The Relationship Between Small Dense Low-Density Lipoprotein Cholesterol and Metabolic Syndrome

Background: Prior research has established an association between small dense low-density lipoprotein cholesterol (sdLDL-C) and dyslipidemia, serving as a significant marker for predicting cardiovascular diseases. Nevertheless, the connection between sdLDL-C and metabolic syndrome (MetS) remains unclear. Methods: This study retrospectively analyzed 23,187 individuals who underwent health checkups at Taizhou Hospital's health management center. Here, we investigated the relationship between sdLDL-C and MetS, along with its components, utilizing Spearman correlation analysis, receiver operating characteristic (ROC) curve analysis, logistic regression, and mediation analysis. Results: The MetS group exhibited significantly higher level of sdLDL-C compared to the non-MetS group (P<0.001). We observed a strong correlation between sdLDL-C and several key factors: TG (r = 0.711), TC (r = 0.672), LDL-C (r = 0.781), GGT (r = 0.420), and HDL-C (r = -0.417). After adjusting for age and gender, the odds ratio (OR) (95% confidence interval [CI]) for MetS incidence in the second, third, and fourth quartiles versus the first quartile of sdLDL-C concentration were 2.264 (95% CI: 1.851, 2.770), 4.053 (95% CI: 3.350, 4.903), and 9.034 (95% CI: 7.531, 10.837). The optimal cut-off value for diagnosing MetS using sdLDL-C was determined to be 0.98 mmol/L, with an area under the ROC curve (AUC) of 0.716 (95% CI: 0.705, 0.726). Additionally, mediation analysis revealed that sdLDL-C mediated a 12.8% correlation between GGT and TG concentration. Conclusion: The sdLDL-C is correlated with MetS and it can successfully mediate the relationship between GGT and TG. Our data suggests that sdLDL-c and GGT are suitable parameters for preventing and monitoring MetS.