A Study of Cardiac Autonomic Neuropathy in Patient with Diabetes Mellitus

Atherosclerotic coronary artery disease, diabetic cardiomyopathy, and cardiac autonomic neuropathy (CAN) are the three categories into which the cardiovascular consequences of diabetes can be grouped. After all other potential causes have been ruled out, cardiovascular autonomic neuropathy-often referred to as CAN in the literature-is defined as the impairment of autonomic regulation of the cardiovascular system. Finding people with CAN is crucial because, if detected early enough, comprehensive therapies focusing on lifestyle, glucose management, and cardiovascular risk factors can reverse the course of CAN and delay its progression. In order to better understand CAN in individuals with diabetes mellitus (DM) and how it relates to risk factors, the current study was conducted.

Sixty consecutive diabetic patients were selected to be included in our study, diagnosed as per the American Diabetes Association (ADA) and the European Association for the Study of Diabetes. The presence of CAN was assessed with the help of Ewing's Battery, composed of five bedside tests.

Out of 60 patients, a total of 53 patients (88.3%) with DM had CAN. Of these, 38.3% showed early CAN, 38.3% showed definite CAN, and 7% showed severe CAN. The abnormal E:I (exhalation/inhalation) ratio, noticed in 75% of patients, was the most frequently observed abnormal autonomic function test that tests the parasympathetic nervous system. The ECG's QTc interval prolongation provides good specificity for diagnosing CAN as well as assessing its severity, but the majority of cases showed low sensitivity.

Since CAN has a significant association with mortality, every patient diagnosed with DM should be evaluated for CAN at the time of diagnosis as well as on an annual basis thereafter, as recommended by the ADA. Optimal glycemic management and lifestyle modification at the initial stages of diabetes may prevent CAN-related complications.