Best practices for the visualization, mapping, and manipulation of R-loops.

R-loops represent an abundant class of large non-B DNA structures in genomes. Even though they form transiently and at modest frequencies, interfering with R-loop formation or dissolution has significant impacts on genome stability. Addressing the mechanism(s) of R-loop-mediated genome destabilization requires a precise characterization of their distribution in genomes. A number of independent methods have been developed to visualize and map R-loops, but their results are at times discordant, leading to confusion. Here, we review the main existing methodologies for R-loop mapping and assess their limitations as well as the robustness of existing datasets. We offer a set of best practices to improve the reproducibility of maps, hoping that such guidelines could be useful for authors and referees alike. Finally, we propose a possible resolution for the apparent contradictions in R-loop mapping outcomes between antibody-based and RNase H1-based mapping approaches.

Prevalent, Dynamic, and Conserved R-Loop Structures Associate with Specific Epigenomic Signatures in Mammals.

R-loops are three-stranded nucleic acid structures formed upon annealing of an RNA strand to one strand of duplex DNA. We profiled R-loops using a high-resolution, strand-specific methodology in human and mouse cell types. R-loops are prevalent, collectively occupying up to 5% of mammalian genomes. R-loop formation occurs over conserved genic hotspots such as promoter and terminator regions of poly(A)-dependent genes. In most cases, R-loops occur co-transcriptionally and undergo dynamic turnover. Detailed epigenomic profiling revealed that R-loops associate with specific chromatin signatures. At promoters, R-loops associate with a hyper-accessible state characteristic of unmethylated CpG island promoters. By contrast, terminal R-loops associate with an enhancer- and insulator-like state and define a broad class of transcription terminators. Together, this suggests that the retention of nascent RNA transcripts at their site of expression represents an abundant, dynamic, and programmed component of the mammalian chromatin that affects chromatin patterning and the control of gene expression.

Quality-controlled R-loop meta-analysis reveals the characteristics of R-loop consensus regions.

R-loops are three-stranded nucleic acid structures formed from the hybridization of RNA and DNA. While the pathological consequences of R-loops have been well-studied to date, the locations, classes, and dynamics of physiological R-loops remain poorly understood. R-loop mapping studies provide insight into R-loop dynamics, but their findings are challenging to generalize. This is due to the narrow biological scope of individual studies, the limitations of each mapping modality, and, in some cases, poor data quality. In this study, we reprocessed 810 R-loop mapping datasets from a wide array of biological conditions and mapping modalities. From this data resource, we developed an accurate R-loop data quality control method, and we reveal the extent of poor-quality data within previously published studies. We then identified a set of high-confidence R-loop mapping samples and used them to define consensus R-loop sites called 'R-loop regions' (RL regions). In the process, we identified a stark divergence between RL regions detected by S9.6 and dRNH-based mapping methods, particularly with respect to R-loop size, location, and colocalization with RNA binding factors. Taken together, this work provides a much-needed method to assess R-loop data quality and offers novel context regarding the differences between dRNH- and S9.6-based R-loop mapping approaches.

Neurological Disorders Induced by Drug Use: Effects of Adolescent and Embryonic Drug Exposure on Behavioral Neurodevelopment.

Clinical studies demonstrate that the risk of developing neurological disorders is increased by overconsumption of the commonly used drugs, alcohol, nicotine and cannabis. These drug-induced neurological disorders, which include substance use disorder (SUD) and its co-occurring emotional conditions such as anxiety and depression, are observed not only in adults but also with drug use during adolescence and after prenatal exposure to these drugs, and they are accompanied by long-lasting disturbances in brain development. This report provides overviews of clinical and preclinical studies, which confirm these adverse effects in adolescents and the offspring prenatally exposed to the drugs and include a more in-depth description of specific neuronal systems, their neurocircuitry and molecular mechanisms, affected by drug exposure and of specific techniques used to determine if these effects in the brain are causally related to the behavioral disturbances. With analysis of further studies, this review then addresses four specific questions that are important for fully understanding the impact that drug use in young individuals can have on future pregnancies and their offspring. Evidence demonstrates that the adverse effects on their brain and behavior can occur: (1) at low doses with short periods of drug exposure during pregnancy; (2) after pre-conception drug use by both females and males; (3) in subsequent generations following the initial drug exposure; and (4) in a sex-dependent manner, with drug use producing a greater risk in females than males of developing SUDs with emotional conditions and female offspring after prenatal drug exposure responding more adversely than male offspring. With the recent rise in drug use by adolescents and pregnant women that has occurred in association with the legalization of cannabis and increased availability of vaping tools, these conclusions from the clinical and preclinical literature are particularly alarming and underscore the urgent need to educate young women and men about the possible harmful effects of early drug use and to seek novel therapeutic strategies that might help to limit drug use in young individuals.

