From clinical trials to clinical practice: oral anticoagulation among patients with non-rheumatic, atrial fibrillation.

OBJECTIVES

The aim of the present study was to evaluate the impact of the results of clinical trials on the prophylactic treatment of non-rheumatic atrial fibrillation with oral anticoagulants.

METHODS

Retrospectively, we studied a random sample of 375 patients discharged from our hospital with a diagnosis of non-rheumatic atrial fibrillation between 1991 and 1993. Information about diagnoses, other clinical variables and treatments prescribed at discharge was obtained from the hospital medical records.

RESULTS

During the whole study period, 14% of patients were prescribed an oral anticoagulant agent and 17% were prescribed acetylsalicylic acid. A non-significant increase in the proportion of patients prescribed oral anticoagulant drugs, from 9% to 17%, was observed. Multivariate analysis showed that a history of stroke (OR = 5.96) and younger age were significantly associated with the prescription of oral anticoagulants. ASA prescription was strongly associated with a history of concomitant vascular disease (OR = 5.8), but not with other risk factors for stroke. Sixty-five percent of patients had one or more risk factors for stroke, did not present any contraindications to anticoagulant agents, but nevertheless were not prescribed one of these drugs.

CONCLUSIONS

Anticoagulant agents and acetylsalicylic acid were largely underprescribed to patients with non-rheumatic atrial fibrillation, and oral anticoagulants were not prescribed according to the individual patients' risk of stroke.