Do shared etiological factors contribute to the relationship between sexual orientation and depression?

Genetic and Environmental Influences on Sexual Orientation: Moderation by Childhood Gender Nonconformity and Early-Life Adversity

Existing evidence indicates genetic and non-genetic influences on sexual orientation; however, the possibility of gene-environment interplay has not been previously formally tested despite theories indicating this. Using a Finnish twin cohort, this study investigated whether childhood gender nonconformity and early-life adversities independently moderated individual differences in sexual orientation and childhood gender nonconformity, the relationship between them, and the etiological bases of the proposed moderation effects. Sexual orientation, childhood gender nonconformity, and early-life adversities were assessed using standard questionnaires. Structural equation twin model fitting was carried out using OpenMx. Childhood gender nonconformity was significantly associated with reduced phenotypic variance in sexual orientation (β =  - 0.14, 95% CI - 0.27, - 0.01). A breakdown of the underlying influences of this moderation effect showed that this was mostly due to moderation of individual-specific environmental influences which significantly decreased as childhood gender nonconformity increased (βE =  - 0.38; 95% CI - 0.52, - 0.001) while additive genetic influences were not significantly moderated (βA = 0.05; 95% CI - 0.30, 0.27). We also observed that the relationship between sexual orientation and childhood gender nonconformity was stronger at higher levels of childhood gender nonconformity (β = 0.10, 95% CI 0.05, 0.14); however, significance of the underlying genetic and environmental influences on this relationship could not be established in this sample. The findings indicate that beyond a correlation of their genetic and individual-specific environmental influences, childhood gender nonconformity is further significantly associated with reduced individual-specific influences on sexual orientation.

Adverse Childhood Experiences and Sexual Orientation: An Intersectional Analysis of Nationally Representative Data

INTRODUCTION

This study compared the prevalence of adverse childhood experiences across intersections of sexual orientation, gender, race/ethnicity, and economic status.

METHODS

Data collected between 1994 and 2018 from 12,519 participants in the National Longitudinal Study of Adolescent to Adult Health were analyzed in 2023 to generate adverse childhood experience prevalence estimates. Unadjusted 1-way ANOVAs and multivariate regressions were performed to compare differences in independent and cumulative adversity measures by sexual orientation, gender, race/ethnicity, and poverty status. A multilevel analysis of individual heterogeneity and discriminatory accuracy was conducted to estimate adversity scores across 24 groups that were stratified by sexual orientation, gender, race/ethnicity, and poverty status.

RESULTS

Adolescents with same-sex attractions and adults who identified with a sexual minority group reported more adverse childhood experiences overall than straight participants, although associations varied by type of adversity. Strikingly, adversity scores were higher among White youth with same-sex attractions than among Black youth with same-sex attractions, among more economically advantaged bisexual adults than among poorer ones, and among poor White participants than among poor Black and Hispanic participants, suggesting that the combination of disadvantaged and marginalized statuses does not necessarily correspond with greater childhood adversity. A multilevel analysis of individual heterogeneity and discriminatory accuracy interaction model showed that sexual orientation and poverty status contributed significant variance to cumulative adversity scores, whereas gender and race/ethnicity did not.

CONCLUSIONS

The results show that disparities in adverse experiences can be more fully and accurately represented when sexual orientation and other social identities are modeled as intersectional configurations. Given that adverse childhood experiences are linked to morbidity and mortality, the findings have salient implications for understanding health disparities that affect population subgroups.

Health Outcomes of Sexual Minority Women Who Have Experienced Adverse Childhood Experiences: A Scoping Review

Sexual minority women (SMW; e.g., lesbian, bisexual) report higher rates of almost every negative physical health (e.g., asthma, arthritis, cardiovascular disease), mental health (e.g., depression, anxiety), and substance use outcome compared to heterosexual women. Adverse Childhood Experiences (ACEs) have been identified as risk factors for negative health outcomes. Despite this, no study to date has synthesized existing literature examining ACEs and health outcomes among SMW. This gap is important because SMW are significantly more likely than heterosexual women to report every type of ACE and a higher total number of ACEs. Therefore, using a scoping review methodology, we sought to expand understanding of the relationship between ACEs and health outcomes among SMW. Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for. Scoping Reviews protocol, we searched five databases: Web of Science, PsycInfo, CINAHL, PubMed, and Embase for studies published between January 2000 and June 2021 that examined mental health, physical health, and/or substance use risk factors and outcomes among adult cisgender SMW who report ACEs. Our search yielded 840 unique results. Studies were screened independently by two authors to determine eligibility, and 42 met full inclusion criteria. Our findings provide strong evidence that ACEs are an important risk factor for multiple negative mental health and substance use outcomes among SMW. However, findings were mixed with respect to some health risk behaviors and physical health outcomes among SMW, highlighting the need for future research to clarify these relationships.

The fraternal birth-order effect as a statistical artefact: convergent evidence from probability calculus, simulated data, and multiverse meta-analysis

The fraternal-birth order effect (FBOE) is a research claim which states that each older brother increases the odds of homosexual orientation in men via an immunoreactivity process known as the maternal immune hypothesis. Importantly, older sisters supposedly either do not affect these odds, or affect them to a lesser extent. Consequently, the fraternal birth-order effect predicts that the association between the number of older brothers and homosexual orientation in men is greater in magnitude than any association between the number of older sisters and homosexual orientation. This difference in magnitude represents the main theoretical estimand of the FBOE. In addition, no comparable effects should be observable among homosexual vs heterosexual women. Here, we triangulate the empirical foundations of the FBOE from three distinct, informative perspectives, complementing each other: first, drawing on basic probability calculus, we deduce mathematically that the body of statistical evidence used to make inferences about the main theoretical estimand of the FBOE rests on incorrect statistical reasoning. In particular, we show that throughout the literature researchers ascribe to the false assumptions that effects of family size should be adjusted for and that this could be achieved through the use of ratio variables. Second, using a data-simulation approach, we demonstrate that by using currently recommended statistical practices, researchers are bound to frequently draw incorrect conclusions. And third, we re-examine the empirical evidence of the fraternal birth-order effect in men and women by using a novel specification-curve and multiverse approach to meta-analysis (64 male and 17 female samples, N = 2,778,998). When analyzed correctly, the specific association between the number of older brothers and homosexual orientation is small, heterogenous in magnitude, and apparently not specific to men. In addition, existing research evidence seems to be exaggerated by small-study effects.

Suicidality and protective factors among sexual and gender minority youth and adults in Canada: a cross-sectional, population-based study

BACKGROUND

Sexual and gender minority populations experience elevated risks for suicidality. This study aimed to assess prevalence and disparities in non-fatal suicidality and potential protective factors related to social support and health care access among sexual and gender minority youth and adults and their heterosexual and cisgender counterparts in Canada. The second objective was to examine changes in the prevalence of suicidal ideation and protective factors during the COVID-19 pandemic.

METHODS

Pooled data from the 2015, 2016 and 2019 Canadian Community Health Surveys were used to estimate pre-pandemic prevalence of suicidal ideation, plans and attempts, and protective factors. The study also estimated changes in the prevalence of recent suicidal ideation and protective factors in fall 2020, compared with the same period pre-pandemic.

