Activity of daily living upon admission is an independent predictor of in-hospital mortality in older patients with community-acquired pneumonia

BACKGROUND: Older patients hospitalized with community-acquired pneumonia (CAP) are at high risk for short-term mortality. Activity of daily living (ADL) is associated with clinical outcomes in older patients. We aimed to investigate the prognostic value of ADL upon admission on the in-hospital mortality in older patients with CAP. METHODS: We conducted a retrospective cohort study involving patients aged ≥65 years admitted to Beijing Chao-Yang hospital due to CAP between June 2012 and June 2020. ADL evaluation upon admission was performed by Barthel Index (BI). Data from all patients were extracted from the electronic medical records. RESULTS: Four thousand eight hundred eighty patients were included, 131 patients (2.7%) died during their hospitalization. Median BI in the Deceased group was 45 (20–65), Deceased group had lower BI scores than Survivors group (p < 0.001). Low BI (< 60) was more frequent in patients who died in the hospital than in patients discharged alive (69.5% vs. 13%, p < 0.001). In-hospital mortality was higher among patients with worse ADL upon admission (BI< 60) compared to those BI≥60 (12.6% vs. 0.9%). The worse ADL upon admission (BI< 60) was associated with an increase in the risk of death during CAP hospitalization, worse ADL upon admission (BI< 60) showed an odds ratio (OR) for in-hospital mortality of 7.53 (95%CI: 2.77–20.48; P < 0.01). This association remained significant after adjustment for age, comorbid conditions, respiratory failure, pathogens and laboratory findings (OR, 3.74; 95%CI, 2.37–5.91; P < 0.01). Receiver operating characteristic (ROC) curve revealed that BI upon admission is a predictor related to in-hospital mortality in elderly patients, the area under the ROC curve of BI in predicting in-hospital mortality was 0.81 (with 95% confidence interval: 0.78–0.85). The predictive value of ADL upon admission was better than age in our study population. CONCLUSION: Activity of daily living upon admission is an independent predictor of in-hospital mortality in older patients with community-acquired pneumonia. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12879-021-06006-w.