In extremely unstable (brittle) IDDM patients (n = 11) the metabolic effect of long-term (36 months) CSII proved to be superior to conventional insulin treatment (CIT) (statistical twins, n = 11): HbA1 = 8.6 +/- 0.3 versus 10.4 +/- 0.4, MBG = 5.6 +/- 0.3 versus 8.5 +/- 0.8, M (80)- value = 23.6 +/- 0.6 versus 56.7 +/- 10.2, GCI) = 37.3 +/- 15.6 versus 132 +/- 24.2. In addition, in CSII patients the metabolic control was significantly better than intensified conventional insulin treatment (ICT) before. Retinal morphology improved under CSII in 1 eye, did not change in 10 eyes and deteriorated in 11 eyes. Under CIT retinal findings improved in none, did not change in 16 and deteriorated in 16 eyes. Deteriorations under CSII appeared more frequently during the first than during the second and third year of treatment and seemed to be a consequence of too strict metabolic control and/or too fast decrease of the glycemia at the beginning of CSII. During 36 months of CSII no deterioration but in one case normalization of microproteinuria was observed. Under CIT three cases changed from normal into microproteinuria. Reduced motor nerve conduction velocity (MCV) and/or sensory nerve conduction velocity (SCV) could be normalized in most cases under CSII, but respiratory heart arrhythmia (RHA) at rest could not. Most patients--if highly motivated before starting CSII--remained positively motivated for long-term pump therapy.
In conclusion: Our experiences over three years demonstrate a positive effect of CSII on the metabolism as well as on the course of early stages of microangiopathy and neuropathy. A longer period of observations will be necessary to evaluate this, conclusively.