RESULTS

The prevalence of suicidality was higher among the sexual minority populations compared with the heterosexual population, and the prevalence was highest among the bisexual population, regardless of sex or age group. The pre-pandemic prevalence of recent suicidal ideation was 14.0% for the bisexual population, 5.2% for the gay/lesbian population, and 2.4% for the heterosexual population. The prevalence of lifetime suicide attempts was 16.6%, 8.6%, and 2.8% respectively. More than 40% of sexual minority populations aged 15-44 years had lifetime suicidal ideation; 64.3% and 36.5% of the gender minority population had lifetime suicidal ideation and suicide attempts. Sexual and gender minority populations had a lower prevalence of protective factors related to social support and health care access. The prevalence of recent suicidal ideation among sexual and gender minority populations increased in fall 2020, and they tended to experience longer wait times for immediate care needed.

CONCLUSIONS

Sexual and gender minority populations had a higher prevalence of suicidality and less social support and health care access compared to the heterosexual and cisgender populations. The pandemic was associated with increased suicidal ideation and limited access to care for these groups. Public health interventions that target modifiable protective factors may help decrease suicidality and reduce health disparities.

Minority stress theory: Application, critique, and continued relevance

The minority stress model has been influential in guiding research on sexual and gender minority health and well-being in psychology and related social and health sciences. Minority stress has theoretical roots in psychology, sociology, public health, and social welfare. Meyer provided the first integrative articulation of minority stress in 2003 as an explanatory theory aimed at understanding the social, psychological, and structural factors accounting for mental health inequalities facing sexual minority populations. This article reviews developments in minority stress theory over the past two decades, focusing on critiques, applications, and reflections on its continued relevance in the context of rapidly changing social and policy contexts.

Mental health and substance use among sexual minority women who report childhood sexual abuse: A systematic literature review

OBJECTIVE

A growing body of literature provides evidence that sexual minority women (SMW; e.g., lesbian, bisexual) are at greater risk of negative mental health and substance use outcomes than are heterosexual women. While minority stress may partially explain these disparities, it does not fully account for them. Therefore, it is necessary to identify how other risk factors (i.e., childhood sexual abuse [CSA]) contribute to SMW's increased risk of negative mental health and substance use outcomes.

METHOD

We conducted a systematic literature review to identify and synthesize the state of knowledge about CSA and mental health and substance use outcomes among SMW. Two independent reviewers screened 347 articles identified in searches of five databases (Web of Science, PsycInfo, CINAHL, PubMed, and Embase). Eligible articles were peer-reviewed, reported quantitative or mixed methods results focused on mental health or substance use outcomes among adult SMW with a history of CSA.

RESULTS

Twenty-four papers were included in the review. Findings clearly show that SMW report higher rates of CSA than heterosexual women. Findings also suggest that CSA may mediate the relationship between minority sexual identity and some negative outcomes.

CONCLUSIONS

Future studies should include minority stress factors, a broader range of mental health outcomes (apart from substance use and suicide), and more nuanced measures of CSA. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Elevated Psychiatric Risk in Same-Sex Married Individuals: Large-scale Evidence is Consistent with a Substantial Role of Familial Common Causes

Xu et al. present a study of practically the whole Swedish-born population over the age of 25, in which they report an elevated risk in same-sex (compared to opposite-sex) married individuals of depression, substance abuse, and attempted or completed suicide. This elevated psychiatric risk is substantially reduced when same-sex married individuals are compared with their opposite-sex married siblings, which is consistent with a substantial role of familial (e.g., genetic and shared environmental) common causes of both same-sex orientation and psychiatric risk. I discuss the study's strengths, including its huge, comprehensive sample and its use of objective measures, which avoid some of the potential biases in other studies. I also discuss the study's limitations and argue that the authors misinterpret the role of shared familial influences as accounting for a "small proportion (less than 20%)" of the elevated psychiatric risk in same-sex married individuals. The proportion shown by their results is much larger than the authors report, and even these larger values are best understood as lower bounds in terms of what could be accounted for by familial common causes. Lastly, I discuss future directions for research aiming to understand elevated psychiatric risk in lesbian, gay, and bisexual individuals.

Same-Sex Marriage and Common Mental Health Diagnoses: A Sibling Comparison and Adoption Approach

We aimed to test whether the association between same-sex marriage and common mental health diagnoses was explained by shared genetic and environmental familial influences using sibling comparison and adoption analyses. For the sibling comparison analysis, participants (1,177,712 men and 1,266,917 women) were individuals born in Sweden between 1932 and 1994 and had ever been recorded as married (in opposite-sex or same-sex marriages). For the adoption analysis, participants were 147,164 and 1,298 female-female full sibling and adoptive sibling pairs, respectively. Based on medical records, prescribed medication, and death certificates, depression, substance abuse, and suicide (completed and attempted) from age 18 years were identified. For both sexes, being in a same-sex marriage was associated with greater risk of depression, substance abuse, and suicide, compared with being in an opposite-sex marriage. Controlling for shared familial confounding reduced this difference by less than 20% in magnitude, but overall mental health disparities for individuals in same-sex marriages remained statistically significant. Among women, only the genetic correlation between same-sex marriage and depression was statistically significant (r = .33). Same-sex marriage, as a proxy for sexual orientation, was associated with increased risk of certain mental health diagnoses and shared familial confounding explained a small component of this association, depending on the diagnosis. The findings indicate that sexual orientation disparities in mental health outcomes may involve unmeasured factors, and a relatively small proportion should be considered that may be due to shared familial confounding relevant to both sexual orientation and psychopathology.

Health Disparities by Sexual Orientation: Implications of Genetic and Environmental Explanations

Xu and colleagues add to the growing research literature on the role of potential familial (i.e., genetic and shared environment) causes in sexual orientation and in the relation between sexual orientation and poor mental health, in which lesbian, gay, bisexual, and other sexual minority individuals have poorer mental health than heterosexual individuals. I address several implications of the findings by Xu et al. and others. First, the nuance or complexity of genetics is considered, given the implications of genetics for health via a single gene, epistasis, or epigenetics. Second, I highlight the magnitude of the genetic relation between sexual orientation and psychopathology, suggesting some, but not all, sexual minority individuals may differ from heterosexual individuals on psychiatric vulnerability. In turn, this suggests that research should identify for whom or under what circumstances the relation holds. Third, I underscore the need for a within-subjects design, in which attention turns to differences among sexual minority individuals. Fourth, the need to reevaluate Minority Stress Theory, the predominant theory accounting for health disparities by sexual orientation, is addressed because of the implications of genetics for health. Fifth, I acknowledge the concern attached to genetic research for potentially compounding the stigmatization already experienced by sexual minority individuals. Nevertheless, this research is occurring and will likely increase in volume. It will inform understanding of sexual minority individuals.

