Association Between Carotid Artery Response To Cold Pressor Test And Peripheral Vascular Endothelial Function

In healthy individuals, the coronary artery typically responds to the cold pressor test (CPT) with vasodilation, whereas in patients with cardiovascular disease, the coronary arteries constrict in response to the same stimulus. Given the similarity between the coronary artery and carotid artery responses to the CPT, along with the challenges in measuring coronary artery response directly, the carotid artery response to the CPT may be useful as a predictive measure for assessing cardiovascular disease risk. However, the physiological mechanism underlying the differences in carotid artery responses between healthy individuals and those at high risk of cardiovascular disease remain unclear. It is possible that differences in internal carotid artery (ICA) reactivity to the CPT are mirrored by changes in peripheral artery function. PURPOSE: To test our hypothesis, this study aimed to clarify whether individual differences in ICA response to the CPT are associated with variations in peripheral endothelial function and to providing insight into the physiological mechanisms underlying this phenomenon. METHODS:Seventeen young healthy individuals (10 males and 7 females, mean age: 21.8 ± 3.3 years) participated in this study. We measured cerebral and peripheral flow-mediated dilation (FMD) as well as cerebral impedance. Following these measurements, the CPT was conducted, and the response in ICA diameter was assessed using Doppler ultrasound. RESULTS: There was no significant difference in peripheral FMD between participants who exhibited ICA vasodilation (n = 9) and those who exhibited vasoconstriction (n = 8) in response to the CPT (dilation vs. constriction groups, 9.88 ± 5.69% vs. 8.28 ± 1.55%; P = 0.12). No correlation was observed between peripheral FMD and ICA response (r = 0.12, P = 0.96). Additionally, no correlation was found between cerebral FMD (3.98 ± 2.16% vs. 3.61 ± 2.99%; dilation vs. constriction groups), cerebral impedance (0.93 ± 0.19 mmHg·sec·cm-1 vs. 0.98 ± 0.31 mmHg·sec·cm-1; dilation vs. constriction group), and ICA response to the CPT. CONCLUSIONS: These findings suggest that the ICA response to the CPT is not associated with peripheral vascular endothelial function in healthy adults. Supported by: Supported by JSPS KAKENHI 22H03470