The discrete data structure and large sequencing depth of RNA sequencing (RNA-seq) experiments can often generate outlier read counts in one or more RNA samples within a homogeneous group. Thus, how to identify and manage outlier observations in RNA-seq data is an emerging topic of interest. One of the main objectives in these research efforts is to develop statistical methodology that effectively balances the impact of outlier observations and achieves maximal power for statistical testing. To reach that goal, strengthening the accuracy of outlier detection is an important precursor. Current outlier detection algorithms for RNA-seq data are executed within a testing framework and may be sensitive to sparse data and heavy-tailed distributions. Therefore, we propose a univariate algorithm that utilizes a probabilistic approach to measure the deviation between an observation and the distribution generating the remaining data and implement it within in an iterative leave-one-out design strategy. Analyses of real and simulated RNA-seq data show that the proposed methodology has higher outlier detection rates for both non-normalized and normalized negative binomial distributed data. The rise of RNA sequencing (RNA-seq) as a competing tool for differential expression analysis has launched considerable efforts to develop methods that effectively model and analyze count data produced by RNA-seq experiments. Unlike microarray experiments, which produce continuous probe intensities, RNA-seq measures RNA content through digital expression profiling by counting the number of sequencing reads that map to a particular feature . Given the dynamic range of RNA-seq data and practically no ceiling for quantification, extreme high counts (i.e. outliers) for a given feature are often present in one or more RNA samples within an experimental group. The presence of outliers substantially limits the power of differential testing ,2.RNA-seq counts are influenced by a number of decisions that must be made to generate expression data from total RNA. As a result, outlier read counts may arise from one of many stages, including biological harvesting of RNA, design implementation, and data processing techniques. For example, in animal studies, in order to obtain sufficient levels of RNA to be sequenced, multiple needle punctures might be necessary to acquire enough of the tissue to be sampled from a relatively small body size. In this case, the possibility of collecting a sample from non-target tissues increases, which could potentially affect read counts in a subset of features. On the data preprocessing side, the selected mapping pipeline and library construction also affect read counts. Since outliers may have biological or technical origins, accurately detecting outliers may help a researcher pinpoint their source and ensure data quality.edgeR . EA created the library and performed 50bp paired-end and strand-specific sequencing using an Illumina platform. A total of 25–35 million reads were generated per sample. Raw reads were aligned to the rat reference genome. The full experiment included multiple treatments; however, we focused only on the control group (n = 6) was selected to compare the performance of both methodologies in smaller sample size (and a different RNA-seq pipeline). RNA-seq data from six unrelated cerebellar cortex tissue samples sequenced by Wang et al. [The second dataset  [RNA-seq datasets were simulated to mimic real data using the R package npSeq . Under tnpSeq  and the 21,1.73) . The con21,1.73) .npSeq and setting the sample size of the second class equal to zero. The default values for number of features, percentage of significant features, and percentage of up-regulated significant features remained unchanged at 20000, 0.3, and 0.8, respectively. Outliers were added to the simulated dataset in a manner similar to the random method outlined by Soneson and Delorenzi [c × max{Yg,i}, where c is a random sample from the uniform distribution U. This process was repeated 100 times. Data were generated for sample sizes of n = 5,10,15,20,30, and 40 to represent a single treatment group.RNA-seq data for a single class was obtained by selecting the “twoclass” option in elorenzi . SpecifiiLOO and edgeR-robust (version 3.6.8). One of the aims of outlier detection is to identify potential problems with data quality; hence, outlier detection rates for real data were evaluated at the raw data level. Since DESeq2 performs analysis on normalized counts, it was omitted from real data analysis. An advantage of iLOO is its ability to return multiple outlier reads per feature. To make iLOO and edgeR-robust comparable, we adjusted the single outlier restriction implemented by Zhou et al. [edgeR-robust to be the 10th percentile of down-weighted Huber weights (r < 0.50). This adjustment allows the algorithm flexibility to return multiple extreme down-weighted observations per feature. In the edgeR-robust methodology, multiple observations with high counts for a given feature can and will be re-weighted to dampen adverse effects on expression analysis so the suggested modification is reasonable. In addition, iLOO algorithm was modified to reflect the mean of normalized sequencing depths (i.e. effective library sizes in edgeR).Outliers in real data were assessed with iLOO detected more outliers than edgeR-robust and also more outliers per feature. There was some overlap between iLOO and edgeR-robust in their identification of features with a single outlier count and features with two detected outliers. However, both methods uniquely classify read counts as outliers , iLOO has more power to detect outlying expressions. In addition, iLOO’s ability to detect down-regulated outlier counts is an important observation since down-regulated expressions are typically masked in most outlier methodologies. Lastly, iLOO detected four outlier read counts (feature ENSRNOG00000007092). Both methodologies were able to detect the two counts with extremely high values. However, iLOO detected two additional read counts. Given the range of expression for this feature in the bottom split panel of To draw conclusions about the effectiveness of both methods to detect aberrant observations, a scatterplot of raw RNA-seq counts for 6 features with outlier read counts is presented in iLOO is more robust at identifying distant observations and multiple observations per feature, especially when the feature-level data is variable , we applied the same analysis to the cerebellar cortex tissue samples from six unrelated donors . Both mevariable . The latiLOO with edgeR and iLOO with DESeq2 (version 1.4.5). Although edgeR and DESeq2 use similar normalization techniques, they differ in that scaling factors for edgeR apply to the sequencing depths and those for DESeq2 to read counts. Thus, in the first simulation study, we compare edgeR-robust to iLOO . Outlier accuracy is defined as the number of success outlier features divided by 2000. Likewise, non-outlier accuracy is defined as the proportion of success non-outlier features. Consideration of all three metrics provides the most thorough assessment.The metrics used to evaluate the performance of edgeR-robust simulation study are presented in iLOO achieves almost 80% accuracy for all three measures of accuracy. For sample sizes of 10 and higher, total, outlier, and non-outlier accuracy exceed 97%. Although total accuracy for edgeR-robust exceeds 90% at all sample sizes, the metric is predominately inflated by non-outlier accuracy. Results of the simulation study suggest that both methods perform reasonably well in minimizing the number of false positive calls; however, edgeR-robust appears to struggle to detect true outliers in small and moderate sample sizes. Results of the simulation study comparing iLOO  to DESeq2 show similar findings , the proposed method minimizes the prevalence of false positive calls and maximizes true outlier detection. Advantages of the iterative approach over existing methodologies were demonstrated in real data and simulated data and were observed in sample sizes as small as 5.Outliers in RNA-seq studies pose a number of unique obstacles to achieve sufficient statistical power. In this paper, we developed an iterative, univariate probability-based approach to outlier detection that addresses many of the challenges. A challenge that may need more attention is how to accurately detect multiple outliers. Since S1 FigiLOO and edgeR-robust in the Wang et al. dataset.The totals provided present the number of single outlier features identified by (DOC)Click here for additional data file.S2 FigiLOO (purple diamond), edgeR-robust (red diamond), and both methods (blue diamond) in the Wang et al. dataset.Scatterplot of raw counts for five representative features displaying counts identified as outliers by (DOC)Click here for additional data file.S1 R Code(DOC)Click here for additional data file.S1 TableNumber of features with 0, 1, and 2 detected outliers.(DOC)Click here for additional data file.S2 TableiLOO  to DESeq2. A full simulation study was carried out for each sample size setting consisting of 5, 10, 15, 20, 30, and 40 replicates.Summary statistics for total accuracy, outlier accuracy, and non-outlier accuracy are provided for the simulation study comparing (DOC)Click here for additional data file.


