To Örebro University

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.