RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM IN PATIENTS WITH ABDOMINAL OBESITY AND ARTERIAL HYPERTENSION

Abstract

Objective. The activity of renin-angiotensin-aldosterone system (RAAS) is increased in patients with ab-dominal obesity (AO). However, till present time it is unclear whether RAAS activation or hypertension (HTN) found in 50 % patients is the primary disorder.Design and methods. We have studied plasma renin activity (PRA), plasma aldosterone concentration (PAC), their ratio PAC/PRA in patients with AO and related HTN and in subjects without AO.Results. PRA was higher in patients with AO versus people without obesity (2,5 ± 0,2 and 1,7 ± 0,7 ng/ml/hr, p = 0,013), there was a tendency to the reduction of the ratio PAC/PRA in obese patients (14,6 ± 0,9 and 19,7 ± 3,3, p = 0,08). In the subgroup of patients with AO and HTN the PRA was higher, and the ratio PAC/PRA was lower than in obese patients without HTN (PRA: 3,3 ± 0,4 and 1,7±0,2 ng/ml/hr, p = 0,005; PAC/PRA: 11,4 ± 1,1 and 17,4 ± 1,4, p < 0,0001). PRA and systolic blood pressure positively correlated. In patients with morbid obesity (3 degree according to the WHO classiication) obesity may play a signiicant role in the increase of RAAS activity, especially in the absence of concomitant HTN. The ratio PAC/PRA in over weight patients with AO was higher than in patients with AO and body mass index ? 30,0 kg/m (17,2 ± 1,7 and 12,5 ± 1,0 kg/m, p = 0,04). PRA was higher only in patients with AO and co-existing hypertension (3,4 ± 0,7 and 1,1 ± 0,2 ng/ml/hr, p = 0,04).Conclusions. RAAS activity is increased in patients with AO, also due to the co-existing HTN. However, in the absence of elevated blood pressure obesity per se may play a signiicant role in RAAS hyperactivity.