A study of elderly adults taking warfarin admitted with prolonged international normalized ratio: a community hospital's experience.

Objectives: To assess bleeding complications and outcome of individuals receiving oral anticoagulants who were admitted to the hospital with an international normalized ratio (INR) greater than 4 by comparing them according to age (≤ 80, >80).

Design: Retrospective cohort study.

Setting: Community hospital.

Participants: All individuals (N = 253) admitted to the Department of Internal Medicine over a period of 4 years with an INR greater than 4: Group I, aged 80 and younger (n = 127); Group II, older than 80 (n = 126). Data included bleeding complications, survival, and quality of INR control before admission and up to 48 months after admission.

Results: Atrial fibrillation was the most common indication for warfarin therapy. Its incidence was higher in the older group (88% vs 73%, P = .004). More elderly participants lived in nursing homes (23% vs 9.4%. P = .004) or received in-home assistance (38.9% vs 20.5%, P = .002). There was no difference in INR upon admission, duration of warfarin treatment, or frequency of INR tests before admission. The incidence of bleeding events was 18.1% in Group I and 12.7% in Group II (P = .30). Major bleeding events occurred in 1.6% of Group I and none of Group II (P = .50). During follow-up after the first admission, the incidence of INR greater than 4 was higher in Group II (87.3% vs 70%, P = .02), without a difference in the number of additional admissions or bleeding events.

Conclusion: Primary care physicians can safely maintain warfarin treatment in elderly adults, even in those with a history of hospitalization for high INR, using frequent INR measurements.