Predictive value of systemic inflammatory indices in metabolic syndrome and non-alcoholic fatty liver disease in Iran.

Abstract

The prevalence of metabolic syndrome has increased significantly, and visceral obesity is closely associated with non-alcoholic fatty liver disease. This study aimed to investigate the association between inflammatory indices derived from blood cell counts and to investigate the association between inflammatory indices, metabolic syndrome, and NAFLD in Sabzevar, Iran, in 2025. This case-control study used data from a large adult cohort. A total of 1500 participants with metabolic syndrome were selected as the case group, and for each case, one control without metabolic syndrome was randomly selected from the same cohort. All participants were subsequently evaluated for the presence or absence of non-alcoholic fatty liver disease and, additionally, for liver fibrosis using the Fibrosis-4 (FIB-4) index. Data were analyzed using SPSS version 16, and a p-value < 0.05 was considered statistically significant. In this study, the mean age was 51.01 ± 8.3 years in the metabolic syndrome group and 46.9 ± 8.2 years in the healthy group. In the metabolic syndrome group, 621 participants were male and 879 were female. Overall, no significant associations were observed between metabolic syndrome and inflammatory indices, including the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammatory response index, hemoglobin level, or liver fibrosis classification based on the Fibrosis-4 (FIB-4) index. In contrast, metabolic syndrome was significantly associated with demographic factors, anthropometric measures, metabolic parameters, non-alcoholic fatty liver disease, and the monocyte-to-high-density lipoprotein cholesterol ratio. Non-alcoholic fatty liver disease showed no significant association with the neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, hemoglobin level, or systemic inflammatory response index. Still, it was significantly associated with demographic characteristics, anthropometric indices, metabolic factors, the platelet-to-lymphocyte ratio, systemic immune-inflammation index. Liver fibrosis classification based on the FIB-4 index was not significantly associated with several metabolic and inflammatory variables; however, it showed significant associations with age, sex, anthropometric measures, selected inflammatory indices, and hemoglobin level. Given that imaging methods are costly and not readily accessible for all patients, the findings of this study may provide a basis for identifying more cost-effective and easily accessible approaches for the diagnosis of this disease.