Effects of Physical Exercise on the Incidence of Delirium and Cognitive Function in Acutely Hospitalized Older Adults: A Systematic Review with Meta-Analysis

Background: Acute care hospitalization increases the likelihood of developing cognitive impairment and delirium in older adults. Objective: To summarize evidence about the effectiveness of exercise and physical rehabilitation interventions on the incidence of delirium and cognitive impairment in acutely hospitalized older patients. Methods: Relevant articles were systematically searched (PubMed, Web of Science, and CINHAL databases) until 26 August 2021. Randomized and nonrandomized controlled trials of in-hospital physical exercise interventions and rehabilitation programs compared to usual care performed for older patients (> 65 years) hospitalized for an acute medical condition were selected. The primary endpoints were changes in the incidence of delirium and cognition during acute hospitalization. The secondary endpoints included functional independence, psychological measures, well-being status, length of hospital stay, transfer after discharge, fall occurrence, hospital readmissions, and mortality rate. The endpoints were evaluated at different time points (at admission, at discharge, and after discharge). Results: Eleven studies from 8 trials (n = 3,646) were included. The methodological quality of the studies was mostly high. None of the studies reported any adverse events related to the intervention. Early rehabilitation improved cognitive function at 3 months postdischarge (Hedge's g = 0.33, 95% confidence interval [CI] 0.19 to 0.46, p < 0.001). No between-group differences were found for incident delirium and cognitive impairment during hospitalization (all p > 0.05). Conclusion: In-hospital physical exercise and early rehabilitation programs seem to be safe and effective interventions for enhancing cognitive function after discharge in older patients hospitalized for an acute medical condition. However, no potential benefits were obtained over usual hospital care for the incidence of delirium.