Causal Influences of Same-Sex Attraction on Psychological Distress and Risky Sexual Behaviors: Evidence for Bidirectional Effects

Although health disparities among same-sex attracted compared to heterosexual individuals are typically explained by minority stress, there is limited evidence for a causal effect. This study investigated whether same-sex attraction was causally associated with psychological distress and risky sexual behavior using sociosexual behavior as a proxy. The sample comprised monozygotic and dizygotic twins and their non-twin siblings (n = 2036, 3780 and 2356, respectively) genotyped and assessed for same-sex attraction, psychological distress (anxiety and depressive symptoms), and risky sexual behavior. Causal influences were investigated with same-sex attraction as the predictor and psychological distress and risky sexual behavior as the outcomes in two separate Mendelian Randomization-Direction of Causation (MRDoC) models using OpenMx in R. The MRDoC model improves on the Mendelian Randomization and Direction of Causation twin models by allowing analyses of variables with similar genetic architectures, incorporating polygenic scores as instrumental variables and specifying pleiotropy and residual covariance. There were significant causal influences flowing from same-sex attraction to psychological distress and risky sexual behavior (standardized coefficients = 0.13 and 0.16; 95% CIs 0.03-0.23 and 0.08-0.25, respectively). Further analyses also demonstrated causal influences flowing from psychological distress and risky sexual behavior toward same-sex attraction. Causal influences from same-sex attraction to psychological distress and risky sexual behavior may reflect minority stress, which reinforces ongoing measures to minimize social disparities. Causal influences flowing in the opposite direction may reflect rejection sensitivity, stigma-inducing outcomes of risky sexual behavior, and recall bias; however, further research is required to specifically investigate these processes.

Sexual-orientation differences in risk of health-related impaired ability to work and to remain in the paid workforce: a prospective population-based twin study

BACKGROUND

Studies consistently show an increased risk of poor health among sexual minorities (i.e., those identifying as lesbian, gay, bisexual [LGB] or other non-heterosexuals individuals), as compared to those identifying as heterosexual. It is largely unknown whether the increased risk of mental and physical health problems among sexual minorities is also reflected in an increased risk of health-related impaired ability to work, in terms of sickness absence (SA) and disability pension (DP), or successfully remain in the paid workforce. This study made use of a large sample of Swedish twins with self-reported information about sexual behavior in young adulthood to examine sexual orientation difference in SA and DP during a 12-year follow-up period.

METHOD

Data from the Swedish Twin project of Disability pension and Sickness absence (STODS), including Swedish twins born 1959-1985 was used (N = 17,539; n = 1,238 sexual minority). Self-report survey data on sexual behavior was linked to information about SA and DP benefits from the MicroData for Analysis of the Social Insurance database (MiDAS), the National Social Insurance Agency. Sexual orientation differences in SA and DP between 2006 and 2018 was analyzed, as well as, the influence of sociodemographic, social stress exposure (i.e., victimization, discrimination), mental health treatment, and family confounding on these differences.

RESULTS

Compared to heterosexuals, sexual minorities were more likely to having experienced SA and having been granted DP. The odds were highest for DP, where sexual minorities were 58% more likely to having been granted DP compared to heterosexuals. The higher odds for SA due to any diagnosis could largely be explained by sociodemographic factors. The higher odds of SA due to mental diagnosis could partially be explained by increased risk of being exposed to discrimination and victimization, and partially by having received treatment with antidepressant medication. The higher odds of being granted DP could also partially be explain by increased risk of being exposed to social stress and treatment with antidepressant medication.

CONCLUSION

To our knowledge, this is the first study to report on sexual orientation differences in risk of SA and DP in a population-based sample. We found higher period prevalence of both SA and DP among sexual minorities as compared to heterosexuals. The higher odds of SA and DP could partially or fully be explained by sexual orientation differences in sociodemographic factors, exposure to social stress, and antidepressant treatment for depression. Future studies can extend these findings by continuing to investigate risk factors for SA and DP among sexual minorities and how such factors can be reduced.

Bidirectional Causal Associations Between Same-Sex Attraction and Psychological Distress: Testing Moderation and Mediation Effects

Only one study has examined bidirectional causality between sexual minority status (having same-sex attraction) and psychological distress. We combined twin and genomic data from 8700 to 9700 participants in the UK Twins Early Development Study cohort at ≈21 years to replicate and extend these bidirectional causal effects using separate unidirectional Mendelian Randomization-Direction of Causation models. We further modified these models to separately investigate sex differences, moderation by childhood factors (retrospectively-assessed early-life adversity and prospectively-assessed childhood gender nonconformity), and mediation by victimization. All analyses were carried out in OpenMx in R. Same-sex attraction causally influenced psychological distress with significant reverse causation (beta = 0.19 and 0.17; 95% CIs = 0.09, 0.29 and 0.08, 0.25 respectively) and no significant sex differences. The same-sex attraction → psychological distress causal path was partly mediated by victimization (12.5%) while the reverse causal path was attenuated by higher childhood gender nonconformity (moderation coefficient = -0.09, 95% CI: -0.13, -0.04).

Adverse Childhood Experiences and Adult Tobacco Use Among Sexual and Gender Minority Populations: Examining the Role of Mental, Social, and Community Health

Purpose: We sought to evaluate the relationship between adverse childhood experiences (ACEs) and tobacco use, to assess the intersection of sexual orientation or gender identity (SOGI), and to explore risk and protective aspects of mental, social, and community health. Methods: This was a secondary analysis of the sexual and gender minorities (SGM) subsample (n = 1102) from a 2019 Community Health Needs Assessment. Nested binary logistic regression models were created to evaluate associations between ACEs and type of tobacco use: (1) cigarette use versus no cigarette or electronic nicotine delivery systems (ENDS) use, (2) ENDS use versus no cigarette or ENDS use, and (3) dual use versus use of either cigarettes or ENDS. Results: The sample population that reported four or more ACEs and ENDS use had statistically significant adjusted odds ratios (aORs) when adjusting the models for sociodemographic variables (aOR = 2.55; 95% confidence intervals [CIs]: 1.54-4.22), SOGI (aOR = 2.44; 95% CI: 1.46-4.10), current mental health (aOR = 2.23; 95% CI: 1.32-3.75), and social and community health (aOR = 2.19; 95% CI: 1.30-3.71). The sample population that reported poor mental health had statistically significant aORs when adjusting the models for sociodemographic variables, SOGI, and mental health (aOR = 2.26; 95% CI: 1.32-3.89) and social and community health (aOR = 2.06; 95% CI: 1.17-3.54). There was no statistically significant finding related to the other tobacco use variables (tobacco use and dual use). Conclusion: We found that high-risk ACEs were positively associated with cigarette use and ENDS use. SGM populations have differing experiences when considering community and social support.

Sexual orientation disparities in the developmental trajectories of emotional and behavioral difficulties from childhood to early adolescence

BACKGROUND

Lesbian, gay, bisexual, and asexual adolescents are at increased risk of poor mental health outcomes but it remains unknown whether this disparity emerges from early childhood and through to adolescence. This study tested sexual orientation disparities in the developmental trajectories of emotional and behavioral difficulties from ages 5 to 14 years, and the influence of early life adversities upon them.

METHODS

The Millennium Cohort Study, a British birth cohort, was used (4,838 boys and 5,016 girls). Parent-report emotional and behavioral difficulties at ages 5, 7, 11, and 14 were measured using the Strength and Difficulties Questionnaire. Sexual orientation was measured via sexual attraction at age 17. Early life adversities in the first 5 years of life, including parental age at birth, birthweight, duration of breastfeeding, parent-child relationship quality, and parental absence, were collected prospectively.

