ALBUMIN EXCRETION RATE, SERUM INSULIN-LIKE GROWTH-FACTOR-I AND GLOMERULAR-FILTRATION RATE IN TYPE-I DIABETES-MELLITUS AT PUBERTY

The albumin excretion rate (AER), insulin-like growth factor-I (IGF-I) levels, glomerular filtration rate (GFR) and glycosylated hemoglobin (HbA(1c)) levels were studied in 49 diabetic children and 49 controls, The duration of diabetes varied from newly diagnosed to 17.5 years, D iabetics exhibited a wide range of AER values and had significantly hi gher AER and IGF-I levels compared to controls, At puberty elevated ci rculating growth hormone (GH) concentrations were found with a paralle l increase in the levels of IGF-I. High IGF-I levels were found in 10- 12 year-old girls and 15-16 year-old boys in both diabetic and control groups, Positive correlations were found between IGF-I and GFR in gir ls of both groups (p<0.05) and in control girls between IGF-I, GFR and microalbuminuria (p<0.05), The diabetic boys also showed microalbumin uria with respect to controls at high HbA(1c) levels and when their te stis volume exceeded 8 ml (p<0.05), We concluded that the prominent ch ange in GH release at puberty, reflected by IGF-I, is in pulse amplitu de, and that this is increased in diabetes but it is not a very import ant factor when determining the abnormal levels of urinary albumin exc retion.