Early Parental Death and Risk of Psychosis in Offspring: A Six-Country Case-Control Study.

Evidence for early parental death as a risk factor for psychosis in offspring is inconclusive. We analyzed data from a six-country, case-control study to examine the associations of early parental death, type of death (maternal, paternal, both), and child's age at death with psychosis, both overall and by ethnic group. In fully adjusted multivariable mixed-effects logistic regression models, experiencing early parental death was associated with 1.54-fold greater odds of psychosis (95% confidence interval (CI): 1.23, 1.92). Experiencing maternal death had 2.27-fold greater odds (95% CI: 1.18, 4.37), paternal death had 1.14-fold greater odds (95% CI: 0.79, 1.64), and both deaths had 4.42-fold greater odds (95% CI: 2.57, 7.60) of psychosis compared with no early parental death. Experiencing parental death between 11 and 16 years of age had 2.03-fold greater odds of psychosis than experiencing it before five years of age (95% CI: 1.02, 4.04). In stratified analyses, experiencing the death of both parents had 9.22-fold greater odds of psychosis among minority ethnic groups (95% CI: 2.02-28.02) and no elevated odds among the ethnic majority (odds ratio (OR): 0.96; 95% CI: 0.10-8.97), which could be due in part to the higher prevalence of early parental death among minority ethnic groups but should be interpreted cautiously given the wide confidence intervals.