Pre-diabetes in overweight youth and early atherogenic risk

Abstract

PurposeTo compare atherogenic lipoprotein particles and vascular smooth muscle biomarkers in overweight youth with pre-diabetes (PD) vs. normal glucose tolerance (NGT). Methods144 adolescents (60 black, 84 white; 102 female; PD=45, NGT=99) aged 10–19years underwent a fasting blood draw and 2-h OGTT. Lipoprotein particle size and subclass concentration and vascular smooth muscle biomarkers (ICAM-1, VCAM-1 and E-selectin) were compared between youth with PD and NGT. ResultsCompared with NGT, PD adolescents had smaller LDL (mean±SE: 20.5±0.1 vs. 21.0±0.1nm; P=0.002) and HDL (8.62±0.05 vs. 8.85±0.04nm; P=0.013) size and elevated medium small (159.2±10.3 vs. 123.8±6.4nmol/L; P=0.037) and very small (626.3±45.4 vs. 458.5±26.4nmol/L; P=0.032) LDL particle concentrations, after adjustment for race and BMI. Further adjusting for fasting insulin or visceral adiposity obviated these differences between the groups except for LDL size. ICAM-1 and E-selectin did not differ in youth with PD but correlated with LDL and HDL size, and small LDL particle concentrations. ConclusionsOverweight adolescents with PD have an atherogenic lipoprotein profile of small LDL and HDL size and increased concentrations of small LDL, moderated by insulin resistance and visceral adiposity, but independently driven by dysglycemia for LDL size. Associations between smooth muscle biomarkers and lipoproteins could be an early signal heralding the atherogenic process. It remains to be determined if correction of dysglycemia and associated lipoprotein abnormalities in obese youth could prove effective in halting this process.