Microvascular responses during reactive hyperemia assessed by near-infrared spectroscopy and arterial stiffness in young, middle-aged, and older women

摘要

We investigated the effects of age on microvascular responses during reactive hyperemia and arterial stiffness in 13 young (22 +/- 1 years), 12 middle-aged (42 +/- 5 years), and 15 older (63 +/- 2 years) women. During the vascular occlusion test (VOT), forearm tissue oxygen saturation (StO(2)) was measured using near-infrared spectroscopy (NIRS). During reperfusion, the area under the curve (AUC) during hyperemia in young women (1123 +/- 208% s) was significantly greater than that in middle-aged (771 +/- 445% s, P = 0.024) and older women (619 +/- 356% s, P = 0.001) with no differences between middle-aged and older women (P = 0.265). Cardio-ankle vascular index (CAVI) as an indicator of arterial stiffness was assessed using four-limb oscillometry. CAVI significantly increased with age (8.1 +/- 0.7 in the older group, 6.0 +/- 0.8 in the middle-aged group, and 5.8 +/- 0.4 in the young group), with significant differences between older women and women in the other groups (P < 0.001); however, no differences in CAVI between young and middle-aged women (P = 0.484) were found. When the data of all groups were pooled, the AUC or upslope was associated with CAVI or body mass index or mean arterial pressure (all P < 0.05). To conclude, the AUC derived by NIRS measures of StO(2) during the reperfusion phase can be used as one of the evaluations of microvascular function, followed by the development of atherosclerosis in middle-aged and older women.