title: Body mass index predicts aldosterone production in normotensive adults on a high-salt diet.
abstract: BACKGROUND
  The mechanisms underlying obesity-mediated cardiovascular disease are not fully understood. Aldosterone and insulin resistance both are associated with obesity and cardiovascular disease.
  
  
  OBJECTIVE
  The objectives of this study were to test the hypotheses that aldosterone production is elevated and associated with insulin resistance in overweight adults on a high-sodium diet.
  
  
  METHODS
  Healthy normotensive adults were categorized as lean body mass index (BMI) less than 25 kg/m(2) (n = 63) or overweight BMI 25 kg/m(2) or greater (n = 57). After 7 d of a high-sodium diet, participants fasted overnight and remained supine throughout hemodynamic and laboratory assessments and angiotensin II (AngII) stimulation.
  
  
  RESULTS
  The overweight group, compared with the lean group, had higher 24-h urinary aldosterone (9.0 +/- 0.8 vs. 6.6 +/- 0.5 microg per 24 h; P = 0.003) and higher AngII-stimulated serum aldosterone (11.4 +/- 1.0 vs. 9.0 +/- 0.6 ng/dl; P = 0.04). There were no differences in 24-h urinary cortisol or sodium or supine measurements of plasma renin activity, serum aldosterone, or serum potassium. The homeostasis model assessment of insulin resistance was predicted by urinary aldosterone excretion (r = 0.32, P = 0.03) and serum aldosterone response to AngII stimulation (r = 0.28, P = 0.02) independent of age and BMI.
  
  
  CONCLUSIONS
  Urinary aldosterone excretion and AngII-stimulated aldosterone are increased in overweight, compared with lean, normotensive adults. The correlation of these measures of aldosterone production with insulin resistance suggests a potential role for aldosterone in the pathophysiology of obesity-mediated insulin resistance.
authors.affiliation: Division of Endocrinology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Rhonda
authors.initials: R
authors.lastname: Bentley-Lewis
authors.forename: Gail K
authors.initials: GK
authors.lastname: Adler
authors.forename: Todd
authors.initials: T
authors.lastname: Perlstein
authors.forename: Ellen W
authors.initials: EW
authors.lastname: Seely
authors.forename: Paul N
authors.initials: PN
authors.lastname: Hopkins
authors.forename: Gordon H
authors.initials: GH
authors.lastname: Williams
authors.forename: Rajesh
authors.initials: R
authors.lastname: Garg
mesh_terms: D000328:Adult; D000450:Aldosterone / Q000096:biosynthesis* / Q000097:blood / Q000652:urine; D000804:Angiotensin II / Q000008:administration & dosage / Q000494:pharmacology; D015992:Body Mass Index; D004032:Diet; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007262:Infusions, Intravenous; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000378:metabolism; D012083:Renin / Q000097:blood; D012982:Sodium, Dietary / Q000494:pharmacology*; D014662:Vasoconstrictor Agents / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D012982:Sodium, Dietary; D014662:Vasoconstrictor Agents; D000804:Angiotensin II; D000450:Aldosterone; D012083:Renin; D006854:Hydrocortisone