Association Between Barthel Index and Delirium During Hospitalization in Older Patients with Acute Decompensated Heart Failure

Background: Although delirium is an acute confusional state, the available literature identifies impaired activities of daily living (ADL) as a predisposing factor. However, the question of whether ADL is associated with delirium in older patients with heart failure (HF) has not been evaluated. This study investigated the relationship between ADL and delirium and further explored whether HF phenotype moderates the relationship in older patients with acute decompensated HF (ADHF). Methods: In older patients with ADHF, stabilized after HF admission, handgrip strength (HGS) and 6 min walk distance (6MWD) tests were performed, and ADL was assessed using the Barthel index. Delirium during hospitalization was defined according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Logistic regression analyses were used to estimate the association of physical activity and ADL with delirium during hospitalization in older patients with ADHF. Results: A total of 245 older patients (82.9 ± 6.0 years, 49.4% male) with ADHF (heart failure with preserved ejection fraction [HFpEF]; n = 107, 44%) were analyzed. In the group with delirium (n = 65, 26.5%), there was significant difference in Mini–Mental state examination (MMSE) score (19 vs. 25, p < 0.001), HGS (13 vs. 16 kg, p < 0.05), 6MWD (120 vs. 160 m, p < 0.05) and Barthel index (55 vs. 65, p < 0.05) compared to the group without delirium. In the HFpEF group, 6MWD (p < 0.05) and Barthel index (p < 0.001) had significant negative correlations with delirium. In the multiple logistic regression analysis adjusted for the confounders, Barthel index (Odds ratio: 0.390 per 1 standard deviation, p < 0.01) was significantly associated with delirium in the HFpEF group. Conclusions: In older ADHF patients, decreased physical activity and ADL were significantly correlated with delirium. Lower Barthel index was associated with delirium, and this association was significantly modified by HFpEF status.