Inter-relationship between low-density lipoprotein phenotype and carotid intima-media thickness in North Indian type 2 diabetic subjects

AimsDiabetic dyslipidemia is characterized by a preponderance of small dense LDL which is highly atherogenic. The aim of this study was to examine the interrelationship between LDL Phenotype and atherosclerosis; to determine the factors determining LDL phenotype; and evaluate LDLc:apo-B ratio as a surrogate for the assessment of LDL phenotype in a group of North Indian Type 2 diabetic subjects.Methods285 diabetic subjects attending the outpatient Endocrine Clinic were subjected to detailed anthropometry and fasting serum lipid and apo-B was measured. The carotid intima-media thickness (IMT) was determined using a high resolution B-mode Ultrasonography. LDLc:apo-B ratio was taken as a surrogate index for LDL size.Results29.5% patients with normal triglyceride levels and 52.1% patients with normal LDLc levels showed the presence of small dense LDL or Phenotype B as estimated by the LDL cholesterol/apo-B ratio. The mean IMT in Phenotype B group was higher (0.88 mm vs. 0.68 mm). Triglycerides was the most important predictor variable predicting carotid IMT (R2 = 0.15, β = 0.376) as well as LDL phenotype B (R2 = 0.28, β = 0.561).ConclusionsTriglycerides and HDLc contribute independently to the variability in LDL particle size, and LDL particle size was associated with preclinical atherosclerosis as determined by carotid IMT in North Indian Type 2 diabetic subjects. LDL cholesterol/apo-B ratio serves as an easy clinical tool to determine the elevated small dense LDL.