Post-traumatic orbital reconstruction remains a surgical challenge and requires careful preoperative planning, sound anatomical knowledge and good intraoperative judgment. Computer-assisted technology has the potential to reduce error and subjectivity in the management of these complex injuries. A systematic review of the literature was conducted to explore the emerging role of computer-assisted technologies in post-traumatic orbital reconstruction, in terms of functional and safety outcomes. We searched for articles comparing computer-assisted procedures with conventional surgery and studied outcomes on diplopia, enophthalmos, or procedure-related complications. Six observational studies with 273 orbits at a mean follow-up of 13 months were included. Three out of 4 studies reported significantly fewer patients with residual diplopia in the computer-assisted group, while only 1 of the 5 studies reported better improvement in enophthalmos in the assisted group. Types and incidence of complications were comparable. Study heterogeneities limiting statistical comparison by meta-analysis will be discussed. This review highlights the scarcity of data on computer-assisted technology in orbital reconstruction. The result suggests that computer-assisted technology may offer potential advantage in treating diplopia while its role remains to be confirmed in enophthalmos. Additional well-designed and powered randomized controlled trials are much needed. Orbital fractures occur in 40% of all craniomaxillofacial traumas1456Computer-assisted technology using computerized tomography (CT) plays an emerging role in orbital reconstruction during preoperative planning, implant design, intraoperative navigation and postoperative auditing. In preoperative planning, a mirror image overlay (MIO) is created based on the uninjured, contralateral orbit and is superimposed onto the images of the injured side1012While there are recommendations and reviews on the indication and timing of surgeryCompared computer-assisted technology versus conventional surgery.Used computer-assisted technology in the treatment of orbital reconstruction, including but not limited to preoperative planning, surgical navigation, or CAD/CAM implants.Included detailed description of the computer-assisted techniques used.Performed primary and/or secondary reconstruction of fractured orbital walls.Examined at least one of the following outcomes: diplopia, enophthalmos, or procedure-related complications.Studies were included if they:Computer-assisted technology were only used for diagnostic purposes.Orbital reconstruction for non-traumatic  cases.Outcomes were reported in a qualitative manner.Preoperative or postoperative outcome measurements were inadequate.Studies were excluded if:www.clinicaltrials.gov) and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) for any comparative studies. We used the Cochrane highly sensitive search strategy and combined with our search termsWe searched MEDLINE and EMBASE via the OVID platform, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov (Two reviewers (KHW and KKLC) independently assessed the titles and abstracts. In case of any unresolved discrepancies, a third reviewer (ALY) will arbitrate until a mutual conclusion was reached. We used a customized form to record the authors, year of publication, sample size, duration of follow up, fracture patterns, primary or secondary reconstruction, the modality of computer-assisted technologies used, surgical techniques, implants, and outcome measures. We collected outcome data at the last follow-up. We used reduction in enophthalmos measured by exophthalmometer in millimeter (mm); if these data were not available, then the percentage of patients showing enophthalmos at the last follow-up were analyzed. Likewise, we extracted the percentage of patient complaining of diplopia at the last follow-up. Number and types of complications were recorded.The quality of the studies was independently evaluated by 2 reviewers (KHW and KKLC) using the Cochrane Risk of Bias tools for RCTs2 statistic. If there was any significant heterogeneity between studies (p < 0.1), a random-effect model was used for pooling the data; otherwise a fixed-effect model was used.We used the Review Manager  for our meta-analysis. We analyzed the statistical heterogeneity of the included studies with the Cochrane Q-statistics chi-square test and IWe identified 239 titles and abstracts through our literature search and retrieved 12 articles for full text review. We included 6 studies in this systematic review according to our a priori criteria 192021222192021222320212222211920192223221919202120212223202122Procedure-related complications were documented in 3 studies192021Computer assisted surgery (CAS) (ICD-9-CM Intervention code 00.3) represents surgical concepts and methods utilizing computer technology for preoperative planning and intraoperative guidance. It includes image-guided navigation (IGN) and image-guided surgery (IGS). Such guidance improves accuracy of surgical gestures and reduces surgeon’s action and effort279Intra-operative navigation provides real-time feedback of anatomical location of the tracking device with respect to preoperative images4We did not identify any randomized controlled trials in computer-assisted technology for post-traumatic orbital reconstruction. Results of our systematic review were limited to cohort and case-control studies. Our review highlights the scarcity of relevant literatures. Clinical heterogeneities were present for the severities, location and number of fractures, primary versus secondary reconstruction, timing of surgery and surgical approaches including use of intraoperative navigation, implant types and materials. Methodological heterogeneities due to different type of study designs and operative approaches and clinical heterogeneities due to divergent patient groups limited us from performing meta-analysis.Three studies reported the number of patients with clinically significant enophthalmos (difference >2 mm)2021223334Post-traumatic enophthalmos is not only related to orbital volume expansion but also loss of ligamental support, soft tissue atrophy and contracture373839et al.2) were present in 85% in the assisted group and 88% in the control group. However, previous study showed that PDS implant was suitable only for smaller defects (<2.5 cm2)Post-traumatic diplopia can be caused by direct nerve or muscle injury causing paralytic strabismus or herniation/entrapment of muscle and/or surrounding connective tissue leading to restrictive strabismus. Our results showed that computer-assisted technology may provide additional improvements in diplopia compared to the conventional surgery. Fewer patients undergoing computer-assisted repair had residual diplopia except those in the study of Lauer Post-operative complications were similar in both groups with no statistical difference. These complications were inherent to the complexities and surgical approaches rather than the use of computer-assisted technologies.Revisions surgeries are more challenging as scarring occurs over inadequately reduced soft tissues, remaining bone fragments as well as malpositioned implants. Extensive dissection and osteotomies are often necessary and spatial orientation and visualization become more difficult21Existing evidence is deemed insufficient to determine the emerging role of computer-assisted technologies. Future randomized trials will have to address important confounders including size and pattern  of fracture, timing of repair (immediate versus delayed), types of implant and number of surgeons involved. It would also be relevant to study its impact among surgeons-in-training and in revision or complicated cases. Extended follow-up will allow evaluation of soft tissue atrophy, fibrosis and contracture on late-onset diplopia and enophthalmos. Finally, direct and indirect costs should be included in future studies.To our knowledge, this is the first systematic review on computer-assisted technologies for post-traumatic orbital reconstruction. Results are limited by the paucity of high-quality studies available. Our data suggests advantage in its use for treating diplopia but not enophthalmos. As attractive and innovative as other new technologies, it is not a prerequisite for good outcomes, particularly in simple cases. Despite the potential to reduce error and subjectivity, it is still far from being routinely used due to the incurred time and cost. This review highlights the need of carefully-designed, randomized controlled trials in assessing the indications, safety and efficacy, as well as cost utility of computer-assisted technologies in post-traumatic orbital reconstruction.How to cite this article: Wan, K. H. et al. The Role of Computer-Assisted Technology in Post-Traumatic Orbital Reconstruction: A PRISMA-driven Systematic Review. Sci. Rep.5, 17914; doi: 10.1038/srep17914 (2015).


Mould exposure has been linked to childhood asthma and bronchial hyper-responsiveness. Few studies have assessed beta--d-glucan (beta-glucan), a significant fungal cell wall constituent, in relation to asthma in adolescence.To determine whether house dust-derived beta-glucan exposure at age 7–10 is associated with the development and persistence of atopic and non-atopic asthma, and bronchial hyper-responsiveness (BHR) by age 11–14.Dust samples were collected from the 1995 Study of Asthma, Genes, and Environment (SAGE) birth cohort. This cohort was derived from Manitoba provincial healthcare administrative records of children high and low risk for asthma. Samples were collected from the homes of 422 children at age 7–10 and analyzed using beta-glucan and endotoxin-specific Limulus Amoebocyte Lysate assays. Asthma, atopy, and BHR status of each child were also assessed at ages 7–10 and 11–14.Alternaria or Cladosporium sensitization. The likelihood of BHR almost doubled with unit increases in dust beta-glucan in asthmatic children. In children without asthma, exposure to high beta-glucan levels at age 7–10 also elevated risk for BHR in adolescence . New-onset atopic asthma was twice more likely following high beta-glucan exposure in children without asthma but the association did not reach statistical significance. No associations were evident with concurrent asthma phenotype at age 7–10 or non-atopic asthma at age 11–14.At age 7–10, beta-glucan dust levels in the home were associated with persistent atopic asthma at age 11–14 , independent of endotoxin exposure, and These findings implicate home beta-glucan exposure at school-age as a risk factor for persistent atopic asthma and new-onset BHR. The higher prevalence of BHR in urban adolescents may be propagated by this home exposure. Asthma is one of the most prevalent chronic respiratory disorders, affecting over 2 million individuals in Canada Indoor mould has been self-reported to be present