Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, USA.
Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA.
Exp Physiol. 2022 May;107(5):450-461. doi: 10.1113/EP090168. Epub 2022 Apr 12.
What is the central question of the study? Do peripheral and cerebral vascular function differ between young non-Hispanic Black men and women? What is the main finding and its importance? The non-Hispanic Black women in this study presented greater peripheral conduit artery and cerebrovascular reactivity, yet similar peripheral microvascular function relative to the non-Hispanic Black men. These preliminary findings suggest that young Black women and men possess divergent vascular function, possibly contributing to the unique non-Hispanic Black sex differences in cardiovascular and cerebrovascular diseases.
In the USA, cardiovascular and cerebrovascular diseases remain more prominent in the non-Hispanic Black (BL) population relative to other racial/ethnic groups. Typically, sex differences emerge in the manifestation of these diseases, though these differences may not fully materialize in the BL population. While numerous mechanisms are implicated, differences in vascular function likely contribute. Research has demonstrated blunted vasodilatation in several vascular regions in BL versus non-Hispanic White individuals, though much of this work did not assess sex differences. Therefore, this study aimed to ascertain if indices of vascular function are different between young BL women (BW) and men (BM). Eleven BW and 15 BM (22 (4) vs. 23 (3) years) participated in this study. Each participant underwent testing for brachial artery flow-mediated dilatation (FMD), post-occlusive reactive hyperaemia and cerebral vasomotor reactivity during rebreathing-induced hypercapnia. BW exhibited greater adjusted FMD than BM (P < 0.05 for all), but similar or lower reactive hyperaemia when assessed as blood velocity (P > 0.39 for all) or blood flow reactivity (P < 0.05 for all), respectively. Across a range of hypercapnia, BW had greater middle cerebral artery blood velocity and cerebrovascular conductance index than BM (P < 0.001 for both). These preliminary data suggest that young BW have greater vascular function relative to young BM, though this was inconsistent across different indices. These findings provide insight into the divergent epidemiological findings between BM and BW. Further research is needed to elucidate possible mechanisms and relate these physiological responses to epidemiological observations.
研究的核心问题是什么？年轻的非西班牙裔黑人男性和女性的外周和脑血管功能是否存在差异？主要发现及其重要性是什么？本研究中的非裔美国女性表现出更大的外周导血管和脑血管反应性，但相对于非裔美国男性，其外周微血管功能相似。这些初步发现表明，年轻的黑人和男性具有不同的血管功能，这可能导致非裔美国人在心血管和脑血管疾病方面存在独特的性别差异。
在美国，心血管和脑血管疾病在非西班牙裔黑人（BL）人群中的发病率仍然高于其他种族/族裔群体。通常情况下，这些疾病的表现会出现性别差异，但这些差异在 BL 人群中可能并不完全显现。虽然有许多机制被牵涉其中，但血管功能的差异可能起到了作用。研究表明，与非西班牙裔白人相比，BL 个体的几个血管区域的血管舒张功能减弱，但其中许多研究并未评估性别差异。因此，本研究旨在确定年轻的 BL 女性（BW）和男性（BM）之间的血管功能指标是否存在差异。11 名 BW 和 15 名 BM（22（4）岁 vs. 23（3）岁）参加了这项研究。每个参与者都接受了肱动脉血流介导的扩张（FMD）、闭塞后反应性充血和再呼吸诱导性高碳酸血症期间的大脑血管运动反应性的测试。BW 的调整后 FMD 大于 BM（所有 P<0.05），但以血流速度评估时的反应性充血（所有 P>0.39）或血流反应性（所有 P<0.05）相似或较低。在一系列高碳酸血症中，BW 的大脑中动脉血流速度和脑血管导纳指数大于 BM（均 P<0.001）。这些初步数据表明，年轻的 BW 相对于年轻的 BM 具有更大的血管功能，但不同指标之间的一致性不一致。这些发现为 BM 和 BW 之间的不同流行病学发现提供了深入了解。需要进一步的研究来阐明可能的机制，并将这些生理反应与流行病学观察联系起来。
