Frailty and anticoagulant prescription in older hospitalized patients with atrial fibrillation: a multi-centred observational study

Abstract Background Evidence of the impact of frailty on anticoagulant prescription in older people with atrial fibrillation (AF) is conflicting. Some studies suggested that oral anticoagulants (OACs) were underutilized in older people with frailty while others have not found this. Aims The primary aim of this study was to examine the prevalence of frailty in hospitalized older patients with AF and the association between frailty and OAC prescription during admission. The secondary aim was to examine the association between frailty and prescription of rate/rhythm control medications during admission. Methods This is a retrospective observational cohort study. Adults aged ≥65 years with AF admitted to six hospitals in Australia between 1 June 2022 and 31 August 2022 were eligible for this study. Frailty was defined by a Frailty Index constructed using information from the electronic medical records. Logistic regression models were applied to examine the association between frailty and the prescriptions of OACs, rate control drugs and rhythm control drugs during admission. Results are presented as odds ratios and 95% confidence intervals. Results A total of 685 patients were included in this analysis. They had a mean age of 82.6, and 49.8% were female. Using the cut-off point of 0.25, 42.8% of the patients were identified as being frail. Overall, 75.6% of the patients were prescribed OACs (67.9% in the frail compared to 81.4% in the non-frail, p<0.001), 37.7% received rate control drugs (42.0% in the frail versus 34.4% in the non-frail, p=0.044), while 27.3% received rhythm control drugs (22.9% in the frail compared to 30.6% in the non-frail, p=0.024). The adjusted odds ratios of frailty on prescriptions during admission were 0.53 (95%CI 0.37 – 0.78) for OACs, 1.45 (95%CI 1.05 – 1.99) for rate control drugs, and 0.79 (95%CI 0.55 – 1.13) for rhythm control drugs. Conclusion Our study found a high prevalence of frailty in older inpatients with AF and frailty was associated with a reduced likelihood of receiving OACs. Further studies are needed to understand the reasons for under-coagulation in frail patients with AF.Prescriptions of OACs during admission