colors of the two phrases were different without considering the semantics. However, participants were instructed to press the “0” key if they saw the previous PM target cues again as presented in coding stages on the screen without making relevant judgments. In each block, PM target cues occurred once in the first 11 trials and once in the last 11 trials. The correct response time and accuracy to the PM target cues were calculated as the dependent measure. Before the formal experiment, participants were allowed to complete a practice block to ensure that they fully understood the whole experimental procedure.d effect size (ηp2) were calculated to determine differences between groups on each task. Bonferroni correction was applied for all analyses when multiple comparisons were made. Correlation analysis, stepwise regression analysis and hierarchical regression-based analysis were used to further determine whether executive function could explain the differences between the TD group and each of LD groups on PM tasks.One-way multivariate analyses of variance (MANOVAs), one-way analyses of variance (ANOVAs), and Cohen’s SPSS 20.0 was conducted for data collection and statistical analysis. The reaction time data of each participant for false responses and non-responses were deleted. RTs data was calculated based on a cutoff value of ±3 SD from the mean per participant . Given tZ-scores by standardization based on all the participants. Descriptive statistics for the executive functioning tasks, PM task of each group and comparison of performances for all the groups are displayed in k = 0.47, F = 10.83, p < 0.001, ηp2 = 0.23. Secondly, ANOVAs were run for N-back, SCWT, and MOSs, respectively.Firstly, a one-way MANOVA was conducted on RTs and accuracy of N-back, RTs of SCWT and MOSs and revealed a significant medium group main effect, Wilks’s F = 16.08, p < 0.001, ηp2 = 0.31; Further pairwise comparisons with Bonferroni adjustment revealed that the TD group, RD group, and MD group performed significantly better than the RDMD group (ps < 0.001). The TD group also performed significantly better than the RD group (p < 0.01). The TD group outperformed the MD group at a marginally significant level (p = 0.06), and the RD versus MD contrast was not significant (p = 0.39). The same analysis on N-back accuracy revealed that, there was no significant main effect of group.For the mean RTs for the N-back task, there was a main effect of group condition, F = 19.76, p < 0.001, ηp2 = 0.35; Further pairwise comparisons with Bonferroni adjustment revealed the RTs of the TD group, RD group and MD group were significantly shorter than the RTs of the RDMD group (ps < 0.001) and RD group was significantly shorter than the RTs of the MD group (p < 0.05), and there were no significant differences between the TD and RD groups and between the TD and MD groups (ps > 0.01).The ANOVA revealed significant large group differences on the mean RTs of the SCWT task, F = 14.22, p < 0.001, ηp2 = 0.28; Further pairwise comparisons with Bonferroni adjustment revealed the RTs of the TD group was significantly shorter than the RTs of the MD group and RDMD group (ps < 0.001). RD group was significantly shorter than the RTs of the RDMD group (p < 0.001), but there was no significant difference between the other two groups (ps > 0.01).For the mean RTs of the MOS task there was a main effect of group, F = 9.28, p < 0.001, ηp2 = 0.20.Similarly, a one-way MANOVA was conducted on RTs and accuracy of the RTs and accuracy of PM task and revealed a significant medium group main effect, Wilks’ λ = 0.64, F = 13.86, p < 0.001, ηp2 = 0.27; Further pairwise comparisons with Bonferroni adjustment revealed that the RTs of the TD group and RD were significantly shorter than the RTs of the MD group and RDMD group (ps < 0.001), but there were no significant difference between the TD and RD groups (p = 0.53) and between the MD and RDMD groups (p = 0.33). The same analysis on PM accuracy showed that, there was a main effect of group, F = 7.45, p < 0.001, ηp2 = 0.17. Further analysis showed that performance was best in the TD group, which was significantly higher than the RDMD group (p < 0.001), but there was no significant difference between the other two groups (ps > 0.01).Two ANOVAs were run for the RTs and accuracy of PM task, respectively. For the mean RTs of the PM task there was a main effect of group, ps < 0.05) and shifting (ps < 0.05). However, PM response time was not correlated with the response time of inhibitory control for all the four groups.Pearson’s correlation see  was usedStepwise multiple regressions were performed to examine the impact of updating, inhibitory control and shifting on PM response time respectively. For the RD group, updating and shifting significantly predicted the PM and explained 36.4% the variance in the PM. For the MD group, shifting significantly predicted the PM and explained 11.6% the variance in the PM. For the RDMD group, updating and shifting significantly predicted the PM and explained 56.8% the variance in the PM. For the TD group, updating and shifting significantly predicted the PM and explained 53.3% the variance in the PM. ps > 0.05). Only updating and shifting still significantly predicted the PM (ps < 0.05), and the MD groups still performed poorer than the TD group on PM tasks. Thus, PM deficits in students with MD groups