title: 25-Hydroxyvitamin D levels and chronic kidney disease in the AusDiab (Australian Diabetes, Obesity and Lifestyle) study.
abstract: BACKGROUND
  Low 25-hydroxy vitamin D (25(OH)D) levels have been associated with an increased risk of albuminuria, however an association with glomerular filtration rate (GFR) is not clear. We explored the relationship between 25(OH)D levels and prevalent chronic kidney disease (CKD), albuminuria and impaired GFR, in a national, population-based cohort of Australian adults (AusDiab Study).
  
  
  METHODS
  10,732 adults ≥ 25 years of age participating in the baseline survey of the AusDiab study (1999-2000) were included. The GFR was estimated using an enzymatic creatinine assay and the CKD-EPI equation, with CKD defined as eGFR <60 ml/min/1.73 m(2). Albuminuria was defined as a spot urine albumin to creatinine ratio (ACR) of ≥ 2.5 mg/mmol for men and ≥ 3.5 for women. Serum 25(OH)D levels of <50 nmol/L were considered vitamin D deficient. The associations between 25(OH)D level, albuminuria and impaired eGFR were estimated using multivariate regression models.
  
  
  RESULTS
  30.7% of the study population had a 25(OH)D level <50 nmol/L (95% CI 25.6-35.8). 25(OH)D deficiency was significantly associated with an impaired eGFR in the univariate model (OR 1.52, 95% CI 1.07-2.17), but not in the multivariate model (OR 0.95, 95% CI 0.67-1.35). 25(OH)D deficiency was significantly associated with albuminuria in the univariate (OR 2.05, 95% CI 1.58-2.67) and multivariate models (OR 1.54, 95% CI 1.14-2.07).
  
  
  CONCLUSIONS
  Vitamin D deficiency is common in this population, and 25(OH)D levels of <50 nmol/L were independently associated with albuminuria, but not with impaired eGFR. These associations warrant further exploration in prospective and interventional studies.
authors: Department of Nephrology, Monash Medical Centre, 246 Clayton Road, Clayton, 3168, Victoria, Australia. matthew.damasiewicz@monash.edu
authors: Matthew J
authors: MJ
authors: Damasiewicz
authors: Dianna J
authors: DJ
authors: Magliano
authors: Robin M
authors: RM
authors: Daly
authors: Claudia
authors: C
authors: Gagnon
authors: Zhong X
authors: ZX
authors: Lu
authors: Peter R
authors: PR
authors: Ebeling
authors: Steven J
authors: SJ
authors: Chadban
authors: Robert C
authors: RC
authors: Atkins
authors: Peter G
authors: PG
authors: Kerr
authors: Jonathan E
authors: JE
authors: Shaw
authors: Kevan R
authors: KR
authors: Polkinghorne
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000097:blood / Q000453:epidemiology; D001315:Australia / Q000453:epidemiology; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D014807:Vitamin D; C104450:25-hydroxyvitamin D