Sexual minorities are at increased risk of suicide; however, it is unclear whether there are within-sexual minority differences in risk across specific sexual identities-notably between bisexual and lesbian/gay subgroups. We therefore conducted a systematic review and meta-analysis to quantify associations between bisexual identity and self-reported suicide ideation and attempt and the moderation of these associations by gender/sex, age, sampling strategy, and measurement of sexuality. Abstracts and full texts were independently screened by two reviewers, resulting in a total of 46 studies that met inclusion criteria and reported 12-month or lifetime prevalence estimates for suicide ideation or attempt. A consistent gradient was observed across all four outcomes, whereby bisexual respondents reported the highest proportion of suicide ideation or attempt, lesbian/gay respondents the next highest proportion, and heterosexual respondents the lowest proportion. Random-effects meta-analysis comparing bisexual individuals with lesbian/gay individuals yielded odds ratios (ORs) ranging between 1.22-1.52 across the four outcomes examined. Between-study variability in ORs was large. Thirty-one percent of heterogeneity was explained by sample type (e.g., probability vs. non-probability) and 17% by gender/sex. ORs were consistently larger for women (range: 1.48-1.95, all statistically significant at p < .05) than for men (range: 1.00-1.48, all p > .05), suggesting that gender/sex moderates the association between bisexual identity and suicide risk. Within-sexual minority differences in suicide risk may be attributed to structural and interpersonal experiences of monosexism, bisexual erasure and invisibility, or lack of bisexual-affirming social support, each of which may be experienced differently across gender/sex identities.
Keywords: Bisexual; Mental health; Meta-analysis; Sexual orientation; Suicide.