Effects of oral anticoagulant therapy in older medical in-patients with atrial fibrillation: a prospective cohort observational study.

Background: Uncertainties about efficacy and safety of oral anticoagulant therapy (OAT) among older and frail medical patients with atrial fibrillation (AF) largely contribute to under-prescription of these drugs.

Aims: In this prospective observational cohort study, we investigated mortality, and ischemic and hemorrhagic events, in hospital-discharged older patients with AF.

Methods: Stroke and bleeding risk were evaluated using CHA2DS2-VASC and HAS-BLED scores. Comorbidity, frailty, cognitive and nutritional status and functional autonomy were evaluated using standardized scales. Independent associations between clinical variables, including OAT use, and all-cause mortality, fatal and non-fatal ischemic and hemorrhagic events, were evaluated. Further clinical outcomes comparison between patients treated with OAT and those untreated was performed after adjustment for significant differences in patient baseline characteristics with propensity score matching.

Results: Of 452 patients included (mean age 81.6 years, 54.9 % women, roughly 30 % cognitively impaired and/or functionally dependent, mean CHA2DS2-VASC and HAS-BLED scores 4.6 and 2.8, respectively), 151 (33.4 %) died during a mean follow-up period of 300.5 days; ischemic and hemorrhagic stroke occurred in 4.0 and 0.4 % of patients, respectively, and major bleedings in 6.2 %.

Discussion: After multivariate analysis, OAT at discharge was associated with lower overall mortality and reduced occurrence of ischemic stroke, the first finding being confirmed in propensity score matched analysis.

Conclusions: Among older vulnerable AF patients with high post discharge death rate, OAT was associated, among other multiple factors, with reduced mortality and lower occurrence of ischemic stroke.