Measuring Arterial Stiffness Using Photoplethysmogram

Monitoring of the arterial condition promises an advantage in detection of any abnormalities occurred among diabetic patients. In this study, the characteristic of photoplethysmogram (PPG) has been investigated non-invasively to measure the status of arterial stiffness. A total of 101 Type 2 diabetic patients, aged 50 to 70 year were participated in this study. The patients divided into two groups which Group 1 consist of patients with HbA1c<8% and those with HbA1c>10% is in Group 2. An area under curve (auc-PPG) has been investigated and chosen as PPG parameter. An independent sample t-test used to compare an auc-PPG between two levels of HbA1c which are HbA1c<8%(Group 1) and HbA1c>10%(Group 2). The result shows that auc-PPG has been found significantly higher among diabetic subjects with HbA1c<8% than those with HbA1c>10% (Group 1 (M=0.455, SD=0.068), Group 2 (M=0.403, SD=0.067), p<0.0001). Further analysis is carried out to investigate the effect of age on auc-PPG. As a result, the mean values of auc-PPG is still significantly higher among diabetic patient with HbA1c<8% than those with HbA1c>10% (Group 1 (M=0.453, SD=0.009), Group 2 (M=0.405, SD=0.009), p<0.0001). The auc-PPG could be considered as one parameter in determining the status of arterial stiffness in relation to the level of HbA1c. Keywords— Atherosclerosis, Cardiovascular disease, Diabetes mellitus, Vascular endothelium, Photoplethysmogram.