title: Vascular Endothelial Function Assessed by Postischemic Diastolic Blood Pressure Is Associated with Acclimatization and Acute Mountain Sickness.
abstract: BACKGROUND
  This study assessed whether the brachial diastolic blood pressure (DBP) decline induced by 5-minute arm ischemia is associated with acclimatization and acute mountain sickness (AMS).
  
  
  METHODS
  Forty-two age- and body mass index-matched young male residents at sea level (<400 m) or moderate altitude (1000-2000 m above sea level) were enrolled. All subjects had never been to 3200 m before. Brachial BP was measured at a station at 1380 m altitude before and 1, 5, and 10 minutes after right arm ischemia. AMS score was evaluated after 3-day training at a high altitude of 3200 m.
  
  
  RESULTS
  In moderate altitude versus sea-level residents: (1) systolic BP curves for both arms overlapped well; (2) mean right arm DBP decline post right arm ischemia was larger, while left arm, which was not subjected to ischemia, did not show DBP decline in either group; and (3) AMS scores were significantly lower (3.19 ± 2.16 vs. 5.52 ± 4.58, p = 0.043) in those residing at moderate altitude compared to those from low altitude. There was a low negative correlation between AMS score and right arm area between curves-DBP (r = -0.320, p = 0.039).
  
  
  CONCLUSIONS
  Moderate altitude relative to sea-level residents had a larger mean postischemic DBP decline in weak but significant association with lower mean AMS score at 3200 m. These data suggest that differences in vascular endothelial function related to altitude of residence persist during travel to high altitude and might contribute to AMS risk.
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Nanchang University , Nanchang, Jiangxi, China .
authors.forename: Lipeng
authors.initials: L
authors.lastname: He
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Nanchang University , Nanchang, Jiangxi, China .
authors.forename: Yu
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Nanchang University , Nanchang, Jiangxi, China .
authors.forename: Hai
authors.initials: H
authors.lastname: Su
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Nanchang University , Nanchang, Jiangxi, China .
authors.forename: Juxiang
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Nanchang University , Nanchang, Jiangxi, China .
authors.forename: Xiaoshu
authors.initials: X
authors.lastname: Cheng
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000293:Adolescent; D000531:Altitude; D000532:Altitude Sickness / Q000209:etiology*; D001132:Arm / Q000098:blood supply*; D001794:Blood Pressure; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D007511:Ischemia / Q000150:complications / Q000503:physiopathology*; D008297:Male; D055815:Young Adult
keywords: acute hypoxia; exercise; expeditions to high altitude; flow-mediated vasodilatation