Non-HDL cholesterol and apolipoprotein B in the dyslipidemic classification of type 2 diabetic patients

Abstract

Objective: To compare non-HDL cholesterol (HDLc) and apolipoprotein B (apoB) in the identification of nonconventional high-risk dyslipidemic phenotypes in type 2 diabetic patients.

Research design and methods: Total cholesterol and triglycerides, HDLc, LDL cholesterol, non-HDLc, apolipoprotein B (apoB), and LDL size were determined in 122 type 2 diabetic patients (68% male, aged 59.6 +/- 9.7 years, and HbA(1c) 7.5% [range 5.2-16.0]). They were then classified as normo- and hypertriglyceridemic if their triglyceride concentrations were below/above 2.25 mmol/l, as normo/hyper-non-HDLc if non-HDLc concentrations were below/above 4.13 mmol/l, and as normo- and hyperapoB if apoB concentrations were below/above 0.97 g/l. Both classifications were compared (concordance assessed with the kappa index), and low HDLc and LDL phenotype B were identified in each category.

Results: A total of 26 patients were hypertriglyceridemic and 96 were normotriglyceridemic. All hypertriglyceridemic subjects had increased non-HDLc, whereas 24 had increased apoB (kappa= 0.95). In the normotriglyceridemic group, 44 had increased non-HDLc, 68 had increased apoB, and 25 of the 52 patients with normal non-HDLc had increased apoB (kappa= 0.587). Low HDLc and LDL phenotype B were similarly distributed into the equivalent categories.

Conclusions: Non-HDLc and apoB are equivalent risk markers in hypertriglyceridemic patients, but apoB identifies additional patients with high-risk dyslipidemic phenotypes in normotriglyceridemic type 2 diabetic patients.