Characterizing preoperative domain-specific performance on the Montreal Cognitive Assessment and exploring its associations with adverse outcomes

Abstract Purpose The Montreal Cognitive Assessment (MoCA) is a validated screening tool for cognitive impairment (CI) in surgical populations that assesses multiple cognitive domains. The primary objective of this report was to characterize preoperative domain-specific performance on the MoCA in older surgical patients. The secondary objectives were to explore preoperative characteristics and adverse outcomes associated with poorer domain-specific performance. Methods This was a post hoc analysis of the Detection of Cognitive Impairment (Detect CI) study. The MoCA was administered preoperatively to assess seven cognitive domains: executive/visuospatial function, naming, attention, language, abstraction, delayed recall, and orientation. It was scored out of 30, with higher education-adjusted MoCA scores indicating better cognitive performance and scores $$\le$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>≤</mml:mo> </mml:math> 25 classifying probable CI. Adverse outcomes were collected in 382 participants at 30 days and 379 participants at 90 days postoperatively. Results The 382 participants (median age, 73 years [IQR, 68, 77]; 58% female) had a mean MoCA score of 25.9 $$\pm$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>±</mml:mo> </mml:math> 2.8, with 35% screening positive for CI. Participants with probable CI performed significantly poorer across all seven cognitive domains (executive/visuospatial function, naming, attention, language, abstraction, delayed recall, and orientation) than those without CI. Having $$\le$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>≤</mml:mo> </mml:math> 12 years of education was associated with poorer executive/visuospatial function, naming, language, abstraction, and delayed recall. Of all cognitive domains, exploratory analyses showed that only orientation was associated with 30-day adverse outcomes after adjusting for age, sex, education level, and/or American Society of Anesthesiologists status and within-domain multiplicity. Each one-point decrease in orientation score was associated with a longer length of stay (β = 0.5, 95% confidence interval [95% CI] 0.2–0.8; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.012) and higher adjusted odds of postoperative delirium (adjusted odds ratio [aOR] = 11.4, 95% CI 2.6–46.8; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.004), complications (aOR = 3.1, 95% CI 1.3–8.9; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.035), non-home discharge (aOR = 4.1, 95% CI 1.5–11.4; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.014), and composite adverse outcomes (aOR = 5.6, 95% CI 1.9–23.9; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.014). Orientation remained associated with postoperative delirium after adjusting for multiplicity both within and across MoCA domains (aOR = 11.4, 95% CI 2.6–46.8; P $$=$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> 0.031). Conclusions This analysis characterized preoperative domain-specific performance on the MoCA in older adults, with participants screening positive for CI exhibiting poorer performance across all cognitive domains. Exploratory findings suggested that orientation difficulties may be associated with early adverse outcomes, with postoperative delirium showing the most robust association.