Cardiac autonomic neuropathy in patients with diabetes mellitus: current perspectives

Victoria L Fisher,1 Abd A Tahrani2–4 1School of Medicine, University of Nottingham, Nottingham, 2Institute of Metabolism and Systems Research, University of Birmingham, 3Department of Diabetes and Endocrinology, Birmingham Heartlands Hospital, 4Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK Abstract: Cardiac autonomic neuropathy (CAN) is a common and often-underdiagnosed complication of diabetes mellitus (DM). CAN is associated with increased mortality, cardiovascular disease, chronic kidney disease, and morbidity in patients with DM, but despite these significant consequences CAN often remains undiagnosed for a prolonged period. This is commonly due to the disease being asymptomatic until the later stages, as well as a lack of easily available screening strategies. In this article, we review the latest developments in the epidemiology, pathogenesis, diagnosis, consequences, and treatments of CAN in patients with DM. Keywords: cardiovascular, autonomic, neuropathy, orthostatic hypotension, postural hypotension, hyperglycemia, heart-rate variability, sympathetic, parasympathetic, deep breathing, Valsalva ratio, 30:15 ratio, Ewing tests, Ewing criteri