Abstract
OBJECTIVES: To assess the relationship of acute complications, preexisting chronic diseases, and substance abuse with clinical and functional outcomes among adults 50 years and older with moderate-to-severe traumatic brain injury (TBI). DESIGN: Prospective cohort study. PARTICIPANTS: Adults 50 years and older with moderate-to-severe TBI (n = 2134). MEASURES: Clusters of comorbid health conditions empirically derived from non-injury International Classification of Diseases, Ninth Revision codes, demographic/injury variables, and outcome (acute and rehabilitation length of stay [LOS], Functional Independence Measure efficiency, posttraumatic amnesia [PTA] duration, institutionalization, rehospitalization, and Glasgow Outcome Scale-Extended (GOS-E) at 1 year). RESULTS: Individuals with greater acute hospital complication burden were more often middle-aged men, injured in motor vehicle accidents, and had longer LOS and PTA. These same individuals experienced higher rates of 1-year rehospitalization and greater odds of unfavorable GOS-E scores at 1 year. Those with greater chronic disease burden were more likely to be rehospitalized at 1 year. Individuals with more substance abuse burden were most often younger (eg, middle adulthood), black race, less educated, injured via motor vehicle accidents, and had an increased risk for institutionalization. CONCLUSION: Preexisting health conditions and acute complications contribute to TBI outcomes. This work provides a foundation to explore effects of comorbidity prevention and management on TBI recovery in older adults.