cannot be completely attributed to their executive function deficits.Furthermore, a regression-based analysis method was conducted to further examine whether the executive function deficits explain the PM difference between the TD group and other three groups. By using the dummy coding, we created the variable “group” was dummy-coded with TD as reference group . The effThe present research was the first to disentangle the significance of the three main facets of executive control  for predicting PM performance among different types of LDs. The results showed that students with MDs and RDMDs suffered from PM deficits. The deficit profile varied between groups of LDs. Students with RDMDs showed extensive deficits in PM, shifting, inhibition, and updating. In comparison, students with MDs exhibited PM and shifting deficits, while students with RDs exhibited only updating deficits. Furthermore, the results suggested that executive function deficits and PM in students with MDs were relatively independent.In the current study, we assessed three executive functions to investigate the executive function deficit profile for students with LDs. In terms of executive functioning skills, some previous studies confirmed that different types of LDs have different executive function deficits. The separability of the central executive function shows the specificity of students with different types of LDs in different executive function tasks. Our findings showed that students with MDs also experienced executive function problems in shifting. Students with RDs experienced updating deficits, whereas students with RDMDs suffered from extensive executive function deficits in shifting, inhibition, and updating. These findings were consistent with previous studies that have indicated impaired executive functioning in students with RDMDs .The results show that students with MDs (and RDMDs) had difficulties in shifting, which is consistent with previous studies . HoweverFurthermore, students with RDs (and RDMDs) exhibited updating deficits. This result was consistent with a previous study that indicated impaired updating in students with RDs . Smith-SOur results indicate that students with MDs (and RDMDs) suffered from PM deficits, which was in line with the findings of impaired event-based PM in individuals with LDs , 2018. TOur results showed that students with RDMDs showed extensive deficits in shifting, inhibition, and updating. Compared with the TD group, the RDMD group might have suffered from significant deficits in PM. The results of the task shifting performance tests showed that the MD group performed worse than the RD and TD groups. No significant differences were found for the inhibition and updating tasks between the MD and RD groups. Although RD students had updating deficits in executive functions compared with the TD group, the difference between the MD and RD groups was not significant. Furthermore, we found a weak, but marginally significant, difference in updating performance between the MD and TD groups. Additionally, the MD group showed PM deficits that might have been derived from an impaired shifting ability. Among the three LD groups, regarding the extent of damage in executive functions, the RDMD group was first, the MD group was second, and the RD group was last.It should be noted that our results indicated that students with RD did not show PM deficits, which could be due to their intact shifting abilities. The preparatory attentional and memory process theory proposed that the successful performance of the prospective component of PM involves shifting between processes related to the ongoing task and processes related to evaluating responses to the environment on the periphery of one’s attentional focus . This thWe further investigated the role of executive functioning  on the PM deficits in different types of LDs. The results showed that PM was positively correlated with updating and shifting for each group. Participants with better updating and shifting performed better on the PM task. However, PM was not correlated with inhibitory control, which indicated that PM deficits were not affected by inhibitory control. Our results showed that most executive functions were significantly correlated with the PM tasks, confirming the notion that there is a close relation between executive functions and PM.Stepwise regressions revealed that shifting and updating significantly predicted the PM performance for the RD group, RDMD group, and TD group. Shifting is helpful for students to flexibly change their resource allocation in the PM task and is an important guarantee for students to successfully complete the PM task. Additionally, we speculated that updating may also play an important role in PM. The better the updating is, the greater the memory span, the more room there is to store and process relevant information, and the better students perform on PM tasks. In general, many of the abilities required to successfully complete PM tasks are affected by updating . Of courHowever, after partialing out the effects of executive function, we found that there were no significant group differences between the TD and RD groups and between the TD and RDMD groups on PM tasks, and also no significant interaction effect between the group and executive functions. Only the group differences between MD group and TD group on PM tasks