Determinants of Post-Operative Cognitive Decline in Elderly People

Surgery and anesthesia can result in temporary or permanent deterioration of the cognitive functions, for which causes remain unclear.

In this pilot study, we analyzed the determinants of cognitive decline following a non-emergency elective prosthesis implantation surgery for hip or knee.

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).

60 patients (71.9±7.1-year-old, 72% women) were included.

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.

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.

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.