Abstract 44: Do the Addition of Non-Label Inclusion and Exclusion Criteria for tPA Impact U.S. Treatment Rates?

Background: U.S. IV tPA treatment rates are lower than many countries, despite more than 800 certified Stroke Centers. We sought to understand if Stroke Centers utilized expanded inclusion/exclusion criteria beyond the Activase® label, and how use of these impacts treatment rates. Methods: U.S. Stroke Centers were invited to participate in a survey consisting of a checklist of tPA inclusions/exclusions derived from the Activase® label and stroke center websites. Data were entered and analyzed in SPSS using descriptives, Student t-test, Pearson’s correlation, and binary logistic regression. Results: 229 responses were received from 43 states and the District of Columbia; 31% were academic medical centers, 69% were community hospitals, 92% were PSC certified. Annual ischemic strokes averaged 374+261 (median 300), with 31+41 (median 20) IV tPA cases, for an overall tPA treatment rate of 8.7% + 6.4 (median 7%). Academic hospital tPA treatment rate was significantly higher (10.8 + 7.7; median 8%; t=2.3; mean difference 2.75; p=.026, 95% CI .33-5.2) than community hospitals (8+5.9; median 6%); 24% limited treatment to 3 hours. Additional criteria beyond the Activase® label (Table 1) were reported by 81%, the most common additional inclusions were “total NIHSS > 4 points” and “occlusion on CTA;” the most common additional exclusion was “rapid improvement despite remaining disabling deficit.” As the number of non-standard inclusions/exclusions increased, the tPA treatment rate decreased (r = -.153; p=.038). Using binary logistic regression, utilization of non-standard inclusions/exclusions was predicted by hospital type, admission volume, and use of the 3 hour window (p<.0001). Conclusions: Custom inclusion/exclusion criteria are common and likely contribute to national treatment rates. Certifying bodies should consider requiring adherence to Activase®-label defined criteria as a method to improve tPA treatment rates.