IMPORTANT CONTRIBUTION OF LIPOPROTEIN PARTICLE NUMBER TO PLASMA TRIGLYCERIDE CONCENTRATION IN TYPE-2 DIABETES

The aim of the present study was to determine the contributions of par ticle size versus number to differences in plasma triglyceride-rich li poprotein concentrations in patients with type 2 diabetes. Fasting pla sma was obtained from 174 consecutive eligible men and women with type 2 diabetes (with or without insulin treatment, mean age 57.0 + 6.3 ye ars) who were undergoing coronary angiography. The triglyceride-rich ( Sf 12-400) lipoproteins (TRL) were subfractionated into the Sf 12-60 a nd Sf 60-400 subfractions. Particle numbers, estimated by measuring ap olipoprotein B by electroimmunoassay, in each of these lipoprotein fra ctions were related to enzymatically determined triglyceride levels in the triglyceride-rich lipoproteins. Approximately 87% of the triglyce ride-rich lipoprotein particles were in the Sf 12-60 fraction and 13% in the Sf 60-400 fraction. Multiple linear regression indicated that 6 9% (i.e. r(2) = 0.69) of the variance in the triglyceride levels could by explained by differences in TRL particle number and 17% (i.e. r(2) = 0.17) by the differences in particle triglyceride content. These ob servations are similar in each gender and in those with or without ins ulin treatment. In conclusion, in type 2 diabetes, the vast majority o f triglyceride-rich lipoproteins are smaller particles which are in th e Sf 12-60 fraction. Differences in particle number, rather than trigl yceride content, account for approximately 70% of the differences in t riglyceride levels observed between individuals. Previous demonstratio ns, in those without diabetes, of an association between small triglyc eride-rich lipoproteins with coronary artery disease suggest the impor tance of these findings to the increased atherosclerosis in diabetes. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.