title: Short duration of reactive hyperemia in the forearm of subjects with multiple cardiovascular risk factors.
abstract: BACKGROUND
  Peripheral vascular endothelial dysfunction is an independent predictor of cardiovascular events, and can be assessed noninvasively by measuring reactive hyperemia, either by vascular ultrasound measurement of flow-mediated vasodilatation or, less commonly, by measurement of blood flow using plethysmography. In the present study reactive hyperemia was measured using plethysmography in healthy subjects with multiple cardiovascular risk factors.
  
  
  RESULTS
  Reactive hyperemia was measured following 5-min occlusion of the upper arm in 449 healthy subjects (302 men, 147 women, age range 20-70 years) with (n=352) and without (n=97) risk factors such as smoking, hypertension, diabetes mellitus, hypercholesterolemia, obesity, family history of cardiovascular disease, and menopause. Maximum blood flow and minimum vascular resistance in reactive hyperemia did not differ between subjects with and without risk factors regardless of gender. Duration of reactive hyperemia, however, was significantly shorter in subjects with risk factors. Age-adjusted mean value of duration of reactive hyperemia was significantly smaller in men with a smoking habit, diabetes mellitus, hypercholesterolemia or obesity, and in women with smoking habit, hypertension, diabetes mellitus or obesity. The number of risk factors significantly correlated with the duration of reactive hyperemia in both men (r=-0.56, p<0.001) and women (r=-0.62, p<0.001), suggesting that endothelial dysfunction increases with the number of risk conditions clustering in a single individual.
  
  
  CONCLUSIONS
  Duration of reactive hyperemia reflects cardiovascular risk factors and decreases with the number of risk conditions. These findings suggest that the duration of reactive hyperemia measured with plethysmography is potentially useful for assessing endothelial dysfunction.
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Shimane University Faculty of Medicine, Izumo, Japan. yuyu@med.shimane-u.ac.jp
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Ishibashi
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Toshio
authors.initials: T
authors.lastname: Shimada
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugamori
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sakane
authors.forename: Tetsuhiro
authors.initials: T
authors.lastname: Umeno
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Hirano
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Oyake
authors.forename: Yo
authors.initials: Y
authors.lastname: Murakami
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D003920:Diabetes Mellitus / Q000188:drug therapy; D005260:Female; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology*; D006949:Hyperlipidemias / Q000188:drug therapy; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D012307:Risk Factors; D012907:Smoking