Assessment of autonomic nervous system function in type 2 diabetes a war of new era

Abstract

The scope of our study is the early identification of Diabetic Autonomic Neuropathy (DAN) which is either clinically evident or sub clinical using simple bedside clinical tests and neuro electrophysiology techniques as there were only a few Indian studies addressing this issue. A total of 66 patients enrolled in the study, done in Saveetha Medical College hospital, Chennai, Tamilnadu for a period of 6 months after applying the inclusion and exclusion criteria,all the patients had type 2 DM of more than 5 years duration, all were above 25 years and below 80 years of age. Basic demographic details collected,blood investigations,ECG were done. Peripheral nervous system was assessed by questionnaire,clinical neurological examination and nerve conduction study. Autonomic function study was done by Cardiovascular Autonomic Reflex Function Tests(Ewing’s battery of five tests) and sympathetic Skin Response (SSR) test. Diagnosis of cardiac autonomic neuropathy was observed in 48.48% patients.27.72% of patients showed positive results for expiration to inspiration ratio,39.39% were found to have 30:15 ratio positive, 37.87% have abnormal valsalva ratio,9.09% had positive results for sustained hand grip, only 6.06% of patients had postural hypotension,Parasympathetic involvement is earlier as compared to sympathetic involvement. A statically significant correlation was found between Nerve Conduction Study and ANS study (p-value is 0.00015). An increasing HBA1C correlates well with early ANS involvement. Recommendations to use simple bed side non-invasive ANS tests helps in early detection of Cardiac autonomic neuropathy (CAN) and prompt early intervention would be clinically meaningful.