Background: This systematic review was conducted to evaluate any interventions to prevent incident delirium, or shorten the duration of prevalent delirium, in older adults presenting to the emergency department (ED). Methods: Health sciences librarian designed electronic searches were conducted from database inception through September 2021. Two authors reviewed studies, and included studies that evaluated interventions for the prevention and/or treatment of delirium and excluded non-ED studies. The risk of bias (ROB) was evaluated by the Cochrane ROB tool or the Newcastle-Ottawa (NOS) scale. Meta-analysis was conducted to estimate a pooled effect of multifactorial programs on delirium prevention.Results: Our search strategy yielded 11,900 studies of which 10 met study inclusion criteria. Two RCTs evaluated pharmacologic interventions for delirium prevention; three non-RCTs employed a multi-factorial delirium prevention program; three non-RCTs evaluated regional anesthesia for hip fractures; and one study evaluated the use of Foley catheter, medication exposure, and risk of delirium. Only four studies demonstrated a significant impact on delirium incidence or duration of delirium-one RCT of melatonin reduced the incidence of delirium (OR 0.19, 95% CI 0.06 to 0.62), one non-RCT study on a multi-factorial program decreased inpatient delirium prevalence (41% to 19%) and the other reduced incident delirium (RR 0.37, 95% CI 0.22 to 0.61). One case-control study on the use of ED Foley catheters in the ED increased the duration of delirium (proportional OR 3.1, 95% CI 1.3 to 7.4). A pooled odds ratio for three multifactorial programs on delirium prevention was 0.46 (95% CI 0.31-0.68, I 2 = 0).
Conclusion:Few interventions initiated in the ED were found to consistently reduce the incidence or duration of delirium. Delirium prevention and