remained. Thus, our findings might indicate that the PM of RD and RDMD groups were mostly affected by executive function, while PM deficits of students with MDs are not completely caused by special aspects of executive function deficits, but may be other general cognitive functioning. This is consistent with the results from studies on students with autism spectrum disorder suggesting that the PM deficits in students with autism spectrum disorder were not entirely attributed to their deficits in some lower level executive function . So, we In this sense, many studies had discussed the relationship between event-related PM and executive function, but the results of previous studies were inconsistent on the predictive effect of various components of executive function on PM. Therefore, future studies should complement a variety of experimental tasks to further explore the relationship between central executive function and PM.The study had a number of limitations: first is the particularity of the applied cognitive tasks of executive function and PM. By using multiple indicators to evaluate each cognitive construct, the distortion caused by a single task indicator can be reduced. Future studies should use more different indicators to measure the cognitive factors of interest, and the present findings therefore await replication with other neurophysiological indicators. In addition, the sample groups consisted of students nearly from the junior school, which may also limit the generalizability of the present results to other populations. Moreover, the failure to find a correlation between the performance of the updating and inhibition tasks was surprising. Research showed that the three components of executive function accelerated from the ages of 7–12 years, but the development trend and speed of each component were different . The fasTo sum up, the results suggest that executive function is an important predictor of PM in students with LDs. The current results indicate that students with MDs suffer from deficits in PM, and those with RDMDs exhibit significant impairments and weaknesses in PM, shifting, inhibition, and updating. In contrast, updating deficits were uniquely associated with RDs, whereas difficulty shifting was specifically associated with MDs deficits. Stepwise regressions showed that shifting and updating significantly predicted PM performance for the RD group, RDMD group and TD group; for the MD group, only shifting significantly predicted the PM performance, but PM deficits were not completely confined to shifting deficits. In summary, these results suggest that RDs and MDs are separate but correlated disorders that sometimes occur due to shared executive functions risk factors that lead to weaknesses in PM.These findings have important implications: theoretically, our findings support the view that learning disorders such as RDs, MDs, and RDMDs are the result of multiple executive function deficits. Furthermore, we found evidence suggesting that executive function, specifically shifting and updating, are implicated in PM. The results of the present research imply that the level of executive function influences PM in different forms of LDs. Our findings further suggest that differences in shifting ability have a larger influence on PM in students with MDs. Overall, our results underscore the importance of the three components of executive function in the study of PM in LDs. Future research needs to further examine further the more roles of executive functions in student’s PM. Generally, the essence of PM in students with LD should be more completely studied, as it is a fundamental life skill that has substantial impacts on academic and interpersonal skills.In practice, as LDs are heterogeneous disorders, there is likely to be considerable variation in the central executive function profiles of these students. Meanwhile, it is important to assess different forms of LDs individually in all components of executive function, as this can direct the choice of interventions and can take into account the distinct profiles associated with RDs and MDs. Therefore, specific executive function training and instructions should be designed for different groups of LDs. For students with RDMDs, training tasks tapping all executive functions are recommended. Choosing inhibition tasks and updating tasks is preferred for executive function training for students with MDs. In contrast, shifting tasks and inhibition tasks are preferred for students with MDs. In other words, further investigation is needed to determine appropriate executive function training procedures for students with different forms of LDs.All datasets generated for this study are included in the article/supplementary material.The studies involving human participants were reviewed and approved by Ethics Committee of Henan University. Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.LJ and YC designed the study and drafted the manuscript. XJ and LW performed the study. JZ, QZ, and HG analyzed the data and edited the manuscript. YC revised the manuscript. All the authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Sagittal abdominal diameter (SAD) is an anthropometric index associated with visceral adiposity. It remains unclear whether SAD and its socio-economic correlates differ in women and men, which limits the epidemiological and clinical applications of the SAD measurement. The aims of this study are to examine the sex differences in SAD and its socio-economic correlates.A complex stratified multistage clustered sampling design was used to select 6975 men and 7079 women aged 18 years or more from the National Health Nutrition and Examination Survey 2011–2016, representative of the US civilian non-institutionalized population. SAD was measured in accordance to the standard protocols using a two-arm abdominal caliper. The sex differences in SAD and its socio-economic correlates were evaluated by performing weighted independent t tests and weighted multiple regression.p < .0001), and Hispanic and Asian men were associated with lower SAD than white men (both p < .01). Women born in other countries were more likely to have lower SAD than women born in the US (p < .0001), and so were men (p = .0118). Both women and men with a household income of <$75,000 had higher SAD than those with an income of over $75,000. The associations of age, race, and household income with SAD differed in women and men.SAD was lower in women than in men in the entire sample, as well as in all the subgroups characterized by age, race, birth place, household income, and body mass index except for non-Hispanic blacks and those with household income < $20,000. Adjusted for other characteristics, age, birth place, household income, and body mass index were associated with SAD in both women and men. Black women were associated with higher SAD then white women (SAD is lower in women than in men, in the general population as well as in the most socio-economic subgroups. While socio-economic correlates of SAD are similar in women and men, the associations of age, race, and household income with SAD vary across sex.Supplementary information accompanies this paper at 10.1186/s12889-020-09805-z. Accumulating evidence suggests that visceral adipose tissue is more strongly related to metabolic risk factors than subcutaneous adipose tissue , 2. WaisWomen are reported to have lower intra-abdominal/visceral adiposity than men while the difference is diminished and not consistently seen in the elderly –12. It rSocio-economic factors, such as age, sex, and education have been linked to the population distribution of SAD in a descriptive population study in Finland . AnotherIn this study, we used anthropometric data from the US National Health and Nutrition Examination Survey (NHANES) to address: 1) Sex differences in SAD in the entire population as well as in the subgroups characterized by age, race/ethnicity, education, birth place, and household income; 2) Sex differences in socio-economic correlates of SAD. Considering the important role of sex in cardiovascular diseases  and the Beginning in 1999, continuous NHANES is conducted by the National Center for Health Statistics in the Centers for Disease Control and Prevention. It includes a series of two-year cross-sectional nationally representative survey of US civilian noninstitutionalized population , 18. EacIn the present study, the sample of participants were chosen from the three most recent cycles of NHANES conducted in 2011–2016. The choice of cycles was determined by data availability of SAD, the only outcome measure in the present study: 2011–2012 represents the first cycle of collecting SAD measurements, and 2015–2016 is the most recent cycle for which data are available. Participants aged less than 18 years who were interviewed only but not examined, who were pregnant during the examination, and/or who had SAD measurements missed, were excluded from the study based on the following considerations. SAD, similar to BMI and WC, may have different definitions or meanings between children and adults, and the purpose of this study was to examine sex differences in SAD among adults. Participants with ‘interview only’ missed the examination of SAD which was our focus measure in the study. Pregnant women experienced dramatic changes in physiology and body shape, and their normal levels of SAD could not be reflected. After applying the above exclusion criteria, we had 14,054 individuals in the final study sample, including 6975 men and 7079 women.SAD was measured by a trained examiner when the participant was in the supine position on an examination table Figure  19]. An. An19]. The caliper’s lower arm was inserted under the small of the back making sure the upper arm exceeds the participant’s abdominal diameter. The shaft of the caliper was adjusted in a vertical position. The caliper’s upper arm was slid down to lightly touch the abdomen with the edge aligned with the iliac level line mark after the participant took in a gentle breath, slowly let the air out and then paused. The measurement was taken when the participant was in the resting phase and the caliper’s shaft was in the vertical position. Up to four SAD readings were taken following the above procedure. The SAD for each person was calculated as an average over the readings.2), overweight (BMI greater than 25.0 and less than 29.9 kg/m2), and obesity .Socio-economic characteristics considered in this study were all self-reported, including age, sex, race, education, birth place, and household income. They were chosen from a large number of socio-economic variables using model selection techniques and were only significant variables in relation to SAD. Age was categorized as under 