title: Test-retest reliability of peripheral arterial tonometry in the metabolic syndrome.
abstract: Endothelial dysfunction is an important contributor to atherosclerosis and cardiovascular disease. However, routine assessment via angiography or flow-mediated dilation is difficult due to technical limitations. Peripheral arterial tonometry (PAT) is a promising alternative method for non-invasive assessment of endothelial dysfunction. This study assessed the test-retest reliability of PAT in adults with the metabolic syndrome (n = 20) and provides sample size and power estimates for study design. Participants completed five PAT tests each separated by 1 week. The PAT-derived reactive hyperaemia index (RHI) showed robust repeatability (intra-class correlation = 0.74). A parallel-arm study powered at 0.90 would require 22 participants to detect an absolute change in RHI of 0.40 units (equal to ~25% change in this sample), whereas a crossover study would require 12 participants. In conclusion, we have demonstrated that PAT can be used to assess endothelial dysfunction in adults with the metabolic syndrome as reliably as in healthy samples.
authors.affiliation: Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA, USA.
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Sauder
authors.forename: Sheila G
authors.initials: SG
authors.lastname: West
authors.forename: Cindy E
authors.initials: CE
authors.lastname: McCrea
authors.forename: Janice M
authors.initials: JM
authors.lastname: Campbell
authors.forename: Alexandra L
authors.initials: AL
authors.lastname: Jenkins
authors.forename: David J A
authors.initials: DJ
authors.lastname: Jenkins
authors.forename: Cyril W C
authors.initials: CW
authors.lastname: Kendall
mesh_terms: D000328:Adult; D000368:Aged; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006225:Hand / Q000098:blood supply*; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology*; D008297:Male; D008365:Manometry; D024821:Metabolic Syndrome / Q000503:physiopathology*; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000503:physiopathology*; D015203:Reproducibility of Results; D059289:Vascular Stiffness
keywords: Peripheral arterial tonometry; endothelial function; metabolic syndrome; reliability