Mortality in parents after death of a child in Denmark: a nationwide follow-up study.

BACKGROUND Little is known about the effect of parental bereavement on physical health. We investigated whether the death of a child increased mortality in parents. METHODS We undertook a follow-up study based on national registers. From 1980 to 1996, we enrolled 21062 parents in Denmark who had a child who had died (exposed cohort), and 293745 controls--ie, parents whose children were alive, and whose family structure matched that of the exposed cohort. Natural deaths were defined with ICD8 codes 0000-7969 and ICD10 codes A00-R99, and unnatural deaths with codes 8000-9999 and V01-Y98. We used Cox's proportional-hazards regression models to assess the mortality rate of parents up to 18 years after bereavement. FINDINGS We observed an increased overall mortality rate in mothers whose child had died (hazards ratio 1.43, 95% CI 1.24-1.64; p<0.0001). An excess mortality from natural causes (1.44, 1.15-1.78; p<0.0001) was noted in mothers only during the 10th-18th year of follow-up. Mothers had increased mortality rates from unnatural causes throughout follow-up, with the highest rate recorded during the first 3 years (3.84, 2.48-5.88; p<0.0001). Bereaved fathers had only an early excess mortality from unnatural causes (1.57, 1.06-2.32; p=0.04). Mothers who lost a child due to an unnatural death or an unexpected death had a hazard ratio of 1.72 (1.38-2.15; p=0.0040) and 1.67 (1.37-2.03; p=0.0037), respectively. INTERPRETATION The death of a child is associated with an overall increased mortality from both natural and unnatural causes in mothers, and an early increased mortality from unnatural causes in fathers.