Bisexual adolescents' and young adults' risk for depression and suicidal ideation: Developmental trajectories, risk and protective factors, and underlying mechanisms

Modified Project Summary/Abstract Section Bisexual people are disproportionately affected by depression and suicidal ideation (SI) relative to both heterosexual and gay/lesbian people. Rates of depression and SI are highest during adolescence and young adulthood, coinciding with peaks in stressors. Despite evidence that bisexual people outnumber gay/lesbian people and experience a greater mental health burden, bisexual people remain underrepresented in research and there are major gaps in our understanding of their risk for depression and SI. In particular, the mental health disparities affecting bisexual people begin in adolescence, but little is known about developmental trajectories of depression and SI in this population. By examining the heterogeneous trajectories of depression and SI among bisexual adolescents and young adults, we can identify those at greatest risk and pinpoint critical periods when depression and SI peak and increase most rapidly to determine when and with whom to intervene. Further, most prior studies of bisexual people’s mental health have been cross-sectional studies of adults, limiting our understanding of developmental changes in depression and SI in this population, risk and protective factors related to such changes, and underlying mechanisms. Last, people of color (POC) and females are especially likely to identify as bisexual, and they experience unique risk and protective factors, but little is known about the unique influences on depression and SI in these subgroups. Given these gaps, to better understand and address the mental health disparities affecting bisexual people, the proposed R01 will use an accelerated longitudinal design to examine risk for depression and SI from adolescence to young adulthood among bisexual people. Compared to a traditional longitudinal design, which follows a single group for the entire age range of interest, an accelerated longitudinal design recruits multiple groups, each starting at a different age. It is ideal for examining developmental change because of its ability to span the age range of interest in less time than would be possible with a single group. We will recruit a cohort of 500 bisexual people with equal proportions of participants ages 14-23 (n = 50 per age; 50% male, 50% female; 25% White, 25% Black, 25% Hispanic, and 25% other POC). Data will be collected at 5 biannual assessments (baseline, 6-, 12-, 18-, 24-months) and used to accomplish three specific aims: (1) Identify heterogeneous trajectories of depression and SI from adolescence to young adulthood among bisexual people; (2) Examine risk factors for depression and SI and their underlying mechanisms across development; and (3) Examine protective factors as buffers of the associations between risk factors and depression and SI. The proposed R01 will provide essential insights into developmental changes in risk for depression and SI among bisexual people, which is critical for developing tailored interventions to reduce the mental health disparities affecting this population.