Mortality and morbidity 15 years after hospital admission with mild head injury: a prospective case-controlled population study

Objective To investigate mortality rate in a population of adults admitted to hospital with mild head injury (MHI) 15 years later. Design A prospective case control, record linkage study. Participants 2428 adults with MHI and an equal number of community controls (CC) were case-matched for age, gender and social deprivation. A further control group admitted with a non-head injury was in addition matched for duration of hospital admission. Controls with a history of head injury prior to study entry were excluded. Main outcome measures Death or survival 15 years poststudy entry. Results Mortality per 1000 per year after MHI (24.49; 95% CI 23.21 to 25.79) was higher than in CC (13.34; 95% CI 12.29 to 14.44; p