Effect of socioeconomic status on treatment and mortality after stroke

Background and Purpose — Socioeconomic status is associated with increased mortality from ischemic heart disease. We undertook a study to determine whether a similar association exists between socioeconomic status and stroke mortality.

Methods — We linked hospital discharge abstracts and vital-status data for all patients with acute stroke admitted to hospitals in Ontario between April 1994 and March 1997. Socioeconomic status for each patient was inferred on the basis of median neighborhood income. We determined the risk of death at 30 days and 1 year; secondary analyses compared the use of medications, inpatient rehabilitation services, and carotid endarterectomy by socioeconomic status. We used multivariate analyses to adjust for age, sex, stroke type, comorbid conditions, and hospital and physician characteristics.

Results — The study sample consisted of 38 945 patients. Each $10 000 increase in median neighborhood income was associated with a 9% reduction in the hazard of death at 30 days (adjusted hazard ratio 0.91, 95% CI 0.87 to 0.96) and a 5% reduction in the hazard of death at 1 year (adjusted hazard ratio 0.95, 95% CI 0.92 to 0.99). Patients in the lowest income quintile were less likely than those in the highest to receive in-hospital physiotherapy (58% versus 61%, P<0.001), occupational therapy (36% versus 47%, P<0.001), and speech pathology (21% versus 28%, P<0.001). There were no differences in the use of medications or carotid endarterectomy based on socioeconomic status. Waiting times for carotid surgery, however, were significantly longer in the lowest income quintile than the highest (90 days versus 60 days, P=0.002).

Conclusions — Socioeconomic status affects mortality and access to some health services after stroke, even in a country with a universal health insurance program. Understanding and reducing these socioeconomic disparities should be a priority for future research.