Continuous subcutaneous insulin infusion therapy (CSII) influences cardiovascular responses to graded exercise in patients with autonomic diabetic neuropathy of the cardiovascular system (ADNCS).

We have demonstrated previously the effect of CSII on diabetics with ADNCS. In this study 16 Type-1-diabetics with ADNCS, 20 diabetics without ADNCS and 20 non diabetic controls were examined. Mean age and mean diabetes duration were similar in all groups. Graded exercise was performed in all patients using an ergometer cycle. In patients with ADNCS resting heart rate was significantly higher. The increase in heart rate during exercise was significantly lower, maximal tolerated work load was significantly reduced, and blood pressure-heart-rate multiplication as indirect measurement of oxygen uptake was significantly reduced too. The 16 diabetics with ADNCS were divided into 2 groups: 6 patients got CSII (12 months), 10 patients continued conventional s.c. therapy. After 6 and after 12 months graded exercise was performed again. The patients on s.c. therapy showed no improvement. 3 of the 6 CSII treated patients showed a significant improvement of the above mentioned parameters. Thus, in diabetics with ADNCS, CSII might not only influence the cardiovascular reflex tests, but might also have an effect on cardiovascular responses to graded exercise.