title: Serum phosphorus predicts incident chronic kidney disease and end-stage renal disease.
abstract: BACKGROUND
  Elevations in serum phosphorus are associated with renal decline in animal models and progression of established chronic kidney disease (CKD) in human observational studies. We examined whether serum phosphorus levels increase the risk of incident CKD or end-stage renal disease (ESRD) in two population-based prospective cohort studies.
  
  
  METHODS
  Overall, 2269 participants free of CKD [estimated glomerular filtration rate (eGFR) <60 mL/min/1.73(2)] from the Framingham Heart Study (FHS; mean age 42 years; 53% women) and 13,372 participants from the Third National Health and Nutrition Examination Survey (NHANES III; mean age 44.3 years, 52% women) contributed to the present study. In the FHS, we evaluated the relationship between baseline phosphorus category (<2.5 mg/dL, 2.5-3.49 mg/dL, 3.5-3.99 mg/dL and ≥4 mg/dL) and incident CKD (n = 267). In NHANES, we examined the relationship between phosphorus below and above 4 mg/dL in relation to incident ESRD (n = 65).
  
  
  RESULTS
  FHS participants in the highest phosphorus category had an increased risk of CKD [odds ratio 2.14; 95% confidence interval (CI), 1.07-4.28; P = 0.03] in multivariable-adjusted models when compared to the referent group (2.5-3.49 mg/dL). Similarly, NHANES III participants with phosphorus levels ≥4 mg/dL demonstrated an increased risk of incident ESRD compared to those <4 mg/dL (relative risk 1.90; 95% CI 1.03-3.53; P = 0.04).
  
  
  CONCLUSIONS
  In prospective studies of the general population, serum phosphorus levels in the upper-normal range were associated with a doubling in the risk of developing incident CKD and ESRD.
authors.affiliation: National Heart, Lung and Blood Institute’s Framingham Heart Study and the Center for Population Studies, Framingham, MA, USA.
authors.forename: Conall M
authors.initials: CM
authors.lastname: O'Seaghdha
authors.forename: Shih-Jen
authors.initials: SJ
authors.lastname: Hwang
authors.forename: Paul
authors.initials: P
authors.lastname: Muntner
authors.forename: Michal L
authors.initials: ML
authors.lastname: Melamed
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Fox
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D010758:Phosphorus / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
chemical_list: D010758:Phosphorus