LIPOPROTEIN COMPOSITION AND SERUM APOLIPOPROTEINS IN NORMOGLYCEMIC FIRST-DEGREE RELATIVES OF NON-INSULIN-DEPENDENT DIABETIC-PATIENTS

Cardiovascular disease is the leading cause of death in non-insulin de pendent diabetes mellitus and first degree relatives of such patients are at increased risk of developing diabetes and cardiovascular diseas e. The aim of the present study was to determine whether lipid abnorma lities occur in normoglycaemic relatives of non-insulin dependent diab etic patients. Cholesterol, triglycerides, apolipoprotein A-I and apol ipoprotein B concentrations were measured in serum; the lipoprotein fr actions very low density, intermediate density, low density and high d ensity lipoprotein were prepared by sequential flotation ultracentrifu gation and their composition investigated. The groups were matched for age, sex and blood glucose concentrations although the relatives (n = 126) were more insulin resistant as determined using the homeostasis model assessment method [1.9 (0.8-9.0) vs 1.6 (0.4-4.9) mmol/mU per 1 (mean {95% confidence intervals}); p < 0.001] and had greater body mas s indices [26.6 (4.1) vs 24.8 (3.9) (mean {S.D.}); p = 0.001] than con trol subjects (n = 126). Relatives had higher serum apolipoprotein B c oncentrations than control subjects [0.9 (0.3) vs 0.8 (0.3) g/l, p = 0 .02) and lower serum apolipoprotein A-I concentrations (1.4 (0.3) vs 1 .5 (0.3), p = 0.02). In multivariate linear regression analysis of all subjects log insulin resistance (p = 0.0001), age (p = 0.002) and wai st:hip ratio (p = 0.01) were independent predicators of apolipoprotein B concentrations while waist:hip ratio (p < 0.001) and smoking status (p = 0.002) were independent predictors of apolipoprotein A-I concent rations. Lipoprotein composition (measured in a subgroup of 76 control subjects and 88 relatives), serum cholesterol and serum triglyceride concentrations did not differ between the groups. We conclude that ath erogenic apolipoprotein abnormalities occur in normoglycaemic relative s of non-insulin dependent diabetic patients. (C) 1998 Elsevier Scienc e Ireland Ltd. All rights reserved.