Dose-dependent effects of perioperative opioids on cognitive outcomes in older adults undergoing laparoscopic cholecystectomy and hernia repair: A prospective observational study

Background: Opioids are essential for perioperative analgesia, yet their impact on postoperative cognitive dysfunction remains unclear. Evidence is limited in older adults undergoing laparoscopic cholecystectomy and hernia repair. We sought to evaluate the association between perioperative opioid dose, expressed as morphine milligram equivalents, and postoperative cognitive dysfunction, assessed using Addenbrooke's Cognitive Examination-III at 24 hours and 30 days. Methods: This prospective observational study enrolled patients >60 years undergoing elective laparoscopic surgery (80 cholecystectomies and 20 hernia repairs) from March 2023 and January 2024. Patients with pre-existing cognitive impairment, open conversion, or early discharge were excluded. Total perioperative opioid dose (morphine milligram equivalents/kg) was the primary predictor, and postoperative cognitive dysfunction (Addenbrooke's Cognitive Examination—III decline at 24 h and 30 days) was the outcome. Analysis included t tests, Fisher exact test, Pearson correlation, and multivariable regression with subgroup comparison. Results: Of 102 patients, 100 were analyzed (80 cholecystectomy, 20 hernia repair; mean age 67.8 ± 6.3 years). Postoperative cognitive dysfunction occurred in 36% at 24 hours and 12% at 30 days. Incidence was 35% versus 40% at 24 hours and 13.8% versus 5% at 30 days for cholecystectomy and hernia, respectively. Greater opioid doses correlated with lower Addenbrooke's Cognitive Examination—III scores (r = —0.6439, P < .0001). Multivariable analysis showed increased odds of early postoperative cognitive dysfunction with greater opioid use (odds ratio, 1.59; 95% confidence interval, 1.30—1.96, P < .0001), whereas greater body mass index and male gender were protective. Conclusions: Greater opioid doses were significantly associated with early postoperative cognitive dysfunction, whereas greater body mass index and male gender appeared protective. Larger studies are needed to confirm these findings.