Prognostic value of the inflammatory index in predicting cardiovascular and all-cause mortality in diabetic patients: a systematic review and meta-analysis

Introduction Diabetes mellitus (DM) is a widespread chronic disease associated with a high risk of cardiovascular complications. Identifying reliable Score for predicting cardiovascular and overall mortality in diabetic patients is crucial for early intervention. Purpose This study aims to evaluate the prognostic significance of the systemic immune-inflammation index (SII), calculated from platelet, neutrophil, and lymphocyte counts, as a novel strategy for risk assessment in diabetic individuals. Methods We performed a systematic review and meta-analysis, searching PubMed, Embase, and Cochrane databases to identify studies examining the relationship between SII and mortality in patients with DM. We followed PRISMA reporting guidelines. Eligible studies were analysed using a random-effects model, pooled as hazard ratio (RR), and heterogeneity was assessed using the I² statistic. We used Review Manager 4.1 for statistical analysis. Results A total of 31,841 diabetic patients from five studies were included in the analysis. Higher levels of SII were significantly associated with an increased risk of both cardiovascular and overall mortality in patients with DM. The HR for overall mortality was 1.27, with all the values adjusted for potential confounders (95% CI 1.01–1.59; p=0.04; Figure 1A). Similarly, there was also an association between higher SII and CV mortality, with a HR of 1.50 (95% CI: 1.05–2.16; p=0.03; Figure 1B). Conclusion This systematic review and meta-analysis identified the SII as an important marker for overall mortality and cardiovascular mortality in patients with diabetes. Additional studies are warranted to evaluate the independent prognostic value of SII in this population.