30, 30–39, 40–49, 50–59, and 60 years or more. Race/ethnicity included non-Hispanic white, non-Hispanic black, non-Hispanic Asian, Hispanic, and other. The level of education was categorized as high school below, high school graduate/GED or equivalent, and college or above in terms of years in school. Birth place had two categories: born in the US and born in other countries. The family income was grouped into 4 categories: less than $20,000, $20,000–$44,999, $45,000–$74,999, and $75,000 or more. Weight and height were measured using standardized techniques and equipment. BMI was calculated as weight in kilograms divided by the square of height in meters, and then categorized as normal weight  were estimated and adjusted associations of sex with SAD were examined. Wald χ2 tests were useed to examine the significance of parameter estimates. The model was then conducted separately in women and men to identify socio-economic correlates of SAD and the sex differences in associations of the correlates with SAD were test by using weighted independent t tests.Average age of the study participants was 47.3 years: 47.4 years for women and 47.2 years for men. From Table p < .0001) , but there were increasing trends over age (trend p < .0001) for both women and men. In both women and men, SAD increased more rapidly at the age of 50 years or below compared to those at the age of > 50 years . Hispanics and non-Hispanic Asians had lower SAD than non-Hispanic whites whose SAD was lower than non-Hispanic blacks. Participants born in other countries had lower SAD than those born in the US. Participants with a household income of over $75,000 had lower SAD than those in other income categories of less than $75,000.Adjusted for other socioeconomic characteristics, age, sex, race/ethnicity, birth place, household income, and BMI were all associated with SAD Table . Overallp = .0021, p < .00001, and p = .002, respectively). Compared to non-Hispanic white, Non-Hispanic black was associated with higher SAD in women, and Hispanic and non-Hispanic Asian were associated with lower SAD in men. The associations of Hispanic and non-Hispanic black (vs. non-Hispanic white) with SAD differed across sex .Stratification analysis by sex shows that adjusted for other characteristics, age, birth place, household income, and body mass index were associated with SAD in both women and men Table . Older aOur results show that SAD was lower in women than in men in the overall population, as well as in the majority of subgroups defined by age, race/ethnicity, birth place, BMI, and household income. For example, in each BMI category , women tended to have an approximate 1.3 cm lower mean SAD than men, and the sex difference in SAD did not change over BMI categories Table . In addiBMI, WC and SAD are three measures of obesity and are highly correlated (Supplemental Table Although women have a lower mean WC than men, data from two prospective cohort studies of the Health Professionals Follow-up Study and the Nurses’ Health Study showed that WC predicted the adjusted relative risk of coronary heart disease in both women and men, and the correlation between WC and heart disease was even stronger in women than in men . A diffeSAD increased with age, and the trends in men and women were similar with respect to age. The results can be partly explained by the reports on visceral fat change over age in the previous studies , 30. TheAlthough mean BMI and WC among women and men increase in trends for the last two decades, the trends have leveled off in recent years after 2010 . In thisIn this study, socio-economic correlates of SAD were similar in women and men. Older age, higher BMI, born in the US, and lower household income were all associated with higher SAD in both women and men. However, race/ethnicity groups were differently associated with SAD. Compared to non-Hispanic whites, being Hispanic and non-Hispanic Asian was associated with lower SAD in men but not in women; being non-Hispanic black was associated with higher SAD in women but not in men. A study of subjects, including 66 African American, 72 Hispanic, and 47 white men and women, showed that middle-aged and older African-American men and women had lower visceral fat than Hispanic and white peers. The reports are controversial to our results about racial/ethnic difference in SAD that measures levels of visceral fat. We conducted an analysis using a nationally representative sample of 14,054 individuals, including 3134 non-Hispanic blacks, 3359 Hispanics, and 5425 non-Hispanic whites, and therefore, our data had more power to reflect the difference in visceral fat among racial/ethnic groups.NHNAES is a national survey of the US civilian non-institutionalized population using a complex stratified multi-stage sampling design. By incorporating into data analysis the features of NHANES design including sampling weights, selection probabilities, and geographic clustering, our results can reasonably be generalized to the entire US non-institutionalized population and the socioeconomic subpopulations of men and women. Another strength of our study is the large sample size that ensures the analysis power for robust and unbiased estimates when comparing the difference in SAD between women and men across socio-economic subgroups. There are several limitations in this study. NHANES is a cross-sectional survey, and