Diabetic autonomic neuropathy (DAN) is a serious and often underestimated complication of diabetes. Due to its ability to potentially affect any tract of autonomic nervous system, DAN is a systemic-wide disorder, which encompasses a large spectrum of organs and leads to significant increase in morbidity and mortality. Subclinical DAN can occur within a year of diagnosis in T2DM and within 2 years in T1DM, while first symptoms may onset after years.The most common and studied manifestation of DAN is cardiovascular autonomic neuropathy (CAN), owing to its life-threatening complications (arrhythmias, silent myocardial ischemia, and sudden death) and to its relation with other microangiopathic comorbidities.  Diabetic neuropathy is classically defined as “the presence of symptoms and/or signs of peripheral nerve dysfunction in people with diabetes after the exclusion of other causes”.  Sensory, motor, or autonomic nerves can be involved, often coexisting.The reported prevalence of DAN varies widely depending on the cohort studied and the methods of assessment. In randomly selected cohorts of asymptomatic individuals with diabetes, ∼20% had abnormal cardiovascular autonomic function. DAN frequently coexists with other peripheral neuropathies and other diabetic complications, but DAN may be isolated, frequently preceding the detection of other complications. DAN may affect many organ systems throughout the body (e.g., gastrointestinal [GI], genitourinary, and cardiovascular). Major clinical manifestations of DAN include resting tachycardia, exercise intolerance, orthostatic hypotension, constipation, gastroparesis, erectile dysfunction, sudomotor dysfunction, impaired neurovascular function, “brittle diabetes,” and hypoglycemic autonomic failure.

However, studies probing autonomic neuropathy dysfunctions in diabetic patients in Indian scenario are scare. Addressing this dearth, the present prospective observational study has been planned to understand autonomic neurodeficit in a cohort of type 2 diabetes mellitus (T2DM) patients attending the outpatient department of a tertiary care hospital.