CHARACTERIZATION OF 2 HDL SUBFRACTIONS AND LPA-I, LPA-I-A-II DISTRIBUTION PROFILES AND CLINICAL CHARACTERISTICS OF HYPERALPHALIPOPROTEINEMIC SUBJECTS WITHOUT CHOLESTEROL ESTER TRANSFER PROTEIN-DEFICIENCY

The aims of the present study were (i) to characterize the HDL2, HDL3 and the LpA-I, LpA-I:A-II distribution, (ii) to investigate the preval ence of atheroscIerotic lesions and (iii) to assess the activity of ch olesteryl ester transfer protein (CETP) in 29 hyperalphalipoproteinemi c (HALP) patients (HDL-C = 90 +/- 11 mg/dl) with combined hypercholest erolemia (LDL-C = 180 +/- 16 mg/dl). According to the HDL2/HDL3 and Lp A-I/LpA-I:A-II ratios, two HALP profiles (A and B) were defined: in 22 patients (HALP profile A) these ratios were increased compared to the normolipidemic control subjects (1.19 +/- 0.11 versus 0.53 +/- 0.19, P < 0.001 and 1.01 +/- 0.2 versus 0.51 +/- 0.25, P < 0.001, respective ly) and in seven patients (HALP profile B) these ratios were within th e normal range (0.64 +/- 0.20 and 0.69 +/- 0.2, respectively). The ath erosclerotic lesions were assessed by ultrasonography of the carotid a rteries. Amongst patients with HALP profile A, 17 were free from lesio ns, five had intimal wall thickening and none displayed plaques, where as for patients within the HALP profile B, only one was free from lesi ons, two had intimal wall thickening and four displayed plaques. CETP activities (348 +/- 116 versus 371 +/- 75%/ml/h) and CETP concentratio ns (2.4 +/- 0.5 versus 2.5 +/- 0.6 mu g/ml) were similar in HALP profi les A and B, however these values were both higher than in control sub jects (190 +/- 40%/ml/h, P < 0.001 and 1.8 +/- 0.3 mu g/ml, P < 0.001, respectively). Hence the hyperalphalipoproteinemic profiles (A and B) described here were not related to CETP deficiency. In conclusion, th e HALP profile A was characterized by both increased HDL2/HDL3 and LpA -I/LpA-I:A-II ratios and was associated with a low prevalence of ather osclerosis, whereas the HALP profile B, characterized by HDL2/HDL3 and LpA-I/LpA-I:A-II ratios within the normal range, was less cardioprote ctive. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.