title: High-flow-mediated constriction in adults is not influenced by biomarkers of cardiovascular and metabolic risk.
abstract: OBJECTIVE
  During reactive hyperemia, the brachial artery in some individuals constricts prior to dilation. Our aim was to describe the frequency of high-flow-mediated constriction (H-FMC) in adults, and its relationship to body composition and biomarkers of cardiovascular and metabolic risk.
  
  
  METHODS
  Two hundred forty-six adults (124 male, 122 female; 36 ± 7 years old) were assessed for H-FMC via sonographic imaging of the brachial artery. Blood pressure, glucose, insulin, lipids, and body composition assessed via dual energy X-ray absorptiometry were collected. H-FMC was characterized as a 10-second average of maximal postocclusion constriction. Independent t test was used to compare H-FMC versus non-H-FMC individuals.
  
  
  RESULTS
  H-FMC was observed in approximately 69% of adult participants (54 obese, 57 overweight, and 59 normal weight). Total body mass (82.3 ± 17.5 versus 76.3 ± 16.3 kg, p = 0.012), fat mass (27.7 ± 11.5 versus 23.8 ± 10.5 kg, p = 0.012), body mass index (27.7 ± 4.9 versus 26.1 ± 5.0 kg/m2, p = 0.018), and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (2.41 ± 1.03 versus 2.09 ± 0.72, p = 0.007) were higher in H-FMC than in non-H-FMC individuals. Flow-mediated dilatation (FMD) (6.12 ± 3.48 versus 8.09 ± 3.02%, p < 0.001) was lower in H-FMC subjects. However, there was no difference in brachial artery dilation between groups (7.57 ± 3.69 versus 8.09 ± 3.02%, p = 0.250) when H-FMC was added to FMD.
  
  
  CONCLUSIONS
  Increased body mass, fat mass, and body mass index were associated with a greater H-FMC. When H-FMC was present, the FMD response to reactive hyperemia was significantly lower. Because H-FMC has been observed to negatively affect FMD response to reactive hyperemia, we suggest that H-FMC should be noted when analyzing and interpreting FMD data. H-FMC may be an ancillary measure of endothelial health. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:35-42, 2017.
authors: Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, 55455.
authors: Joseph D
authors: JD
authors: Ostrem
authors: Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, 55455.
authors: Nicholas G
authors: NG
authors: Evanoff
authors: Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, 55455.
authors: Justin R
authors: JR
authors: Ryder
authors: Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, 55455.
authors: Julia
authors: J
authors: Steinberger
authors: Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, 55455.
authors: Alan R
authors: AR
authors: Sinaiko
authors: Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, 55455.
authors: Katie L
authors: KL
authors: Bisch
authors: Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, 55455.
authors: Niklas M
authors: NM
authors: Brinck
authors: Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, 55455.|Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, 55455.
authors: Donald R
authors: DR
authors: Dengel
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood*; D001783:Blood Flow Velocity; D001823:Body Composition; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology; D050177:Overweight / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology; D012039:Regional Blood Flow; D014463:Ultrasonography; D014661:Vasoconstriction / Q000502:physiology*; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: adults; flow-mediated dilation; reactive hyperemia; ultrasound