the associations of socio-economic factors with SAD could not be interpreted as causal effects. SAD was measured by a two-arm sliding-beam caliper with the possibility of certain levels of measurement errors in SAD. However, trained examiners recorded 4 repeated SAD readings that could minimize the measurement errors. Certain other factors not considered in this study could confound the results, as we focused on sex difference in SAD and its correlates.In summary, women had lower SAD than men not only in the overall population, but in the majority of subgroups determined by socio-economic factors, such as age, race, birth place and household income. Given that increased sagittal diameter is linked to intra-abdominal fatness and cardiometabolic risk in both men and women , 7, it wAdditional file 1: Supplemental table 1. Correlations between BMI, WC, and SAD.


Background: Orthostatic hypotension (OH) is a common disease of the elderly. It is generally believed that the pathogenesis of OH is related to the impairment of autonomic nerve function and the decreased vascular capacity regulation. This study aims to explore the relationship between OH and heart rate variability (HRV) parameters, which reflects autonomic nerve function; ankle-brachial pressure index (ABI), which reflects the degree of vascular stenosis; pulse wave velocity (PWV) index, which reflects vascular stiffness; and frailty index (FI), which reflects the overall health status of the elderly.Methods: From January to September 2018, 24-h HOLTER monitoring, PWV, and ABI were performed in 108 elderly patients with OH and 64 elderly patients who underwent physical examination in our hospital. Analysis software was used to record the subject's standard deviation of the cardiac cycle (SDNN), the standard deviation of the 5-min average cardiac cycle (SDANN), the square root of the average square sum of consecutive n-interval differences (rMSSD), the percentage of the number of adjacent cardiac interval differences >50 ms (pNN50), low frequency (LF), high frequency (HF), very low frequency (VLF), and low frequency/high frequency ratio (LF/HF). Then, FI was evaluated qualitatively and quantitatively in the form of a scale.Results: There was no statistical difference between the two groups on the basis of age, sex, body mass index (BMI), low-density lipoprotein (LDL), resting heart rate, blood pressure, fasting blood glucose, long-term medication, etc. There were significant differences in PWV, SDNN, LF, VLF, and LF/HF between the two groups (P < 0.05). The risk factor of OH in the qualitative (P = 0.04) and quantitative (P = 0.007) index FI was higher in the OH group than in the control group. The risk factors of OH were PWV, SDNN, VLF, LF/HF, and FI, where FI was positively correlated and LF/HF was negatively correlated.Conclusions: The pathogenesis of OH is related to vascular stiffness, imbalance of autonomic nerve regulation, and its comprehensive health status in the elderly. However, arteriosclerosis has not been confirmed as an independent risk factor.Clinical Trial Registration: Retrospectively registered, http://www.chictr.org.cn. Orthostatic hypotension (OH) is a common disease status of the elderly. Its incidence increases with age. According to American statistics, the prevalence rate of the community population aged over 65 was about 20–30% . In the At present, there are some studies on the pathogenesis of OH. Some studies have shown that non-neurogenic OH was related to autonomic nervous dysfunction and decreased vascular capacity regulation . ClinicaBased on the mechanism of decreased vascular volume regulation, combined with the characteristics of elderly patients, we speculated that there might be a correlation between atherosclerosis and OH, but there were few relevant reports. In consideration of the elderly with multiple mental disorders, we also tried to explore the relationship between the comprehensive state of the elderly and OH. Accordingly, we designed this study.From January to September 2018, 108 cases of OH elderly patients from the Geriatrics Department and Cardiology Department in the eastern district of Wuhan Puai Hospital were screened as observation groups (OH group). In the same period, 64 cases of elderly people from the Physical Examination Department in the eastern district of Wuhan Puai Hospital were taken as control group (CON group). Strobe statements were used for study identification, screening, and inclusion.(1) Age ≥65 years old, able to cooperate with researchers; (2) In the stable stage of the disease, stop intravenous infusion for more than 3 days; (3) OH group meets diagnostic criteria , with or(1) Atrial fibrillation or obvious arrhythmia; (2) Pacemaker implantation; (3) Diabetes; (4) Drugs, such as antidepressants, anti-Parkinson, anti-psychotic, Raas blockers, and Beta blockers that have a significant effect on autonomic nerve function are being taken; (5) At the stage of disease onset, needs clinical treatment, such as intravenous infusion; (6) Those who have not obtained informed consent and cannot cooperate.Refer to the definition in the expert consensus issued by the American Institute of Autonomous Neurology and Neuropathy in 1996: The blood pressure was measured every minute within 3 min after the change from lying position to standing position. The systolic and/or diastolic blood pressure decreased ≥20 mmHg and/or diastolic blood pressure decreased ≥10 mmHg within 3 min .n = 108).From January to September 2018, elderly OH patients from the Geriatrics Department and Cardiology Department of Wuhan Puai Hospital (age ≥65) were screened by the researchers under the condition of stable preexisting disease. The method was as follows: After the patient stayed in bed for 15 min, the researcher used a calibrated mercury sphygmomanometer to measure the blood pressure and heart rate of the lying humeral artery and recorded it. The patient's blood pressure and the heart rate of the same brachial artery were measured every minute after standing upright and recorded to 3 min after standing upright. Patients with reduced systolic pressure ≥20 mmHg and/or diastolic pressure ≥10 mmHg within 3 min were diagnosed as OH. After informed consent was obtained, a total of 108 cases entered the group and completed the study (n = 64).From January to September 2018, the elderly (age ≥65 years old) who came to the Physical Examination Department of Wuhan Puai Hospital for physical examination were enrolled by the researchers after OH detection. Ruling out OH diagnosis and obtaining informed consent, a total of 64 cases were enrolled and completed the study , resting blood pressure, heart rate, and medication. The following routine biochemical tests were performed: blood fat, blood sugar, improved ankle-brachial pressure index (ABI), pulse wave velocity (PWV), and 24-h HOLTER tests. Qualitative and quantitative scores of “frailty” were evaluated and recorded by a specially designated researcher. All data were reviewed and verified by two researchers independently.The ABI and PWV were measured using the VP-1000 automatic arteriosclerosis tester of OMRON Colin of Japan. Resting at least 5 min before the test, all subjects lay on the diagnostic bed on their backs, with the cuff tied to the upper and lower limbs in accordance with the operating rules. The upper arm sleeve belt air bag marked the brachial artery and the lower edge of the cuff was 2–3 cm from the elbow socket. The lower extremity cuff airbag mark was aligned with the inner side of the lower extremity, and the lower edge of the cuff was 1–2 cm from the inner ankle. The cuff was loosened moderately. The electrocardiogram (ECG) sensor was placed in the second left rib, body height parameters were input, the instrument automatically measured ABI and calculated PWV, and the researchers recorded the data.All subjects were monitored using 24-h HOLTER, the device was GE Seer Light Record box, and the heart rate variability (HRV) analysis software used was GE MARS Software. HRV analysis was based on the guidelines of the European College of Cardiology and the North American Pacemaker and Electrophysiological Society. NN intervals were RR intervals in sinus rhythm, and average NN intervals were the mean value of RR intervals in sinus rhythm. Intervals greater than or <30% of the average of the first four intervals are considered artifacts and removed from the analysis record. According to the automatic editing program, each ECG record was manually reviewed by two authors blinded to avoid abnormal QRS complex morphology, ectopic heartbeat, and motion artifacts, and to ensure that the HRV analysis program correctly marks the R wave, so as to accurately detect the R–R interval. Make corrections if necessary. According to the measurement standard, the following HRV measurements were calculated in the time domain and frequency domain .Time-domain related parameters:The standard deviation of normal-to-normal RR interval (SDNN), in ms.The standard deviation of the 5-min average cardiac cycle (SDANN), in ms.The square root of the average square sum of consecutive n-interval differences (rMSSD), in ms.The percentage of the number of adjacent cardiac interval differences >50 ms (pNN50), in%.Frequency-domain related parameters:For frequency-domain HRV analysis, RR time series were interpolated at 250 ms to obtain isometric values. Using fast Fourier transform (FFT), we quantified HRV in four frequency bands. Three characteristic frequencies were identified: LF, HF, and VLF when analyzing 2- to 5-min ECG recordings. ULF bands are identified with VLF bands in a 24-h recording.2.Low frequency (LF) band (LF power in the range of 0.04–0.15 Hz), in ms2.High frequency (HF) band (HF power in the range of 0.15–0.40 Hz), in ms2.Very low frequency (VLF) band (VLF power in the range of 0.003–0.04 Hz), in ms2.Ultra low frequency (ULF) band (ULF power in the range of 0.0001–0.003 Hz), in msWe also considered the LF/HF ratio.In this study, the Groningen frailty indicator (GFI) scale  was seleThe quantitative index of frailty adopted the currently recognized FI proposed by Rockwood et al. . FI is tList the common health deficits reflecting frailty that met the standards and with a score of 0–1 for each item. Each defect can be determined as multiple values according to the situation; for example, there are good, medium, and bad conditions, and the score can be set as 0, 0.5, and 1. You need 4 values to give  four scores. The corresponding individual situation was scored. The FI score was the ratio of the individual's current number of deficits score to the total number of deficits score. For example, consider that a health project data set had 50 variable items, each of which met the criteria considered to be