Effect of electroacupuncture on postoperative delirium in older patients undergoing major surgery: a prospective, multicenter, randomized sham-controlled trial

Abstract Purpose Postoperative delirium (POD) is a common complication in older patients undergoing major surgery and is associated with prolonged hospitalization, delayed recovery, and increased mortality. This study evaluated whether perioperative electroacupuncture (EA) reduces the incidence of POD in older surgical patients. Methods This multicenter, participant- and outcome assessor-blinded, randomized, sham-controlled trial included 878 patients aged 65–90 years who underwent major surgery at eight hospitals in China between September 2018 and October 2022. Participants were randomly assigned in a 1:1 ratio to receive EA or sham electroacupuncture (SEA). The EA group received stimulation at Baihui, Yintang, bilateral Shenmen and bilateral Neiguan acupoints using alternating frequencies of 2 and 100 Hz, beginning 30 min before induction of anesthesia and continuing until the end of surgery. The SEA group received sham needling at nonacupoints approximately 20 mm from the corresponding acupoints, without electrical stimulation. The primary outcome was the incidence of POD during postoperative days 1–5. Secondary outcomes included postoperative pain, subjective sleep quality, lengths of intensive care unit and hospital stay, cognitive function and quality of life at 30 days, and adverse events. Results POD occurred in 53 of 439 patients (12.1%) in the EA group and 77 of 439 patients (17.5%) in the SEA group. In the primary unadjusted between-group analysis, EA was associated with a lower incidence of POD than SEA, with an absolute risk difference of −5.5 percentage points (95% CI, −10.2 to −0.8), a relative risk of 0.69 (95% CI, 0.50–0.95), and an odds ratio of 0.65 (95% CI, 0.44–0.94; P = 0.023 ). Analyses adjusted for baseline covariates and study center, as well as the available-case analysis, produced similar estimates. However, the estimated effect was attenuated when all indeterminate outcomes were classified as POD and was no longer evident under an extreme worst-case assumption for the EA group. After adjustment for multiple comparisons, no significant between-group differences were observed in intensive care unit or hospital length of stay, postoperative Acute Physiology and Chronic Health Evaluation II scores, modified Telephone Interview for Cognitive Status scores, or World Health Organization Quality of Life–BREF scores. In repeated-measures analyses, the EA group had slightly lower pain scores at 2 h and on postoperative days 1 and 2 and lower subjective sleep scores on the day of surgery and the first postoperative morning. Adverse events were infrequent and occurred at similar frequencies in the two groups. Conclusions Among older patients undergoing major surgery, the EA group had a modestly lower incidence of POD than the SEA group, without an increase in adverse events. However, the result was sensitive to the handling of indeterminate POD assessments. The observed differences in postoperative pain and subjective sleep quality were small and should be regarded as secondary findings. Further studies are warranted to confirm the effect of EA on POD prevention; the present findings do not establish broader benefits for postoperative recovery. Trial registration ClinicalTrials.gov identifier NCT03606941; prospectively registered on July 31, 2018. Principal investigator: Jianbo Yu.