Marked Regional Variation in Acute Stroke Treatment Among Medicare Beneficiaries

Little is known about how regions vary in their use of thrombolysis (intravenous tissue-type plasminogen activator and intra-arterial treatment) for acute stroke. We sought to determine regional variation in thrombolysis treatment and investigate the extent to which regional variation is accounted for by patient demographics, regional factors, and elements of stroke systems of care.

Retrospective cross-sectional study of all fee-for-service Medicare patients with ischemic stroke admitted via the Emergency Department from 2007 to 2010 who were assigned to 1 of 3436 hospital service areas. Multilevel logistic regression was used to estimate regional thrombolysis rates, determine the variation in thrombolysis treatment attributable to the region and estimate thrombolysis treatment rates and disability prevented under varied improvement scenarios.

There were 844 241 ischemic stroke admissions of which 3.7% received intravenous tissue-type plasminogen activator and 0.5% received intra-arterial stroke treatment without or without intravenous tissue-type plasminogen activator over the 4-year period. The unadjusted proportion of patients with ischemic stroke who received thrombolysis varied from 9.3% in the highest treatment quintile compared with 0% in the lowest treatment quintile. Measured demographic and stroke system factors were weakly associated with treatment rates. Region accounted for 7% to 8% of the variation in receipt of thrombolysis treatment. If all regions performed at the level of 75th percentile region, ≈7000 additional patients with ischemic stroke would be treated with thrombolysis.

There is substantial regional variation in thrombolysis treatment. Future studies to determine features of high-performing thrombolysis treatment regions may identify opportunities to improve thrombolysis rates.