in an inordinately high percentage of homes of asthmatic children Beta--d-glucan (beta-glucan) is a glucose polymer present in fungal cell walls In summary, home environment exposures, in particular to fungal beta-glucan, have been understudied as determinants of adolescent asthma. Using data from the population-based Study of Asthma, Genes, and Environment (SAGE) cohort, the primary aim of our investigation was to determine if exposure to beta-glucan in house dust at school-age was associated with the development and persistence of asthma and its phenotypes by the age of 11–14. Outcomes included the common phenotypes of atopic and non-atopic asthma, as well as BHR.The SAGE study was approved by the University of Manitoba Human Research Ethics Board. Informed consent from parents and assent from their children were obtained at all recruitment stages.This was a planned, longitudinal follow-up of a nested case-control study of children in the 1995 SAGE birth cohort to study home environmental risk factors for asthma development in adolescence. This cohort was created from healthcare registry records of all children born in the province of Manitoba, Canada. Details of the study design for the SAGE cohort and nested case-control study have been published Alternaria, Cladosporium, Penicillium, house dust mites, cockroach, cat, dog, feathers and peanut). Atopic asthma was defined as a positive skin test for any allergen in the presence of diagnosed asthma; non-atopic asthma represented absence of sensitization to these allergens. BHR was determined using the Cockcroft method for the methacholine challenge test on the basis of a PC20 value of less than 8 mg/mL th percentile for age and gender) from the mean of 3 height and weight measurements using CDC growth charts At ages 7–10 and ages 11–14, children were assessed by a pediatric allergist to diagnose asthma, according to Canadian Asthma Consensus guidelines Beta-glucan levels in collected dust samples were measured with the Glucatell assay , a modified Limulus Amebocyte Lysate (LAL) assay. Factor C, originally used for endotoxin detection, was replaced by Factor G, allowing for (1→3)-β-D-glucan detection and avoiding false positive results from cross detection. The Glucatell assay predominantly measures fungal glucans but can also detect glucans from plants sources A 5 mg extraction of each dust sample was diluted with 1 mL 0.3N Sodium Hydroxide (NaOH) and shaken at room temperature for one hour. The LAL and chromogenic substrate solutions were then added. After being placed on an incubating plate reader for 20 minutes at 37°C, the reaction was stopped by adding sodium nitrite, followed by ammonium sulfamate and N-1-Napthyl-ethylenediamine dihydrochloride. To quantify beta-glucan, the absorbance of the sample was measured with a spectrophotometer and compared to the absorbance of a standard curve. A log-transformed measure for beta-glucan levels was tested in prevalence models since beta-glucan was found to be log-normally distributed. To accommodate smaller sample size in incidence models, a binary format of the beta-glucan measure was implemented, using the median of 36.81 as the cut-off value. Log-transformed endotoxin levels were included in analyses to account for co-occurrence with beta-glucan in home dust Alternaria, Cladosporium, Penicillium), family history of asthma, parental smoking, overweight and gender were tested in regression models. Confounding variables were retained in models according to statistical significance at a p<0.05 value and the “10% change in estimate rule,” whereby variables not found to be statistically significant but which changed the effect of beta-glucan by 10% or more were also included in the final model Using ordinary logistic regression, the likelihood  for BHR, and prevalent and incident asthma and atopic asthma was determined for dust beta-glucan levels. Based on the adolescent asthma literature Alternaria, 14% were sensitized to Cladosporium, 3.6% were sensitized to Penicillium) and 23% had a paternal history of asthma. The majority (94%) of parents had completed high school and almost one third were smokers. 57% of children lived in urban areas and still resided in their birth home. Any report of visible mould confirmed by a home visit was found in 50%, wall-to-wall carpeting in 51% and previous water damage in 46% of homes. Mean beta-glucan concentrations varied by season, from 36.58 mg/g in December-February and 53.90 mg/g in March-May to 63.08 mg/g in June-August and 79.38 mg/g in September-November. One quarter of homes contained beta-glucan levels in excess of 62.31 mg/g; more often these samples were taken in the fall/winter months  but were less likely to be asthmatic (26%) or live in urban areas (45%); no others differences were found  homes . The corI. Cross-sectional Analyses: Beta-Glucan Exposure and Asthma or BHR at Age 7–10Alternaria sensitization at age 7–10 was strongly associated with current asthma , atopic asthma  and BHR . Similarly, a positive skin prick test for Cladosporium  and Penicillium  were highly associated with atopic asthma. However, beta-glucan levels measured in house dust were not associated with asthma , atopic asthma , nonatopic asthma  or BHR  in unadjusted models or models adjusted for endotoxin, and Alternaria, Cladosporium or Penicillium at this age.Alternaria  or Cladosporium  or Penicillium  at age 7–10. Asthma prevalence at age 11–14 was unrelated to Penicillium sensitization . None of the other studied covariates  affected this association and were not retained in models  in children with existing asthma with each unit increase to dust beta-glucan levels . This stn models . Althougn models , this asAlternaria but not Cladosporium or Penicillium sensitization. The association was unaffected by other study covariates.High beta-glucan levels (> median of 36.81) in house dust doubled the risk for new-onset asthma in adjusted models in children without pre-existing asthma, but statistical significance was not attained , p<0.09.Alternaria sensitization at age 7–10, which independently increased the risk for atopic asthma almost 6-fold (p<0.0001), strengthened the association between beta-glucan and atopic asthma prevalence . Despite a stronger association between Cladosporium sensitization and subsequent atopic asthma, the association between beta-glucan and this asthma phenotype was unchanged. None of the other studied covariates affected this association  in asthmatic children with each unit increase in exposure to beta-glucan . Adjustmociation .In children without previous asthma (atopic or non-atopic) at age 7–10, a statistical association between beta-glucan and atopic asthma at age 11–14 was not present .Alternaria or Cladosporium sensitization at age 7–10 developed nonatopic asthma, it was not possible to run models adjusted for these covariates.Beta-glucan levels in house dust were not found to be significantly related to non-atopic asthma at age 11–14 in crude or endotoxin-adjusted models . Since no child with Alternaria sensitization, an independent risk factor for BHR, did not alter the strength of this association  sensitization.Independent of endotoxin presence, unit increases to beta-glucan in house dust at age 7–10 were associated with a 2-fold increased likelihood of prevalent BHR at age 11–14 in children with existing asthma  for each log unit increase in beta-glucan levels. Specifically, it was driven by the association with atopic asthma  since beta-glucan exposure was not associated with non-atopic asthma. A 2-fold association was found for new-onset asthma following high beta-glucan exposure levels in children without asthma at age 7–10 but it was not statistically significant. Cross-sectionally at age 7–10, beta-glucan exposure was unrelated to asthma phenotype. Though sensitization to any allergen at age 6 is a stronger determinant of unremitting asthma There are several additional important findings in this study. Beta-glucan in house dust at school age doubled the risk for subsequent BHR among children with asthma. BHR has been observed in asthmatic children exposed to high indoor beta-glucan levels in previous studies Beta-glucan levels were not obviously higher in homes with visible mould, self-reported by the parent and observed during a home visit, and visible mould was not statistically significant in our models. Poor correlation between self-reported visible mould or fungal spores, and beta-glucan levels has been reported by others AlternariaAlternaria is not a significant source of beta-glucan but co-exists with fungi that produce beta-glucan in house dust Alternaria's association with asthma and BHR suggest differing immunomodulatory pathways for each. Iossifova et al postulate that a low beta-glucan yet high allergenic protein content accounts for Alternaria's high allergic potential Cladosporium sensitization in our study. Since sensitization to Cladosporium in Manitoba children is almost as common as for AlternariaCladosporium in outdoor air may also be a source of sensitization, as reported in the Behbod et al study As others have found, atopic sensitization at age 7–10, in particular to The major strength of this study was temporal assessment between beta-glucan exposure at school age and subsequent adolescent asthma in a large number of children with and without asthma, as tested in incidence analyses and prevalence models. No association between beta-glucan and concurrent asthma at age 7–10 was observed, further providing evidence for its role in asthma development and persistence in adolescence. Since high beta-glucan levels co-existed with high endotoxin levels, all analyses were adjusted for endotoxin levels to parcel out the effect of beta-glucan. This adjustment often strengthened the association between beta-glucan and asthma or BHR. Found by others to have protective effects on asthma, wheeze Despite its many strengths, our study was limited in the following ways. It had no additional measures of environmental exposures such as air pollution or beta-glucan in school dust Our follow-up study of children with and without a genetic risk for asthma, found a risk for atopic asthma and BHR in adolescent children previously exposed to beta-glucan. Associations were found for exposure at age 7–10, indicating that beta-glucan in house dust is an important source of sensitization, even later in childhood. Replication of our findings in other populations is required. In the interim, allergen avoidance methods such as regular vacuuming and dry steam cleaning carpets can effectively reduce indoor dust


