Hypertriglyceridemia is a Major Factor Associated With Elevated Levels of Small Dense LDL Cholesterol in Patients With Metabolic Syndrome

Background: We aimed to determine the major contributing component of metabolic syndrome (MetS) that results in an elevated small dense LDL cholesterol (sdLDL-C) concentration and sdLDL-C/LDL-C ratio. Methods: Four hundred and forty-seven subjects (225 men; 222 women) with MetS were randomly selected from the Korean Metabolic Syndrome Research Initiatives-Seoul cohort study. Age- and sex-matched healthy controls (181 men; 179 women) were also randomly selected from the same cohort. Results: A comparison of the median values of the sdLDL-C concentration between subgroups, divided according to whether subjects met or did not meet the criteria for each MetS component in patients with MetS, revealed a significant difference in the sdLDL-C concentration only between subgroups divided according to whether subjects met or did not meet the triglyceride (TG) criteria (P<0.05 for each gender). The TG level showed a good correlation with sdLDL-C concentration (correlation coefficients [r]=0.543 for men; 0.653 for women) and the sdLDL-C/LDL-C ratio (r=0.789 for men; 0.745 for women). Multiple linear regression analyses conducted for the MetS group concordantly identified TG as one of the most significant contributors to sdLDL-C concentration (0=0.1747 0.0105, P<0.0001) and the sdLDL-C/LDL-C ratio (beta=6.9518 +/- 0.3011, P<0.0001). Conclusions: Among five MetS components, only the abnormal TG level was a differentiating factor for sdLDL-C concentration and sdLDL-C/LDL-C ratio. These results were reproducible in both genders, with or without MetS.