Fasting insulin and leptin serum levels are associated with systolic blood pressure independent of percentage body fat and body mass index.

OBJECTIVE: To examine the relationship between leptin and insulin serum levels and systolic and diastolic blood pressure in young men.
SETTING: Kobe University of Mercantile Marine, Kobe, Japan. PARTICIPANTS: One hundred and ninety-eight male students aged 18-20 years (comprising 100% of those eligible). DESIGN AND MEASUREMENTS: A cross-sectional survey of a sample of male college students was performed, with measurements to include anthropometry, blood pressure and blood tests after overnight fasting.
RESULTS: Compared with 90 men with an optimal blood pressure, 56 men with high-normal and high blood pressure had an increase in body mass index (23.7 +/- 5.2 versus 20.4 +/- 2.2 kg/m2), percentage body fat (21.7 +/- 8.0 versus 16.3 +/- 4.2%) and serum leptin (3.7 +/- 4.7 versus 1.5 +/- 0.8 ng/ml). In addition, they had greater serum insulin (59 +/- 31 versus 43 +/- 12 pmol/l) despite there being no differences in plasma glucose, resulting in a reduction of the ratio of glucose to insulin (x 10(6)) (107 +/- 43 versus 126 +/-, which is an estimate of insulin sensitivity in a nondiabetic population. Furthermore, the 56 men had higher serum triglyceride levels, although there was no difference in low density lipoprotein-cholesterol and high density lipoprotein-cholesterol between men with optimal and high-normal plus high blood pressure. Similar differences were found between men in a top versus low tertile of systolic and diastolic blood pressure. In multiple regression analysis, both log leptin and log insulin emerged as determinants for systolic blood pressure independent of body mass index and percentage body fat, but an association with diastolic blood pressure was only shown for log leptin.
CONCLUSION: Hyperleptinemia and hyperinsulinemia may be regulators of arterial pressure, independent of body mass index or percentage body fat.