Improvement of cardiovascular autonomic reflexes after amelioration of metabolic control in insulin-dependent diabetic subjects with severe autonomic neuropathy.
To evaluate the influence of good metabolic equilibrium on Diabetic Autonomic Neuropathy (DAN), cardiovascular autonomic reflexes were monitored in 9 male insulin-dependent diabetic patients with DAN, treated with Continuous Subcutaneous Insulin Infusion (CSII) by pump: 9 for 10 days, 4 for 1 year and 2 for 20 months. Autonomic neuropathy was assessed evaluating 5 cardiovascular autonomic tests: Valsalva Manoeuvre (VR), Deep Breathing (DB), Lying-to-Standing (L-S), Sustained Handgrip (SHG), and Postural Hypotension (PH). Metabolic control was assessed evaluating the mean daily plasma glucose, glucosuria and glycosylated hemoglobin. Ten days of CSII treatment induced a normalization of glucose balance and a slight but significant improvement in some parasympathetic cardiovascular tests (VR: from 1.09 +/- 0.01 to 1.13 +/- 0.02; P less than 0.05). After 4-8 months of CSII treatment a significant improvement in VR (P less than 0.05); DB (P less than 0.01) and L-S (P less than 0.05) was recorded. The long-term treatment with CSII did not seem to induce a further amelioration in cardiovascular autonomic reflexes. These results show that the slight improvement induced by good metabolic balance in the cardiovascular autonomic response could be related to functional-metabolic rather than structural changes in the nerves.
D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002319:Cardiovascular System / Q000294:innervation* / Q000503:physiopathology; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy*; D003929:Diabetic Neuropathies / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D007332:Insulin Infusion Systems; D008297:Male; D008875:Middle Aged; D012021:Reflex, Abnormal / Q000628:therapy