A condition affecting the nerves that innervate the heart and blood vessels. Diabetic autonomic neuropathy also can affect a number of organ systems throughout the body, including the digestive tract, bladder, and sex organs. Cardiac autonomic neuropathy (CAN) can cause abnormalities in the regulation of heart rate and blood pressure. The clinical signs and symptoms of CAN include tachycardia (abnormally rapid heartbeat) during rest, exercise intolerance (blunted cardiac output in response to activity), and orthostatic hypotension (a drop in blood pressure upon standing). CAN also may blunt the symptoms of a heart attack and increase a person’s risk of sudden cardiac death.
Intensive blood glucose control has been shown to help prevent CAN in people with Type 1 diabetes and may help people with Type 2 diabetes as well. Midodrine is the only drug approved by the Food and Drug Administration for treating orthostatic hypotension, but other agents such as fludrocortisone acetate, erythropoeitin, clonidine, nonselective beta blockers, somatostatin analogs, and pyridostigmine bromide sometimes are used.
People with orthostatic hypotension are advised to avoid sitting up or standing up suddenly; wear compression stockings; avoid medications that aggravate orthostatic hypotension, such as tricyclic antidepressants; eat small, frequent meals; and drink plenty of water.