Does Leptin Affect Directly Blood Pressure in Obese Hypertensive Women - Influence of Insulin and Different Methods of Obesity Assessment

Abstract

Background Hyperinsulinemia has been shown to be one of most important pathogenic factors in obesityrelated hypertension. Leptin, a peptide produced in adipose tissue, regulates food intake and energy expenditure. It is also considered to affect blood pressure mainly through sympathetic activation and mitogenic action.
Material and methods 30 untreated obese hypertensive women (group 1) aged 40,7 ± 7,5 years, BMI 35,4 ± 4,9 kg/m² were compared to 30 obese normotensive women (group 2) aged 37,9 ± 6,9 years, BMI 36,3 ± 5,8 kg/m². 10 lean normotensives matched for age constituted the control group. We measured systolic and diastolic blood pressure (SBP, DBP), waist to hip ratio (WHR), fasting serum insulin and leptin (by RIA). Adipose tissue content was assessed by bioelectrical impedance. Results were analysed by multivariate analysis method.
Results In group 1 we found significantly elevated WHR values, serum leptin and insulin. In both groups leptin significantly correlated positively with BMI, fat content, SBP, DBP and insulin. In group 1 after adjustment for BMI and insulin, leptin remained independent predictor of DBP, but this association disappeared after adjustment for adipose tissue content as a measure of fatness.
Conclusions We did not confirm direct relationship between serum leptin and arterial hypertension. Insulin and degree of obesity remain most important factors influencing obesity-related hypertension.