title: Association between serum concentrations of nitric oxide and transition to menopause.
abstract: OBJECTIVE
  Menopausal status may increase cardiovascular disease (CVD) risk. Nitric oxide plays a role in the protection against CVD onset and progression but has not been studied around the time of menopause. We investigated associations between serum nitric-oxide metabolite (NOx) concentrations and menopausal status.
  
  
  METHODS
  Comparative case-control cross-sectional study.
  
  
  METHODS
  Tehran Lipid and Glucose Study, university center.
  
  
  METHODS
  Sub-groups from a cohort of 2137 women, of whom 213 met enrollment criteria.
  
  
  METHODS
  We studied four sub-groups in a 1.2 ratio: (1) post-menopausal women (n = 29) with natural amenorrhea for 13-24 months, (2) age- and BMI-matched controls (n = 58) with regular menstrual cycles; (3) peri-menopausal women (n = 42) with natural amenorrhea for 1-12 months, and (4) age- and BMI-matched women as controls for the last group of women (n = 84).
  
  
  METHODS
  Serum nitric oxide concentrations.
  
  
  RESULTS
  Medians (inter-quartile ranges) of NOx in post-menopausal women and their controls were 31 (21.7-40.2) and 23.5 (17.2-31) μmol/L, respectively (p = 0.012). In peri-menopausal women and their controls the medians (inter-quartile ranges) were 28 μmol/L (18.5-50.5) and 25 (20-31.25) μmol/L, respectively (p = 0.035), but were not significantly different between peri- and postmenopausal women and were unchanged after adjustment for lipids. In a conditional fixed-effect logistic regression model, the risk of "transition to menopause" and "menopause" rose respectively 2.44- and 2.27-fold for a one-score increase in the NOx standard deviation.
  
  
  CONCLUSIONS
  Menopausal status, by itself and not as a consequence of aging, is associated with increased serum nitric oxide concentrations. Identification of variables associated with menopausal cardiovascular consequences may be used to improve women's health after menopause.
authors: Reproductive Endocrinology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Fahimeh
authors: F
authors: Ramezani Tehrani
authors: Reproductive Endocrinology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Samira
authors: S
authors: Behboudi-Gandevani
authors: Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Asghar
authors: A
authors: Ghasemi
authors: Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Fereidoun
authors: F
authors: Azizi
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002784:Cholesterol / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008593:Menopause / Q000097:blood*; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood*; D014280:Triglycerides / Q000097:blood
chemical_list: D014280:Triglycerides; D009569:Nitric Oxide; D002784:Cholesterol
keywords: Cardiovascular disease; aging; menopause; nitric oxide; peri-menopause