Incidence of Suicide Among Persons Who Had a Parent Who Died During Their Childhood: A Population-Based Cohort Study

Abstract

Importance: Parental death from suicide is associated with increased risk of suicide in the bereaved child, but little is known about the long-term risks of suicide after parental death from other causes. A better understanding of this association may improve suicide prevention efforts.

Objective: To examine the long-term risks of suicide after parental death and how the risk trajectories differed by cause of parental death while accounting for major potential confounding variables.

Design, setting, and participants: A population-based matched cohort study was performed using information from nationwide registers (data from 1968 to 2008) in 3 Scandinavian countries (for a total of 7,302,033 persons). We identified 189,094 children (2.6%) who had a parent who died before the child reached 18 years of age (ie, the bereaved cohort). Each bereaved child was matched by sex and age to 10 children who did not have a parent who died before they reached 18 years of age (for a total of 1,890,940 children) (ie, the reference cohort). Both cohorts were followed for up to 40 years. Poisson regression was used to calculate the incidence rate ratio (IRR), while accounting for age at parental death, sex, time since bereavement, maternal/paternal death, birth order, family history of psychiatric illness, and socioeconomic status. Data analyses were finalized June 24, 2015.

Exposure: The main exposure was death of a parent within the first 18 years of life.

Main outcomes and measures: Incidence of suicide among persons who had a parent who died during their childhood.

Results: During follow-up, 265 bereaved persons (0.14%) and 1342 nonbereaved persons (0.07%) died of suicide (IRR = 2.02 [95% CI, 1.75-2.34]); IRR = 3.44 (95% CI, 2.61-4.52) for children who had a parent who died of suicide, and IRR = 1.76 (95% CI, 1.49-2.09) for children who had a parent who died of other causes. The IRR tended to be higher for children who had a parent who died before they reached 6 years of age, and the IRR remained high for at least 25 years. During 25 years of follow-up, the absolute risk of suicide was 4 in 1000 persons for boys who experienced parental death and 2 in 1000 persons for girls who experienced parental death.

Conclusions and relevance: Parental death in childhood is, irrespective of cause, associated with an increased long-term risk of suicide. The consequences of parental death in childhood are far-reaching, and suicide risk trajectories may be influenced by early-life conditions. Future public health efforts should consider helping highly distressed children to cope with bereavement.