Exploring the interplay between systemic immune-inflammatory response, nutritional patterns, and metabolic health in...

Metabolic dysfunction-associated fatty liver disease (MAFLD) represents a highly prevalent liver disorder characterized by hepatic fat accumulation in the context of metabolic impairment. Persistent low-grade inflammation is recognized as a central mechanism underlying its development and progression. The Systemic Immune-Inflammation Index (SII), derived from circulating neutrophil, lymphocyte, and platelet counts, has emerged as a composite indicator of inflammatory and immune status. Nevertheless, limited evidence exists regarding its association with dietary quality and cardiometabolic features in individuals with MAFLD. This aim of this study was to investigate the relationship between SII levels, metabolic parameters and adherence to a Mediterranean-style dietary pattern in adults diagnosed with MAFLD. In this cross-sectional study, a total of 254 adults with confirmed MAFLD were enrolled in this cross-sectional analysis. Participants were stratified into tertiles according to SII values. Anthropometric measurements, biochemical parameters, and dietary data were obtained for all subjects. Habitual food consumption was evaluated using a validated food frequency questionnaire, and diet quality was quantified through the Mediterranean Dietary Quality Index (MED-DQI). Between-group differences were assessed using one-way analysis of variance and Chi-square tests. Partial correlation analysis was used to assess the association between SII, MED-DQI and metabolic variables adjusted for the confounders. Also, multivariable general linear models were applied to control for potential confounding variables. Participants within the highest SII tertile demonstrated significantly higher serum triglyceride concentrations (T3: 197.42 ± 108.83 mg/dL vs. T1: 147.55 ± 87.77 mg/dL; P < 0.05) and markedly lower HDL-C levels compared with those in lower tertiles (T1: 51.94 ± 13.34 mg/dL vs. T3: 45.28 ± 11.08 mg/dL; P < 0.001). Although overall MED-DQI scores were not significantly different between SII tertiles, poorer scores in the fruits and vegetables component were observed among individuals with elevated SII. A positive correlation was found between SII and neutrophil counts (r = 0.438), platelet counts (r = 0.309) and a negative correlation with lymphocyte counts (r = -0.466) and HDL cholesterol (r = -0.238; for all of them P < 0.001). Triglyceride levels was also positively correlated with SII (r = 0.214, P = 0.001). A significant positive correlation was observed between MED-DQI and lymphocyte counts (r = 0.215) and HDL (r = 0.158, P < 0.001 and P < 0.05 respectively). Higher systemic immune-inflammatory burden is associated with higher TG and lower HDL and lower dietary fruits and vegetables score in patients with MAFLD. These findings highlight a potential link between inflammatory activation, dietary inadequacy, and metabolic disturbances. Due to cross-sectional design of the current study, casualty cannot be directly inferred and prospective investigations are warranted to clarify the causal direction of these associations.