Lipoprotein subclass profiles in individuals with varying degrees of glucose tolerance: a population-based study of 9399 Finnish men

OBJECTIVES: We investigated serum concentrations of lipoprotein subclass particles and their lipid components determined by proton nuclear magnetic resonance spectroscopy in a population-based study.

DESIGN AND METHODS: A total of 9399 Finnish men were included in the study: 3034 men with normal fasting glucose and normal glucose tolerance; 4345 with isolated impaired fasting glucose (IFG); 312 with isolated impaired glucose tolerance (IGT); 1058 with both IFG and IGT; and 650 with newly diagnosed type 2 diabetes (New DM). Lipoprotein subclasses included chylomicrons (CM) and largest VLDL particles, other VLDL particles (five subclasses), intermediate-density lipoprotein (IDL), LDL (three subclasses) and HDL (four subclasses). The phospholipid, triglyceride (TG), cholesterol, free cholesterol and cholesterol ester levels of the lipoprotein particles were measured.

RESULTS: Abnormal glucose tolerance (especially IGT and New DM) was significantly associated with increased concentrations of VLDL subclass particles and their components (with the exception of very small VLDL particles). After further adjustment for total TGs and HDL cholesterol, increased lipid concentrations in the CM/largest VLDL particles and in most of the other VLDL particles remained significant in individuals with isolated IGT, IFG+IGT and New DM. There was a consistent trend towards a decrease in large and an increase in small HDL particle concentrations in individuals with hyperglycaemia even after adjustment for serum total TGs and HDL cholesterol.

CONCLUSIONS: Abnormal glucose tolerance modifies the concentrations of lipoprotein subclass particles and their lipid components in the circulation and is also related to compositional changes in these particles.