Studies in heterosexual HIV serodiscordant couples have provided critical evidence on the role of HIV treatments in reducing HIV transmission risk. However, there are limited data regarding the effect of treatment on HIV transmission in homosexual male couples. We examined features of male homosexual HIV serodiscordant relationships that may impact upon the design of HIV treatment and transmission studies.Data were from a prospective cohort study of HIV-negative homosexual men in Sydney, Australia. Men were followed up with six-monthly interviews and annual testing for HIV. Characteristics of men in HIV serodiscordant and seroconcordant relationships at baseline were compared, and a longitudinal analysis performed of rate of relationship break-up and of HIV incidence.n=79) had an HIV-positive partner. Most (80.8%) of these relationships were non-monogamous, and 36.7% of men reported recent unprotected anal intercourse (UAI) with casual partners. The rate of relationship break-up was 29.5 per 100 person-years. Half of men in serodiscordant relationships (49.4%) reported recent UAI with their regular partners. HIV incidence was 2.2 per 100 person-years. It was substantially higher in relationships of less than one year's duration (6.1 per 100 person-years) and in men who reported unprotected receptive anal intercourse with ejaculation with their regular partners (15.5 per 100 person-years).At baseline, 5.5% of participants (Levels of HIV transmission risk and incidence were high, particularly in early relationships. Rates of relationship break-up were high. These data suggest that studies of HIV treatments and transmission in homosexual serodiscordant couples should focus on early relationships so as not to underestimate risk, and sample sizes must allow for high rates of relationship break-up. HIV Prevention Trials Network (HPTN) 052 Study, confirmed that heterosexual couples randomized to immediate treatment of the HIV-positive partner had a 96% reduction in HIV transmission to the HIV-negative partner [Longitudinal studies in heterosexual HIV serodiscordant couples have been critical in delineating the role of the treatment of HIV-positive partners with antiretroviral therapy (ART) in reducing the risk of HIV transmission within these couples. Observational studies of such couples reported that HIV treatment of HIV-positive partners was associated with greatly reduced transmission . In 2011 partner ,4. Given partner , resultsPartners of people on ART – a New Evaluation of the Risks (PARTNER) Study in the United Kingdom and Europe [Internationally, while there has been some focus on the use of pre-exposure prophylaxis (PrEP) in homosexual men ,9, only d Europe . The intd Europe .Since HIV treatment of the HIV-positive partner has been proven to be highly effective in preventing HIV transmission to the HIV-negative partner in heterosexual serodiscordant couples, it is generally agreed that a similar randomized trial in homosexual male couples is not ethical ,11. RathHealth In Men Study (HIM) from a wide range of community-based settings in Sydney, Australia between June 2001 and December 2004, and followed until 2007, as described in detail elsewhere [Participants were recruited into the lsewhere . Men werParticipants underwent two interviews each year, reporting whether they had a primary regular sexual partner (defined by participants) currently and in the last six months, and the HIV serostatus of regular partners. Men who reported that they had an HIV-positive regular partner during the past six months were defined as being in a serodiscordant relationship. During follow-up, participants reported whether they were still in these same sexual relationships, if they had new regular partner/s or if they no longer had regular partner/s, as well as their perception of the HIV viral load of their HIV-positive partner (if applicable). Participants reported details of sexual behaviour with their regular partner/s and with other men, including the number of episodes of UAI separately for regular and for casual partners, for the insertive and receptive positions, and by HIV status of these partners . In addition, for receptive UAI, they reported episodes separately by whether or not ejaculation occurred inside their rectum. The reported types of UAI with the regular partner were regrouped for analysis according to their escalating risk of HIV infection, that is, no UAI; insertive UAI only; receptive UAI with withdrawal ; and receptive UAI with ejaculation . Men were tested for HIV antibodies annually.n=1165), and excluded men who during follow-up never had a primary partner or had a primary partner whose HIV status the participant did not know (n=262). Cox regression was used to determine hazard ratios for categories of different HIV risk. For categories in which zero events were observed, incidence rate ratios and 95% confidence intervals were calculated using exact Poisson regression. Methods of ascertainment of HIV seroconversion in HIM have been described elsewhere [p-value for overall trend was reported for continuous or ordinal variables, and p-value for heterogeneity was reported for categorical variables.Statistical analyses were conducted using Stata . Characteristics of men in serodiscordant relationships and seroconcordant relationships at baseline were compared using logistic regression. The break-up rates of the serodiscordant relationships and seroconcordant relationships were compared in a longitudinal analysis, and predictors of relationship break-up for men in serodiscordant relationships were examined with Cox regression. HIV incidence per person-year was calculated in participants with HIV-positive primary partners and compared with men with HIV-negative primary partners . Having lsewhere . All regn=139, 9.74%). The cohort has been described in detail elsewhere [A total of 1427 HIV-negative participants were enrolled and the median age at enrolment was 35 years (range=18–75 years). The vast majority (95.2%) of participants self-identified as gay or homosexual. Follow-up interviews at one and two years were attended by 87 and 81% of participants, respectively, and the most common reason for loss-to-follow-up was relocation from Sydney (lsewhere .n=946) of participants reported having a primary regular partner: of these, 8.4% (n=79) reported an HIV-positive primary partner; 70.6% (n=668) an HIV-negative primary partner; and 21.0% (n=199) had a primary partner of unknown HIV serostatus. Men in serodiscordant relationships were not different from men in seroconcordant relationships with regard to age (p-trend=0.246), primary partner's age (p-trend=0.368) or length of relationship (p-trend=0.156). The majority of men in serodiscordant and seroconcordant relationships had had sex with at least one other partner in the previous six months, and the proportion did not differ between the two groups . Nearly three-quarters  of men in serodiscordant relationships had been tested for HIV in the last six months, compared to half  of men in seroconcordant relationships (p<0.001).At baseline, 66.3% (n=47) and 76.4% (n=510) of the men in seroconcordant relationships reported UAI in the previous six months (p=0.001). UAI with regular partner(s) in the previous six months was reported by 49.4% (n=39) and 72.0% (n=481) of men in serodiscordant and seroconcordant relationships respectively (p<0.001). By contrast, UAI with casual partner(s) in the previous six months was reported by 36.7% (n=29) and 21.4% (n=143) of men in serodiscordant and seroconcordant relationships (p=0.003).At baseline, more than half of the men in serodiscordant relationships  reported the partner's viral load to be undetectable (defined as under 500 copies per mL) and 26.6% (n=21) reported it to be detectable, one-third did not know the partner's viral load . Participants who perceived that their partner's viral load was detectable or unknown were non-significantly less likely to report UAI with their partner in the previous six months .Men in serodiscordant relationships reported the viral load of their HIV-positive partner at baseline. While 39.2% (p=0.416). In men in serodiscordant relationships, those in longer relationships were less likely to break-up compared to men in relationships of less than six months at baseline , and this was not statistically different from men in seroconcordant relationships . In these partnerships, incidence was highest among men who reported at least one episode of receptive UAI with ejaculation with that regular partner .HIV incidence among men with known-HIV-status primary regular partners was examined in 1165 men over 3331.5 person-years . Twenty-nine of these men seroconverted, and the overall HIV incidence was 0.87 per 100 person-years. Those who reported an HIV-positive primary partner had an HIV incidence of 2.20 per 100 person-years, compared to 0.71 per 100 person-years in those who had HIV-negative primary partners only . HIV incidence was much higher in men who were in the first year of the serodiscordant relationship (6.1 per 100 person-years), and incidence decreased markedly in men reporting longer relationships  in the previous six months. Rates of relationship break-up were high, at 29.5 per 100 person-years, but this was not different to rates of relationship break-up in seroconcordant relationships. HIV incidence in serodiscordant relationships was 2.20 per 100 person-years, and was much higher in the first year of the relationship, and in men who reported receptive UAI in their relationship. Most men did not know their partner's viral load, and we documented no HIV seroconversions in those who reported that their partner had undetectable viral load.Our data highlight several challenges in conducting prospective research on the role of ART in decreasing HIV transmission in homosexual male couples. Key issues include whether the prevalence of serodiscordant relationships is sufficient to achieve required sample sizes, the high rates of non-monogamy and break-up and how the HIV incidence in homosexual serodiscordant couples may affect sample size requirements.In our community-based sample, 5.5% of HIV-negative homosexual men were in a HIV serodiscordant relationship (8.4% of men in relationships). This suggests that in the Australian state of New South Wales alone, there would be nearly 4000 HIV-negative men in serodiscordant relationships at any given time . Thus, tHPTN 052, approximately 5% of HIV-negative participants reported more than one partner in the previous three months. However, non-monogamy is likely to have been underreported in that study as only 71.8% of the incident infections were phylogenetically linked to the index HIV-positive partner [Non-monogamy is an important concern for studies of HIV transmission in serodiscordant couples. In  partner –19. Thes partner ,20, phyl partner .HPTN 052, around 3–5% of the couples in each arm ended their relationship during follow-up [Relationship break-up is a problem for any longitudinal study of couples . In HPTNollow-up . Inverseollow-up ,25 and pThe incidence of HIV of men in serodiscordant couples in our study was high (2.2 per 100 person-years), and was about 3-fold higher than