Offspring death and subsequent psychiatric morbidity in bereaved parents: addressing mechanisms in a total population cohort

Abstract

Background It is unclear if psychiatric morbidity among parents bereaved of a child is related to major loss in general or if the cause of death matters. Whether such a link is consistent with a causal explanation also remains uncertain. Method We identified 3,114,564 parents through linkage of Swedish nationwide registers. Risk of psychiatric hospitalization was assessed with log-linear Poisson regression and family-based analyses were used to explore familial confounding. Results A total of 3284 suicides and 14,095 any-cause deaths were identified in offspring between 12 and 25 years of age. Parents exposed to offspring suicide had considerably higher risk of subsequent psychiatric hospitalization than unexposed parents [relative risk (RR) 1.90, 95% confidence interval (CI) 1.72-2.09], higher than parents exposed to offspring non-suicide death relative to controls (RR 1.18, 95% CI 1.11-1.26). We found no risk increase among stepfathers differentially exposed to biologically unrelated stepchildren's death or suicide, and the relative risk was notably lower among full siblings differentially exposed to offspring death or suicide. Conclusions Parental psychiatric hospitalization following offspring death was primarily found in offspring suicide. Familial (e.g. shared genetic) effects seemed important, judging from both lack of psychiatric hospitalization in bereaved stepfathers and attenuated risk when bereaved parents were contrasted to their non-bereaved siblings. We conclud…