Small-dense LDL Cholesterol is Associated with Insulin Resistance in BMI <30 kg/m², Non-diabetic Japanese Population

Abstract

Aims: Small-dense low-density lipoprotein (sdLDL) and malondialdehyde LDL (MDA-LDL) are considered more atherogenic than LDL. However, information on the major determinants of sdLDL cholesterol (sdLDL-C) and MDA-LDL levels in Japanese subjects without diabetes is limited.

Methods: This study included 870 non-diabetic subjects with a body mass index (BMI) <30 kg/m². All subjects underwent an annual health check-up that included sdLDL-C and MDA-LDL analyses.

Results: When subjects were stratified into four groups according to homeostasis model assessment of insulin resistance (HOMA-IR), sdLDL-C and MDA-LDL levels increased significantly, relative to the reference, with increasing HOMA-IR values, whereas LDL-C levels showed no consistent increase with increasing HOMA-IR. Multiple linear regression and logistic regression analyses revealed that LDL-C and triglyceride (TG) levels were major determinants of sdLDL-C levels, whereas LDL-C, sdLDL-C and high-density lipoprotein cholesterol (HDL-C) levels were major determinants of MDA-LDL levels.

Conclusions: Our data suggest that an increase in the LDL-C level and insulin resistance may lead to an increase in sdLDL-C levels and that increases in the LDL-C and sdLDL-C levels may lead to an increase in MDA-LDL in Japanese subjects without diabetes.