History of preoperative COVID‐19 infection and postoperative cognitive change among older adults undergoing major elective surgeries

Background Emerging evidence suggests that recovery from COVID‐19 infection may be associated with cognitive decline and possibly, incident dementia. Older adults undergoing major surgeries are at heightened risk for postoperative delirium and delayed cognitive recovery; however, it is unknown whether preoperative COVID‐19 infection is associated with worse perioperative cognitive outcomes. Therefore, the objective of this study was to investigate relationships between history of preoperative COVID‐19 infection and cognitive change following major elective surgery. Method The study population consisted of cognitively normal adults, ≥ 65years, enrolled in the Cognitive Recovery After Elective Surgery (CREATES) study, an ongoing investigation of BBB function and perioperative cognition. Participants who completed preoperative baseline and 2‐month postoperative assessments were included in the analyses. Cognitive performance (global function (MoCA) and age‐ and education‐adjusted letter fluency, category fluency, learning, memory) at baseline was compared with 2‐month postoperative test results in the entire sample and among those with/without preoperative COVID‐19. Between‐group differences were analyzed using independent samples t‐tests, chi‐square analyses, and repeated measures ANOVAs. Result A total of 34 participants (mean age, 75 [SD] 4.9 years; 83% White; 54% orthopedic surgery) were included. Of these, 10 reported a preoperative, non‐hospitalized COVID‐19 infection and 24 did not have preoperative COVID‐19. No cases of postoperative delirium were observed. In the full sample, there was evidence of cognitive improvement in letter fluency (F = 5.53, p = 0.03, η2 = 0.18) and memory (F = 4.42, p = 0.04, η2 = 0.12), relative to preoperative baseline. On the MoCA, a global cognitive measure, 86% scored within normal range (MoCA ≥ 26) 2 months after surgery. COVID sub‐groups did not differ on baseline demographics, family history, medical, or cognitive variables (all p’s