a health deficit. If an individual did not have one, his FI will be 0/50 = 0 . If an individual had 10 deficits of 1 point, the FI index would be 10/50 = 0.20.According to the inclusion criteria of the FI project , referrit-test or a Bonferroni single-factor variance analysis (one-way ANOVA). The percentage of the comparison classification variable was tested using chi square. We determined the relevant risk factors for OH by the multiple logistic regression model. All statistical analysis was performed using SPSS 22.0 software. P < 0.05 was statistically significant.Quantitative data were expressed as mean ± SD, and qualitative data were expressed as the number of cases (percentage). The normal distribution of continuous variables was tested by Kolmogorov–Smirnov. The variance homogeneity test used Levene test. The continuous data of the normal distribution were evaluated by an independent-samples The Medsci sample size tools (MSST) was used to calculate the sample size. According to the matching ratio of 2:1 in the OH group and the CON group, a total of 255 study populations were included according to the results of the OH test. Through the relevant exclusion screening criteria, a total of 78 people failed. Subsequently, five more people were not eligible for the study because they could not cooperate with the experiment. In the end, 172 people entered the study . The steThere was no significant difference between the two groups in age, gender, smoking, drinking wine, BMI, resting blood pressure, resting heart rate, hypertension, hyperlipidemia, hyperuricemia, tumors, and cerebral infarction. There was no significant difference between the two groups in laboratory biochemical indexes, such as fasting blood sugar and LDL .Taking OH as the dependent variable and using age, gender, smoking, drinking wine, BMI, resting blood pressure, resting heart rate, fast blood sugar, LDL hypertension, hyperlipidemia, hyperuricemia, tumors, and cerebral infarction as independent variables, logistic regression analysis showed that the above indicators were not the risk factors of OH .The results showed that there were no significant differences in the DDD of antihypertensive drugs, calcium channel antagonists, alpha receptor antagonists, diuretics, and statins between the two groups . Taking P = 0.14) (P = 0.035)  . PWV was= 0.035) .P > 0.05). Compared with the CON group, SDNN in the OH group decreased significantly (P < 0.05) (P > 0.05). Compared with the CON group, LF, VLF, and LF/HF decreased significantly in the OH group (P < 0.05)  . In the  < 0.05) .P = 0.04) (P = 0.007)  . The qua= 0.007) .Taking OH as the dependent variable and using ABI, PWV, SDNN, SDANN, rMSSD, pNN50, LF, HF, VLF, LF/HF, and FI as independent variables, logistic regression analysis showed that PWV, SDNN, VLF, LF/HF, and FI were all predicted factors of OH. Among them, PWV and FI were positively correlated, and SDNN, VLF and LF/HF were negatively correlated. FI and LF/HF were the most affected .Similar to the literature , researcP > 0.05), while PWV in the OH group was significantly higher than that in the control group (P < 0.05). PWV reflects the degree of vascular stiffness. It was believed that the failure of lower limbs and visceral vessels to contract in time during the body position change of OH patients was related to the damage of sympathetic adrenergic system . In multiple regression analysis, SDNN, LF, VLF, and LF/HF were all predictors of OH (P < 0.05), and LF/HF was strongly correlated. It is suggested that the pathogenesis of OH is related to the imbalance of sympathetic and parasympathetic nerves.In healthy individuals, the periodic changes of HRV were accompanied by respiratory and blood pressure fluctuations . FrequenP = 0.04). In the quantitative index of frailty, there was significant difference between the two groups (P < 0.05). The OH group was significantly higher than the control group, indicating that frailty was related to OH. The results of the subsequent regression equation  also showed that FI is a predictor of OH. The relationship between them was linear and parallel.In clinical practice, we found that the incidence of OH patients was significantly related to their age. Therefore, in this study, we specially set an indicator “frailty” to reflect the comprehensive state of the elderly, and the results were consistent with our assumption. In the qualitative index of frailty, the percentage of frailty in the OH group (55.6%) was higher than that in the control group (39.1%) and had statistical significance . All patients gave informed consent for participation in this study, and written consent was obtained from each participating patient.The study was approved by the ethical committee of Puai Hospital affiliated with Huazhong University of Science and Technology, Wuhan, China  and conducted in accordance with the principles of the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was registered in the Chinese Clinical Trial Register (LL and HL conceived the present study, participated in the design, conducted the data analysis, and drafted the manuscript. HL and HC collected and assembled all the data. YL and LL commented on the manuscript drafts. YL provided the material and technical support and commented on the manuscript drafts. All authors have read and approved the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.