in other men. The high incidence rate was unsurprising given the high levels of UAI, including receptive UAI, that were reported. For those who reported a serodiscordant relationship of one year or less, the HIV incidence was much higher (at around 6 per 100 person-years) than in those who reported longer relationships (around 1 per 100 person-years), demonstrating that the riskiest period for HIV-negative men in serodiscordant relationships is the first year of the relationship. This may be due to the relatively higher frequency of sex in newer relationships ,27. In aHIM study's focus on HIV-negative individuals, the viral load of the HIV-positive partner was reported by the respondent and may have been inaccurate. Second, the data were collected when condom use was virtually the only HIV prevention method promoted to gay men, and certainly prior to any widespread discussion of HIV treatment as prevention or PrEP in the gay community. There is potential that the results of studies of ART-based prevention may have led to various changes in the attitudes and behaviour of men in homosexual serodiscordant couples. For example: explicit communication about viral load within couples may now be more common; viral load may be utilized to a greater extent in decision-making about condom use; and greater uptake of HIV treatment amongst HIV-positive men may impact upon the incidence rate within homosexual serodiscordant couples. Furthermore, although PrEP is not commercially available in Australia at the current time, PrEP demonstration projects have commenced in several cities. PrEP may affect studies on treatment as prevention: If HIV-negative partners take PrEP, the distinct risk reduction effects of treatment as prevention may become more difficult to assess. It is likely that larger sample sizes will be required, as well as careful monitoring of PrEP use throughout follow-up. However, despite these limitations, the analysis provides important insights regarding HIV-negative men in serodiscordant relationships and their implications for existing and future treatment as prevention research among gay men.This study had the strength of being community-based with a high rate of participant retention, and is one of very few reported prospective studies of homosexual male serodiscordant relationships. Our analysis had several limitations. First, due to the PARTNER Study in the United Kingdom and Europe [PARTNER, we are aware of only one other ongoing study on treatment as prevention in homosexual couples: the Opposites Attract Study, being conducted in Australia, Brazil and Thailand [Evidence regarding HIV treatment and transmission in homosexual male serodiscordant couples has been presented only on the interim analysis from the d Europe ,10, despThailand ,30. The


Autonomic nervous system balance can be significantly deteriorated during heart failure exacerbation. However, it is still unknown whether these changes are only the consequence of heart failure decompensation or can also predict development thereof. Objectives were to verify if simple, non-invasive autonomic parameters, such as baroreflex sensitivity and short-term heart rate variability can provide independent of other well-known clinical parameters information on the risk of heart failure decompensation in patients with left ventricular systolic dysfunction.In 142 stable patients with left ventricular ejection fraction ≤ 40%, baroreflex sensitivity and short-term heart rate variability, as well as other well-known clinical parameters, were analyzed. During 23 ± 9 months of follow-up 19 patients were hospitalized due to the heart failure decompensation (EVENT).2) were significantly associated with the EVENTs . EVENTs were also associated with other parameters, such as left ventricular ejection fraction, NYHA class, diuretic use, renal function, brain natriuretic peptide and hemoglobin level, left atrial size, left and right ventricular heart failure signs. After adjusting baroreflex sensitivity and low frequency power index for each of the abovementioned parameters, autonomic parameters were still significant predictors of hospitalization due to the heart failure decompensation.Pre-specified cut-off values of baroreflex sensitivity (≤2.4 ms/mmHg) and low frequency power index of heart rate variability (≤19 msSimple, noninvasive autonomic indices can be helpful in identifying individuals with increased risk of hospitalization due to the heart failure decompensation among clinically stable patients with left ventricular systolic dysfunction, even when adjusted for other well-known clinical parameters. According to literature, patients with heart failure are characterized by predominance of sympathetic activity and decreased vagal tone –3. Barorobjectives of the study were to verify if BRS and HRV indices can provide independent information on the risk of hospitalization due to heart failure decompensation in stable patients with LV systolic dysfunction, and whether this information is independent of other well-established clinical parameters.Therefore, exclusion criteria were: age <18 years, pacemaker rhythm including cardiac resynchronization therapy with successful resynchronization, NYHA functional class IV, permanent atrial fibrillation/flutter, permanent second- or third-degree atrioventricular block, type 1 diabetes mellitus, documented autonomic neuropathy (information based on patients records), poor general condition , and non-cardiologic comorbidities with potential unfavourable effect on survival.Between December 2009 and March 2012, 142 consecutive patients with chronic heart failure, presenting with typical clinical signs and symptoms of this condition  and LVEFMingograf 720C) and beat-to-beat non-invasive arterial blood pressure  were recorded continuously for 10 min during spontaneous breathing. The signals were acquired with a PC workstation, processed with a dedicated software ). In an event of potential drop-outs, the sample size was eventually set at 142 . The patients’ data were censored on the date of the end-point or last follow-up. Due to the lack of normal distributions, all the variables were expressed as medians , or numbers (n) and percentages (%). The quantitative characteristics of the EVENT_(+) and EVENT_(-) groups were compared with the Mann-Whitney U-test, and the qualitative data with the chi-square test or Yates’ chi-square test. The power and direction of relationships between pairs of selected variables were analyzed on the basis of the Pearson’s coefficients of linear correlation. The accuracy of ANS indices and other parameters as potential predictors of the study end-points was determined on the basis of area (AUC) under the receiver-operating characteristic (ROC) curve. An association between analyzed parameters and the end-point was assessed using the Cox univariate and multivariate proportional hazard models, after dichotomization of the measurements according to their cut-off values that maximized the hazard ratio (HR). For this purpose, we calculated HR for progressively increasing appropriate values comprised between the 20th and 50th percentiles (to have an adequate number of patients in each subgroup) and identified the point at which HR attained its maximum. The time course of the end-point, stratified according to the aforementioned cut-off values, was estimated using the Kaplan-Meier method, and the association between compared groups was estimated by the log-rank test. All the results were considered statistically significant at p≤0.05. The statistical analysis was conducted with STATISTICA 9.0  package and R 2.15.2 environment.The minimum sample size was estimated as Baseline clinical and demographic characteristics of the study group are presented in A total of 36 out of the 142 (25%) recordings used to calculate the BRS and HRV indices could not be analyzed due to large number of ectopic beats or presence of artifacts. As shown in R = 0.02, P = 0.81 and R = 0.07, P = 0.49 for EVENT_(+) and EVENT_(-), respectively). In turn, a significant linear correlation between BRS and LF values was observed ; on subgroup analysis this correlation turned out to be particularly strong in the case of the EVENT_(+) patients  group).We did not find significant linear correlations between BRS and LF values (i.e. the parameters that differed significantly between the EVENT_(+) and EVENT_(-) groups) and LVEF . BRS (AUC 66.5% [CI 45.8–87.2%]) and LF (AUC 64.0% [CI 43.8–84.2%]) were characterized by lower discriminatory powers.2, LVEF ≤ 25%, glomerular filtration rate (GFR) less than 60 ml/min, LA size > 45 mm and BNP ≥ 125 pg/ml. All these values, as well as NYHA class III, anemia, LV- and RV failure signs and diuretic use, turned out to be significantly associated with the incidence of the end-point on univariate Cox analysis  accurately identified the patients who were at increased risk of heart failure decompensation during nearly two-year follow-up. A significant association between mentioned above clinical markers  and the risk for heart failure decompensation was also confirmed.The observation that decreased BRS and LF may predict hospitalization due to heart failure decompensation in clinically stable patients with LV systolic dysfunction, even after adjusting for other well-known clinical parameters , is the principal finding of our study. The cut-off values determined in this study  could not be analyzed in 25% of included patients, which narrows even more the group of patients. This, unfortunately, is a known problem of ANS tests described in published documents in this field. Furthermore, we did not analyze neither invasive hemodynamic parameters or dynamics of the ANS indices before reaching the end-point, nor the ANS parameters at the moment of patients’ hospitalization due to the heart failure exacerbation. All these data would be useful for detailed understanding of pathophysiological mechanisms underlying the hereby reported phenomena. Unfortunately, so far, it has been difficult to unequivocally determine the pathophysiological mechanism linking ANS parameters and the factors leading to the decompensated phase of heart failure and hospital admission of patients.We are well aware of potential The results of our study suggest that simple noninvasively obtained parameters of ANS activity, such as BRS and short-term LF, can be helpful in identifying individuals at increased risk of hospitalization due to heart failure decompensation among clinically stable patients with LV systolic dysfunction, even when adjusted for other simple clinical parameters, such as LVEF and NYHA class. These findings substantiate further research during which patients with systolic LV dysfunction would be subjected to repeated BRS and HRV analyzes in order to study the dynamics of changes in ANS activity and to identify short- and long-term predictors of heart failure decompensation.