An Exploratory Spatiotemporal Analysis of Socio-Environmental Patterns in Severe Maternal Morbidity.

OBJECTIVES: Severe Maternal Morbidity (SMM) is a group of pregnancy complications in which a woman nearly dies. Despite its increasing prevalence, little research has evaluated geographic patterns of SMM and the underlying social determinants that influence excess risk. This study examined the spatial clustering of SMM across South Carolina, US, and its associations with place-based social and environmental factors. METHODS: Hospitalized deliveries from 2012 to 2017 were analyzed using Kulldorff's spatial scan statistic to locate areas with abnormally high rates of SMM. SMM patients inside and outside risk clusters were compared using Generalized Estimating Equations (GEE) to determine underlying individual and community-level risk factors. RESULTS: GEE models revealed that the odds of living in a high-risk SMM21 (SMM including blood transfusions) cluster was 2.49 times higher among Black patients (p < .001) compared to those outside of a high-risk cluster. Women residing in a high-risk SMM20 (SMM excluding blood transfusions) cluster were 1.38 times more likely to experience the most number of extremely hot days and 1.70 times more likely to present with obesity than women in a low-risk SMM cluster (p < .001). CONCLUSIONS: This study is the first to characterize the geographic clustering of SMM risk in the US. Our geospatial approach contributes a novel understanding to factors which influence SMM beyond patient-level characteristics and identifies the impact of hot ambient temperature on maternal morbidity. Findings address an important literature gap surrounding place-based risk factors by explaining the contextual social and built environmental factors that drive SMM risk.

Interplay between DNA sequence and negative superhelicity drives R-loop structures.

R-loops are abundant three-stranded nucleic-acid structures that form in cis during transcription. Experimental evidence suggests that R-loop formation is affected by DNA sequence and topology. However, the exact manner by which these factors interact to determine R-loop susceptibility is unclear. To investigate this, we developed a statistical mechanical equilibrium model of R-loop formation in superhelical DNA. In this model, the energy involved in forming an R-loop includes four terms-junctional and base-pairing energies and energies associated with superhelicity and with the torsional winding of the displaced DNA single strand around the RNA:DNA hybrid. This model shows that the significant energy barrier imposed by the formation of junctions can be overcome in two ways. First, base-pairing energy can favor RNA:DNA over DNA:DNA duplexes in favorable sequences. Second, R-loops, by absorbing negative superhelicity, partially or fully relax the rest of the DNA domain, thereby returning it to a lower energy state. In vitro transcription assays confirmed that R-loops cause plasmid relaxation and that negative superhelicity is required for R-loops to form, even in a favorable region. Single-molecule R-loop footprinting following in vitro transcription showed a strong agreement between theoretical predictions and experimental mapping of stable R-loop positions and further revealed the impact of DNA topology on the R-loop distribution landscape. Our results clarify the interplay between base sequence and DNA superhelicity in controlling R-loop stability. They also reveal R-loops as powerful and reversible topology sinks that cells may use to nonenzymatically relieve superhelical stress during transcription.

The tempo of puberty and its relationship to adolescent health and well-being: A systematic review.

