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/1, urinary albumin excretion rate 7.9x/-=-2.0 ug/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.

Key Words:

• [⁵¹CrIEDTA-clearance
• glomerular filtration rate
• glycosylated haemoglobin
• kidney volume
• non-insulin-dependent diabetes
• normoalbuminuria
• urinary albumin excretion rate