Background and Importance Atrial fibrillation (AF) is a common arrhythmia, affecting nearly half of all geriatric patients. AF poses a significant ischemic stroke risk, making effective anticoagulation essential. Direct oral anticoagulants (DOACs) have emerged as effective stroke-prevention agents, yet underutilisation remains a concern, especially in geriatric patients. To improve pharmacotherapy, including anticoagulation, a clinical pharmacy program was implemented on the geriatric units.

Aim and Objectives On that background, we sought to characterise anticoagulant utilisation patterns and inappropriateness among geriatric AF inpatients.

Material and Methods An observational study was performed at the acute geriatric units of an academic hospital. The first 90 AF patients for 2020, 2021 and 2022, who received at least one oral anticoagulant, were included. Anticoagulant use at discharge and therapy appropriateness were assessed. Determinants for underdosing were evaluated using multivariable logistic regression. Temporal associations for appropriateness (yes or no) and anticoagulant class (Vitamin K antagonist (VKA) vs. DOAC) were assessed using Fisher’s exact analysis.

Results Mean age was 86.5 (±5.3) years with median CHA₂DS₂-VASc score 5 [4–6]. At discharge, 256 (94.8%) patients used a DOAC, 9 (3.3%) used a VKA, 1 (0.4%) a DOAC-antiplatelet combination, and in 4 (1.5%) anticoagulant use was discontinued. Apixaban was most commonly prescribed (40.7%) and a majority of patients (64.4%) received a reduced DOAC dose. Thirty-nine (14.4%) patients received inappropriate therapy and for 23/39 (59.0%) no deviation rationale was documented. The year ‘2022’ (odds ratio 0.104; 95% confidence interval, 0.012–0.878) was the only determinant for underdosing. There was no temporal association regarding appropriateness (P=0.533) or anticoagulant class (P=0.479).

Conclusion and Relevance A majority received anticoagulation at discharge, mostly reduced DOAC doses. Only a minority was managed inappropriately. The reassuring findings over the 3-year period might be explained by the success of the clinical pharmacy programme. In conclusion, on a background of said pharmacy services, most AF patients were treated according to current guidelines. However, deviation from clinical guidelines still occurred consistently, frequently without a documented rationale and largely explained by underdosing in the context of a high bleeding risk. Accordingly, more trial data on the most appropriate anticoagulation strategy are urgently needed in geriatric AF patients with (very) high bleeding risks.

Conflict of Interest No conflict of interest.