Few studies have investigated the 24-hour symptom profile in patients with COPD or how symptoms during the 24-hour day are inter-related. This observational study assessed the prevalence, severity and relationship between night-time, early morning and daytime COPD symptoms and explored the relationship between 24-hour symptoms and other patient-reported outcomes.1), dyspnoea , health status (COPD Assessment Test), anxiety and depression levels , sleep quality  and physical activity level  were recorded.The study enrolled patients with stable COPD in clinical practice. Baseline night-time, early morning and daytime symptoms (symptom questionnaire), severity of airflow obstruction . Symptom severity was comparable for each period assessed. Overall, in the week before baseline, 56.7% of patients had symptoms throughout the whole 24-hour day (3 parts of the day); 79.9% had symptoms in ≥2 parts of the 24-hour day. Symptoms during each part of the day were inter-related, irrespective of disease severity .Early morning and daytime symptoms were associated with the severity of airflow obstruction (p < 0.05 for both). Night-time, early morning and daytime symptoms were all associated with worse dyspnoea, health status and sleep quality, and higher anxiety and depression levels . In each part of the 24-hour day, there was also an association between symptoms and a patient’s physical activity level (p < 0.05 for each period).More than half of patients experienced COPD symptoms throughout the whole 24-hour day. There was a significant relationship between night-time, early morning and daytime symptoms. In each period, symptoms were associated with worse patient-reported outcomes, suggesting that improving 24-hour symptoms should be an important consideration in the management of COPD.The online version of this article (doi:10.1186/s12931-014-0122-1) contains supplementary material, which is available to authorized users. Despite being preventable and treatable, chronic obstructive pulmonary disease (COPD) is associated with considerable morbidity and mortality ,2 and itCOPD symptoms have been reported to vary throughout the day -12. In cIn a pan-European, observational study, patients’ perception of the variability of their breathlessness was associated with both the severity of breathlessness and frequent exacerbations , while tIn this observational study, we investigated the prevalence and severity of night-time, early morning and daytime symptoms in patients with stable COPD being treated in clinical practice and explored the relationship between symptoms in each part of the 24-hour day. Additionally, to better understand the relationship between 24-hour symptoms and other aspects of a patient’s overall well-being, we assessed their association with the severity of airflow obstruction and other patient-reported outcomes, including self-perceived dyspnoea, health status, anxiety and depression levels, sleep quality and physical activity level.This was a multinational, non-interventional, observational study conducted in 85 clinical practice centres (pulmonologists outpatients and primary care) across Denmark, France, Germany, Italy, The Netherlands, Spain, Sweden and UK  spirometric classification ,  the week before baseline and (ii) a typical week in the month before baseline . In addition, the questionnaire also contained questions related to sleep disturbances, rescue medication, anxiety due to symptoms, limitation of activities due to symptoms and concentration levels. The questionnaire consists of three parts (one part for each period during the 24-hours) and includes 13 items for night-time symptoms, ten items for morning symptoms and ten items for daytime symptoms. Night-time corresponds to the time from when the patient goes to bed until they get out of bed to start the day; morning is the time from getting out of bed until approximately 11 am; and daytime is from approximately 11 am until the patient goes to bed. Patients were asked about the frequency of symptoms related to breathlessness, coughing, bringing up phlegm or mucus, chest tightness, chest congestion and wheezing during each period. Patients were also asked about the overall severity of their night-time, early morning and daytime symptoms during the last week; symptom severity was scored as 1 (no symptoms); 2 (mild); 3 (moderate); 4 (severe) or 5 (very severe).Dyspnoea was assessed using the modified Medical Research Council (mMRC) scale  with patPrimary endpoints in the study were the prevalence, severity, and inter-relationships for night-time, early morning and daytime symptoms at baseline . To further explore the relationship between 24-hour symptoms and other aspects of COPD that affect patients’ well-being, secondary endpoints included the relationship between night-time, early morning and daytime symptoms and severity of COPD, dyspnoea severity, health status, levels of anxiety and depression, sleep quality and physical activity levels.All analyses were performed using the full analysis set, which comprised all patients who fulfilled the eligibility criteria and who completed the Night-time, Morning and Daytime Symptoms of COPD questionnaire. The data were analysed using only the available data for each outcome. Descriptive data are reported as mean ± standard deviation (SD) or percentages, as appropriate. The relationship between symptoms in each part of the day and baseline characteristics or patient-reported outcomes was assessed using univariate analysis. The relationship between symptoms in each part of the day, symptoms and airflow limitation, symptoms and comorbidities and symptoms and physical activity level was assessed using a chi-squared test. The relationship between night-time, early morning or daytime symptoms and dyspnoea, health status, anxiety and depression levels, and sleep quality was assessed using a Wilcoxon rank sum test. All statistical tests were two-sided and used a 5% significance level; there was no adjustment for multiplicity. All statistical analyses were performed using SAS .A sample size of 680 patients offered a maximum margin of error (minimum precision) of 4% for estimating the percentage of patients with night-time, early morning and daytime symptoms, considering maximum indetermination (p = 50%) and a confidence level of 95%. Anticipating that approximately 5% of patients would have missing data or a major protocol violation, the final sample size was set at 720 patients.2-agonists [LABA], long-acting muscarinic antagonists [LAMA] plus inhaled corticosteroids), with or without a phosphodiesterase 4 (PDE4) inhibitor . In addition to COPD, 79.4% of patients had a comorbid medical condition; 45.1% of patients had a diagnosis of hypertension and 33.7% had cardiovascular disease. Based on physical activity level, 30.0% of patients were assessed as being sedentary, 38.1% as moderately active and 31.4% as active at baseline.Of 743 patients who enrolled in the study and had a baseline visit, 727 were eligible for inclusion in the full analysis set. Demographics and baseline characteristics are shown in Table The prevalence of COPD symptoms in each part of the 24-hour day is shown in Figure Patients’ assessment of the severity of their night-time, early morning and daytime symptoms is shown in Table When individual symptoms were assessed, symptoms related to breathlessness were most common (71.4% of patients) followed by coughing (65.9%), bringing up phlegm or mucus (59.6%), wheezing (41.4%), chest tightness 32.9%) and chest congestion (23.4%). The frequency and pattern of each individual symptom varied throughout the 24-hour day . The relationships between night-time, early morning and daytime symptoms were maintained for all symptom combinations, irrespective of the severity of airflow limitation .The overall proportion of patients with any COPD symptom and the prevalence of night-time, early morning and daytime symptoms, according to COPD severity (based on airflow limitation) are shown in Figure There was a significant relationship between night-time, early morning and daytime symptoms and the severity of self-perceived dyspnoea . There was also a significant relationship for the number of parts of the 24-hour day when patients experienced symptoms and physical activity levels (p = 0.006). A higher proportion of patients who were sedentary had symptoms throughout the whole 24-hour day compared with patients who were active .Mean CAT, HADS anxiety and depression, and CASIS scores according to each 24-hour symptom combination are shown in Figure In this observational study, more than half of patients reported experiencing COPD symptoms throughout the whole 24-hour day, despite receiving ongoing treatment for their COPD and almost 80% of patients had symptoms during at least two parts of the 24-hour day. While early morning and daytime symptoms were most frequent, night-time symptoms were also very common and almost two-thirds of patients experienced at least one night-time symptom during the week before baseline. Importantly, any symptoms in the early morning, daytime or night-time were associated with worse outcomes across a range of patient-reported measures including more severe dyspnoea, higher anxiety and depression levels and worse health status and sleep quality.The observation that a large majority of patients experienced symptoms during at least two parts of the 24-hour day is consistent with results from a recent real-world study in almost 1500 patients. The study by Roche et al. showed that most patients had symptoms during the daytime and night-time and only 34% of patients experienced COPD symptoms in isolation during one part of the 24-hour day . HoweverThere is no objective definition of ‘night-time symptoms’ in patients with COPD, and it has been suggested that night-time symptoms may be under-reported by physicians or may not be reported by patients . The resEarly morning symptoms have been reported to be most problematic for patients with COPD and can significantly impact on daily activities -12 and wIn each part of the 24-hour day, symptoms were associated with worse dyspnoea, health status, higher anxiety and depression levels, and greater sleep impairment. These are all outcomes that can impact on patients’ daily living and overall well-being. The difference in CAT scores between patients with and without symptoms in each period exceeded the estimated minimal clinically important difference (2 points) recently proposed , suggestOverall, our results support previous studies showing that symptoms during the morning and the night-time are independently associated with worse outcomes in patients with COPD ,13. COPDWhile these results demonstrate significant relationships between symptoms in each part of the 24-hour day and various aspects of patients’ well-being, the analyses do not take into account confounding factors such as disease severity or comorbid conditions, which may also impact on patient-reported outcomes. Furthermore, no causal relationship can be inferred from the analyses as this was an observational study. Further investigation of the specific relationship between symptoms in each part of the 24-hour day and each outcome is required to establish whether symptoms are independently associated with the outcome, irrespective of underlying disease. While this study enrolled patients with mild to very severe COPD, only patients being treated in clinical practice  were assessed. As such, the relevance of these observations for the wider population of patients with COPD, including those with undiagnosed COPD, requires further consideration.The results of this study demonstrate that despite receiving treatment for COPD, more than half of patients continued to have symptoms throughout the whole 24-hour day, including during the night-time and early morning periods. The relationship between night-time, early morning and daytime symptoms was observed irrespective of the severity of airflow obstruction. Patients with symptoms during any part of the 24-hour day also had significantly worse outcomes across a range of measures that impact on daily living, including health status, anxiety and depression levels and sleep quality compared with patients without symptoms. This suggests that current approaches to managing COPD may not adequately control symptoms, which can impact on a patient’s overall well-being. Newer therapies, including long-acting bronchodilators that are administered twice-daily or ultra-long-acting bronchodilators, may be useful in improving symptom control during the night-time, whereas those with a rapid onset of action may have advantages in controlling early morning symptoms. It is important for physicians to manage patients’ symptoms throughout the 24-hour day, even in those with mild airflow obstruction.


