Psychiatric morbidity associated with same-sex sexual behaviour: influence of minority stress and familial factors

Background. Increased psychiatric morbidity has been widely reported among non-heterosexual individuals (defined as reporting a homosexual/bisexual identity and/or same-sex sexual partners). However, the causes of this psychiatric ill-health are mostly unknown. Method. We attempted to estimate the influence Of minority stress and familial factors on psychiatric disorder among adults with same-sex sexual partners. Self-report data from a 2005 survey of adults (age 20-47),cars, n = 17 379) in the population-based Swedish Twin Registry were analysed with regression modelling and co-twin control methodology. Results. Rates of depression, generalized anxiety disorder (GAD), eating disorders, alcohol dependence and attention deficit hyperactivity disorder (ADHD) were increased an-tong men and women with same-sex sexual experiences. Adjusting for perceived discrimination and hate crime victimization lowered this risk whereas controlling for familial (genetic or environmental) factors in within-twin pair comparisons further reduced Or estimated it. Conclusions. Components of minority stress influence the risk of psychiatric ill-health among individuals with any same-sex sexual partner. However, substantial confounding by familial factors suggests, a common genetic and/or environmental liability for same-sex sexual behaviour and psychiatric morbidity.