Thrombolytic Therapy and Mortality in Patients With Acute Pulmonary Embolism—Invited Commentary

Background: In the management of acute pulmonary embolism, the prevalence of thrombolytic therapy is uncertain, and its benefits compared with standard anticoagulation remain a subject of debate. Methods: This analysis included 15 116 patient discharges with a primary diagnosis of pulmonary embolism from 186 acute care hospitals in Pennsylvania (January 2000 to November 2002). We compared propensity score-adjusted mortality between patients who received thrombolysis and those who did not, using logistic regression to model mortality within 30 days of presentation and Poisson regression to model in-hospital mortality. Results: Of the 15 116 patient discharges, only 356 (2.4%) received thrombolytic therapy. The overall 30-day mortality rate for patients who received thrombolytic therapy was 17.4% compared with 8.6% for those who did not. The corresponding in-hospital mortality rates were 19.6 and 8.3, respectively, per 1000 person-days. However, mortality risk associated with thrombolysis varied with the propensity to receive thrombolysis: the odds ratios of 30-day mortality were 2.8 (P=.007), 3.9 (P<.001), 1.8 (P=.09), 1.0 (P=.98), and 0.7 (P=.30) for patients in the lowest to the highest quintiles of the propensity score distribution who received thrombolysis. A similar pattern was observed in the risk ratios for in-hospital death. Conclusions: In this large sample of patients hospitalized for acute pulmonary embolism, thrombolytic therapy was used infrequently. Risk of in-hospital and 30-day mortality appears to be elevated for patients who were unlikely candidates for this therapy based on characteristics at presentation, but not for patients with a relatively high predicted probability of receiving thrombolysis.