AIM: Emerging evidence suggests that pubertal tempo, that is rate of passage through puberty, has relevance to adolescent mood and behaviour. However, its wider health and developmental significance remain unclear. This systematic review sought to clarify the relationship of pubertal tempo to indicators of health and development, and to document tempo definitions and pubertal durations reported in the literature. METHODS: Eight electronic databases were searched from earliest record to July 2018. Study eligibility: healthy participants; age 8-21 years; ≥2 longitudinal measures of puberty; analysis of tempo against a health or developmental indicator. RESULTS: Thirty-eight studies met eligibility, and these reported on diverse tempo definitions and seven health- and development-related domains. Data sets with varying tempo definitions converged on an association of rapid pubertal progression to: (a) higher adiposity during childhood and adolescence in both sexes; and (b) lower psychosocial well-being in adolescent males. Later thelarche unanimously predicted faster progression to menarche in females, but this compensation was largely undetected when alternate definitions of pubertal timing and/or tempo were used. Duration of puberty ranged from 2.5-4.1 years. CONCLUSION: Pubertal tempo may be clinically relevant when considering trajectories of adiposity and psychosocial well-being among adolescents, especially males. Consensus on the definition of tempo would facilitate between-study comparisons.

An observational study of pregnancy and post-partum outcomes in women with prolactinoma treated with dopamine agonists.

BACKGROUND: In women with prolactinoma medical treatment with dopamine agonists (DA) can restore fertility. A number of studies have established the safety of DA during pregnancy and the impact of pregnancy and lactation on remission of prolactinoma. However, the total number of reported cases remains modest and further evidence is needed. AIMS: To evaluate the safety of DA during pregnancy and remission of prolactinoma after pregnancy and lactation. MATERIALS AND METHODS: Retrospective cohort study (2002-2014) of 57 pregnancies in 47 women with prolactinoma who received DA. Neonatal and pregnancy complications were recorded. Prolactin levels and treatment data were collected at the time of diagnosis, pre-conception, during pregnancy and lactation, and post-partum (up to 114 months). RESULTS: DA treatment was stopped a median of 4.5 weeks after conception in 49 pregnancies (86%). There were 49 live births (86% of pregnancies) and six miscarriages. Six pregnancies had an adverse neonatal outcome including two with congenital malformations. Following 26% of pregnancies women achieved remission after birth or lactation, and 25% of women were in remission at last follow-up. Remission was associated with older maternal age (P = 0.036), a lower prolactin level at diagnosis (P = 0.037), and a smaller adenoma at diagnosis (P = 0.045). CONCLUSIONS: Successful pregnancy and lactation is common after DA treatment for prolactinoma. Fetal exposure in the first four weeks of pregnancy appears to be generally safe. Encouragingly, post-partum and after lactation a quarter of women had a normal prolactin level without medical treatment.

Pain centrality mediates pain self-efficacy and symptom severity among individuals reporting chronic pain.

Chronic pain is consistently associated with the presence of mental health disorders. Although previous research has shown relations between low levels of self-efficacy with chronic pain severity as well as comorbid mental health symptoms, the link between self-efficacy and mental health symptoms in chronic pain is not well understood. This study examined whether pain centrality, the extent to which pain is viewed as central to self-identity, may underlie these associations. Individuals with a diagnosis of chronic pain (N = 89) recruited through MTurkcompleted self-report measures including demographics, self-efficacy, pain centrality, pain severity, depression, and anxiety. Pain severity was associated with higher levels of pain centrality, depression, anxiety, and lower levels of self-efficacy. Path analysis demonstrated pain centrality significantly mediated the relationship between self-efficacy and pain severity, depression, and anxiety. Future studies would benefit from testing whether modifying pain centrality beliefs shift perceptions of control as well as pain and psychological outcomes.

Bilateral Versus Single Internal Mammary Artery Use in Coronary Artery Bypass Grafting: A Propensity Matched Analysis.

