Some retrospective nonrandomised or cross-sectional studies have shown
that higher blood glucose levels are associated with more pronounced
microvascular complications in patients with insulin-dependent diabete
s mellitus (IDDM). The prospective randomised studies had, until recen
tly, been less definitive. Intensified treatment, and thus lower blood
glucose levels, has led to an initial worsening of retinopathy, but t
his tendency towards more advanced retinopathy has been transient. Alb
uminuria and manifest neuropathy have been retarded to some extent. To
day, 2 long term randomised studies, the Stockholm study and the Diabe
tes Control and Complications Trial (DCCT), have proven that a lowerin
g of mean blood glucose levels, measured as a lower glycosylated haemo
globin (HbA1c) value, retards or halts retinopathy, nephropathy and pe
ripheral neuropathy. Intensified treatment, whether performed with mul
tiple injections or insulin pumps, leads to some weight gain and a 3-f
old increase in the frequency of severe hypoglycaemic episodes. Hypogl
ycaemia did not cause long term reduced cognitive function in either s
tudy, but was unpleasant to the patients. A great majority of patients
in the Stockholm study stated that their well-being had increased whi
le participating in the study. The Stockholm programme required 35 min
utes extra per patient per month, and a physician and a nurse could tu
tor 400 patients. This would bring a significant reduction of serious
complications and a gain in terms of patient discomfort and cost. A pr
ogramme of intensified treatment for IDDM is generally indicated and i
s possible to carry out.