Title | Brachial flow-mediated vasodilator responses in population-based research: methods, reproducibility and effects of age, gender and baseline diameter. |
Publication Type | Journal Article |
Year of Publication | 2001 |
Authors | Herrington, DM, Fan, L, Drum, M, Riley, WA, Pusser, BE, Crouse, JR, Burke, GL, McBurnie, MA, Morgan, TM, Espeland, MA |
Journal | J Cardiovasc Risk |
Volume | 8 |
Issue | 5 |
Pagination | 319-28 |
Date Published | 2001 Oct |
ISSN | 1350-6277 |
Keywords | Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, Blood Circulation, Brachial Artery, Female, Humans, Male, Middle Aged, Observer Variation, Population Surveillance, Reproducibility of Results, Sex Factors, Vasodilation, Vasodilator Agents |
Abstract | <p><b>BACKGROUND: </b>Brachial artery ultrasound has been proposed as an inexpensive, accurate way to assess cardiovascular risk in populations. However, analysis and interpretation of these data are not uniform.</p><p><b>METHODS: </b>We analysed the relationship between relative and absolute changes in brachial artery diameter in response to flow-mediated dilation and age, gender and baseline diameter among 4,040 ultrasound examinations from subjects aged 14 to 98 years.</p><p><b>RESULTS: </b>Reproducibility studies demonstrated intra- and interreader and intrasubject correlations from 0.67 to 0.84 for repeated measures of per cent change in diameter. Per cent change in diameter after flow stimulus was 3.58 +/- 0.10% (mean +/- standard deviation). Corresponding values for baseline diameter and absolute change in diameter were 4.43 +/- 0.87 mm and 0.15 +/- 0.01 mm, respectively. Baseline diameter and its variance were inversely related to per cent change in diameter (P< 0.001). In contrast, absolute change in diameter was more uniform throughout the range of baseline diameters. Baseline diameter was directly related, and per cent change in diameter inversely related, to age (P < 0.001 for all three measures). Time to maximum vasodilator response increased with age (P < 0.001). Women (n=2,315) had significantly larger per cent change in diameter than men (n=1,725) (P < 0.001). However, after adjustment for age and baseline diameter, per cent and absolute change were 5% smaller in women than men (P < 0.05 for both). In multivariate analysis, age was overwhelmingly the most important determinant of absolute change in diameter (P < 0.001).</p><p><b>CONCLUSIONS: </b>Automated analysis of brachial flow-mediated vasodilator responses is both feasible and reproducible in large-scale clinical and population-based research.</p> |
DOI | 10.1177/174182670100800512 |
Alternate Journal | J Cardiovasc Risk |
PubMed ID | 11702039 |
Grant List | AG12257 / AG / NIA NIH HHS / United States M01RR07122 / RR / NCRR NIH HHS / United States P60AG10484 / AG / NIA NIH HHS / United States R01HL59503 / HL / NHLBI NIH HHS / United States |