title: Obstructive sleep apnea and aldosterone.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is a major risk factor for hypertension and has been associated with increased risk for cardiovascular morbidity. A dysregulated renin-angiotensin-aldosterone system may contribute to excess sodium retention and hypertension and may be activated in OSA. We tested the hypothesis that serum levels of aldosterone and plasma renin activity (PRA) are increased by apneic sleep in subjects without cardiovascular disease, compared to healthy control subjects.
  
  
  RESULTS
  Plasma aldosterone level was measured in 21 subjects with moderate to severe OSA and was compared to 19 closely matched healthy subjects. Plasma renin activity (PRA) was measured in 19 OSA patients and in 20 healthy controls. Aldosterone and PRA were measured before sleep (9 pm), after 5 hrs of untreated OSA ( 2am) and in the morning after awakening (6 am). There were no baseline (9pm) differences in serum aldosterone levels and PRA between the healthy controls and OSA patients (aldosterone: 55.2 +/- 9 vs 56.0 +/- 9 pg/mL; PRA: 0.99 +/- 0.15 vs. 1.15 +/- 0.15 ng/mL/hr). Neither several hours of untreated severe OSA nor CPAP treatment affected aldosterone levels and PRA in OSA patients. Diurnal variation of both aldosterone and PRA was observed in both groups, in that morning renin and aldosterone levels were higher than those measured at night before sleep.
  
  
  CONCLUSIONS
  Our study shows that patients with moderate to severe OSA without co-existing cardiovascular disease have plasma aldosterone and renin levels similar to healthy subjects. Neither untreated OSA nor CPAP treatment acutely affect plasma aldosterone or renin levels.
authors.affiliation: Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Svatikova
authors.forename: Lyle J
authors.initials: LJ
authors.lastname: Olson
authors.forename: Robert
authors.initials: R
authors.lastname: Wolk
authors.forename: Bradley G
authors.initials: BG
authors.lastname: Phillips
authors.forename: Taro
authors.initials: T
authors.lastname: Adachi
authors.forename: Gary L
authors.initials: GL
authors.lastname: Schwartz
authors.forename: Virend K
authors.initials: VK
authors.lastname: Somers
mesh_terms: D000328:Adult; D000450:Aldosterone / Q000097:blood*; D000704:Analysis of Variance; D002940:Circadian Rhythm; D045422:Continuous Positive Airway Pressure / Q000379:methods; D006801:Humans; D012083:Renin / Q000097:blood; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000628:therapy
chemical_list: D000450:Aldosterone; D012083:Renin