Background As part of a systemic effort of assimilation between the late 19^th and mid-20^th centuries, thousands of American Indian/Alaska Native (AIAN) children were placed in residential Indian boarding schools. To understand the impact of forced attendance in Indian boarding schools on HIV risk, we explored sexual risk behaviours, STI diagnosis, and substance misuse among AIAN two-spirit (gay, lesbian, bisexual, and transgender) adults who had attended Indian boarding school as children compared to those with no history of boarding school.

Methods The current investigation was part of a comprehensive multi-site, cross-sectional national health survey of 447 AIAN two-spirit people from seven metropolitan areas in the U.S. To minimise selection bias, multiple sampling strategies were used including targeted, partial network, and respondent-driven sampling (RDS) techniques.

Results Eighty-two (22.9%) respondents had a history of Indian boarding school attendance. Compared to others, respondents who attended boarding school were more likely to have a diagnosis of alcohol abuse or dependence (58.5% vs. 44.9%, p < 0.05) and reported higher illicit drug use in the past 12 months including: club drugs (18.3% vs. 9.6%, p < 0.05), crack-cocaine (43.9% vs. 29.6%, p < 0.01), and erectile dysfunction drugs (7.3% vs. 2.7%, p < 0.05). Former boarding school attendees also reported more lifetime partners (5.9 vs. 5.4, p < 0.05), were more likely to have had an STI (42.7% vs. 30.7%, p < 0.05), and were more likely to have ever traded sex for drugs, money, or food (56.8% vs. 33.5%, p < 0.001).

Conclusion Findings from this study provide some of the first data on boarding school experience and HIV risk among an urban two-spirit AIAN community sample and underscore the need for increased HIV/STI prevention efforts in AIAN communities. In addition, advanced statistical models are needed that identify mediational pathways to health outcomes and risk behaviours.