title: Endothelial dysfunction in obstructive sleep apnea measured by peripheral arterial tone response in the finger to reactive hyperemia.
abstract: OBJECTIVE
  The aim of this study was to investigate endothelial functioning in sleep apnea patients using a novel plethysmographic device that monitors peripheral arterial tone response in the finger to reactive hyperemia induced by forearm ischemia.
  
  
  METHODS
  Forty-six sleep apnea patients, 74.0% men, mean age 46.8 +/- 9.3 years, and 17 control subjects without sleep apnea, 64.7% men, mean age 47.1 +/- 6.7 years.
  
  
  METHODS
  Eight-bed Technion Sleep Medicine Center in Haifa, Israel.
  
  
  METHODS
  Endothelial functioning assessed by the reactive hyperemia peripheral arterial tone index was measured twice, before sleep and after waking from sleep monitored by polysomnography in the laboratory. The reactive hyperemia peripheral arterial tone index was calculated as the average amplitude of the peripheral arterial tone signal after the cuff deflation divided by the average amplitude before the cuff inflation.
  
  
  RESULTS
  Morning index of endothelial functioning was significantly lower in patients with moderate to severe sleep apnea (apnea-hypopnea index > or = 30) than in patients with mild sleep apnea (30 < apnea-hypopnea index < or = 10) and in the control group without sleep apnea (apnea-hypopnea index < 10). The morning index was significantly inversely correlated with apnea-hypopnea index. Patients with a history of hypertension or cardiovascular disease had significantly lower morning and evening indexes of endothelial functioning than patients without such a history. Multivariate analysis revealed that apnea-hypopnea index and sleep efficiency were significant predictors of the morning index.
  
  
  CONCLUSIONS
  Measurements of the response of the peripheral arterial tone in the finger to reactive hyperemia can be used as a substitute for the brachial artery ultrasound technique to measure endothelial functioning in patients with sleep apnea.
authors.affiliation: Lloyd Rigler Sleep Apnea Research Laboratory, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Sarah
authors.initials: S
authors.lastname: Itzhaki
authors.forename: Lena
authors.initials: L
authors.lastname: Lavie
authors.forename: Giora
authors.initials: G
authors.lastname: Pillar
authors.forename: Galit
authors.initials: G
authors.lastname: Tal
authors.forename: Peretz
authors.initials: P
authors.lastname: Lavie
mesh_terms: D000328:Adult; D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology; D004569:Electroencephalography; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D005385:Fingers; D006801:Humans; D006940:Hyperemia / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D010991:Plethysmography; D017286:Polysomnography; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*