Biomarkers in Obesity-Related Metabolic Syndrome: Relationships Between LDL Subfractions, Lipid Profile, and...

Background: Metabolic syndrome (MetS) is associated with increased cardiometabolic risk, although substantial metabolic abnormalities may also occur in individuals with normal body weight. This study compared anthropometric characteristics, body composition, lipid profile, LDL subfractions, inflammatory markers, liver biomarkers, and novel cardiometabolic indices in participants with MetS according to obesity status and characterized the metabolic phenotype of normal-weight participants with MetS. Methods: This cross-sectional study included 188 Slovak adults. Anthropometric, biochemical, lipoprotein, inflammatory, liver function, and cardiometabolic parameters were assessed. Group differences were analyzed using the Mann-Whitney U test, and associations were evaluated by Spearman's correlation analysis. Results: Compared with controls, participants with MetS had significantly greater adiposity, visceral fat accumulation, atherogenic lipid alterations, elevated inflammatory and liver biomarkers, higher blood pressure, and increased cardiometabolic indices (p < 0.05). Within the MetS group, overweight/obese participants exhibited greater visceral adiposity and higher liver enzyme concentrations, whereas most lipid parameters, LDL subfraction distribution, and several cardiometabolic indices were comparable between weight groups. VAI, TyG, TyG-BMI, TyG-WC, TyG-WHtR, LAP, AIP, and CMI showed strong correlations with visceral adiposity, triglycerides, atherogenic LDL subfractions, and smaller LDL particle size. Conclusions: Obesity worsens body composition and hepatic dysfunction in MetS but has limited impact on several metabolic and atherogenic characteristics. LDL-C concentration alone may not sufficiently reflect the true atherogenic risk. These findings support the metabolically unhealthy normal-weight phenotype and highlight the value of novel cardiometabolic indices and LDL subfraction analysis for improved cardiometabolic risk assessment.