Association of LDL cholesterol with metabolic syndrome among Iranian adults: a cross-sectional study

Low-density lipoprotein cholesterol (LDL-C) plays a central role in the pathogenesis of cardiovascular disease; however, its association with metabolic syndrome (MetS) and its discriminative ability for identifying individuals with MetS remain unclear. This study aimed to investigate the association between serum LDL-C levels and MetS, as well as its ability to discriminate between participants with and without MetS in men and women. This population-based cross-sectional study included 4,997 adults aged 35–70 years from the Kavar Cohort Study. Participants with major chronic diseases were excluded. Demographic, anthropometric, and biochemical data were collected using standardized protocols. MetS was defined according to ATP III criteria. Logistic regression and ROC curve analyses were used to assess the association and discriminative capacity of LDL-C for MetS. A total of 2,874 apparently healthy participants (1,568 men and 1,306 women) were included. Individuals with MetS showed significantly worse cardiometabolic profiles compared with those without MetS in both sexes (all P < 0.001). LDL-C levels were similar between men with and without MetS, while a slight increase was observed in women with MetS. ROC analysis demonstrated no discriminative ability of LDL-C for identifying MetS in men (AUC = 0.50), while very limited discriminatory ability was observed in women (AUC = 0.54). In logistic regression models, LDL-C was not independently associated with MetS after multivariable adjustment. LDL-C is not independently associated with metabolic syndrome and shows no discriminative ability in men, while it demonstrates very limited discriminatory ability for identifying women with MetS. These findings suggest that LDL-C alone is not a reliable biomarker for MetS in apparently healthy individuals.