Independent association of plasma leptin levels and left ventricular isovolumic relaxation in uncomplicated hypertension

Background: On the basis of evidence of plasma leptin (LE) effects on cardi ovascular system, we assessed possible association of LE and Doppler-derive d left ventricular (LV) diastolic function in arterial hypertension. Methods: Doppler echocardiography, blood sample for fasting plasma LE level s, and euglycemic hyperinsulinemic glucose clamp were performed on 15 healt hy insulin-sensitive men and 40 newly diagnosed hypertensive men, who were divided into two groups according to insulin sensitivity degree: 15 insulin sensitive (IS) and 25 insulin resistant (IR) individuals (whole body gluco se disposal >33.3 and <33.3 <mu>mol/kg, respectively). Results: The IR hypertensives had significantly higher body mass index (BMI ), waist/hip ratio, LE and LV mass index than the other two groups. IR hype rtensives had lower LE (even after adjusting for BMI and waist/hip ratio) a nd among LV diastolic indexes, lower E peak velocity (P < .05) and longer i sovolumic relaxation time (IVRT) (P < .001) in comparison to IR hypertensiv es. IR hypertensives had the lowest E/A ratio (0.88 +/- 0.2) compared to IS patients (1.03 +/- 0.1 P < .05) and controls (1.31 <plus/minus> 10.2 P < . 001). By multiple linear regression analyses performed both in the overall population and hypertensives, LV mass index and LE were independently assoc iated to IVRT (R-2 = 0.41 in overall population, R-2 = 0.42 in hypertensive s, both P < .0001), whereas age, heart rate, diastolic and systolic blood p ressure (BP), BMI, waist/hip ratio, and insulin action were not significant . Conclusions: Our study underscores an independent association of increased plasma LE and lengthening of isovolumic relaxation in uncomplicated hyperte nsion. Further studies will need to understand the conditions underlying bo th these phenomena. Am J Hypertens 2001;14: 1019-1024 (C) 2001 American Jou rnal of Hypertension, Ltd.