Role of Small Dense Low-density Lipoprotein Cholesterol in Cardiovascular Events in Patients with Coronary Artery Disease and Type 2 Diabetes Mellitus Receiving Statin Treatment

Aim: There is little information on the relationships of serum small dense low-density lipoprotein cholesterol (sdLDL-C) levels and serum triglyceride (TG) levels with cardiovascular events in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (DM) who are receiving statins. The aim of this study was to evaluate the relationships of serum TG levels and sdLDL-C levels as residual risks for cardiovascular events in patients with CAD and type 2 DM who were being treated with statins.Methods: The subjects were divided into four groups based on TG levels and sdLDL-C levels: sdLDL-C of <40.0 mg/dL and TG of <150 mg/dL, sdLDL-C of >= 40.0 mg/dL and TG of <150 mg/dL, sdLDL-C of <40.0 mg/ dL and TG of >= 150 mg/dL, and sdLDL-C of >= 40.0 mg/dL and TG of >= 150 mg/dL. During a median follow-up period of 1419 days, cardiovascular events occurred in 34 patients.Results: The incidences of cardiovascular events were significantly higher in patients with sdLDL-C of >= 40.0 mg/dL and TG of <150 mg/dL and in patients with sdLDL-C of >= 40.0 mg/dL and TG of >= 150 mg/dL, but not in patients with sdLDL-C of <40.0 mg/dL and TG of >= 150 mg/dL, than in patients with sdLDL-C of <40.0 mg/dL and TG of <150 mg/dL.Conclusions: Under the condition of treatment with statins, patients with CAD and type 2 DM who had sdLDL-C levels of >= 40.0 mg/dL had a high risk for cardiovascular events even though serum TG levels were controlled at <150 mg/dL.