BACKGROUND: Bilateral internal mammary artery (BIMA) grafts have demonstrated superior long-term outcomes compared with single internal mammary artery (SIMA) grafts. Despite this, BIMA remains widely underutilised due to perceived technical challenges and concerns regarding wound healing. We sought to examine the morbidity and mortality associated with BIMA use in a propensity-matched cohort of patients. METHODS: From 2009 to 2016, 3,594 consecutive patients underwent coronary artery bypass surgery at three affiliated institutions. Thirty-day (30) mortality and morbidity data were collected prospectively. Propensity-score matched analyses were performed for BIMA versus SIMA use controlling for a number of preoperative characteristics. RESULTS: Overall, 29% of procedures were performed off pump, with a greater proportion in the BIMA group (43% vs. 21%, p<0.001). In the propensity-score analysis consisting of 820 matched pairs, there were similar rates of 30-day mortality (1.3% BIMA vs. 0.9% SIMA, p=0.48) and deep sternal wound infection (1.1% BIMA vs. 0.9% SIMA, p=0.84). The rate of superficial sternal wound infection trended towards being higher in the BIMA group (2.6% vs. 1.3%, p=0.077). The rates of red blood cell transfusions (27.4% vs. 27%, p=0.217), other blood product transfusions (18% vs. 20%, p=0.217), and reoperation for bleeding (2.9% vs. 2.1%, p=0.349) were similar. CONCLUSIONS: Bilateral internal mammary artery use was associated with similar rates of deep sternal wound infection compared to SIMA use, with a preponderance of superficial sternal wound infections that did not result in increased mortality or transfusion requirements. The use of BIMA should be more widely considered for coronary artery bypass surgery.

Comments to Angulo et al. 2016 on "Sea-level fluctuations and coastal evolution in the state of Rio de Janeiro, southeastern - Brazil" by Castro et al. 2014.

Interpretation of sea-level indicators is essential when studying paleo sea-level fluctuations during the Holocene. Sea-level indicators may have different origins, such as geological (beachrocks) and biological (vermetids and barnacles). In order to reconstruct paleo sea-level, it is necessary to attribute an indicative meaning to each sea-level indicator. This paper aims to discuss issues raised by Angulo et al. (2016) regarding to the sea-level fluctuations curve proposed by Castro et al. (2014) to the Rio de Janeiro State coast, Brazilian southeast. The key issue that deserves posing is that local or regional curves cannot be built based on large scale (global) RSL geophysical models even in places of steady crust like Brazil. Here, we put into question the relative sea-level fluctuation curve model proposed by Angulo et al. (2006, 2016) to the coast of Rio de Janeiro State and Pernambuco State. It is strengthened the proposal of using different origins indicators on RSL vertical variation, georeferenced by high precision altitude GPS, adjusted by Brazilian Geodetic System benchmarks, maintained by the Brazilian Institute of Geography and Statistics - IBGE. All issues regarding the curve drawn by Castro et al. (2014) are answered based on field data, laboratory analytical techniques, radiocarbon dating as well as relevant literature.

GC skew is a conserved property of unmethylated CpG island promoters across vertebrates.

GC skew is a measure of the strand asymmetry in the distribution of guanines and cytosines. GC skew favors R-loops, a type of three stranded nucleic acid structures that form upon annealing of an RNA strand to one strand of DNA, creating a persistent RNA:DNA hybrid. Previous studies show that GC skew is prevalent at thousands of human CpG island (CGI) promoters and transcription termination regions, which correspond to hotspots of R-loop formation. Here, we investigated the conservation of GC skew patterns in 60 sequenced chordates genomes. We report that GC skew is a conserved sequence characteristic of the CGI promoter class in vertebrates. Furthermore, we reveal that promoter GC skew peaks at the exon 1/ intron1 junction and that it is highly correlated with gene age and CGI promoter strength. Our data also show that GC skew is predictive of unmethylated CGI promoters in a range of vertebrate species and that it imparts significant DNA hypomethylation for promoters with intermediate CpG densities. Finally, we observed that terminal GC skew is conserved for a subset of vertebrate genes that tend to be located significantly closer to their downstream neighbors, consistent with a role for R-loop formation in transcription termination.

Internal dressings for healing perianal abscess cavities.

