Sexual orientation disparities in substance abuse in a sample of patients engaged in care at an urban community health center: The mediating roles of childhood abuse and intimate partner violence

Background: This study sought to examine disparities in substance abuse by sexual orientation and investigate the mediating roles of childhood abuse < age 15 (CA) and intimate partner violence (IPV) among patients engaged in care at an urban community health center. Methods: Data were from 2,653 patients at Fenway Health in Boston, Massachusetts (mean age 32.0; 78.6% White non-Hispanic; 67.0% male; 12% < high school/GED, 31% some college, and 57% > college degree). Multivariable logistic regression models adjusted for age, sex, race/ethnicity, and educational attainment examined lifetime substance abuse history (yes/no) alongside sexual orientation (49% gay/lesbian, 6% bisexual, 6% other sexual orientation, 39% heterosexual) and violence indicators (CA and IPV). Mediational effects were quantified to estimate the percent of effect explained by violence indicators. Results: Overall, 17.1% of the sample had a history of substance abuse, 19.9% reported childhood abuse < age 15, and 12.9% IPV. Violence indicators were highly associated with substance abuse (p<0.0001), as was identifying as gay/lesbian compared to heterosexual (p<0.0001). CA mediated the relationship between being gay/lesbian versus heterosexual and substance abuse (explicated 23.7%; p=0.0009). IPV mediated the relationship between CA and substance abuse (accounted for 20.0%; p<0.0001), as well as being gay/lesbian versus heterosexual (explained 21.1% p=0.02). Conclusions: CA and IPV experiences partly explain disparities in substance abuse by sexual orientation in this sample of patients engaged in care in an urban setting. Clinicians should assess history of CA and IPV among sexual minorities presenting with a history of substance abuse disorders.