RESULTS

Latent growth modeling suggested that, for both sexes, sexual orientation disparities in emotional and behavioral difficulties increased from age 5 to 14 years. Homosexual and bisexual girls displayed significantly greater emotional and behavioral difficulties than heterosexual girls at ages 7, 11, and 14. Homosexual and bisexual boys displayed significantly greater emotional and behavioral difficulties than heterosexual boys at ages 11 and 14. Asexual boys and girls displayed significantly greater emotional and behavioral difficulties than their heterosexual counterparts at all four ages. For both sexes, sexual orientation disparities in emotional and behavioral difficulties only reduced slightly in magnitude after controlling for early life adversities.

CONCLUSIONS

Sexual minority disparities in emotional and behavioral difficulties increased from childhood to early adolescence, possibly due to the accumulation of susceptibility to minority-related stressors. Sex and early life adversity may contribute to these developmental disparities.

Neuroticism and Sexual Orientation-Based Victimization as Mediators of Sexual Orientation Disparities in Mental Health

This study tested whether elevated risk of poorer mental health outcomes among nonheterosexual adolescents compared with heterosexual adolescents is plausibly explained by neuroticism and sexual orientation-based victimization. The Millennium Cohort Study, a large British prospective birth cohort, was used (4566 heterosexual boys, 77 bisexual boys, 129 homosexual boys, 96 asexual boys, 4444 heterosexual girls, 280 bisexual girls, 158 homosexual girls, and 182 asexual girls). We analyzed the following measures assessed at age 17 years: sexual orientation based on sexual attraction, neuroticism, sexual orientation-based victimization, self-harm attempts, and psychological well-being. Mediation analysis was undertaken separately by sex and yielded the following statistically significant findings: for both sexes, we found that bisexual and homosexual adolescents scored higher than heterosexual adolescents on neuroticism; for both sexes, bisexual and homosexual adolescents reported more negative psychological well-being scores and self-harm attempts compared with heterosexual adolescents, with total effects (standardized regression coefficients) ranging from .58 to .91; those associations were mediated through sexual orientation-based victimization and neuroticism scores, with the indirect effects (standardized regression coefficients) through sexual orientation-based victimization and neuroticism scores ranging from .09 to .26 and .16 to .55, respectively. Asexual adolescents did not differ significantly from their heterosexual counterparts in psychological well-being and self-harm attempts, with the total effects ranging from - .02 to .21. Sexual orientation-based victimization and neuroticism may both contribute to the sexual orientation-related disparities in psychological well-being and self-harm attempts. However, neuroticism appears to the more powerful factor.

New Data on Birth Order in Homosexual Men and Women and a Reply to Vilsmeier et al. (2021a, 2021b)

The fraternal birth order effect (FBOE) is the repeated finding that older brothers increase the odds of homosexuality in later-born males. It has been our working assumption, based on the majority of previous studies, that a similar FBOE does not occur in females. In an elaborate quantitative review posted last year to a preprint server, Vilsmeier et al. (2021a) concluded that there is no valid evidence for an FBOE in men or women. Ablaza et al. (2022) subsequently published a study of population-level data from the Netherlands with conclusions completely opposite to those of Vilsmeier et al., namely, that there is robust evidence of an FBOE in both men and women. The present research was initially undertaken to refute the assertion of Vilsmeier et al. that there is no proof of an FBOE in men and to investigate how they obtained such a discrepant conclusion. We found evidence that the discrepancy may relate to Vilsmeier et al.'s use of the large and demonstrably unreliable sample published by Frisch and Hviid (2006). After the publication by Ablaza et al., we expanded our article to address their finding of an FBOE in women. We argue that our preferred explanation of the FBOE in men-that it reflects the progressive immunization of some mothers to Y-linked antigen by each succeeding male fetus and the concomitantly increasing effects of anti-male antibody on sexual differentiation in the brain in each succeeding male fetus-could plausibly be extended to female homosexuality.

Rethinking minority stress: A social safety perspective on the health effects of stigma in sexually-diverse and gender-diverse populations

For over two decades, the minority stress model has guided research on the health of sexually-diverse individuals (those who are not exclusively heterosexual) and gender-diverse individuals (those whose gender identity/expression differs from their birth-assigned sex/gender). According to this model, the cumulative stress caused by stigma and social marginalization fosters stress-related health problems. Yet studies linking minority stress to physical health outcomes have yielded mixed results, suggesting that something is missing from our understanding of stigma and health. Social safety may be the missing piece. Social safety refers to reliable social connection, inclusion, and protection, which are core human needs that are imperiled by stigma. The absence of social safety is just as health-consequential for stigmatized individuals as the presence of minority stress, because the chronic threat-vigilance fostered by insufficient safety has negative long-term effects on cognitive, emotional, and immunological functioning, even when exposure to minority stress is low. We argue that insufficient social safety is a primary cause of stigma-related health disparities and a key target for intervention.

Childhood Gender Nonconformity and Recalled Perceived Parental and Peer Acceptance Thereof, Internalized Homophobia, and Psychological Well-Being Outcomes in Heterosexual and Gay Men from Poland

The link between gender nonconformity and psychopathology may be due in part to negative childhood experiences resulting from other people's reactions to gender nonconformity. The aim of this study was to test whether recalled perceived levels of parental and peer acceptance of childhood gender nonconforming behaviors and play mediate the relationship of childhood gender nonconformity with depression and social anxiety in adulthood. We also tested whether this relationship was moderated by sexual orientation and, among gay men, whether internalized homophobia was an additional mediator. All variables were measured in a large sample of male participants using self-report (n = 449 gay men, age: M = 27.8 years, SD = 6.69; and n = 296 heterosexual men, age: M = 27.4 years, SD = 6.57) in Poland. Gay men reported more childhood gender nonconformity than heterosexual men. The relationship between gender nonconformity and depressive symptoms as well as social anxiety symptoms was significant in both gay and heterosexual men. Among gay men, this relationship was partially mediated by peer but not parental acceptance of the measured aspects of gender nonconformity and internalized homophobia. Among heterosexual men, recalled perceived parental acceptance of gender nonconformity partially mediated the relationship between gender nonconformity and depressive and social anxiety symptoms. Our findings were partially in line with those found in Western European and North American samples. Although the two groups differed in their recalled perceived gender nonconformity, they did not differ in their depression or social anxiety scores. Nevertheless, childhood gender nonconformity may be an indirect risk associated with mental health symptoms, irrespective of sexual orientation. Its higher prevalence among nonheterosexual individuals makes it a particular risk for this group.

Mechanisms of Mental-Health Disparities Among Minoritized Groups: How Well Are the Top Journals in Clinical Psychology Representing This Work?

We have known for decades that mental health disparities exist among minoritized groups, including race, ethnicity, sexual identities, gender identity and expression, ability, and others. Theories and frameworks that incorporate stressors unique to the experiences of minoritized groups, such as the biopsychosocial model of racism (Clark et al, 1999) and minority stress model (Meyer, 2003), offer testable mechanisms that may help explain, in part, mental health disparities. However, research addressing mechanisms of these disparities is still scarce and is not well represented in our top clinical psychology journals. This review critically examines the extent to which top tier clinical psychology journals publish work examining mechanisms of mental health disparities among minoritized populations. We find very few studies have been published in top clinical psychology journals that address mechanisms of mental health disparities. We examine potential reasons for this and discuss recommendations for future research.

