Effectiveness and safety of thromboprophylaxis with enoxaparin in medical inpatients

Abstract Background Venous thromboembolism (VTE) includes deep vein thrombosis and pulmonary embolism. Although effective prophylaxis exists for medical patients, there is little information outside of clinical trials. We will analyze our experience in the prophylaxis of VTE with enoxaparin in hospitalized medical patients. Material and methods We studied all of the patients ≥ 15 years admitted for emergency care to all of the medical department s of the hospital, except for the Hematology Department, between 1/April/1999 and 31/December/2005. The patients’ age, sex, Charlson comorbidity index (CCI), whether they received prophylaxis with enoxaparin or not, dose, VTE, bleeding, thrombocytopenia, and mortality were analyzed. Results 40,349 patients were included, of which 55.87% were male, with an average age of 67.56, and an average CCI of 4.99. There were 19,834 patients who did not receive prophylaxis for which the rate of incidence of VTE was 0.61%, mortality 8.75%, bleeding 1.38%, and thrombocytopenia 0.04%. Prophylactic enoxaparin was administered to 20,515 patients, for which the rate of incidence of VTE was 0.44%, mortality 10.71%, bleeding 1.1%, and thrombocytopenia 0.04%. The adjusted Odds Ratio (OR) for VTE was 0.65 (95% confidence interval [95% CI] 0.49 to 0.87). The adjusted OR for mortality was 0.84 (95% CI 0.78 to 0.9). With the adjusted data, the number needed to treat (NNT) for VTE was 470.3 (95% CI 278.4 to 1413.3), and the NNT for mortality was 77.2 (95% CI 54.6 to 130.3). Conclusion Thromboprophylaxis with enoxaparin in hospitalized medical patients is associated with a lower incidence of VTE and mortality, and is safe.