title: Hyperphosphatemia is associated with overt proteinuria in non-diabetic patients with late-stage chronic kidney disease: a cross-sectional study.
abstract: OBJECTIVE
  Proteinuria plays an important role in the progression of chronic kidney disease (CKD), as well as a powerful predictor of cardiovascular morbidity and mortality. The aim of our study was to investigate the potential determinants associated with overt proteinuria in non-diabetic patients with late-stage CKD.
  
  
  METHODS
  Between January 2006 and September 2011, a total of 418 non-diabetic patients with CKD stage 3-5 were enrolled from the outpatient department of nephrology. Urinary protein-to-creatinine ratio and serum phosphorus were determined. Other laboratory parameters, associated comorbidities, medication use, body mass index, and blood pressure were also assessed.
  
  
  RESULTS
  The mean age of the patients was 66.7 ± 14.0 years. In multiple logistic regression analysis and adjusting for established risk factors, the odds ratios for overt proteinuria were 3.96 (95 % confidence interval, 1.80-8.76; p = 0.001) for higher serum phosphorus level (≥4.3 mg/dl) and 3.56 (95 % confidence interval, 1.47-8.63; p = 0.005) for hypercholesterolemia (≥217 mg/dl), compared to subjects with serum phosphorus <3.3 mg/dl and cholesterol level 158-184 mg/dl. The similar significant findings remained robust in individuals not receiving phosphate binder.
  
  
  CONCLUSIONS
  Hyperphosphatemia and high serum cholesterol are associated with overt proteinuria in non-diabetic patients with late-stage CKD. Further studies should clarify whether this relation is causal and whether serum phosphorus level should be a new therapeutic target for proteinuria reduction.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Yuan's General Hospital, No. 162, Chenggong 1st Rd., LingYa District, Kaohsiung City 802, Taiwan, ROC.
authors.forename: Yit-Sheung
authors.initials: YS
authors.lastname: Yap
authors.forename: Wen-Che
authors.initials: WC
authors.lastname: Chi
authors.forename: Cheng-Hao
authors.initials: CH
authors.lastname: Lin
authors.forename: Yi-Wen
authors.initials: YW
authors.lastname: Wu
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Liu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002784:Cholesterol / Q000097:blood; D016001:Confidence Intervals; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000150:complications* / Q000652:urine; D054559:Hyperphosphatemia / Q000097:blood / Q000150:complications* / Q000652:urine; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000150:complications / Q000652:urine*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010758:Phosphorus / Q000097:blood; D011507:Proteinuria / Q000097:blood / Q000150:complications* / Q000652:urine; D012189:Retrospective Studies
chemical_list: D010758:Phosphorus; D002784:Cholesterol; D003404:Creatinine