Visceral obesity and insulin resistance are associated with plasma aldosterone levels in women.
OBJECTIVE
Both obesity and insulin resistance increase the risk of hypertension and other cardiovascular diseases, but the mechanisms linking these abnormalities are unknown. The current study was undertaken to examine the effects of obesity, fat distribution, and insulin resistance on plasma levels of aldosterone and other adrenal steroids that might contribute to sequelae of obesity.


METHODS
Twenty-eight normotensive premenopausal women and 27 normotensive men with a wide range of body fat underwent measurements of visceral adipose tissue by CT scan, total fat mass by dual energy X-ray absorptiometry, blood pressure, insulin sensitivity, and plasma levels of three adrenal steroid hormones.


RESULTS
Plasma aldosterone in women correlated directly with visceral adipose tissue (r=0.66, p<0.001) and inversely with insulin sensitivity (r=-0.67, p<0.001), and these associations were independent of plasma renin activity. There were no corresponding correlations in men. Plasma aldosterone was significantly correlated with plasma cortisol and dehydroepiandrosterone sulfate in women. Seventeen women and 15 men completed a weight-reduction regimen, losing an average of 15.1+1.2 kg. After weight loss, plasma aldosterone was significantly lower and insulin sensitivity higher; however, the correlations of aldosterone with visceral adipose tissue and insulin sensitivity in women persisted (p = 0.09 and 0.07, respectively). Although none of the women were hypertensive, blood pressure correlated with plasma aldosterone both before and after weight loss.


CONCLUSIONS
We conclude that visceral adiposity and insulin resistance are associated with increased plasma aldosterone and other adrenal steroids that may contribute to cardiovascular diseases in obese women.
Goodfriend
T L
TL
William S. Middleton Memorial Veterans Hospital and Department of Medicine, University of Wisconsin School of Medicine, Madison, 53705, USA. tgoodfri@facstaff.wisc.edu
Kelley
D E
DE
Goodpaster
B H
BH
Winters
S J
SJ
D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000503:physiopathology*; D000328:Adult; D000450:Aldosterone / Q000097:blood*; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D015992:Body Mass Index; D015331:Cohort Studies; D003687:Dehydroepiandrosterone / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D009765:Obesity / Q000097:blood / Q000503:physiopathology*; D011863:Radioimmunoassay; D012083:Renin / Q000097:blood; D012588:Scintillation Counting; D014057:Tomography, X-Ray Computed
D001786:Blood Glucose; D007328:Insulin; D003687:Dehydroepiandrosterone; D000450:Aldosterone; D012083:Renin; D006854:Hydrocortisone