System inflammation response index: a novel inflammatory indicator to predict all-cause and cardiovascular disease mortality in the obese population

Abstract Aim This study aims to investigate the relationship between two novel inflammatory markers, namely, the Systemic Inflammatory Response Index (SIRI) and the Systemic Immune Inflammatory Index (SII), as well as the all-cause and cardiovascular disease (CVD) mortality in the obese population. Materials and methods We conducted a prospective cohort study based on the data of 13,026 obese adults (age ≥ 18 years) from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014 and followed until December 2019. SIRI was calculated by the formula: (neutrophil count × monocyte count) / lymphocyte count, while that of SII was: (platelet count × neutrophil count)/lymphocyte count. The association of SIRI and SII with all-cause and CVD mortality was evaluated using Cox regression. In addition, the nomogram was performed to predict 10-year survival probability. Results During a median follow-up of 137 months, 1959 and 553 all-cause and CVD deaths were recorded, respectively. Spearman correlation analysis indicated that SIRI and SII were unrelated to almost all baseline characteristics (r