Life expectancy following rehabilitation: A NIDRR traumatic brain injury model systems study

OBJECTIVE: To characterize overall and cause-specific mortality and life expectancy among persons who have completed inpatient traumatic brain injury rehabilitation and to assess risk factors for mortality. DESIGN: Prospective cohort study. SETTING: The Traumatic Brain Injury Model Systems. PARTICIPANTS: A total of 8573 individuals injured between 1988 and 2009, with survival status per December 31, 2009, determined. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Standardized mortality ratio (SMR), life expectancy, cause of death. RESULTS: SMR was 2.25 overall and was significantly elevated for all age groups, both sexes, all race/ethnic groups (except Native Americans), and all injury severity groups. SMR decreased as survival time increased but remained elevated even after 10 years postinjury. SMR was elevated for all cause-of-death categories but especially so for seizures, aspiration pneumonia, sepsis, accidental poisonings, and falls. Life expectancy was shortened an average of 6.7 years. Multivariate Cox regression showed age at injury, sex, race/ethnic group, marital status and employment status at the time of injury year of injury, preinjury drug use, days unconscious, functional independence and disability on rehabilitation discharge, and comorbid spinal cord injury to be independent risk factors for death. CONCLUSION: There is an increased risk of death after moderate or severe traumatic brain injury. Risk factors and causes of death have been identified that may be amenable to intervention.