Trends in hospitalization associated with traumatic brain injury.

CONTEXT: Traumatic brain injury (TBI) is associated with more than 50000 deaths in the United States each year, and recent observations suggest a substantial decline in TBI-related hospitalizations and deaths.

OBJECTIVE: To analyze long-term trends in TBI-related hospitalization in the United States.

DESIGN, SETTING, AND PARTICIPANTS: Analysis of existing data from 1980 through 1995 from the National Hospital Discharge Survey, an annual survey representing the US general population. The number of participating hospitals ranged from 400 to 494.

MAIN OUTCOME MEASURES: Annual rates of TBI-related hospitalization, stratified by age, sex, severity of injury, and outcome.

RESULTS: The annual number of TBI cases identified from the sample during the study period ranged from 1611 to 3129. Overall rates of hospitalization for TBI declined an estimated 51%, from 199 to 98 per 100000 per year. When analyzed by severity of injury, mild TBIs declined most during this period, from 130 to 51 hospitalizations per 100000 per year (61% decline; P<.001 compared with intermediate and severe TBI). The decline was greatest among those aged 5-14 years (-66%) and least among those aged 65 years or older (-9%). The ratio of male to female rates showed little variation during the study period (ratio, 1.8; 95% confidence interval [CI], 1.6-2.0), as did the in-hospital mortality rate (mean, 5.3 per 100000; 95% CI, 3.6-7.1).

CONCLUSIONS: Changes in hospital practices may be a major factor in the declining rates of TBI-related hospital admissions. These practices increasingly appear to exclude persons with less severe TBI from hospital admission and shift their care to outpatient settings.