Systematic review and meta-analysis on the incidence of delirium in intensive care unit inpatients after cognitive exercise intervention

Abstract

Background: The incidence of delirium in patients in the intensive care unit (ICU) is relatively high. Current research results on the effect of cognitive exercise on the incidence of delirium in ICU inpatients are inconsistent. In this study, a meta-analysis was performed on the impact of cognitive exercise on the incidence of delirium in ICU inpatients to provide an evidence-based reference for the clinical prevention of delirium.

Methods: Articles were searched in PubMed, MEDLINE, the Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), China Biology Medicine Disc (CBMD), Wanfang Database, and Western Biomedical Journal Database. The search strategy and search terms for Chinese and English databases were as follows: cognitive exercises or activity or functional exercise or rehabilitation or active intervention or gradual training or physical therapy or physical therapy, delirium, and randomized controlled trial (RCT) or randomization. Two researchers were required to independently screen the articles, extract data, and repeatedly assess the risk of bias for the included articles.

Results: A total of 7 studies were included. The incidence of delirium was tested for heterogeneity, which showed that I2=94%>50% and P<0.00001, indicating heterogeneity among studies. There was no significant difference between the treatment group and the routine group [Z=1.28, odds ratio (OR) =0.43, 95% confidential interval (CI): 0.12-1.58, P =0.20]. The duration of delirium in treatment group and routine group was significantly different [Z=3.24, mean difference (MD) =-1.99, 95% CI: -3.20, -0.79, P=0.001]. The heterogeneity test was conducted for the length of hospitalization, showing that Chi-squared test (Chi2) =2.16, degree of freedom (df) =4, I2=0%<50%, and P=0.71, indicating that the heterogeneity of each study group was acceptable. The difference between the treatment group and the routine group was statistically significant (Z=10.84, MD =-2.10, 95% CI: -2.48, -1.72, P<0.00001).

Discussion: Meta-analysis results confirmed that cognitive exercises can reduce the incidence and duration of delirium in ICU inpatients, and shorten the length of hospitalization.

Keywords: Cognitive exercises; delirium; incidence; intensive care unit; meta-analysis.