Glomerular filtration rate and kidney volume in normoalbuminuric non-insulin-dependent diabetics-lack of glomerular hyperfiltration and renal hypertrophy in uncomplicated NIDDM

Abstract

Glomerular filtration rate (GFR) and kidney volume were evaluated in 18 healthy normoalbuminuric non-insulin-dependent diabetic patients and compared to 12 healthy controls matched for sex, age and body mass index (BMI). The patients (12 males, six females) were 61.6 .+-. 3.4 (mean .+-. SD) years old, the known diabetes duration was 5 .+-. 4.8 years, fasting plasma glucose 8.6 .+-. 2.3 mmol/l, urinary albumin excretion rate 7.9 .times./.div. 2.0 .mu.g/min, BMI 26.8 .+-. 2.8 kg/m2 and blood pressure systolic/diastolic 145 .+-. 19/82 .+-. 7 mmHg. The GFR was measured by the plasma clearance of [51Cr]EDTA, using a single shot procedure. The kidney volume was measured by ultrasonic scanning. The GFR was not increased in diabetics: 100.4 .+-. 16.7 ml/min/1.73 m2 as compared to controls: 93.8 .+-. 11.4 ml/min/1.73 m2. The kidney volume was similar in the two groups. Diabetics: 231.1 .+-. 33.4 ml/1.73 m2. Controls: 236.3 .+-. 45.7 ml/1.73 m2. There was a borderline significant correlation between kidney volume and GFR (r = 0.40, p = 0.10) in diabetics. No correlation between glycosylated haemoglobin and GFR was found in diabetics. In contrast to the findings in insulin-dependent diabetes renal hypertrophy and hyperfunction were not characteristic features in this series of non-insulin-dependent diabetics. It is suggested that diabetic glomerulopathy is not always a consequence of long-standing hyperfiltration.