TY - JOUR
T1 - The association of arterial shear and flow-mediated dilation in diabetes
AU - Gibbs, Bethany Barone
AU - Dobrosielski, Devon A.
AU - Lima, Michael
AU - Bonekamp, Susanne
AU - Stewart, Kerry J.
AU - Clark, Jeanne M.
N1 - Funding Information:
This work was supported by grants from the National Heart, Lung, and Blood Institute (R21-HL095157, 12/01/2008 – 12/01/2010) and the National Institute for Diabetes, Digestive, and Kidney Disorders (R01 DK062368-04, 02/02/04 – 12/31/10).
PY - 2011/8
Y1 - 2011/8
N2 - While adjusting flow-mediated dilation (FMD), a measure of vascular function, for shear rate may be important when evaluating endothelial-dependent vasodilation, the relationship of FMD with shear rate in study populations with cardiovascular risk factors is unclear. We aimed to investigate the association of four measures of shear rate (peak shear rate (SR peak) and shear rate area under the curve through 30 seconds (SR AUC 0-30), 60 seconds (SR AUC 0-60), and time to peak dilation (SR AUC 0-ttp)) with FMD in 50 study subjects with type 2 diabetes and mild hypertension undergoing baseline FMD testing for an exercise intervention trial. Associations among measures of shear rate and FMD were evaluated using Pearson's correlations and R 2. The four measures of shear rate were highly correlated within subjects, with Pearson's correlations ranging from 0.783 (p < 0.001) to 0.972 (p < 0.001). FMD was associated with each measure of shear rate, having a correlation of 0.576 (p < 0.001) with SR AUC 0-30, 0.529 (p < 0.001) with SRAUC 0-60, and 0.512 (p < 0.001) with SRpeak. Nine of 50 subjects (18%) did not dilate following the shear stimulus. Among the 41 responders, FMD had a correlation of 0.517 (p < 0.001) with SR AUC 0-ttp and similar correlations to those found in the full sample for SR AUC 0-30, SR AUC 0-60, and SRpeak. In conclusion, shear rate appears to explain up to a third of between-person variability in FMD response and our results support the reporting of shear rate and FMD with and without adjustment for shear rate in similar clinical populations with CVD risk factors.
AB - While adjusting flow-mediated dilation (FMD), a measure of vascular function, for shear rate may be important when evaluating endothelial-dependent vasodilation, the relationship of FMD with shear rate in study populations with cardiovascular risk factors is unclear. We aimed to investigate the association of four measures of shear rate (peak shear rate (SR peak) and shear rate area under the curve through 30 seconds (SR AUC 0-30), 60 seconds (SR AUC 0-60), and time to peak dilation (SR AUC 0-ttp)) with FMD in 50 study subjects with type 2 diabetes and mild hypertension undergoing baseline FMD testing for an exercise intervention trial. Associations among measures of shear rate and FMD were evaluated using Pearson's correlations and R 2. The four measures of shear rate were highly correlated within subjects, with Pearson's correlations ranging from 0.783 (p < 0.001) to 0.972 (p < 0.001). FMD was associated with each measure of shear rate, having a correlation of 0.576 (p < 0.001) with SR AUC 0-30, 0.529 (p < 0.001) with SRAUC 0-60, and 0.512 (p < 0.001) with SRpeak. Nine of 50 subjects (18%) did not dilate following the shear stimulus. Among the 41 responders, FMD had a correlation of 0.517 (p < 0.001) with SR AUC 0-ttp and similar correlations to those found in the full sample for SR AUC 0-30, SR AUC 0-60, and SRpeak. In conclusion, shear rate appears to explain up to a third of between-person variability in FMD response and our results support the reporting of shear rate and FMD with and without adjustment for shear rate in similar clinical populations with CVD risk factors.
KW - diabetes
KW - endothelial function
KW - shear rate
KW - vascular responsiveness
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U2 - 10.1177/1358863X11411361
DO - 10.1177/1358863X11411361
M3 - Article
C2 - 21708874
AN - SCOPUS:80051658571
VL - 16
SP - 267
EP - 274
JO - Vascular Medicine
JF - Vascular Medicine
SN - 1358-863X
IS - 4
ER -