Immigrants to the United States are more likely to be diagnosed with human immunodeficiency virus (HIV) infection compared with native-born persons. Navigating access to healthcare in the United States can be challenging for foreign-born persons, and HIV treatment outcomes may be suboptimal for these persons. We compared characteristics of and assessed disparities in clinical outcomes of foreign-born persons in care for HIV in the United States.The Medical Monitoring Project is a complex sample, cross-sectional survey designed to be nationally representative of HIV-infected adults receiving medical care in the United States.Using data from 2009, 2010, and 2011, we conducted descriptive analyses and multivariable logistic regression to assess associations between foreign-born status and antiretroviral therapy (ART) prescription, and between foreign-born status and viral suppression.In all, 13.4% of HIV-infected persons were self-identified as foreign-born; the most common regions of birth were Central America and Mexico (45.4%) and the Caribbean (16.0%). Nearly 90% of foreign-born persons were diagnosed with HIV after entry into the United States. Compared with US-born persons, foreign-born persons were more likely to be younger, Hispanic, less educated, and uninsured. The prevalence of ART prescription  was not significantly different between foreign-born and US-born persons. A higher percentage of foreign-born persons achieved viral suppression compared with US-born persons .No major disparities in ART prescription and viral suppression were found between foreign-born and US-born HIV-infected persons receiving medical care, despite higher percentages being uninsured. In general, foreign-born persons in the United States are less likely to access routine healthcare, less likely to have health insurance, and report lower levels of satisfaction with the healthcare received.2 Retention of HIV-infected immigrants in care may be especially challenging for those living in marginalized communities, those emigrating from countries where HIV denialism is prevalent, and those whose social or religious communities view HIV infection as a moral fault. United States immigration policies classified HIV-positive status as an inadmissible condition for entry of immigrants and refugees from 1991 to 2009.3 Although a diagnosis of HIV infection was eliminated as an exclusionary condition in 2010, fear of negative repercussions from diagnosis or disclosure of HIV status within foreign-born populations may remain. Lowered access to, utilization of, and satisfaction with healthcare provision can lead to suboptimal clinical outcomes for any HIV-infected person; these factors may be especially impactful on clinical outcomes for new immigrants.In the United States, immigrants are more likely to be diagnosed with human immunodeficiency virus (HIV) infection than native (US-born) persons,6 Most have not observed statistically significant differences in measures of disease progression or viral suppression.7 Another study classifying subjects by documented citizenship or alien status found no differences in viral suppression between undocumented Hispanics receiving care as compared to documented Hispanics and whites.8 While local studies are important for assessing regional health care provision and needs, these analyses have limited sample sizes for foreign-born and may have been insufficiently powered to detect differences between populations. Additionally, 2 studies that have explored time of diagnosis (before or after migration) were limited to specific regions.9The few comparisons of clinical outcomes between foreign-born and US-born have been limited to specific geographic regions or ethnic/racial groups. These studies have found similar proportions of foreign-born persons receiving antiretroviral therapy (ART) as US-born.We used data from a survey specifically designed to be nationally representative of HIV-infected persons receiving medical care to describe characteristics of foreign-born HIV-infected persons receiving medical care and to explore clinical outcomes of ART receipt and viral suppression achieved by foreign-born HIV-infected persons as compared with their US-born counterparts. This study provides the first national-level description of foreign-born HIV-infected persons in care in the United States and an evaluation of clinical outcomes of foreign-born persons as compared with US-born persons on a national level.10 MMP utilizes a 3-stage, complex sampling design in which US states and territories are sampled, followed by facilities providing outpatient HIV medical care in those jurisdictions, then HIV-infected adults (aged 18 years and older) receiving care in those facilities. We used data from 2009, 2010, and 2011 MMP data collection cycles, including information on adults with at least 1 HIV medical care visit to participating facilities during January to April 2009 (2009 cycle), January to April 2010 (2010 cycle), and January to April 2011 (2011 cycle). Data were collected from June 2009 through May 2012 using face-to-face or telephone interviews and medical record abstractions. MMP protocols are publicly available, and further details regarding sampling locations and methodology are available in yearly surveillance summaries.12 The MMP data sets are not publicly available.The Medical Monitoring Project (MMP) is a surveillance system designed to produce nationally representative, cross-sectional estimates of behavioral and clinical characteristics of HIV-infected adults receiving medical care in the United States.The Centers for Disease Control and Prevention's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention has determined the MMP to be a nonresearch public health surveillance activity used to guide disease control programs and policy; therefore, it was not reviewed by a federal institutional review board. Participating facilities obtained local institutional review board approvals as required, and informed consent was obtained from all interviewed participants.All sampled states and territories participated in the MMP. Facility response rates were 76% (461/603) in 2009, 81% (474/582) in 2010, and 83% (473/570) in 2011. Approximately 50% of persons sampled from these facilities completed an interview and had their medical records abstracted , with 13194 patients sampled over 3 cycles. Patients were not excluded from sampling if they had participated in previous data-collection cycles . Foreign-born status was missing for 4 patients; these patients were excluded from the analysis, leaving a total of 13190 patients in our dataset. A specific country of origin was missing for an additional 2 patients who were self-identified as foreign-born; these patients were included in analyses except when region of origin was a variable.13 No imputation was made for refusals to provide information on country of birth. Covariates included sociodemographic characteristics and self-reported variables of time since HIV diagnosis, healthcare coverage, age at migration (if foreign-born), time in the United States since migration, sexual risk behavior, drug and alcohol use, homelessness and incarceration, and racial/ethnic category.Two outcome variables were explored independently: prescription of ART and achieving viral suppression. Prescription of ART was defined as any record of ART prescription in the 12 months before interview. Viral suppression was defined as undetectable or <200 copies/mL for the most recent measure. The main exposure variable was foreign-born status. Participants were considered foreign-born if they listed a country or territory of birth other than the United States or Puerto Rico. Geographic regions were defined as per recommendations of the United Nations Statistics Division, with Central America inclusive of Mexico.14Time of diagnosis (before or after migration) was calculated using self-reported time since diagnosis and time in the United States. Service needs were defined as unmet if at least 1 ancillary service need was unmet in the past year. Consistent care was defined as receipt of 2 or more CD4+ T-lymphocyte cell (CD4) count measures within the past year; this measure was chosen to align with the standard of care over the time period of data collection in this study. Case management service need was defined as unmet if service was needed but not received during the past year. Poverty level was defined using standard federal thresholds based on yearly income and number of household dependents.15 All analyses accounted for complex sample design and unequal selection probabilities by using survey procedures in SAS 9.3  and SUDAAN 10.0.1 .The MMP collected information on all sampled patients and facilities, including sex, age, race, length of time since diagnosis, and facility's HIV patient load, and was able to compare respondents and nonrespondents. Data were then weighted according to these analyses to minimize nonresponse bias.Absolute numbers and weighted frequencies were calculated for demographic, clinical, and behavioral characteristics. Associations between characteristics and foreign-born status were evaluated using a Rao-Scott chi-square test. Logistic regression analyses were conducted independently for both outcomes of interest . Because certain characteristics were only applicable to foreign-born persons  and these characteristics might moderate the effect of being foreign-born, separate logistic regression analyses were conducted for the association between each outcome variable and foreign-born status, categorized by these characteristics.P ≤ 0.05). Our criterion for a confounder to be included in the final multivariable model was any potential confounder that caused 10% or more change on the association . A priori variables were not forced into models if they did not meet this criterion. Univariate logistic regression models using the binary foreign born variable as the exposure of interest and either ART or viral suppression as the outcome proceeded to multivariable logistic regression models whether crude associations were significant (P < 0.10) or not. Independent models were also constructed for foreign-born as a nonbinary variable, with separate models to consider foreign-born by region of birth, age at migration, diagnosis before or after migration, and time in the United States; for these models, multivariable logistic regression models were only constructed if crude associations were significant (P < 0.10).Final multivariable models were developed separately for each binary outcome, ART prescription, and viral suppression. Current age, sex, and race/ethnicity were chosen as a priori potential confounders because we expected these might be related to both foreign-born status and outcomes. Race/ethnicity was not included as a potential confounder in analyses in which foreign-born were categorized by region, because region of origin will, in some cases, define race/ethnicity . Additional variables, including education level, poverty level, healthcare coverage, time since diagnosis, receipt