Multidisciplinary Center UFRJ-Macaé, Federal University of Rio de Janeiro, Macaé, Brazil.
Division of Kinesiology, Health, and Sports Studies, Wayne State University, Detroit, Michigan, United States.
Am J Physiol Regul Integr Comp Physiol. 2024 Sep 1;327(3):R362-R368. doi: 10.1152/ajpregu.00130.2024. Epub 2024 Jul 15.
Near-infrared spectroscopy combined with vascular occlusion test (NIRS-VOT) is a reactive hyperemia technique for in vivo evaluation of skeletal muscle microvascular reactivity. Previous studies using NIRS-VOT have been shown to be able to detect impairments in microvascular function in high-risk cardiovascular disease populations, such as older individuals. It has been demonstrated that older individuals have slower reactive hyperemia compared with young individuals. Importantly, older individuals also show less desaturation during ischemia compared with young individuals. Based on these findings, it has been suggested that the slower reactive hyperemia observed in older individuals is explained by the lower desaturation during blood flow occlusion (reduced ischemic stimulus). This retrospective analysis compared reactive hyperemia in 36 young and 47 older tissue desaturation-matched individuals that underwent 5-min blood flow occlusion. Overall, we showed that older individuals have impaired reactive hyperemia compared with young when matching for the degree of desaturation and blood flow occlusion time. These findings provide evidence that lower tissue desaturation during ischemia is not a major determinant of impaired reactive hyperemia in older individuals. Previous findings have suggested that aging-related impairment in skeletal muscle reactive hyperemia is majorly influenced by a lower degree of tissue desaturation during ischemia in older individuals compared with young individuals. In a retrospective analysis including 83 tissue desaturation-matched individuals, we show that the degree of tissue desaturation is not a major determinant of aging-related impairments in reactive hyperemia.
近红外光谱结合血管闭塞试验（NIRS-VOT）是一种用于评估骨骼肌微血管反应性的活体反应性充血技术。先前使用 NIRS-VOT 的研究表明，它能够检测到高心血管疾病风险人群（如老年人）的微血管功能障碍。已经证明，与年轻人相比，老年人的反应性充血较慢。重要的是，与年轻人相比，老年人在缺血期间的去饱和度也较少。基于这些发现，有人认为，老年人观察到的较慢的反应性充血是由于血流闭塞期间的去饱和度较低（缺血刺激减少）所解释的。这项回顾性分析比较了接受 5 分钟血流闭塞的 36 名年轻和 47 名年龄较大的组织去饱和度匹配个体的反应性充血。总的来说，当匹配去饱和度和血流闭塞时间时，与年轻人相比，老年人的反应性充血受损。这些发现提供的证据表明，在缺血期间组织去饱和度较低不是老年人反应性充血受损的主要决定因素。先前的研究结果表明，与衰老相关的骨骼肌反应性充血受损主要受老年人与年轻人相比缺血期间组织去饱和度较低的影响。在包括 83 个组织去饱和度匹配个体的回顾性分析中，我们表明组织去饱和度的程度不是与衰老相关的反应性充血受损的主要决定因素。