Examination of Outcomes among Sexual Minorities in Treatment for Obsessive-Compulsive and Related Disorders

The first-line psychological treatment for obsessive-compulsive and related disorders (OCRDs) is exposure and response prevention (ERP). As the first study to examine treatment outcomes for sexual minorities, it is crucial to examine: (1) how treatment-seeking individuals who identify as sexual minorities compare to heterosexual individuals in symptom severity at admission, length of stay in treatment, and (2) whether ERP is equally effective for sexual minorities. The current study explored these questions in an intensive/residential treatment (IRT) program for OCRDs. Adult participants (N = 191) completed self-reported measures of OCD severity, distress tolerance, and depression at program admission, in the first four weeks of treatment, and at discharge. No differences were found between groups for treatment outcome, although slight differences (non-significant) emerged at baseline for OCRD severity, distress tolerance, and depression. Sexual orientation was not predictive of OCRD severity at weeks 1-4, and number of days spent in treatment was not associated with sexual orientation. This is the first study exploring whether sexual orientation is predictive of treatment outcomes for individuals diagnosed with OCRDs. Results suggest that outcomes did not differ and participation in the program resulted in an overall improvement of symptoms regardless of sexual orientation, however several study limitations are discussed. Future studies should replicate these findings, attempt to collect a larger sample, incorporate qualitative feedback from treatment, and examine outcomes in gender minorities.

Increased depressive and anxiety symptoms in non-heterosexual individuals: Moderation by childhood factors using a twin design

BACKGROUND

Evidence indicates that minority stress does not sufficiently explain mental health disparities in non-heterosexual compared to heterosexual individuals. We investigated alternative mechanisms whereby childhood factors (childhood gender nonconformity, early-life adversities and parent-child interactions) moderate the relationships between sexual orientation and depressive and anxiety symptoms.

METHODS

The sample comprised twin pairs from the Finnish Genetics of Sexuality and Aggression cohort (n = 3166 individuals, mean age = 37.5 ± 2.93 years). Twin analyses using structural equation modelling was performed in OpenMx. Specifically, we tested whether childhood factors differentially moderated the underlying genetic and environmental influences on the relationships between sexual orientation, and depressive and anxiety symptoms.

RESULTS

The associations between non-heterosexuality, and depressive and anxiety symptoms (r = 0.09, 0.10 respectively) were significantly influenced by both genetic and environmental factors. The genetic influences explaining the relationships of sexual orientation with depressive and anxiety symptoms were maximal at high levels of childhood gender nonconformity (β_A = 0.09 and 0.11 respectively) whereas the individual-specific environmental influences on these relationships were maximal at lower levels of childhood gender nonconformity (β_E = -0.10).

LIMITATIONS

Childhood factors were assessed retrospectively in a cross-sectional design.

CONCLUSIONS

Childhood gender nonconformity is associated with increased genetic and decreased individual-specific environmental influences on mental health among non-heterosexual individuals. Childhood gender nonconformity may, thus, enhance genetic risk and non-genetic protective processes for depressive and anxiety symptoms among non-heterosexual individuals.

Do psychosocial factors mediate sexual minorities' risky sexual behaviour? A twin study

OBJECTIVES

Risky sexual behavior among sexual minorities (lesbian, gay, and bisexual individuals) are partly attributed to mental health and other social disparities; but this may be confounded by correlated genetic and environmental influences. As preregistered, the present study investigated indirect associations between sexual minority status and increased lifetime sexual partners through increased psychosocial adversity (depressive and anxiety symptoms, intimate partner violence, and early life adversities) and substance use (alcohol, cannabis, and other illicit drugs), confounding by correlated genetic and environmental influences, and sex differences in these relationships.

METHOD

The sample comprised sexual minority and heterosexual twins who participated in the first and second phases of the latest wave of data collection in the U.K. population-based Twins Early Development study cohort (June 2017 through February 2019; n = 9,697 and 8,718, respectively, Mage = 22.3 ± .92 years). Structural equation modeling was used to specify psychosocial adversity and substance use as mediators while genetic and environmental confounding was further determined by biometrical genetic analyses in which similarities in identical and nonidentical twins were compared.

RESULTS

Increased psychosocial adversity and substance use fully mediated increased lifetime sexual partners in sexual minority women while this effect was partial (31.1%) in men. The best-fitting genetic models indicated that these relationships were not confounded by correlated genetic and environmental influences.

CONCLUSIONS

The relationships between sexual minority status, psychosocial adversity, substance use, and sexual health disparities appeared independent of genetic and environmental influences. Individual and systemic interventions to reduce psychosocial disadvantage and substance use can also decrease sexual health disparities among sexual minorities. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Retracted: Sexual orientation, neuropsychiatric disorders and the neurotransmitters involved

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor in Chief of Neuroscience and Biobehavioral Reviews after concerns were raised with respect to the phrasing of comparisons drawn between humans and animal models. These comparisons were deemed unsupportable, and thus in the best interests of publication standards the Editor has concluded it is necessary to retract the paper. The authors disagree with the reason for the retraction.

Impact of the COVID-19 Pandemic on Perceptions of Health and Well-Being Among Sexual and Gender Minority Adolescents and Emerging Adults

Purpose: The study purpose was to examine how the COVID-19 pandemic may be differentially impacting the well-being of sexual and gender minority (SGM) youth compared with their non-SGM counterparts. Specifically, we looked at perceptions of mental and physical health impact and relevant aspects of coping with the pandemic such as engagement in prosocial activities that might ultimately promote resilience. Methods: Survey data were collected between November 27, 2020, and December 11, 2020, from 990 adolescents and emerging adults aged 13-23 years. Participants were recruited through advertisements on Facebook and Instagram with an effort to overrecruit SGM youth. Questions asked youth about their perception of the impact of the COVID-19 pandemic on their physical and mental health, the types of prosocial activities engaged in during the pandemic, and how they felt they were doing now versus before the pandemic. Results: SGM youth reported a significantly greater impact from the pandemic than non-SGM youth. Both SGM youth and cisgender heterosexual females reported greater impact on their mental health compared with cisgender heterosexual males, with cisgender sexual minority females and gender minority youth reporting the highest mental health impact. Gender minority youth also reported feeling less connected to their families and less safe at home as a result of the pandemic. Conclusion: Health professionals, educators, and advocates need to help assess SGM youth for negative impact from the pandemic and help them connect with other youth and support resources online as they move forward. Youth may also benefit from programs connecting them to volunteer work and neighbors.