BACKGROUND: A perianal abscess is a collection of pus under the skin, around the anus. It usually occurs due to an infection of an anal gland. In the UK, the annual incidence is 40 per 100,000 of the adult population, and the standard treatment is admission to hospital for incision and drainage under general anaesthetic. Following drainage of the pus, an internal dressing (pack) is placed into the cavity to stop bleeding. Common practice is for community nursing teams to change the pack regularly until the cavity heals. Some practitioners in the USA and Australia make a small stab incision under local anaesthetic and place a catheter into the cavity which drains into an external dressing. It is removed when it stops draining. Elsewhere in the USA, simple drainage is performed in an outpatient setting under local anaesthetic. OBJECTIVES: To assess the effects of internal dressings in healing wound cavities resulting from drainage of perianal abscesses. SEARCH METHODS: In May 2016 we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL Plus. We also searched clinical trial registries to identify ongoing and unpublished studies, and searched reference lists of relevant reports to identify additional studies. We did not restrict studies with respect to language, date of publication, or study setting. SELECTION CRITERIA: Published or unpublished randomised controlled trials (RCTs) comparing any type of internal dressing (packing) used in the post-operative management of perianal abscess cavities with alternative treatments or different types of internal dressing. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, risk of bias assessment, and data extraction. MAIN RESULTS: We included two studies, with a total of 64 randomised participants (50 and 14 participants) aged 18 years or over, with a perianal abscess. In both studies, participants were enrolled on the first post-operative day and randomised to continued packing by community district nursing teams or to no packing. Participants in the non-packing group managed their own wounds in the community and used absorbant dressings to cover the area. Fortnightly follow-up was undertaken until the cavity closed and the skin re-epithelialised, which constituted healing. For non-attenders, telephone follow-up was conducted.Both studies were at high risk of bias due to risk of attrition, performance and detection bias.It was not possible to pool the two studies for the outcome of time to healing. It is unclear whether continued post-operative packing of the cavity of perianal abscesses affects time to complete healing. One study reported a mean time to wound healing of 26.8 days (95% confidence interval (CI) 22.7 to 30.7) in the packing group and 19.5 days (95% CI 13.6 to 25.4) in the non-packing group (it was not clear if all participants healed). We re-analysed the data and found no clear difference in the time to healing (7.30 days longer in the packing group, 95% CI -2.24 to 16.84; 14 participants). This was assessed as very low quality evidence (downgraded three levels for very serious imprecision and serious risk of bias). The second study reported a median time to complete wound healing of 24.5 days (range 10 to 150 days) in the packing group and 21 days (range 8 to 90 days) in the non-packed group. There was insufficient information to be able to recreate the analysis and the original analysis was inappropriate (did not account for censoring). This second study also provided very low quality evidence (downgraded four levels for serious risk of bias, serious indirectness and very serious imprecision).There was very low quality evidence (downgraded for risk of bias, indirectness and imprecision) of no difference in wound pain scores at the initial dressing change. Both studies also reported patients' retrospective judgement of wound pain over the preceding two weeks (visual analogue scale, VAS) as lower for the non-packed group (2; both studies) compared with the packed group (0; both studies); (very low quality evidence) but we have been unable to reproduce these analyses as no variance data were published.There was no clear evidence of a difference in the number of post-operative fistulae detected between the packed and non-packed groups (risk ratio (RR) 2.31, 95% CIs 0.56 to 9.45, I(2) = 0%) (very low quality evidence downgraded three levels for very serious imprecision and serious risk of bias).There was no clear evidence of a difference in the number of abscess recurrences between the packed and non-packed groups over the variable follow-up periods (RR 0.72, 95% CI 0.22 to 2.37, I(2) = 0%) (very low quality evidence downgraded three levels for serious risk of bias and very serious imprecision).No study reported participant health-related quality of life/health status, incontinence rates, time to return to work or normal function, resource use in terms of number of dressing changes or visits to a nurse, or change in wound size. AUTHORS' CONCLUSIONS: It is unclear whether using internal dressings (packing) for the healing of perianal abscess cavities influences time to healing, wound pain, development of fistulae, abscess recurrence or other outcomes. Despite this absence of evidence, the practice of packing abscess cavities is commonplace. Given the lack of high quality evidence, decisions to pack may be based on local practices or patient preferences. Further clinical research is needed to assess the effects and patient experience of packing.

The variable nature of convection in the tropics and subtropics: A legacy of 16 years of the Tropical Rainfall Measuring Mission satellite.

