A novel flow-mediated dilation biophysical model for understanding vascular function changes of type 1 diabetes (T1D) patients*

Atherosclerotic changes, such as arterial stiffening and endothelial dysfunction, begin early in individuals with Type 1 Diabetes (T1D), increasing cardiovascular risk. Endothelial function is widely assessed using the Flow-Mediated Dilation (FMD) test, which measures brachial artery diameter noninvasively during blood flow resurgence after brief ischemia. A novel model based on a recent FMD theory was developed to describe vascular function for 77 T1D and 38 healthy subjects from the Laboratory of Integrative Vascular and Exercise Physiology at Augusta University. After image preprocessing and data analysis, FMD percentage and new biophysics parameters were extracted. Diabetes patients exhibited a narrower, and lower distribution of B, indicating reduced artery sensitivity to wall shear stress (WSS), and a lower IQR of gamma, implying weaker mechanotransduction strength, compared to healthy individuals. Regression analysis showed that for diabetes patients, more changes in B and gamma are required for higher vasodilation. Moreover, clinical variables, including CRP, glucose, and HbA1c, correlate differently with FMD parameters in these two groups. Thus, the novel FMD model effectively differentiates between the arterial function of diabetes patients and that of healthy subjects.