In healthy adults, associations among different measures of peripheral micro- and macrovascular reactivity were modest, with more than 75% of measures showing no significant association.
Cross-Sectional (n=40)
No
Do different noninvasive measures of postischemic macro- and microvascular reactivity correlate with each other in healthy adults?
Associations among different noninvasive measures of peripheral micro- and macrovascular reactivity are modest, suggesting they evaluate different physiological mechanisms.
Effect estimate: r = 0.47
p-value: p=<0.01
The clinical importance of vascular reactivity as an early marker of atherosclerosis has been well established, and a number of established and emerging techniques have been employed to provide measurements of peripheral vascular reactivity. However, relations between these methodologies are unclear as each technique evaluates different physiological aspects related to micro- and macrovascular reactive hyperemia. To address this question, a total of 40 apparently healthy normotensive adults, 19-68 yr old, underwent 5 min of forearm suprasystolic cuff-induced ischemia followed by postischemic measurements. Measurements of vascular reactivity included 1) flow-mediated dilatation (FMD), 2) changes in pulse wave velocity between the brachial and radial artery (DeltaPWV), 3) hyperemic shear stress, 4) reactive hyperemic flow, 5) reactive hyperemia index (RHI) assessed by fingertip arterial tonometry, 6) fingertip temperature rebound (TR), and 7) skin reactive hyperemia. FMD was significantly and positively associated with RHI (r=0.47) and TR (r=0.45) (both P<0.01) but not with reactive hyperemic flow or hyperemic shear stress. There was no correlation between two measures of macrovascular reactivity (FMD and DeltaPWV). Skin reactive hyperemia was significantly associated with RHI (r=0.55) and reactive hyperemic flow (r=0.35) (both P<0.05). There was a significant association between reactive hyperemia and RHI (r=0.30; P<0.05). In more than 75% of cases, vascular reactivity measures were not significantly associated. We concluded that associations among different measures of peripheral micro- and macrovascular reactivity were modest at best. These results suggest that different physiological mechanisms may be involved in changing different measures of vascular reactivity.
Dhindsa et al. (Fri,) conducted a cross-sectional in Healthy normotensive adults (n=40). Postischemic macro- and microvascular reactivity measures was evaluated on Correlation between flow-mediated dilatation (FMD) and reactive hyperemia index (RHI) (r = 0.47, p=<0.01). In healthy adults, associations among different measures of peripheral micro- and macrovascular reactivity were modest, with more than 75% of measures showing no significant association.