Impact of volunteer-related and methodology-related factors on the reproducibility of brachial artery flow-mediated vasodilation: analysis of 672 individual repeated measurements.
J Hypertens
; 34(9): 1738-45, 2016 09.
Article
em En
| MEDLINE
| ID: mdl-27488550
ABSTRACT
OBJECTIVES:
Brachial artery flow-mediated dilation (FMD) is a popular technique to examine endothelial function in humans. Identifying volunteer and methodological factors related to variation in FMD is important to improve measurement accuracy and applicability.METHODS:
Volunteer-related and methodology-related parameters were collected in 672 volunteers from eight affiliated centres worldwide who underwent repeated measures of FMD. All centres adopted contemporary expert-consensus guidelines for FMD assessment. After calculating the coefficient of variation (%) of the FMD for each individual, we constructed quartiles (nâ=â168 per quartile). Based on two regression models (volunteer-related factors and methodology-related factors), statistically significant components of these two models were added to a final regression model (calculated as ß-coefficient and R). This allowed us to identify factors that independently contributed to the variation in FMD%.RESULTS:
Median coefficient of variation was 17.5%, with healthy volunteers demonstrating a coefficient of variation 9.3%. Regression models revealed age (ßâ=â0.248, Pâ<â0.001), hypertension (ßâ=â0.104, Pâ<â0.001), dyslipidemia (ßâ=â0.331, Pâ<â0.001), time between measurements (ßâ=â0.318, Pâ<â0.001), lab experience (ßâ=â-0.133, Pâ<â0.001) and baseline FMD% (ßâ=â0.082, Pâ<â0.05) as contributors to the coefficient of variation. After including all significant factors in the final model, we found that time between measurements, hypertension, baseline FMD% and lab experience with FMD independently predicted brachial artery variability (total Râ=â0.202).CONCLUSION:
Although FMD% showed good reproducibility, larger variation was observed in conditions with longer time between measurements, hypertension, less experience and lower baseline FMD%. Accounting for these factors may improve FMD% variability.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Vasodilatação
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Artéria Braquial
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Técnicas de Diagnóstico Cardiovascular
Tipo de estudo:
Prognostic_studies
Limite:
Adolescent
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Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article