OBJECTIVE: To prospectively study the frequency of complications in patients treated with warfarin followed at Botucatu Medical School. METHODS: Patients randomly selected among those with appointments scheduled from June 2002 to February 2004. At the first appointment, a protocol was filled with identification and clinical data. At every return or when the patient went to the hospital due to clinical events, another form was filled with the international normalized ratio, existence and type of clinical event and the conditions of use of vitamin K antagonists. RESULTS: A total of 136 patients (61 men and 75 women), were followed; 99 patients with venous thromboembolism and 37 with arterial disease; 59 were from Botucatu and 77 were from other municipalities. Thirty clinical events were registered: nine of them were not related to the use of warfarin and 21 were hemorrhagic complications (38.8 per 100 patients-year). One hematemesis was considered severe (1.9 per 100 patients-year). The others were considered moderate or mild. There were no deaths, intracranial hemorrhage or cutaneous necrosis. The only significant association was frequency of hemorrhage and average international normalized ratio level. CONCLUSION: Our results demonstrate the feasibility of this treatment in vascular patients in our country, even in socially and economically poor populations, when treated in specialized clinics.
Anticoagulants; warfarin; adverse effects; vascular diseases; venous thrombosis; pulmonary embolism
