Long-term survival of Medicare patients with head injury

An increasing number of older patients are being hospitalized with traumatic brain injury (TBI). Knowledge of their expected long-term survival may be useful in making clinical decisions.

Patients age 65 or older admitted for the first time with head injury (ICD-9 800-804 or 850-854) during 1999 were identified in a complete national sample of fee-for-service Medicare hospitalization and denominator data. Cases were categorized by age, sex, maximum Abbreviated Injury Score (AISmax), and Charlson comorbidity score. Survival was determined at hospital discharge, and (using the denominator file) at 1, 6, 12, and 24 months after the initial hospital admission.

For all cases (n = 30,684), the hospital mortality was 14.3%, but was cumulatively 19.75%, 30.5%, 36.1%, and 44.9% at successive times up to 24 months. Long-term mortality was higher with increased age, comorbidity, or AISmax, and higher in men. These effects persisted with multivariate logistic regression analysis and were used to construct a simplified prediction score for clinical use.

The mortality for older patients with TBI is much higher than for an uninjured control population. The relative risk for death remains elevated after hospital discharge and for at least 2 years. Awareness of the expected prognosis may help family members and health care providers make appropriate clinical decisions during acute hospitalization.