Risk of self-harm and suicide on reaching the age at which a parent died by suicide or other causes: A Danish, population-based self-controlled case series study

Introduction: Risk factors for suicide after parental suicide may include points in the lifecourse when reminders of the deceased trigger grief resurgence. We hypothesized that risk of suicide attempt and suicide is elevated among suicide-bereaved offspring on reaching the age at which a parent died by suicide. Methods: We conducted a self-controlled case series (SCCS) study using national register data on all individuals bereaved by parental suicide living in Denmark from 1980 to 2016. We compared relative incidence of our combined outcome (any secondary-care episode of self-harm or suicide) during the exposure period (2 years centred on the birthday representing age correspondence) and the 15-year unexposed periods either side. We repeated these models for offspring bereaved by parental non-suicide death as an indirect comparison. Results: Risk of self-harm or suicide was elevated on reaching the age at parental suicide (n = 188; IRR_adj: 2.02, 95% CI: 1.21–3.38) relative to flanking periods, but not at parental non-suicide death (n = 734; IRR_adj: 0.76; 95% CI: 0.39–1.50). Conclusions: Reaching the age at which a parent died by suicide appears to represent a vulnerable period for suicidality, countering public perceptions that time heals linearly. This indicates a need for support in the lead up to age correspondence.