Diabetes Care, Vol 8, Issue 6 585-589, Copyright © 1985 by American Diabetes Association
Effect of insulin pump treatment for one year on renal function and retinal morphology in patients with IDDM
H Beck-Nielsen, B Richelsen, CE Mogensen, T Olsen, N Ehlers, CB Nielsen and P Charles
The effect of strict metabolic control for 1 yr on renal function and
retinal morphology was estimated in 24 insulin-dependent diabetic
individuals (age 29 +/- 8 yr, diabetes duration 10 +/- 6 yr) with Albustix
negative urine and minimal or no background retinopathy before the study.
They were randomized to conventional insulin treatment (CIT) or continuous
subcutaneous insulin infusion (CSII) with a portable pump. During CSII
treatment the metabolic status was significantly improved and glomerular
filtration rates (GFR) were found to decline (from 130 +/- 18 to 116 +/- 15
ml/min/1.73 m2, P less than 0.01). The mean value of urinary albumin
excretion (UAE) was not statistically significantly reduced (from 15.3 +/-
24.1 to 6.8 +/- 1.5 mg/24 h, P greater than 0.1). In the CIT group both GFR
and UAE values were unchanged. In all subjects before treatment we found a
positive correlation between the metabolic status, estimated by the HbA1c
values, and GFR as well as UAE values, respectively (r = 0.64, P less than
0.01 and r = 0.42, P less than 0.05). We conclude that elevated GFR values
can be reduced toward normal level by insulin pump treatment for 1 yr.
Retinal morphology was found to deteriorate in four of 12 CIT subjects and
in three of 12 CSII subjects. However, the progression was mild and in most
individuals only due to a slight increase in the number of microaneurysms.
Pump treatment did not induce proliferation and "cotton-wool" exudates were
not detectable in any pump subject after 1 yr of treatment. We conclude
that CSII treatment for 1 yr was unable to stop the progression of
retinopathy in individuals with minimal or no retinopathy on entering the
study. On the other hand, pump treatment did not induce cotton-wool
exudates or proliferation in these subjects as previously reported in
subjects with more severe retinopathy before CSII treatment.