Hyperfiltration in patients with type I diabetes mellitus: a prevalence study

Clin Nephrol. 1998 Oct;50(4):214-7.

Abstract

Aim: An increase in glomerular filtration rate (GFR) and renal plasma flow (EFPR) may be considered as prognostic factors for the progression of diabetic nephropathy; however the real predicting value of hyperfiltration in the development of incipient and overt nephropathy is as yet unknown. We have examined the prevalence of hyperfiltration in a population of normotensive adult IDDM patients and the possible effect of long-term metabolic control on glomerular hemodynamics.

Materials and methods: We measured GFR and ERPF values in 177 normotensive, normoalbuminuric insulin-dependent diabetic patients and in 30 healthy subjects by single bolus intravenous injection of 1 miroCu/kg [51Cr]-EDTA and 0.2 microCu/kg [125I]-Hippuran intravenously. We have correlated the GFR values with parameters of metabolic control over the last 3 years and with age, sex, and duration of diabetes.

Results: Patients with a GFR greater than the 95 degrees percentile value of controls (135 ml/min/1,73 m2) were defined as hyperfiltering. They represented the 55.9% (99/177) of our population. We found a strong correlation between GFR and ERPF (p <0.001), and between GFR and average HbA1c levels (p = 0.016) in multiple regression analysis, with age, sex, ERPF, and average HbA1c levels entered as variables (r2 = 0.45). There appeared to be no correlation with the duration of the disease.

Conclusions: Long-term hyperglycemia provides a significant contribution in GFR and a poor metabolic control is predictive of overt nephropathy. In this study hyperfiltration does not appear to be the major factor of diabetic nephropathy. A follow-up of these patients is necessary to clarify the role of hyperfiltration in the development of overt nephropathy in diabetes.

MeSH terms

  • Adult
  • Age Factors
  • Chromium Radioisotopes
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetes Mellitus, Type 1 / physiopathology*
  • Diabetes Mellitus, Type 1 / prevention & control
  • Diabetic Nephropathies / etiology
  • Diabetic Nephropathies / physiopathology
  • Disease Progression
  • Female
  • Follow-Up Studies
  • Forecasting
  • Glomerular Filtration Rate / physiology*
  • Glycated Hemoglobin A / analysis
  • Hemodynamics
  • Humans
  • Hyperglycemia / physiopathology
  • Hyperglycemia / prevention & control
  • Iodine Radioisotopes
  • Kidney Glomerulus / physiopathology
  • Male
  • Prevalence
  • Prognosis
  • Radiopharmaceuticals
  • Regression Analysis
  • Renal Plasma Flow / physiology*
  • Sex Factors
  • Time Factors

Substances

  • Chromium Radioisotopes
  • Glycated Hemoglobin A
  • Iodine Radioisotopes
  • Radiopharmaceuticals