Arterial Waveforms Measured at the Wrist as Indicators of Diabetic Endothelial Dysfunction in the Elderly

Although air pressure sensing system (APSS) is a reliable means of assessing vascular endothelial function with high reproducibility, it cannot distinguish between the effects of age and diabetes. This paper aimed at investigating the potential benefit of utilizing signal-processing technique in improving the clinical validity of APSS. Arterial waveforms acquired from the left wrist before and after induction of reactive hyperemia over the left arm were recorded using APSS. Values of dilatation index (DI) were calculated and compared before (DIORIGINAL) and after (DIEEMD) ensemble empirical mode decomposition (EEMD). Compared with DIORIGINAL, DIEEMD showed better negative correlations with anthropometric, hemodynamic, and biochemical parameters (all P <; 0.05). Instead of DIORIGINAL, DIEEMD significantly distinguished between the two groups of testing subjects (P = 0.008). EEMD further refined the validity of DI obtained through APSS, which is a simple self-operable system in evaluating endothelial function for the general public. It may also serve as an assessment tool for clinicians to implement timely therapeutic measures for diabetic patients.