Associations of inflammation-related nutritional and metabolic status indices CAR and CTI with 90-day unfavorable functional outcomes in patients with acute ischemic stroke.

Background: Composite indices integrating inflammation, nutritional reserve, and metabolic status may improve early prognostic assessment after acute ischemic stroke (AIS). This study examined the associations of the C-reactive protein-to-albumin ratio (CAR) and the CRP-triglyceride-glucose index (CTI) with 90-day functional outcomes. Methods: A Korean single-center stroke registry (2010-2016) was analyzed ( Results: Unfavorable outcomes occurred in 414 patients (27.9%). After full adjustment, higher CAR (OR 1.25, 95% CI 1.09-1.43) and higher CTI (OR 1.38, 95% CI 1.19-1.60) were independently associated with unfavorable outcome. CTI showed an approximately linear risk gradient, whereas CAR showed evidence of a non-linear association. As single predictors, CAR and CTI yielded AUCs of 0.656 and 0.651 and outperformed albumin, triglycerides, and fasting plasma glucose. A six-variable model including sex, age, body mass index, admission NIHSS, CAR, and CTI achieved an apparent AUC of 0.837. Internal validation showed stable performance, with a mean cross-validated AUC of 0.831, mean Brier score of 0.142, calibration intercept of 0.023, and calibration slope of 1.018. Conclusion: CAR and CTI, derived from routine admission laboratory tests, were associated with 90-day functional outcomes after acute ischemic stroke and may aid early prognostic assessment. The derived six-variable model showed acceptable internal performance, but should be considered exploratory pending external validation.