C-reactive protein-triglyceride-glucose index predicts postoperative delirium in older surgical patients: a retrospective cohort study

Postoperative delirium (POD) is a prevalent and serious complication in older surgical patients. The C-reactive protein-triglyceride-glucose index (CTI) is a recently developed composite marker that integrates both Insulin resistance (IR) and systemic inflammation. This study aimed to evaluate the association between CTI and POD in older surgical patients. Older surgical patients were retrospectively enrolled. The CTI was calculated and analyzed as both a continuous variable and a binary variable dichotomized at the optimal cut-off derived from receiver operating characteristic (ROC) analysis. Univariate and multivariable logistic regression models were constructed to examine the association between CTI and POD. Joint stratification by the TyG index and CRP was performed to delineate the synergistic contributions of IR and inflammation. A total of 10,125 patients were included in the final analysis. The receiver operating characteristic (ROC) curve analysis determined the optimal cut-off value for CTI to be 7.57. As a binary variable, high CTI conferred significantly elevated odds of POD compared with low CTI in fully adjusted model (OR = 1.60, 95% CI: 1.28-2.00, P < 0.001). As a continuous variable, each unit increment in CTI was associated with a 35% increased risk of POD after full adjustment (OR = 1.38, 95% CI: 1.21–1.56, P < 0.001). Joint stratification further confirmed that patients with concurrently high TyG and high CRP exhibited the highest POD incidence. CTI may be a useful adjunct for preoperative risk stratification of POD in older surgical patients, but requires prospective validation.