Effect of metabolic control on autonomic function in obese patients with newly diagnosed type 2 diabetes

To evaluate the effect of diet therapy and physical exercise on autonomic nervous function in newly diagnosed Type 2 diabetes, we followed 83 middle-aged obese patients (48 men, 35 women) for a 15-month period. After a 3-month basic education programme the patients were randomized to one of two groups for comparison of standard treatment given by community health centres (conventionally treated group) and intensive dietary and exercise education (intervention group). Autonomic function was assessed by heart rate variability during deep breathing (expiration/inspiration ratio, E/I), and by systolic blood pressure response to standing up. The intensively treated women (n = 18) had the best blood glucose throughout the study, and this was the only group to show an improvement in E/I ratio (1.19 +/- 0.03 vs 1.30 +/- 0.05, mean +/- SEM, p < 0.05). None of the groups showed any significant change in systolic blood pressure response to standing up. For further analyses, the original groups were combined and thereafter divided into those with declining fasting blood glucose during the intervention phase (n = 39) and into those with no change or increase in blood glucose level (n = 44). The group with improving blood glucose level showed an increase in E/I ratio (1.22 +/- 0.02 vs 1.28 +/- 0.03, p < 0.01) while in the other group E/I ratio remained unchanged (1.21 +/- 0.02 vs 1.20 +/- 0.02). The difference in E/I ratio between these two groups was significant at 15 months (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)