Systemic inflammation as a driver of health disparities among sexually-diverse and gender-diverse individuals

Sexually-diverse individuals (those who seek sexual or romantic relationships with the same and/or multiple genders) and gender-diverse individuals (those whose gender identity and/or expression differs from their birth-assigned sex/gender) have disproportionately high physical health problems, but the underlying biological causes for these health disparities remain unclear. Building on the minority stress model linking social stigmatization to health outcomes, we argue that systemic inflammation (the body's primary response to both physical and psychological threats, indicated by inflammatory markers such as C-reactive protein and proinflammatory cytokines) is a primary biobehavioral pathway linking sexual and gender stigma to physical health outcomes. Expectations and experiences of social threat (i.e., rejection, shame, and isolation) are widespread and chronic among sexually-diverse and gender-diverse individuals, and social threats are particularly potent drivers of inflammation. We review research suggesting that framing "minority stress" in terms of social safety versus threat, and attending specifically to the inflammatory consequences of these experiences, can advance our understanding of the biobehavioral consequences of sexual and gender stigma and can promote the development of health promoting interventions for this population.

Mental Health Disparities Mediating Increased Risky Sexual Behavior in Sexual Minorities: A Twin Approach

Increased risky sexual behavior in sexual minorities relative to heterosexual individuals may be partly explained by mental health disparities, and both factors may be further jointly influenced by common genetic and environmental factors. However, these relationships have not been previously investigated. The objectives of the present study were to investigate mental health disparities as a mediator of the relationship between sexual orientation and risky sexual behavior, controlling for genetic and environmental effects in this relationship and testing for sex differences. Participants included 5814 twins from a Finnish twin cohort. Specified latent factors included sexual orientation, mental health indicators, and risky sexual behavior. Twin models were fitted to the factor structure of the data whereby a Cholesky decomposition on the factors was compared to a mediation submodel using OpenMx. Sex differences were tested in the final model. Phenotypically, mental health disparities partially mediated the relationship between sexual orientation and increased risky sexual behavior, with comparable effects in males and females. However, while this indirect route from sexual orientation to risky sexual behavior mainly contained transmitted genetic effects in males, there was a significant proportion of transmitted shared environmental effects in females. This is the first study to demonstrate that the mediation relationships between sexual orientation, mental health disparities, and risky sexual behavior are not confounded by genetic and environmental factors. The significant sex differences need to be recognized in future research and intervention design to improve sexual health in sexual minorities.

Handedness and Birth Order Among Heterosexual Men, Gay Men, and Sao Praphet Song in Northern Thailand

Previous research has examined handedness and birth order to inform sexual orientation and gender identity/role expression development; however, sexual orientation and gender identity/role expression have rarely been disentangled to provide a more nuanced perspective. In Thailand, we investigated sexual orientation and gender identity simultaneously via comparison of 282 heterosexual men, 201 gay men, and 178 sao praphet song-i.e., androphilic, markedly feminine males recognized as a "third" gender. Handedness was examined as: extremely left-handed, moderately left-handed, ambidextrous, moderately right-handed, or extremely right-handed. Birth order was examined as numbers of older and younger brothers and sisters, by using Berglin's, fraternal, and sororal indices, and by examining the older brother odds ratio and sibling sex ratio. Compared with heterosexual men, gay men and sao praphet song were more likely to be extremely right-handed. Sao praphet song were also more likely to be extremely left-handed than heterosexual and gay men. Heterosexual men and sao praphet song had later sororal birth order compared with the expected Thai population value, suggesting stopping rules influenced when probands' mothers ceased having children. These findings provide new insights and replicate previous findings in a non-Western sample. Regarding handedness, in males, mechanisms related to extreme right-handedness likely influence the development of androphilia, whereas mechanisms related to both extreme right- and extreme left-handedness likely explain the combination of androphilia and feminine gender identity/role expression. Regarding birth order, similar to the conclusions of some prior research, stopping rules pose a challenge for testing the fraternal birth order effect.

Measuring Adverse Childhood Experiences: Comparing Individual, Composite, Score-based and Latent Profile-based Scoring Schemas Among Gay, Bisexual, and Other Men Who Have Sex with Men

Adverse childhood experiences (ACEs; e.g., neglect, sexual abuse) among gay, bisexual, and other men who have sex with men (GBM) may not occur in isolation, but may be connected and occur in clusters. Most studies have measured ACEs individually, hierarchically, additively, or in a binary fashion (presence or absence of ACEs), rather than treating them as connected and clustered. This study examined these competing approaches of scoring ACEs and their relative power at predicting health outcomes. We examined abuse (sexual, physical, and emotional) and neglect (physical and emotional) experiences among a non-random sample of 470 Toronto GBM using the Childhood Trauma Questionnaire Short Form subscales. We compared five scoring schemas: (1) five individual scores for each form of maltreatment; (2) a composite score summing all of the maltreatment scores; (3) a hierarchical regression model with sexual abuse entered first then followed by physical abuse, emotional abuse, physical neglect, and emotional neglect; (4) a severity-based categorization; and (5) a latent profile-based categorization. Experiences of abuse and neglect were not uncommon (22-33%) and some participants experienced multiple forms of abuse and neglect (r = .33-.65, df = 464-467; p < .001; shared variance, r² = 11-43%). Results show the dose-response effects of ACEs and highlight the importance of examining ACEs in clusters rather than individually. Latent profile analysis identified GBM who experienced multiple and frequent ACEs, and also identified the types of ACEs they experienced: crucial information that was obscured in score-based or severity-based approaches.

Nick Martin's Contributions to Human Sexuality Research

Genetic research into human sexuality was scarce at the end of last century. In 1992 Nick developed a 12-page questionnaire to send to twins to investigate the underpinnings of sexuality. The questionnaire included items about sexual orientation, sociosexuality and sexual behavior, and was completed by almost 5000 twins. The resulting data, unique at the time, has been used to investigate many previously unexaminable research questions. Here we describe how Nick's questionnaire contributed to our understanding of human sexuality and how we got involved in this endeavor.

Psychiatric disorders, suicidality, and personality among young men by sexual orientation

Personality and its potential role in mediating risk of psychiatric disorders and suicidality are assessed by sexual orientation, using data collected among young Swiss men (n = 5875) recruited while presenting for mandatory military conscription. Mental health outcomes were analyzed by sexual attraction using logistic regression, controlling for five-factor model personality traits and socio-demographics. Homo/bisexual men demonstrated the highest scores for neuroticism-anxiety but the lowest for sociability and sensation seeking, with no differences for aggression-hostility. Among homo/bisexual men, 10.2% fulfilled diagnostic criteria for major depression in the past 2 weeks, 10.8% for ADHD in the past 12 months, 13.8% for lifetime anti-social personality disorder (ASPD), and 6.0% attempted suicide in the past 12 months. Upon adjusting (AOR) for personality traits, their odds ratios (OR) for major depression (OR = 4.78, 95% CI 2.81–8.14; AOR = 1.46, 95% CI 0.80–2.65) and ADHD (OR = 2.17, 95% CI = 1.31–3.58; AOR = 1.00, 95% CI 0.58–1.75) lost statistical significance, and the odds ratio for suicide attempt was halved (OR = 5.10, 95% CI 2.57–10.1; AOR = 2.42, 95% CI 1.16–5.02). There are noteworthy differences in personality traits by sexual orientation, and much of the increased mental morbidity appears to be accounted for by such underlying differences, with important implications for etiology and treatment.

