Association between Cognitive Impairment Severity and Polypharmacy in Older Patients with Atrial Fibrillation: A Retrospective Study Using Inpatient Data from a Specialised Geriatric Hospital.

This study aimed to investigate the association between cognitive impairment and polypharmacy in patients with atrial fibrillation prone to cognitive decline, and to elucidate if the Dementia Assessment Sheet for Community-based Integrated Care System 21-Items (DASC-21) severity classification indicates drug adjustment. This retrospective cohort study used the DASC-21 and Diagnosis Procedure Combination data at a specialised geriatric hospital with patients hospitalised between April 2019 and March 2022. The association between cognitive severity evaluated using the DASC-21 and polypharmacy was investigated using a multivariate logistic regression model. Data of 1191 inpatients (44.3% aged ≥85 years, 49.0% male) were analysed. Compared with severe cognitive impairment, mild (odds ratio [OR]: 3.33, 95% confidence interval [CI]: 1.29-8.57) and moderate (OR: 2.46, 95% CI: 1.06-5.72) impairments were associated with concurrent use of ≥6 medications. Antithrombotics were related to polypharmacy. The ORs did not change with 6, 8, or 10 medications (2.11 [95% CI: 1.51-2.95, p < 0.001], 2.42 [95% CI: 1.79-3.27, p < 0.001], and 2.01 [95% CI: 1.46-2.77, p < 0.001], respectively). DASC-21 severity was associated with polypharmacy in patients with atrial fibrillation, with a trend toward decreased polypharmacy from moderate to severe. The DASC-21 may serve as an indicator for drug adjustment in clinical practice.