Abstract 15979: Change in Body Mass Index is a Major Determinant of Lifestyle Induced Changes in Lipoprotein Particle Size and Number in the Diabetes Prevention Program (DPP)
Insulin resistant states are characterized by increased large VLDL, small LDL and small HDL particles (p) which may contribute to atherosclerosis risk. We have previously shown that lifestyle (ILS) intervention used to prevent diabetes in subjects with impaired glucose tolerance also lowered VLDL size (VLDLz) and increased LDL size (LDLz) and HDL size (HDLz) reflecting a shift from small to large LDLp and HDLp as measured by NMR technology (see table for abbreviations). To understand the basis for these changes we explored the role of changes in body mass index (BMI), insulin resistance (HOMA-IR), fasting glucose (FG), physical activity (met hrs/wk), dietary saturated fat (g/24 hr) and adiponectin (APN immunoturbidimetry) in explaining the ILS induced effects on lipoprotein particles using regression models among the subset of ILS and placebo participants with measurements at baseline and after 1 year of intervention (n=1034). FG, physical activity, and saturated fat were not correlated with lipoprotein size or number at baseline. BMI and HOMA-IR correlated positively with VLDLz and L-VLDLp but inversely with LDLz and HDLz; S-LDLp and S-HDLp were also positively and L-LDLp and L-HDLp inversely correlated (all p<0.001). APN had the same but reciprocal correlations as BMI and HOMA-IR. The estimates (β) of the ILS effect from the regression models are summarized in the table. In Model 1, ILS significantly reduced L-VLDLp, S-LDLp and S-HDLp and increased L-HDLp compared to placebo albeit with modest R2. Among the 3 covariates examined, the ILS effect was mediated mostly through the ΔBMI (model series 3). The ILS effect was fully explained for L-VLDLp and was attenuated for S-LDLp, S-HDLp and L-HDLp as seen in the change in R2 and the significance of the estimate from Model 1. Our findings highlight the significant role of the ILS associated change in BMI for both diabetes prevention and favorable lipoprotein changes that may contribute to atherosclerosis prevention.
- © 2011 by American Heart Association, Inc.