BACKGROUND: Mortality in patients after carotid artery stenting (CAS), a treatment approach for atherosclerotic carotid artery stenosis, is influenced by numerous factors. This study aimed to investigate the prognostic value of the Naples prognostic score (NPS), which reflects nutritional and inflammatory status, in CAS patients. METHODS: We retrospectively included 697 patients who underwent CAS from January 2016 to December 2020 at our institute. The primary endpoint of the study was long-term all-cause mortality. The study population was divided into two groups based on the NPS value: Low NPS (NPS 0-2) and high NPS (NPS 3-4). Univariable and multivariable Cox regression analysis was used to identify independent predictors of death. RESULTS: The median follow-up time was 60.8 (46.36-75.36) months. During the follow-up period, all-cause mortality was higher in the high-NPS group compared to the low-NPS group [54% (n = 88) vs. 24% (n = 128) p <
0.001]. Advanced age (p = 0.003), diabetes (p = 0.023), and NPS (hazard ratio: 1.83, confidence interval: 1.58-2.12, p <
0.001) were found to be independent predictors of all-cause mortality at long-term follow-up. CONCLUSION: Consequently, NPS as a marker of malnutrition and inflammation, was found to be associated with long-term mortality and serves as an independent predictor of long-term mortality in patients undergoing CAS.