and Non-Clinical Settings in the United States and China
Distribution of Microvascular Endothelial Function in Different Clinical and Non-Clinical Settings in the United States and China
Leila Messahli, Endothelix, Houston, TX; Yasamin Naghavi, Ahmed Gul, Maha Gul, Ruoyu Zhuang, Univ of Houston, Houston, TX; Albert Yen, Endothelix, Houston, TX; Hirofumi Tanaka, Univ of Texas Austin, Austin, TX; Ralph Metcalfe, Stanley Kleis, Univ of Houston, Houston, TX; Morteza Naghavi, SHAPE, Palo Alto, CA
Background: Despite the fact that microvascular (endothelial) dysfunction is associated with various diseases from cardiovascular to kidney, lung, liver, and other medical conditions, it has not been extensively studied in various clinical and non-clinical settings as blood pressure has . Digital Thermal Flowmetry (DTF) of microvascular endothelial function is a new and automated technique based on monitoring fingertip temperature fall and rebound during reactive hyperemia. Here we report distributions of microvascular function across (1) CVD patients, (2) wellness and internal medicine clinics, (3) college students, and (4) community based healthy volunteers in China.
Methods: A total of 7,907 endothelial function test results were collected from various settings. Blood pressure and heart rate were measured before the tests. The tests were conducted using FDA-approved automated VENDYS devices (Endothelix Inc., Palo Alto, CA). Adjusted maximum temperature rebound was reported as Vascular Reactivity Index (VRI) and compared across different settings.
Results: VRI in CVD patients, wellness & internal medicine clinics, college students and Chinese volunteers were (1.25±0.34) (1.53±0.5) (1.86±0.5) (1.95±0.44.) respectively P<0.01. Age was weakly correlated with VRI with the equation age=-0.01 VRI+2.01 (r=0.17 p<0.001)
Conclusions: To our knowledge this is the largest database of finger-based endothelial function testing. VRI showed distinct distributions across various clinical and non-clinical settings with CVD patients exhibiting the lowest and Chinese healthy volunteers the highest values. The VRI trend mimics statistically expected risk trend with CVD patients having the highest and Chinese healthy volunteers the lowest CVD events risk.
Examples of Good – Average – Poor Endothelial Function Measured by VRI: