INFLUENCE OF FAMILY HISTORY OF HYPERTENSION ON INSULIN SENSITIVITY INLEAN AND OBESE HYPERTENSIVE SUBJECTS

We evaluated the influence of family history of hypertension on insuli n sensitivity in lean and obese hypertensive subjects (H): 40 lean [bo dy mass index (BMI) less than or equal to 25 kg m(-2)] H with normoten sive parents (F-), 50 lean H with one or two parents hypertensive (F+) , 30 obese HF- (BMI greater than or equal to 30 kg m(-2)) and 35 obese HF+. The four groups were comparable in terms of age, sex and ambulat ory blood pressure values. We evaluated glucose, insulin and C-peptide before and 30, 60, 90 and 120 min after an oral glucose load, insulin sensitivity index (ISI, fasting glucose/insulin ratio), fasting insul in/C-peptide ratio (I/Cp). Glucose, fasting and during test, and I/Cp were similar among the four groups; insulin and C-peptide, fasting and stimulated, were significantly higher and ISI lower in obese H than i n lean H; at similar BMI, insulin and C-peptide were significantly hig her in F+ than in F-. Insulin directly correlated with night-time bloo d pressure only in lean HF-. The correlation between insulin and BMI w as significantly closer in F- than in F+. In conclusion, family histor y of hypertension appears to play a relevant role in insulin sensitivi ty in hypertensive subjects also in the presence of obesity.