For over 16 years, the Precipitation Radar of the Tropical Rainfall Measuring Mission (TRMM) satellite detected the three-dimensional structure of significantly precipitating clouds in the tropics and subtropics. This paper reviews and synthesizes studies using the TRMM radar data to present a global picture of the variation of convection throughout low latitudes. The multiyear data set shows convection varying not only in amount but also in its very nature across the oceans, continents, islands, and mountain ranges of the tropics and subtropics. Shallow isolated raining clouds are overwhelmingly an oceanic phenomenon. Extremely deep and intense convective elements occur almost exclusively over land. Upscale growth of convection into mesoscale systems takes a variety of forms. Oceanic cloud systems generally have less intense embedded convection but can form very wide stratiform regions. Continental mesoscale systems often have more intense embedded convection. Some of the most intense convective cells and mesoscale systems occur near the great mountain ranges of low latitudes. The Maritime Continent and Amazonia exhibit convective clouds with maritime characteristics although they are partially or wholly land. Convective systems containing broad stratiform areas manifest most strongly over oceans. The stratiform precipitation occurs in various forms. Often it occurs as quasi-uniform precipitation with strong melting layers connected with intense convection. In monsoons and the Intertropical Convergence Zone, it takes the form of closely packed weak convective elements. Where fronts extend into the subtropics, broad stratiform regions are larger and have lower and sloping melting layers related to the baroclinic origin of the precipitation.

Socioeconomic inequality and mortality--a regional Danish cohort study.

BACKGROUND: Socioeconomic inequalities in mortality pose a serious impediment to enhance public health even in highly developed welfare states. This study aimed to improve the understanding of socioeconomic disparities in all-cause mortality by using a comprehensive approach including a range of behavioural, psychological, material and social determinants in the analysis. METHODS: Data from The North Denmark Region Health Survey 2007 among residents in Northern Jutland, Denmark, were linked with data from nationwide administrative registries to obtain information on death in a 5.8-year follow-up period (1(st) February 2007- 31(st) December 2012). Socioeconomic position was assessed using educational status as a proxy. The study population was assigned to one of five groups according to highest achieved educational level. The sample size was 8,837 after participants with missing values or aged below 30 years were excluded. Cox regression models were used to assess the risk of death from all causes according to educational level, with a step-wise inclusion of explanatory covariates. RESULTS: Participants' mean age at baseline was 54.1 years (SD 12.6); 3,999 were men (45.3%). In the follow-up period, 395 died (4.5%). With adjustment for age and gender, the risk of all-cause mortality was significantly higher in the two least-educated levels (HR = 1.5, 95%, CI = 1.2-1.8 and HR = 3.7, 95% CI = 2.4-5.9, respectively) compared to the middle educational level. After adjustment for the effect of subjective and objective health, similar results were obtained (HR = 1.4, 95% CI = 1.1-1.7 and HR = 3.5, 95% CI = 2.0-6.3, respectively). Further adjustment for the effect of behavioural, psychological, material and social determinants also failed to eliminate inequalities found among groups, the risk remaining significantly higher for the least educated levels (HR = 1.4, 95% CI = 1.1-1.9 and HR = 4.0, 95% CI = 2.3-6.8, respectively). In comparison with the middle level, the two highest educated levels remained statistically insignificant throughout the entire analysis. CONCLUSION: Socioeconomic inequality influenced mortality substantially even when adjusted for a range of determinants that might explain the association. Further studies are needed to understand this important relationship.

How do experts define relevance criteria when initiating Health Impact Assessments of national policies?

AIM: The aim of this article is to present how the Danish Disease Prevention Committee (DDPC) members and HIA-experts understand when HIA is "relevant", which in this context means when there is "presumed to be a direct and documented effect on the health and morbidity of citizens". METHOD: DDPC members were interviewed face-to-face; HIA experts participated in an e-survey. RESULTS: Six DDPC members were interviewed and 100 HIA-experts participated in a survey. The DDPC members consider direct as the link between determinants and the related risk factors. The HIA experts consider direct as the link between policy and the related risk factors. Both groups favour the use of scientific evidence according to the traditional biomedical evidence hierarchy but HIA-experts also judge that there is value in using evidence that can be considered weak such as local community knowledge. CONCLUSIONS: It is clear that the DDPC recommendation gives rise to a discussion on differing perceptions of relevance. The same definition can be used for both direct and indirect effects depending on interpretation. Documented evidence for an effect is desirable in the form provided by the traditional biomedical evidence hierarchy but HIA-experts emphasises use of local knowledge. The primary criteria for initiating a HIA, is whether the outcome of the HIA is expected to be taken into account in the decision-making process. The second criteria, is how do decision-makers perceive or interpret a decision to be relevant for HIA. This has implications for how and whether HIA will be implemented in Denmark in the future.

