Multicomponent non-pharmacological interventions for preventing delirium in critically ill patients: a systematic review and meta-analysis of randomized controlled trials

Background It is necessary to evaluate the efficacy of multicomponent non-pharmacological interventions in preventing and managing intensive care unit (ICU) delirium and identify the most effective intervention combinations. Methods A systematic literature search was conducted in PubMed, EMBASE, CINAHL, Cochrane Library, and ProQuest Dissertations and Theses A&I databases from inception to July 3, 2026, supplemented by a hand search of prior meta-analyses. Only randomized trials were included. Meta-analysis was performed using risk ratios (RR) or mean differences (MD) with 95% confidence intervals (CI). Random-effects models with restricted maximum likelihood estimation and modified Hartung-Knapp confidence intervals were used. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized controlled trials. The certainty of evidence was assessed using the GRADE approach. Results The search identified 13 randomized controlled trials encompassing 5,525 patients. Multicomponent interventions significantly reduced delirium incidence (RR 0.53, 95% CI [0.36, 0.76], I 2 = 72.5%, low-certainty evidence). The effect remained significant after excluding the two cluster-randomized trials (RR 0.45, 95% CI 0.30–0.67; I 2 = 55.7%), the active-control trial (RR 0.55, 95% CI 0.38–0.79; I 2 = 73.0%), and all three trials simultaneously (RR 0.46, 95% CI 0.31–0.70; I 2 = 57.0%). In exploratory subgroup analysis, the within-subgroup pooled estimate for component pattern B, comprising cognitive assessment and stimulation, reorientation, sleep and environmental management, family or community support, and physical activity, showed a reduced incidence of delirium (RR 0.43, 95% CI [0.23, 0.82]); however, the formal test for subgroup differences was not significant ( p = 0.604). No statistically significant effects were found for delirium duration, ICU or hospital length of stay, delirium-free days, or mortality. Conclusion This study demonstrated that multi-component interventions effectively reduce delirium incidence in critically ill patients. The evidence did not establish that one component combination was superior to another. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD42024592821 .