Suicidal thoughts and behaviours in Cape Town: a cross-sectional study of prevalence and social, contextual, and clinical correlates

Suicidal thoughts and behaviours (STBs) are traditionally attributed to mental disorders; however, increasing evidence indicates that social determinants contribute to suicide risk. We examined STBs and their socioeconomic, psychosocial and clinical correlates in two communities in Cape Town. We conducted psychiatric diagnostic interviews (MINI) at three public-sector facilities (2023-2024). Adults aged ≥18 years, with and without HIV, were recruited in a 2:1 ratio. We examined associations between suicidal ideation and sociodemographic factors, violence exposure, perceived stress, mental disorders, and HIV, reporting average marginal effects (AME) as percentage-point differences in predicted probability. We enrolled 613 participants (63.9% female; 65.4% living with HIV; median age 39). The prevalence of past 30-day suicidal ideation was 14.0%, while 22.2% reported a lifetime suicide attempt. Suicidal ideation was more likely among females (8.52 percentage points, 95% CI 3.08 –13.96), those reporting violence in the community (7.52, 0.87–14.17) or in the family (14.09, 4.56 –23.62), those with moderate (7.76, 2.76 –12.77) or high perceived stress (33.58, 20.67– 46.50), and those with depression (27.13, 14.67– 39.58), post-traumatic stress disorder (27.98, 12.12 – 43.84), or alcohol use disorder (8.34, 1.53 –15.15). Associations with high perceived stress and community violence persisted after adjustment for mental disorders. HIV status and other sociodemographic factors showed no evidence of association. STB prevalence was high in peri-urban communities in Cape Town and strongly associated with mental disorders, violence exposure, and perceived stress. These findings underscore the role of structural and psychosocial stressors in shaping suicide risk in low-income communities. • Suicidal thoughts and behaviours are highly prevalent in peri-urban areas in Cape Town • Mental disorders are the strongest correlates of suicidal ideation • Violence and perceived stress are independently associated with suicidal ideation • HIV is not significantly associated with suicidal ideation • Suicide prevention requires interventions addressing mental health and social drivers