Study of Cardiovascular Autonomic Neuropathy in Symptomatic and Asymptomatic Type II Diabetic Patients

Introduction: Cardiovascular autonomic neuropathy (CAN) is the most common and serious complication of diabetes, strongly associated with cardiovascular morbidity and mortality. The patients of early stages of diabetic autonomic neuropathy could be clinically asymptomatic or present with a few symptoms. But, these symptoms become severe and irreversible with the progression of the disease. Hence, this study aimed to identify CAN in symptomatic and asymptomatic diabetic patients. Methodology: This study was conducted on 39 asymptomatic and 35 symptomatic T2DM subjects on their visit to the diabetic clinic OPD. CAN diagnosis and severity were assessed using Ewing's battery and frequency-domain parameters of heart rate variability (HRV). Results: Symptomatic T2DM subjects had higher values of body mass index, waist circumference, and glycemic parameters compared to asymptomatic subjects. Progression of CAN was strongly associated with duration of diabetes and poor glycemic control. CAN was present in 97.1% of symptomatic subjects and 47.2% of asymptomatic subjects with different stages of severity. All frequency-domain parameters of HRV were significantly low in symptomatic subjects except of normalized low frequency and low frequency to high frequency ratio. Conclusion: The severity of CAN was significantly higher in symptomatic subjects. Asymptomatic T2DM subjects also had significant CAN. CAN diagnosis should be done frequently in clinical setup even when the diabetic patients are asymptomatic. So that, appropriate management can be done and delay the progression of CAN as well reverse the condition.