RESUMEN
BACKGROUND: Suicide is a leading cause of death in individuals with psychotic disorders. Risk factors for suicidality across the psychosis vulnerability spectrum are insufficiently known. METHODS: For patients (n = 830), siblings (n = 664) and controls (n = 444), suicidality was assessed by the use of a clinical interview. Multilevel modelling was used to investigate risk factors of suicidality. Lastly, risk factor × familial risk interaction effects were examined. RESULTS: Multivariable models revealed a significant relation between suicidality and depressive symptoms across all three groups, and childhood trauma in patients and siblings. The association between suicidality and psychotic-like experiences is more pronounced in siblings compared to controls. CONCLUSION: Across the psychosis vulnerability spectrum, depressive symptoms and childhood trauma have been associated with suicidality. Clinicians should pay attention to suicidality in individuals at high familial risk for psychosis with psychotic-like experiences.