title: Obesity and insulin resistance but not hyperandrogenism mediates vascular dysfunction in women with polycystic ovary syndrome.
abstract: OBJECTIVE
  Polycystic ovary syndrome (PCOS) is associated with biochemical evidence of early atherosclerosis; however, data regarding vascular function are controversial. We hypothesized that resistance vessel function (mediated by the endothelium or smooth muscle) would be impaired in women with PCOS and aimed to determine the contribution of hyperandrogenism, obesity, or insulin resistance to vascular dysfunction.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  University practice.
  
  
  METHODS
  Women with PCOS (n = 24) and age/weight-matched controls (n = 22).
  
  
  METHODS
  Vascular function was assessed by measuring forearm vasodilatation in response to both endothelium-dependent (acetylcholine/bradykinin) and endothelium-independent dilators (nitroprusside/verapamil).
  
  
  METHODS
  Resistance vessel function.
  
  
  RESULTS
  Forearm vasodilatation to all four drugs was reduced (>50%) in obese PCOS compared to lean PCOS subjects. There was no significant difference in vascular function between obese or lean women with PCOS compared to corresponding controls. Androgen levels did not correlate with vascular function. Stepwise regression analysis showed that body mass index (BMI) contributed maximally to vascular dysfunction (R(2) = 0.47).
  
  
  CONCLUSIONS
  This comprehensive study demonstrates for the first time that obese women with PCOS have markedly reduced vascular smooth muscle function compared to lean subjects with PCOS. In our study obesity and insulin resistance, but not hyperandrogenism, appeared to be significant modulators of vascular function.
authors.affiliation: Department of Obstetrics & Gynecology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52246, USA. anuja-dokras@uiowa.edu <anuja-dokras@uiowa.edu>
authors.forename: Anuja
authors.initials: A
authors.lastname: Dokras
authors.forename: Dinesh H
authors.initials: DH
authors.lastname: Jagasia
authors.forename: Michelle
authors.initials: M
authors.lastname: Maifeld
authors.forename: Christine A
authors.initials: CA
authors.lastname: Sinkey
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: VanVoorhis
authors.forename: William G
authors.initials: WG
authors.lastname: Haynes
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000503:physiopathology*; D007006:Hypogonadism / Q000503:physiopathology*; D007333:Insulin Resistance; D009765:Obesity; D011085:Polycystic Ovary Syndrome / Q000503:physiopathology*; D014652:Vascular Diseases / Q000503:physiopathology*; D014655:Vascular Resistance