of consistent care, categorization of disease severity, identified sexual risk factors, unmet service needs, and unmet case management needs were selected as potential confounders if associated with both the outcome for that model and the exposure for that model  were foreign-born. A total of 126 unique countries or territories were identified. Mexico was most frequently listed, followed by Cuba and Haiti  assessing the association of foreign-born status and receipt of ART prescription are shown in Table P = 0.02) as compared with US-born persons or those migrating from other regions. When foreign-born persons were categorized by age at migration, those who migrated as adults (≥18 years of age) achieved viral suppression in significantly higher proportions than US-born or those who migrated at younger ages . Similarly, foreign-born persons living in the United States for 10 or more years achieved viral suppression in higher proportions than their US-born counterparts or those more newly arrived in the United States .Prevalence ratios for assessing the association of foreign-born status and viral suppression are shown in Table This analysis presents the first nationally representative characterization of HIV-infected foreign-born adults receiving medical care in the United States and the first to directly characterize time of diagnosis as before or after migration. There was no evidence that on a national level, foreign-born persons are prescribed ART either more or less than US-born persons; this result was consistent in all models. A slightly higher proportion of foreign-born persons achieved viral suppression as compared with US-born persons. Additionally, several subgroups achieved viral suppression in slightly higher proportions, including foreign-born persons who migrated as adults, foreign-born persons who had lived in the United States for 10 or more years, and foreign-born persons from Mexico.16 as compared with the 13.4% foreign-born in the HIV-infected patient population in this study, with a minority (17.3%) having lived in the United States for less than 10 years. Our foreign-born participants reflect the multiplicity of countries from which immigrants and migrants arrive in the United States, although foreign-born for some regions were over or under-represented as compared with national estimates for foreign-born persons residing in the United States. Among the MMP participants, 45.4% were born in Central America (including 29.0% from Mexico), 16.0% in the Caribbean, 10.3% in Africa, 7.9% in Asia, and 11.1% in South America. Foreign-born HIV-infected persons from Mexico represented a proportion of HIV-infected individuals in MMP, which was similar to the ACS estimate that 29.3% of all foreign-born living in the United States are from Mexico; higher percentages of foreign-born persons from the Caribbean and Africa and lower percentages of foreign-born persons from Asia and the Middle East were observed in the MMP as compared with the ACS.16The most recent American Community Survey (ACS) estimated that 12.9% of the total population of the United States are foreign-born persons, with the majority (65.3%) having lived in the United States for less than 10 years,7 less well-educated,5 less likely to report injection drug use,7 and less likely to have health insurance.6 We did not see differences in the proportions of male and female foreign-born HIV-infected patients compared with those who were US-born. Findings in previous studies seem to be influenced by region of birth of the study population. For example, in populations with mixed origins or in which foreign-born originated exclusively from Africa, foreign-born persons infected with HIV were less likely to be male than US-born persons infected with HIV.18 However, in Hispanic/Latino populations, foreign-born persons infected with HIV were more frequently male.8 Additionally, we did not find any differences in the proportions of foreign-born and US-born persons who reported male-to-male sexual contact as a mode of exposure to HIV; this finding is in contrast to numerous studies reporting that foreign-born persons infected with HIV are less likely to report male-to-male sexual contact as a mode of exposure.19 We believe that our analysis, based on a nationally representative sample of HIV-infected adults, addresses some of the limitations inherent to generalizing results from studies conducted in geographically limited populations in the United States, such as in single cities or states.General demographic features of foreign-born HIV-infected adults receiving medical care in our study are consistent with previous reports from specific regions of the United States and from origin-specific groups of foreign-born HIV-infected persons. Similar to previous reports, we found that foreign-born persons were younger than their US-born counterparts,16 Higher proportions of foreign-born HIV-infected persons were male (74.0% vs 49.1%), living at or below poverty level (47.4% vs 18.8%), and uninsured (37.7% vs 34.3%) as compared with foreign-born persons in the general US population. These differences might reflect factors that increase a person's risk of HIV infection  or might be associated with living with HIV infection . Educational attainment levels were similar between foreign-born HIV-infected adults and foreign-born adults in the general US population.We found some key differences in our study population as compared with the demographic characteristics of the general population of foreign-born persons based on data from the ACS.20 we did not find that age was a confounder in our models of viral suppression. Yet, foreign-born persons were younger than native-born persons in our study and achieved viral suppression in slightly higher proportions than native-born persons. This suggests that other unmeasured characteristics not related to age may lead to these slightly better clinical outcomes in foreign-born persons. Those who self-select for migration may have (or acquire during migration) particular skills that are related to the skills required to successfully navigate health systems, adhere to therapy, and maintain health-seeking behaviors after diagnosis with HIV.Although viral suppression is achieved at higher proportions in older age groups within the United States,21 However, few studies have been able to definitively assess the proportion of HIV-infected persons who are diagnosed pre versus postmigration. Two studies of Hispanic/Latino immigrants have estimated, based on time reported in the United States and average time from infection to diagnosis, that HIV infection in this group of foreign-born persons is mainly due to HIV exposure after migration.23 Two studies have made estimates from individual-level data. Dennis et al5 found that 6.9% of southeastern-based Hispanic and Latino immigrants in care for HIV in their study were diagnosed before arrival in the United States, a figure similar to our estimate of 8.1%. For foreign-born persons residing in New York City and diagnosed with HIV during 2006 to 2012, Wiewel et al9 determined that 23% had probably acquired HIV outside the United States. Although our study evaluated location of diagnosis rather than location of acquisition, our results are consistent with that of Wiewel et al, considering lag time between infection and diagnosis. We estimated that 29.1% of foreign-born persons were diagnosed either before arrival or within the first 4 years in the United States.The act of migration may place some immigrant populations at higher risk of HIV infection than they would have faced in their home countries.We are encouraged by the findings that no significant differences were found in proportions of foreign-born persons who are in medical care and receiving ART as compared with US-born persons , and that foreign-born persons in medical care are achieving viral suppression in proportions similar to or better than US-born persons. These results suggest that after foreign-born persons navigate channels required to gain access to health care, they do not face significant risk of having worse outcomes than their US-born counterparts.Our study is unique in that the overall sample was larger than most studies of HIV-infected foreign-born persons and had minimal risk of bias due to incomplete or inaccurate reporting . Participants were sampled through healthcare providers and were not excluded from participating in multiple cycles; however, given the low percentages of repeat sampling in the 2010 and 2011 cycle years, we expect minimal bias from inclusion of repeat participants. Results are representative only of foreign-born persons receiving care for HIV. The study was not designed to explore how all foreign-born persons infected with HIV compare with all native-born persons infected with HIV.Weighting was used to adjust for nonresponse, but bias may still have occurred if foreign-born and US-born persons who refused to participate differed on characteristics related to outcomes and covariates included in the analysis. Unique reasons that foreign-born persons might refuse to participate could include language barriers, cultural concerns, or fears of threat to immigration status. MMP avoids asking for information that might reveal undocumented status in an effort to prevent the latter bias. Second, the structure of sampling may have led to decreased probability of selection for patients who are intermittent consumers of healthcare. Some groups likely to be more transitory in care are newly arrived foreign-born and undocumented foreign-born persons. The effect of these potential biases would have been to bias results toward the null hypothesis of no difference between foreign-born and US-born persons, as the foreign-born persons enrolled in the MMP would have been more acculturated and thus similar to US-born persons.In a nationally representative sample of HIV-infected adults receiving medical care in the United States, we found no disparities in ART prescription between foreign-born HIV-infected persons compared with their US-born counterparts, despite the finding that foreign-born persons were more likely to be living at or below the poverty level and uninsured. Additionally, we found that foreign-born persons achieved viral suppression at similar or higher proportions than US-born persons. These findings provide reassurance that current programs (such as the Ryan White HIV/AIDS program) aimed at improving the HIV continuum of care through provision of services to people without adequate healthcare coverage or financial resources have been effective at addressing these needs for foreign-born persons. Finally, 9 in 10 HIV-infected foreign-born persons among this sample of persons receiving HIV medical care were diagnosed with HIV after arrival in the United States, indicating that the risk for HIV acquisition among foreign-born persons immigrating to the United States mainly occurs postmigration. HIV prevention programs should continue to provide services to foreign-born persons to reduce their risk of HIV infection.