Childhood trauma and bullying-victimization as an explanation for differences in mental disorders by sexual orientation.

Sexual minority individuals are more likely to have mental disorders, including mood, anxiety, and substance use disorders, compared to heterosexual individuals. Whether experiencing trauma or bullying-victimization during childhood explains these differences is currently unclear. We used a psychiatric epidemiological general population-based study to assess whether childhood trauma severity and bullying-victimization before age 16 explains the difference by sexual attraction in mental disorders. Data from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2; N = 6392) were used to examine (1) whether same/both-sex attraction and predominantly other-sex attraction is linked to self-reports of childhood trauma (types and severity) and bullying-victimization, and (2) whether these experiences explain differences between these groups in lifetime and 12-month prevalence of DSM-IV disorders assessed by the Composite International Diagnostic Interview 3.0. Same/both-sex attracted individuals reported a higher childhood trauma severity score compared to exclusively other-sex attracted individuals (B = 0.93, SE = 0.20, p < .001), and were more likely to report bullying-victimization (OR = 2.51 95%CI[1.68, 3.74]). DSM-IV disorders were more prevalent among same/both-sex attracted individuals than among exclusively other-sex attracted individuals (ORs ranged from 1.57 to 4.68). There were no differences in DSM-IV disorders for predominantly other-sex attracted individuals. Childhood trauma severity explained between 9.0% and 57.0% of significant indirect associations between same/both-sex attraction and DSM-IV disorders. Sexual minority individuals experience more types of, and more severe childhood trauma, and are more likely to experience bullying-victimization. These negative experiences partly explained disparities in mental disorders.