Childhood adversities and accident mortality in early adulthood - a population-based cohort study

Childhood adversities are common and linked to increased risk of premature mortality, including deaths from accidents in early adulthood. We examined associations between childhood adversity and specific types of lethal accidents using nationwide register data from 1,282,636 individuals in the DANish LIFE course (DANLIFE) cohort born between Jan 1, 1980, and Dec 31, 2001, who did not die or emigrate before age 16. Individuals were classified into five trajectory groups based on annual exposure to 12 adversities across three dimensions from ages 0-15. Accident mortality was categorised into traffic, narcotic and hallucinogenic, other poisoning, and other accidents. Individuals were followed through Dec 31, 2022. Relative and absolute risks were estimated using Cox proportional hazards and Aalen additive hazard models. Compared with the low-adversity group, individuals in one of the childhood adversity groups experienced 4.4 to 33.8 additional accident deaths per 100,000 person-years. The largest relative (HR=13.4 95% CI [9.9-18.6]) and absolute (HD=12.9 95%CI [10.0-15.8]) differences were identified for the high versus low adversity group. High childhood adversity is strongly associated with preventable accident mortality in early adulthood, underscoring the need for structural and social interventions to reduce adversity exposure and related excess mortality.