Determinants of Post-Operative Cognitive Decline in Elderly People

Abstract

Background: Surgery and anesthesia can result in temporary or permanent deterioration of the cognitive functions, for which causes remain unclear. Objectives: In this pilot study, we analyzed the determinants of cognitive decline following a non-emergency elective prosthesis implantation surgery for hip or knee. Design: Prospective single-center study investigating psychomotor response time and changes in MoCA scores between the day before (D-1) and 2 days after (D+2) following surgery at the Lariboisière Hospital (Paris, France). Participants: 60 patients (71.9±7.1-year-old, 72% women) were included. Measurements: Collected data consisted in sociodemographic data, treatments, comorbidities and the type of anesthesia (local, general or both). Furthermore, we evaluated pain and well-being before as well as after the surgery using point scales. Results: Post-operative (D+2) MoCA scores were significantly lower than pre-operative ones (D-1) with a median difference of 2 pts [IQR]=4pts, (p<0.001), we found no significant difference between locoregional and general anesthesia. Pre-operative benzodiazepine or anticholinergic treatments were also associated to a drop in MoCA scores (p=0.006). Finally, the use of ketamine during anesthesia (p=0.043) and the well-being (p=0.006) evaluated before intervention, were both linked to a reduced cognitive impact. Conclusion: In this pilot study, we observed a post-operative short-term cognitive decline following a lower limb surgery. We also identified pre and perioperative independent factors linked to cognitive decline following surgery. In a next stage, a larger cohort should be used to confirm the impact of these factors on cognitive decline.