Hemorrhagic incidents during prolonged ambulatory treatment with acenocoumarol

BACKGROUND: To analyze hemorrhagic complications in a series of outpatients treated with acenocoumarol in an anticoagulant specialized unit by a prospective observational clinical study. PATIENTS AND METHODS: 1,200 outpatients (682 women/518 men, mean age 54.6 +/- 15.8 yrs.) treated with acenocoumarol for at least 6 weeks, with a total follow-up of 2,795 patients-yr. Prevalence and incidence of bleeding was analyzed. The episodes that were potentially life-threatening, or forced to blood transfusion or hospital patient admittance were considered as major bleedings, and the remainder episodes were minor. RESULTS: There were 379 minor bleedings in 258 patients (incidence 13.56/100 patients-yr.), 45 major bleedings (1.61/100 patients-yr.) and 2 lethal bleedings (0.07/100 patients-yr.). Minor bleedings correlated with more advanced age (57.3 +/- 11.8 vs. 53.9 +/- 16.7 yrs., p = 0.002), with the first two months in treatment in the 511 patients who start the treatment during the study (31.09 vs. 13.04/100 patients-yr., p < 0.001), and with a worse achievement of the desired anticoagulation (72.4% vs. 81.6%; p = 0.002). Major bleeding was associated with local causes in 48.9%, and with an excessive anticoagulation in 35.6%. CONCLUSIONS: Bleeding is relatively frequent during acenocoumarol therapy, mainly in patients with worse control, but only in a few of these episodes is severe, and is usually associated with local lesions.