Research on Relationships between Sexual Identity, Adverse Childhood Experiences and Non-Suicidal Self-Injury among Rural High School Students in Less Developed Areas of China

Purpose: The objective of this study was to examine the influence of sexual identity and adverse childhood experiences (ACEs) on non-suicidal self-injury (NSSI) among rural high school students in less developed areas of China. Methods: Behavior risk factors data collected from 1810 students from a high school in Jiangxi province, China. Five measures of childhood abuse and household dysfunction were summarized, and ACE was divided into 0, 1, 2, 3–5 ACEs. Logistic regression analysis was used to explore the influence of sexual identity, adverse childhood experiences, and their interaction with non-suicidal self-injury. Results: Compared with heterosexual students, high school students who identify as lesbian, gay, or bisexual (LGB) have a higher tendency of non-suicidal self-injury (AOR = 3.250, 95% CI = 1.69–6.28, p < 0.01). There was also a graded relationship between cumulative ACEs exposure and non-suicidal self-injury behaviors (AOR = 1.627, 95% CI = 1.02–2.60, p < 0.05). Odds for NSSI are higher among students with both experienced ACEs and identified as LGB (AOR = 2.821, 95% CI = 1.51–5.29, p < 0.05). Conclusions: Non-suicidal self-injury is associated with ACEs exposure and with those who identify as LGB, and the NSSI odds are greater when students identify as LGB and have experienced ACEs. More interventions to reduce non-suicidal self-injury should focus on LGB and ACEs and more attention needs to be paid to those who identify as LGB and have been exposed to ACEs.

Sexual identity, same-same relationships, and health dynamics: New evidence from Australia

Prior research has found that opposite-sex marital and cohabiting relationships are associated with improvements in health. However, studies examining the health dynamics of same-sex relationships are sparser because few nationally representative longitudinal datasets collect information on adults' sexual identity. Using newly available data on sexual minorities from the Household, Income and Labour Dynamics in Australia (HILDA) Survey, we estimate the effects of Lesbian/Gay/Bisexual (LGB) identification and same-sex relationships on health dynamics. We document two key findings. First, sexual minorities in Australia are more likely to engage in risky health behaviors and report worse health than their heterosexual counterparts. Second, after exploiting the longitudinal nature of the HILDA and accounting for selection into relationships using the dynamic panel approach of Kohn and Averett (2014), we find that while opposite-sex partnerships are associated with a 3 to 7 percentage-point decline in risky health behaviors and improved physical and mental health, the health benefits of same-sex relationships are weaker, particularly for men.

Cortical brain structure and sexual orientation in adult females with bipolar disorder or attention deficit hyperactivity disorder

BACKGROUND

Nonheterosexual individuals have higher risk of psychiatric morbidity. Together with growing evidence for sexual orientation-related brain differences, this raises the concern that sexual orientation may be an important factor to control for in neuroimaging studies of neuropsychiatric disorders.

METHODS

We studied sexual orientation in adult psychiatric patients with bipolar disorder (BD) or ADHD in a large clinical cohort (N = 154). We compared cortical brain structure in exclusively heterosexual women (HEW, n = 29) with that of nonexclusively heterosexual women (nHEW, n = 37) using surface-based reconstruction techniques provided by FreeSurfer.

RESULTS

The prevalence of nonheterosexual sexual orientation was tentatively higher than reported in general population samples. Consistent with previously reported cross-sex shifted brain patterns among homosexual individuals, nHEW patients showed significantly larger cortical volumes than HEW in medial occipital brain regions.

CONCLUSION

We found evidence for a sex-reversed difference in cortical volume among nonheterosexual female patients, which provides insights into the neurobiology of sexual orientation, and may provide the first clues toward a better neurobiological understanding of the association between sexual orientation and mental health. We also suggest that sexual orientation is an important factor to consider in future neuroimaging studies of populations with certain mental health disorders.

Minority stressors, rumination, and psychological distress in monozygotic twins discordant for sexual minority status

BACKGROUND

Lesbian, gay, and bisexual (LGB) individuals report higher levels of depression and anxiety than heterosexual people. Genetic factors may be a 'common cause' of sexual minority status and psychological distress. Alternatively, these may be correlated because of non-genetic environmental factors (e.g. minority stressors). This study investigated minority stressors and distress in monozygotic twins discordant for sexual minority status. This design provides a test of the role of non-shared environmental factors while minimizing differences due to genetics.

METHODS

Thirty-eight twin pairs in which one was heterosexual and the other was LGB completed a survey. Differences between twin pairs in minority stressors, rumination, psychological distress, and gender non-conformity were examined. Associations between these variables were also tested.

RESULTS

Although there were no significant group differences for distress, LGB twins had higher rumination, a vulnerability factor for distress, than heterosexual co-twins. LGB twins also had higher scores than heterosexual co-twins on expectations of rejection, active concealment, self-stigma, prejudice events, childhood gender non-conformity, and lower scores on sexual orientation disclosure. Differences between twin pairs in rumination were positively associated with differences in acceptance concerns and self-stigma. Finally, self-stigma was positively associated with rumination in the full sample of heterosexual co-twins and microaggressions were positively associated with rumination when looking at exclusively heterosexual co-twins.

CONCLUSIONS

These results support environmental factors as a causal explanation for disparities in rumination between LGB and heterosexual individuals. These factors likely include minority stressors. Rumination may also be associated with minority stressors in heterosexual MZ co-twins of LGB individuals.

Challenges in Taking Sexual History: A Qualitative Study of Indian Postgraduate Psychiatry Trainees

CONTEXT

In India, psychiatrist is an important point of helpseeking for sexual complaints. A detailed sexual history can go a long way in understanding sexual difficulties. In this background, there is inadequate information on the difficulties that psychiatry postgraduate trainees experience while taking a sexual history as part of a routine mental health evaluation.

AIMS

The aim was to study the difficulties experienced by postgraduate psychiatry trainees while taking sexual history as a part of routine mental health evaluation.

SETTING

This study was conducted in an Indian medical college general hospital psychiatry setting.

MATERIALS AND METHODS

This is a qualitative study using focus group discussions and in-depth interviews with postgraduate psychiatry trainees.

STATISTICAL ANALYSIS

Content analysis was used to identify direct and latent themes.

RESULTS

Thematic saturation was achieved with 17 participants. Major themes of difficulties that emerged included trainee-related factors such as gender and sociocultural background of the trainee; patient-related factors such as age, gender, and sexual orientation; setting-related factors; and language-related difficulties.

CONCLUSIONS

Specific and regular training in taking a sexual history is essential in addressing the difficulties faced by postgraduate psychiatry trainees in India.

The Relationship Between Indicators of Depression and Anxiety and Sexual Orientation in Canadian Women

Previous studies examining the associations between women's sexual orientation and mental health have obtained inconsistent results. Whereas some studies have suggested that status as a lesbian or bisexual woman may be associated with greater mental health risk, others have suggested that bisexual women may be specifically vulnerable to mental health problems. The current study examined two competing models in a non-clinical sample of Canadian women (N = 278). The first model predicted that women who reported bisexual attraction would endorse more indicators of depression and anxiety compared to women who reported monosexuality (either same- or opposite-sex attraction). The second model predicted that women who reported relatively greater same-sex attraction would exhibit elevated indicators of depression and anxiety compared to women who reported opposite-sex attraction. Consistent with Model 1, greater bisexual attraction predicted greater endorsement of indicators of depression and anxiety compared to greater same-sex or opposite-sex attraction. These findings suggest that, in women, bisexuality may be associated with higher risk of depression and anxiety than monosexuality. Future research may benefit from exploring risk factors potentially unique to the mental health of bisexual women.

