Abstract
<title>Abstract</title> <p> Postoperative cognitive dysfunction (POCD) commonly occurs within the first postoperative week, but data on its impact on 1-year outcomes remain limited. We aimed to determine the incidence of 1-year mortality among older surgical patients and whether POCD at 1 week is associated with it. We conducted a prospective cohort study at a university hospital, enrolling patients ≥ 60 years undergoing moderate to major surgery. Cognitive function was assessed preoperatively and within 1 week postoperatively using the Montreal Cognitive Assessment, and mortality was evaluated at 1 year. The incidence of 1-year mortality was 5.7% (29/508), and POCD at 1 week, defined as a ≥ 2-point decline from baseline, occurred in 126 patients (24.8%). In multivariable Cox regression, factors independently associated with 1-year mortality were POCD (adjusted hazard ratio [aHR], 2.72; 95% CI, 1.27–5.84; <italic>P</italic> = 0.003), chronic kidney disease stage 4–5 (aHR, 3.11; 95% CI, 1.33–7.27; <italic>P</italic> = 0.009), cancer (aHR, 4.27; 95% CI, 1.97–9.25; <italic>P</italic> < 0.001), and age ≥ 70 years (aHR, 2.66; 95% CI, 1.01–7.04; <italic>P</italic> = 0.049). Early POCD was independently associated with increased 1-year mortality. These findings suggest early identification and prevention of POCD may improve postoperative outcomes and reduce long-term mortality. </p>