Second Derivative and Contour Analysis of PPG for Diabetic Patients

Diabetes mellitus is a group of metabolic diseases associated with the production and/or reaction of insulin leading to hyperglycemia. Glycated hemoglobin (HbA1c) level is generally measured for hyperglycemia. Hyperglycemia and the duration of having diabetes are two factors that contribute to developing complications. A trend of increasing arterial stiffness has been identified in Type 2 diabetes. Photoplethysmograph (PPG) pulse wave provides a `window' into the properties of small arteries whereas stiffening of these arteries will alter the PPG waveform. In this research, the potential of PPG in discriminating type 2 diabetic patients between two different levels of HbA1c has been investigated (diabetic patient with HbA1c <; 8% as controlled group and diabetic patient with HbA1c > 10% as unhealthy group). Contour analysis of PPG signal and second derivative photoplethysmograph (SDPPG) techniques have been used to identify the feasible parameter for this research. From this study, it shows that there is no significant difference for both group of diabetic patient for ratio of b/a, which extracted from SDPPG. The mean ratio for controlled group is 0.5692 and 0.6067 for unhealthy group, p=0.180. Other than that, the results show that there is a statistical significant different for the some variables extracted.