title: Glomerular hyperfiltration and increased proximal sodium reabsorption in subjects with type 2 diabetes or impaired fasting glucose in a population of the African region.
abstract: BACKGROUND. Glomerular hyperfiltration (GHF) is a well-recognized early renal alteration in diabetic patients. As the prevalence of GHF is largely unknown in populations in the African region with respect to normal fasting glucose (NFG), impaired fasting glucose (IFG) and type 2 diabetes [diabetes mellitus (DM)], we conducted a cross-sectional study in the Seychelles islands among families including at least one member with hypertension. METHODS. The glomerular filtration rate (GFR), effective renal plasma flow (ERPF) and proximal tubular sodium reabsorption were measured using inulin, p-aminohippurate (PAH) and endogenous lithium clearance, respectively. Twenty-four-hour urine was collected on the preceding day. RESULTS. Of the 363 participants (mean age 44.7 years), 6.6% had IFG, 9.9% had DM and 63.3% had hypertension. The prevalence of GHF, defined as a GFR >140 ml/min, was 17.2%, 29.2% and 52.8% in NFG, IFG and DM, respectively (P trend <0.001). Compared to NFG, the adjusted odds ratio for GHF was 1.99 [95% confidence interval (CI) 0.73-5.44] for IFG and 5.88 (2.39-14.45) for DM. Lithium clearance and fractional excretion of lithium were lower in DM and IFG than NFG (P < 0.001). CONCLUSION. In this population of African descent, subjects with impaired fasting glucose or type 2 diabetes had a high prevalence of GHF and enhanced proximal sodium reabsorption. These findings provide further insight on the elevated incidence of nephropathy reported among African diabetic individuals.
authors.affiliation: Service of Nephrology, University Hospital of Lausanne (CHUV), Switzerland.
authors.forename: Menno
authors.initials: M
authors.lastname: Pruijm
authors.forename: Grégoire
authors.initials: G
authors.lastname: Wuerzner
authors.forename: Marc
authors.initials: M
authors.lastname: Maillard
authors.forename: Pascal
authors.initials: P
authors.lastname: Bovet
authors.forename: Claude
authors.initials: C
authors.lastname: Renaud
authors.forename: Murielle
authors.initials: M
authors.lastname: Bochud
authors.forename: Michel
authors.initials: M
authors.lastname: Burnier
mesh_terms: D000042:Absorption / Q000502:physiology; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000378:metabolism / Q000503:physiopathology; D005215:Fasting / Q000502:physiology*; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000378:metabolism / Q000503:physiopathology; D007444:Inulin / Q000652:urine; D007687:Kidney Tubules, Proximal / Q000503:physiopathology*; D008094:Lithium / Q000652:urine; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012750:Seychelles; D012964:Sodium / Q000378:metabolism*; D010130:p-Aminohippuric Acid / Q000652:urine
chemical_list: D001786:Blood Glucose; D007444:Inulin; D008094:Lithium; D012964:Sodium; D010130:p-Aminohippuric Acid