Evaluation of Serum Leptin and Microalbuminuria in Patients with Essential Hypertension and Simple Obesity

Abstract

Background: Leptin is a peptide hormon produced by adipocytes responsible for satiety. Hyperleptinaemia is suggested to be an integral component of polymetabolic syndrome and to play an important role in the pathogenesis of hypertension in obesity. Microalbuminuria (MA) is an early symptom of renal injury in essential hypertension.
Material and methods: The study included 2 groups. Group 1 consisted of 30 persons aged 49,0 ± 8,1 (F:M — 19:11) with mild to moderate essential hypertension and obesity (BMI 40,2 ± 6,7 kg/m2); group 2 — 25 persons aged 46,7 ± ± 9,8 (F:M — 15:10) with pure obesity (BMI 38,5 ± 4,0 kg//m2). In both groups we performed antropometric (WHR) and biochemical measurements. Fasting lipid parameters and glicaemia were measured by commertial tests, fasting insulin by RIA (Świerk, Poland), serum leptin by RIA (LINCO Research, USA) and MA by RIA (Euro/DCP Ltd, GB).
Results: In group 1 we found greater values of WHR, fasting insulinaemia, IRI/G, total cholesterol, LDL cholesterol, uric acid, higher prevalence of MA (20 vs 12%) and family history of hypertension (60 vs 40%). In group 1 MA was associated with higher WHR (r = 0,62), systolic blood pressure (r = 0,64), total cholesterol (r = 0,52) and LDL cholesterol (r = 0,54).
Conclusions: 1. The prevalence of MA in obese normotensives was 12%. 2. Presence of hypertension in obese patients nearly doubled prevalence of MA (20%). 3. Relationship between MA and components of polymetabolic syndrome, well documented markers of cardiovascular risk, suggest that MA may also be considered as a cardiovascular risk factor in hypertension associated with obesity. 4. We did not find relationship between leptin level and MA. 5. Revealed correlations support the hypothesis of the role of hyperleptinaemia in the pathogenesis of complications of obesity.