Elderly patients, especially elderly women, with atrial fibrillation (AF) have low rates of anticoagulation, according to a retrospective study by Vibhuti Singh, MD.

Despite the existence of clear guidelines that recommend use of anticoagulant therapy for reducing the risk of stroke in individuals with AF, anticoagulation rates have been historically low for women, particularly elderly women, who are at especially high risk of stroke, he said.

As part of the study, records from 347 patients with paroxysmal and persistent AF were reviewed. One-hundred thirty-one of the patients were women, of whom 79 were age ≥ 70.

Of the 131 women, only 62% were on warfarin, compared with 76% of the 216 men. Only 49% of the subgroup of women age ≥ 70 were chronically anticoagulated, compared with 80% of their younger counterparts (P < 0.05). The rate of warfarin use among the elderly women was also lower than that in the 113 elderly men (61%; P <0.05).

"Various reasons were given for the nonuse of warfarin in the elderly women," said Dr. Singh, clinical assistant professor, University of South Florida, St. Petersburg. These were physician deferral due to advanced age (37%), minor bleeds and bruises (20%), falls or gait issues (15%), patient's choice (17%), major bleeding (6%), and other reasons including problems in obtaining laboratory tests (5%).

"It is surprising that actual bleeding is not the commonest reason for such deferral," said Dr. Singh. "Rather, physicians or patient's choice (or fear) seem to be the most important factors. Addressing these correctable factors can potentially lead to a dramatic reduction in the risk of stroke in the elderly women."