Association of preoperative frailty and delayed neurocognitive recovery in older adults undergoing major elective surgery in Thailand: a single centre prospective study

Background: Delayed neurocognitive recovery (dNCR) is common in older adults and associated with adverse outcomes, but its relationship with frailty remains unclear. We aimed to examine the relationship between preoperative frailty and dNCR, as well as other postoperative outcomes, in older adults undergoing major elective surgery. Methods: This prospective cohort study was conducted at a university hospital and enrolled patients aged 60 years or older who underwent elective surgery under regional or general anesthesia. Frailty was assessed using the Thai version of the FRAIL scale (T-FRAIL). dNCR was defined as a decline of at least 2 points on the Montreal Cognitive Assessment (MoCA) from postoperative day 5-9. The associations between perioperative variables and dNCR were analyzed employing multivariable logistic regression models. Findings: Among the 282 enrolled patients, 204 completed follow-up; 13.5% were identified as frail. dNCR occurred in 26.0% of non-frail and 44.4% of frail patients. Preoperative frailty was associated with an increased risk of dNCR, with an adjusted OR of 2.69, 95% CI 1.08-6.72. Frail patients had longer hospital stays (median 9.5 [7, 16] days vs 8 [6, 12]; p = 0.026), higher in-hospital mortality (7.9% vs 1.2%; p = 0.024), greater total hospitalization costs (median USD 8475 [5504-11,727] vs USD 5950 [3883-8900]; p = 0.005), and higher rate of 3-month readmissions (25.7% vs 12.8%; p = 0.042). At 3 months after surgery, they also had lower functional scores (Barthel Index 81.5 ± 23.7 vs 94.8 ± 10.7; p < 0.001) and lower health utility scores (0.79 ± 2.25 vs 0.91 ± 0.13; p < 0.001). Interpretation: Preoperative frailty was associated with an increased risk of dNCR and poorer postoperative outcomes. Endorsing routine frailty screening, targeted preoperative optimization and multidisciplinary team care perioperatively might be beneficial. Funding: Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand, supported this study (grant number [IO] R016431020).