Frequency of thrombolytic therapy in patients with acute ischemic stroke and the risk of in-hospital mortality: the German Stroke Registers Study Group

Abstract

Background and purpose: There is little information about early outcome after intravenous application of tissue-type plasminogen activator (tPA) for stroke patients treated in community-based settings. We investigated the association between tPA therapy and in-hospital mortality in a pooled analysis of German stroke registers.

Methods: Ischemic stroke patients admitted to hospitals cooperating within the German Stroke Registers Study Group (ADSR) between January 1, 2000, and December 31, 2000, were analyzed. The ADSR is a network of regional stroke registers, combining data from 104 academic and community hospitals throughout Germany. Patients treated with tPA were matched to patients not receiving tPA on the basis of propensity scores and were analyzed with conditional logistic regression. Analyses were stratified for hospital experience with the administration of tPA.

Results: A total of 13,440 ischemic stroke patients were included. Of these, 384 patients (3%) were treated with tPA. In-hospital mortality was significantly higher for patients treated with tPA compared with patients not receiving tPA (11.7% versus 4.5%, respectively; P<0.0001). After matching for propensity score, overall risk of inpatient death was still increased for patients treated with tPA (odds ratio [OR], 1.7; 95% CI, 1.0 to 2.8). Patients receiving tPA in hospitals that administered <or=5 thrombolytic therapies in 2000 had an increased risk of in-hospital mortality (OR, 3.3; 95% CI, 1.1 to 9.9). No significant influence of tPA use for risk of inpatient death was found in hospitals administering >5 thrombolytic treatments per year (OR, 1.3; 95% CI, 0.8 to 2.4).

Conclusions: In-hospital mortality of ischemic stroke patients after tPA use varied between hospitals with different experience in tPA treatment in routine clinical practice. Our study suggested that thrombolytic therapy in hospitals with limited experience in its application increase the risk of in-hospital mortality.