Association of systemic inflammation markers in cancer mortality with diabetes: evidence from National Health and Nutrition Examination Survey

Inflammation plays a crucial role in the interconnection between diabetes and cancer. Our study seeks to investigate the predictive value of inflammatory indices concerning overall survival (OS) among diabetic cancer patients. We analyzed data from the National Health and Nutrition Examination Survey between 1999 and 2020. Using four immune-related markers, we employed the log-rank method, multivariate Cox regression, and subgroup analysis to explore the predictive capacity of these markers for OS among adult individuals with diabetes and cancer. Our study identified four systemic immune-inflammatory indices that demonstrated significant predictive potential for OS among diabetic cancer patients, namely systemic immune-inflammation index, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and lymphocyte-to-monocyte ratio (all p values < 0.05). Notably, these inflammatory biomarkers still maintain their predictive value after adjusting potential confounding factors. The analysis using restrictive cubic splines revealed significant non-linear relationships between inflammatory biomarkers and OS. The findings presented in this study underscore the potential of inflammatory markers as prognostic indicators and their crucial role in enhancing risk assessment for diabetic patients with cancer.