Individual social capital and survival: a population study with 5-year follow-up.

BACKGROUND: The concept of social capital has received increasing attention as a determinant of population survival, but its significance is uncertain. We examined the importance of social capital on survival in a population study while focusing on gender differences. METHODS: We used data from a Danish regional health survey with a five-year follow-up period, 2007-2012 (n = 9288, 53.5% men, 46.5% women). We investigated the association between social capital and all-cause mortality, performing separate analyses on a composite measure as well as four specific dimensions of social capital while controlling for covariates. Analyses were performed with Cox proportional hazard models by which hazard ratios and 95% confidence intervals were calculated. RESULTS: For women, higher levels of social capital were associated with lower all-cause mortality regardless of age, socioeconomic status, health, and health behaviour (HR = 0.586, 95% CI = 0.421-0.816) while no such association was found for men (HR = 0.949, 95% CI = 0.816-1.104). Analysing the specific dimensions of social capital, higher levels of trust and social network were significantly associated with lower all-cause mortality in women (HR = 0.827, 95% CI = 0.750-0.913 and HR = 0.832, 95% CI = 0.729-0.949, respectively). For men, strong social networks were associated with a higher risk of all-cause mortality (HR = 1.132, 95% CI = 1.017-1.260). Civic engagement had a similar effect for both men (HR = 0.848, 95% CI = 0.722-0.997) and women (HR = 0.848, 95% CI = 0.630-1.140). CONCLUSIONS: We found differential effects of social capital in men compared to women. The predictive effects on all-cause mortality of four specific dimensions of social capital varied. Gender stratified analysis and the use of multiple indicators to measure social capital are thus warranted in future research.

What have adolescents in Rio de Janeiro city, Brazil, done to reduce their community violence exposure? / O que os adolescentes do município do Rio de Janeiro, Brasil, têm feito para reduzir sua exposição à violência comunitária?

This study aims to identify the individual community strategies to avoid violence exposure most used by adolescents from public and private schools in the IX Administrative Region of Rio de Janeiro and investigate the profile of co-occurrence and its prevalence in specific population subgroups. This is a cross-sectional study with 693 individuals. A multidimensional questionnaire collected information regarding strategies to avoid community violence exposure and was self-completed in the classroom. The most used strategies were avoiding walking close to armed people (55.5%), avoiding walking alone (30.5%), and avoiding returning home at dawn (24.7%). Girls adopt more of all (concurrently) the four limiting behaviors to reduce their community violence exposure (53% vs. 32%). Notably, the adoption of such strategies differed by socioeconomic indicators and was higher among adolescents from lower-income households. These findings point to the high frequency of use of such strategies by adolescents, which may hinder and limit the full development of their social and cultural skills.

O objetivo do estudo é conhecer as estratégias individuais mais utilizadas por adolescentes de escolas públicas e privadas da IX Região Administrativa do município do Rio de Janeiro para evitar a exposição à violência comunitária, bem como investigar o perfil de coocorrência e sua prevalência em subgrupos populacionais específicos. Trata-se de um estudo seccional com 693 indivíduos. As informações referentes às estratégias para evitar a exposição à violência comunitária foram coletadas por meio de questionário multidimensional autopreenchido em sala de aula. As estratégias mais utilizadas foram: evitar passar onde há pessoas armadas (55,5%), evitar andar sozinho (30,5%) e evitar voltar para casa de madrugada (24,7%). Observou-se que as meninas adotam mais todos (concomitantemente) os quatro tipos de comportamento limitantes para reduzir sua exposição à violência comunitária (53% vs. 32%). Ressalta-se que a adoção de tais estratégias diferiu segundo os indicadores socioeconômicos, sendo maior entre os adolescentes oriundos de família de estratos de renda mais baixos. Tais achados chamam a atenção para a alta frequência de utilização de tais estratégias por adolescentes, o que pode cercear e limitar o pleno desenvolvimento de suas habilidades sociais e culturais.