Apolipoprotein L-I is positively associated with hyperglycemia and plasma triglycerides in CAD patients with low HDL

Apolipoprotein L-I (apoL-I) is present on a subset of HDL particles and is positively correlated with plasma triglycerides (TGs). We measured plasma apoL-I levels in coronary artery disease ( CAD) subjects with low HDL who were enrolled in an angiographic CAD prevention trial. At baseline, apoL- I levels ( n = 136; range, 2.2 - 64.1 mug/ml) were right skewed with a large degree of variability. Multivariate analysis for biological determinants of apoL- I revealed that the log of VLDL-TG ( + 0.17; P < 0.05) and hyperglycemia ( HG; + 0.26; P < 0.005) independently predicted apoL- I level. Hyperglycemic patients ( n = 24) had mean apoL- I levels > 50% higher than normoglycemic subjects ( n = 112; 13.2 vs. 8.3 mug/ml, respectively; P < 0.001). No relationship between apoL- I level and change in CAD was found ( r = 0.06, P = 0.49). Simvastatin- niacin therapy did not alter apoL- I levels ( n = 34; P = 0.27), whereas antioxidant vitamins alone increased apoL- I by > 50% ( n = 36; P < 0.01). Genotyping of a known apoL- I polymorphism ( Lys166Glu) did not independently account for any of the variability in apoL- I levels. In conclusion, we found TG and HG to be the strongest predictors of apoL- I within a dyslipidemic CAD population. These data provide further characterization of the novel HDL-associated apoL- I.