Fraternal Birth Order, Family Size, and Male Homosexuality: Meta-Analysis of Studies Spanning 25 Years

The fraternal birth order effect is the tendency for older brothers to increase the odds of homosexuality in later-born males. This study compared the strength of the effect in subjects from small versus large families and in homosexual subjects with masculine versus feminine gender identities. Meta-analyses were conducted on 30 homosexual and 30 heterosexual groups from 26 studies, totaling 7140 homosexual and 12,837 heterosexual males. The magnitude of the fraternal birth order effect was measured with a novel variable, the Older Brothers Odds Ratio, computed as (homosexuals' older brothers ÷ homosexuals' other siblings) ÷ (heterosexuals' older brothers ÷ heterosexuals' other siblings), where other siblings = older sisters + younger brothers + younger sisters. An Older Brothers Odds Ratio of 1.00 represents no effect of sexual orientation; values over 1.00 are positive evidence for the fraternal birth order effect. Evidence for the reliability of the effect was consistent. The Older Brothers Odds Ratio was significantly >1.00 in 20 instances, >1.00 although not significantly in nine instances, and nonsignificantly <1.00 in 1 instance. The pooled Older Brothers Odds Ratio for all samples was 1.47, p < .00001. Subgroups analyses showed that the magnitude of the effect was significantly greater in the 12 feminine or transgender homosexual groups than in the other 18 homosexual groups. There was no evidence that the magnitude of the effect differs according to family size.

Does Sexual Orientation Precede Childhood Sexual Abuse? Childhood Gender Nonconformity as a Risk Factor and Instrumental Variable Analysis

Research suggests that there is a relation between childhood sexual abuse (CSA) and adulthood nonheterosexual orientation. To explore whether nonheterosexual orientation increases the risk of CSA, we recruited a large sample, added the variable of childhood gender nonconformity (CGNC), and applied the instrumental variable method. We found that heterosexual and nonheterosexual men who were more gender nonconforming in childhood were significantly more likely to report having a history of CSA than their gender-conforming counterparts. There was no relation between CSA and CGNC for heterosexual and nonheterosexual women. The instrumental variable analysis revealed that the increased prevalence of CSA experienced by nonheterosexuals compared with heterosexuals may be due to the influence of sexual orientation on CSA. In sum, the results suggest that nonheterosexuality may increase the risk of childhood sexual abuse.

Sex, Sexual Orientation, Gender Atypicality, and Indicators of Depression and Anxiety in Childhood and Adulthood

The current study evaluated the possibility that greater negative mental health outcomes reported among gay, lesbian, and gender-atypical individuals, compared to gender-typical individuals, are present in childhood and persist into adulthood. Sex and sexual orientation differences in self-reported adulthood and recalled childhood indicators of depression and anxiety and their association with current and retrospectively reported gender (a)typicality were examined in a non-clinically recruited community sample of Canadian heterosexual men (n = 98), heterosexual women (n = 142), gay men (n = 289), and lesbian women (n = 69). Indicators of depression and anxiety were constructed based on diagnostic criteria for generalized anxiety disorder, major depression, agoraphobia, social anxiety disorder, panic disorder, obsessive-compulsive disorder, and specific phobias. Factor reduction analyses yielded three factors: (1) indicators of childhood separation anxiety, (2) indicators of childhood depression and anxiety, and (3) indicators of adulthood depression and anxiety. Lesbian women scored higher on childhood separation anxiety than all other groups. Heterosexual men scored lower on indicators of childhood separation anxiety than gay men and lower on indicators of childhood and adulthood depression and anxiety than all other groups. No other significant group differences were observed. Correlational analysis suggested that for men, but not for women, gender-atypical behavior was associated with negative mental health. The current study indicated that childhood should be considered a critical time period during which the noted sexual orientation-related mental health discrepancies manifest and that childhood gender atypicality is a key factor for understanding the emergence of such discrepancies.

Fraternal Birth Order, Handedness, and Sexual Orientation in a Chinese Population

We examined the relationship between handedness, fraternal birth order, and sexual orientation in a Chinese population, and analyzed the influence of the components assessing sexual orientation and criteria classifying individuals as homosexual on this relationship. A large sample of heterosexual, bisexual, and homosexual men and women participated in a web-based survey. Our results showed that homosexual women are more likely to be non-right-handed than heterosexual women, regardless of how sexual orientation was defined, whereas bisexual women are more likely to be non-right-handed than heterosexual women when sexual orientation was assessed via sexual attraction and sexual identity. Bisexual men are more likely to be non-right-handed than heterosexual men when sexual orientation was assessed via sexual attraction. We found neither a fraternal birth-order effect nor an interaction between sibling sex ratio, handedness, and sexual orientation. The small number of siblings may be the reason why we could not replicate the fraternal birth-order effect in this Chinese population, which highlights the importance of cultural differences in the understanding of handedness, fraternal birth order, and sexual orientation.

Familial Factors, Victimization, and Psychological Health Among Sexual Minority Adolescents in Sweden

OBJECTIVES

To determine the influences of victimization experience and familial factors on the association between sexual minority status and psychological health outcomes among adolescents.

METHODS

We used data from the Child and Adolescent Twin Study in Sweden, a prospective, population-based study of all twins born in Sweden since 1992. Cross-sectional analyses included individuals who completed assessments at age 18 years (n = 4898) from 2000 to 2013. We also compared psychological health among sexual minority adolescents and their nonminority co-twins.

RESULTS

Sexual minority adolescents were more likely than were unrelated nonminority adolescents to report victimization experiences, including emotional abuse, physical abuse or neglect, and sexual abuse. Sexual minority adolescents also reported significantly more symptoms of anxiety, depression, attention-deficit/hyperactivity disorder, disordered eating, and substance misuse in addition to increased parent-reported behavior problems. Victimization experience partially mediated these associations. However, when controlling for unmeasured familial confounding factors by comparing sexual minority adolescents to their same-sex, nonminority co-twins, the effect of sexual minority status on psychological health was almost entirely attenuated.

CONCLUSIONS

Familial factors-common genetic or environmental influences-may explain decreased psychological adjustment among sexual minority adolescents.

Sexual Orientation, Controversy, and Science

Summary

Ongoing political controversies around the world exemplify a long-standing and widespread preoccupation with the acceptability of homosexuality. Nonheterosexual people have seen dramatic surges both in their rights and in positive public opinion in many Western countries. In contrast, in much of Africa, the Middle East, the Caribbean, Oceania, and parts of Asia, homosexual behavior remains illegal and severely punishable, with some countries retaining the death penalty for it. Political controversies about sexual orientation have often overlapped with scientific controversies. That is, participants on both sides of the sociopolitical debates have tended to believe that scientific findings—and scientific truths—about sexual orientation matter a great deal in making political decisions. The most contentious scientific issues have concerned the causes of sexual orientation—that is, why are some people heterosexual, others bisexual, and others homosexual? The actual relevance of these issues to social, political, and ethical decisions is often poorly justified, however.