The significance of autonomic symptoms in Nigerian diabetics.

Diabetes mellitus is the most common endocrine disorder worldwide and disturbance of autonomic function is a frequent complication. Symptoms of autonomic neuropathy are however non-specific and the aetiology is multifactorial in diabetics. This study was carried out to determine the relationship between symptoms of autonomic neuropathy and pathology of the autonomic nervous system in diabetic patients. A hundred diabetics were studied, 50 with, and 50 without symptoms of autonomic neuropathy. Objective test of autonomic function used were the heart rate responses to deep breathing, to standing and to the Valsava manoeuvre; and the blood pressure responses to standing and to sustained handgrip. There was no significant difference between diabetics with symptoms suggestive of autonomic neuropathy, and those without, with regard to findings on autonomic function testing. While the symptoms were unreliable in determining the presence of autonomic neuropathy, they were significantly related to poor glycaemic control and to peripheral neuropathy (P < 0.01). The symptoms of autonomic neuropathy are non-specific in Nigerian diabetics and may reflect poor glycaemic control rather than autonomic neuropathy. Autonomic function tests should be carried out in diabetics suspected of having autonomic neuropathy.