Objective:
Regionalization of stroke care has occurred sporadically across the U.S, so determining realistic goal treatment rates for individual regions or the nation as a whole is challenging. Studies of a single hospital or region vary widely in estimates of eligibility for acute therapy and may have limited generalizability or biases. We hypothesized that the proportion of U.S. Medicare beneficiaries receiving acute stroke therapy varies by region. Treatment rates in high performing regions may represent realistic national goals and inform policy to increase treatment rates.
Methods:
All Medicare beneficiaries with a principal diagnosis of ischemic stroke (ICD-9 433.x1, 434.x1, 436) admitted through the emergency department were identified using MEDPAR files from 2007-2010. Receipt of IV tPA (DRG 559, MS-DRG 61-63, ICD-9 procedure code 99.10) or IA thrombolysis (CPT code 37184-6, 37201, 75896 via linked Medicare Carrier files) was determined. Patients were assigned to one of 3,436 Hospital Service Areas (HSA; local health care markets for hospital care) by zip code. Regional acute stroke treatment rates were calculated and the lowest and highest quintiles were compared. Multi-level logistic regression was used to adjust for individual demographics as well as regional population density, education, median income, and unemployment using linked census data. Model-based adjusted regional acute stroke treatment rates were estimated.
Results:
Of 916,232 stroke admissions 3.6% received IV tPA only and 0.6% received IA or combined therapy. Unadjusted treatment rates by region ranged from 0.8% (minimum) to 14.8% (maximum). Regional rates ranged from 1.7% (quintile 1) to 5.4% (quintile 5). Regions with higher education, population density and income had higher treatment rates (p <= 0.001). After adjustment, regional differences were attenuated slightly _ 1.9% (quintile 1) to 5.1% (quintile 5).
Conclusions:
Marked variation exists in acute stroke treatment rates by region, even after adjusting for patient and regional characteristics, supporting the perception that a major opportunity exists to improve acute stroke treatment within many HSAs.
A step toward understanding the mechanism of action of audit and feedback: a qualitative study of implementation strategies
