Mortality after discharge from acute care hospitalization with traumatic brain injury: a population-based study

Abstract

Ventura T, Harrison-Felix C, Carlson N, DiGuiseppi C, Gabella B, Brown A, DeVivo M, Whiteneck G. Mortality after discharge from acute care hospitalization with traumatic brain injury: a population-based study.

Objective: To characterize mortality after acute hospitalization with traumatic brain injury (TBI) in a socioeconomically diverse population.

Design: Population-based retrospective cohort study.

Setting: Statewide TBI surveillance program.

Participants: Colorado residents with TBI discharged alive from acute hospitalization between 1998 and 2003 (N=18,998).

Interventions: Not applicable.

Main outcome measures: Vital status at the end of the study period (December 31, 2005) and statewide population mortality rates were used to calculate all-cause and cause-specific standardized mortality ratios (SMRs) and life expectancy compared with population mortality rates. The influence of demographics, injury severity, and comorbid conditions on time until death was investigated using age-stratified Cox proportional hazards modeling.

Results: Patients with TBI carried about 2.5 times the risk of death compared with the general population (SMR=2.47; 95% confidence interval [CI], 2.31-2.65). Life expectancy reduction averaged 6 years. SMRs were largest for deaths caused by mental/behavioral (SMR=3.84; 95% CI, 2.67-5.51) and neurologic conditions (SMR=2.79; 95% CI, 2.07-3.77) and were smaller but significantly higher than 1.0 for an array of other causes. Injury severity and older age increased mortality among young people (age <20y). However, risk factors for mortality among adults age 20 and older involved multiple domains of demographics (eg, metropolitan residence), injury-related measures (eg, falls versus vehicular incidents), and comorbidity (eg, > or =3 comorbid health conditions versus none).

Conclusions: TBI confers an increased risk of mortality in the months and years after hospital discharge. Although life expectancy is reduced across the population, the excess in mortality lessens as time since injury increases. Specific risk factors (eg, high injury severity, poor general health) pose an especially high threat to survival and should prompt an increased vigilance of health status, especially among younger patients.