Trends in survival after stroke among Medicare beneficiaries

Abstract

Background and purpose: Most strokes occur among people aged 65 years and older. The increasing proportion of persons who are in this age group underlines the importance for health-care providers to be aware of trends in poststroke survival. We investigated poststroke survival trends from 1985 to 1989 among Medicare beneficiaries.

Methods: Medicare hospital claim records and enrollment data were obtained on 1 901 439 Medicare patients with a principal diagnosis of stroke occurring during the years 1985 through 1989. Cox proportional hazard techniques were used to compare the 2-year poststroke survival for strokes occurring in 1986, 1987, 1988, and 1989 relative to strokes occurring in 1985. Poststroke survival trends were examined among groups defined by age, race, region, type of stroke, and, for a 20% subset, history of stroke.

Results: We observed a modest improvement in poststroke survival from 1985 to 1989 (1989:1985 hazard ratio, 0.96; P < .05). Trends for persons with hemorrhagic stroke showed more improvement (hazard ratio, 0.88; P < .05) than those for persons with ischemic stroke (hazard ratio, 0.98; P < .05). Improvement was also greater among persons without known prior hospitalization for stroke (hazard ratio, 0.94; P < .05) and during periods of follow-up shorter than 2 years.

Conclusions: The variations in poststroke survival among subgroups of the population have important implications for the quality of life of stroke survivors and for the future medical and nursing needs of these populations.