Head injury is associated with significant morbidity and mortality. Long‐term associations of head injury with dementia in community‐based populations are less clear.
Prospective cohort study of 14,376 participants (mean age 54 years at baseline, ...
Head injury is associated with significant morbidity and mortality. Long‐term associations of head injury with dementia in community‐based populations are less clear.
Prospective cohort study of 14,376 participants (mean age 54 years at baseline, 56% female, 27% Black, 24% with head injury) enrolled in the Atherosclerosis Risk in Communities (ARIC) Study. Head injury was defined using self‐report and International Classification of Diseases, Ninth/Tenth Revision (ICD‐9/10) codes. Dementia was defined using cognitive assessments, informant interviews, and ICD‐9/10 and death certificate codes.
Head injury was associated with risk of dementia (hazard ratio [HR] = 1.44, 95% confidence interval [CI] = 1.3‐1.57), with evidence of dose‐response (1 head injury: HR = 1.25, 95% CI = 1.13‐1.39, 2+ head injuries: HR = 2.14, 95% CI = 1.86‐2.46). There was evidence for stronger associations among female participants (HR = 1.69, 95% CI = 1.51‐1.90) versus male participants (HR = 1.15, 95% CI = 1.00‐1.32), P‐for‐interaction < .001, and among White participants (HR = 1.55, 95% CI = 1.40‐1.72) versus Black participants (HR = 1.22, 95% CI = 1.02‐1.45), P‐for‐interaction = .008.
In this community‐based cohort with 25‐year follow‐up, head injury was associated with increased dementia risk in a dose‐dependent manner, with stronger associations among female participants and White participants.