Non-pharmacological interventions to prevent and treat delirium in older people: An overview of systematic reviews

Background: As advanced age isa major risk factor for confusion status, delirium has become prevalent in the older population, contributing to longer hospital stays, cognitive impairment, and higher risks of complications and mortality. Compared with pharmacological methods, non-pharmacological interventions are preferred and are recommended by the National Institute for Health and Care Excellence for the prevention of delirium. Numerous systematic reviews and meta-analyses have been carried out to investigate the effects of non-pharmacological interventions. However, the outcomes were diverse and the quality varied widely, making it challenging to draw firm conclusions from the evidence. Objective: To summarize the contents and evaluate the effects of non-pharmacological interventions to prevent and treat delirium among older people. Design: Overview of systematic reviews. Methods: A comprehensive literature search was conducted in Medline, Cochrane Library, EMBASE, CINAHL, PsycINFO, JBI EBP Database, China's SinoMed, CNKI, and Wangfang databases from inception to 2nd December 2022. Two reviewers performed the study selection, quality appraisal, and data extraction independently. The AMSTAR 2 tool was used to appraise the methodological quality of eligible reviews. The results were presented in narrative synthesis based on types of intervention, including multicomponent and single-component interventions. Results: Twenty-four systematic reviews were included in this overview, of which four reviews were of high quality. Multicomponent interventions were the most widely disseminated non-pharmacological strategy, which were effective in preventing delirium with 27 %-54 % reduction in delirium incidence. Additionally, the multicomponent strategy also reduced the incidence of falls and pressure ulcers, and showed trends toward shortening the length of stay and improving cognitive function. Among single-component interventions, physical training, geriatric risk assessment, and reorientation protocol revealed positive effects in delirium prevention. However, the effectiveness of non-pharmacological interventions for treating delirium was limited, and while multicomponent methods had inconsistent impacts on the duration and severity of delirium, single-component methods showed no significant impact. Conclusion: Non-pharmacological interventions are effective in reducing the incidence of delirium and improving other health outcomes among older patients. However, the effects on the duration and severity of delirium need more evidence to confirm. Registration number: CRD42022376651 in PROSPERO. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).