Insulin, renin-aldosterone system and blood pressure in obese people.
OBJECTIVE
To evaluate the relationship between insulin, the renin-aldosterone system and blood pressure in obese subjects.


METHODS
A cross sectional study of a group of severely obese normotensive subjects who were surgical candidates (n=39; mean BMI: 47.8+/-1.4) and a group of hypertensive patients (n=57; mean BMI: 28.0+/-0.7) twenty-nine of whom had BMI>27. All subjects were studied after 15 days on a balanced diet. Insulin, plasma renin activity and aldosterone were measured.


RESULTS
Fasting insulin, plasma renin activity and aldosterone were higher in severely obese normotensive subjects than in hypertensive subjects (respectively 32.3+/-3.0 vs 13.1+/-1.0 mU/l, P=0.0001; 1.34+/-0.22 vs 0.88+/-0.12 ng/ml/h, P=0.04; 137.2+/-16.2 vs 87.9+/-12.1 pg/ml, P=0.015). Insulin was related to BMI and to aldosterone both in normotensive and in hypertensive patients.


CONCLUSIONS
Hyperinsulinemia itself does not determine hypertension; in some people it could play a vasodilator role in opposition to the renin-aldosterone system.
Andronico
G
G
Istituto di Clinica Medica e Malattie Cardiovascolari, Università di Palermo, Palermo, Italy. androp@unipa.it
Cottone
S
S
Mangano
M T
MT
Ferraro-Mortellaro
R
R
Baiardi
G
G
Grassi
N
N
Ferrara
L
L
Mulé
G
G
Cerasola
G
G
D000328:Adult; D000450:Aldosterone / Q000097:blood*; D001794:Blood Pressure; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006946:Hyperinsulinism; D006973:Hypertension / Q000097:blood / Q000209:etiology; D007328:Insulin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D009767:Obesity, Morbid / Q000097:blood; D012083:Renin / Q000097:blood*; D012084:Renin-Angiotensin System
D007328:Insulin; D000450:Aldosterone; D012083:Renin