Elevated serum phosphate predicts mortality in renal transplant recipients

Transplantation. 2009 Apr 15;87(7):1040-4. doi: 10.1097/TP.0b013e31819cd122.


Background: High serum phosphate has been identified as an important contributor to the vascular calcification seen in patients with chronic kidney disease (Block et al., Am J Kidney Dis 1998; 31: 607). In patients on hemodialysis, elevated serum phosphate levels are an independent predictor of mortality (Block et al., Am J Kidney Dis 1998; 31: 607; Block, Curr Opin Nephrol Hypertens 2001; 10: 741). The aim of this study was to investigate whether an elevated serum phosphate level was an independent predictor of mortality in patients with a renal transplant.

Methods: Three hundred seventy-nine asymptomatic renal transplant recipients were recruited between June 2000 and December 2002. Serum phosphate was measured at baseline and prospective follow-up data were collected at a median of 2441 days after enrolment.

Results: Serum phosphate was significantly higher in those renal transplant recipients who died at follow-up when compared with those who were still alive at follow-up (P<0.001). In Kaplan-Meier analysis, serum phosphate concentration was a significant predictor of mortality (P=0.0001). In multivariate Cox regression analysis, serum phosphate concentration remained a statistically significant predictor of all-cause mortality after adjustment for traditional cardiovascular risk factors, estimated glomerular filtration rate, and high sensitivity C reactive protein (P=0.036) and after adjustment for renal graft failure (P=0.001).

Conclusions: The results of this prospective study are the first to show that a higher serum phosphate is a predictor of mortality in patients with a renal transplant and suggest that serum phosphate provides additional, independent, prognostic information to that provided by traditional risk factors in the risk assessment of patients with a renal transplant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers / blood
  • Blood Pressure
  • C-Reactive Protein / metabolism
  • Calcium / blood
  • Follow-Up Studies
  • Glomerular Filtration Rate
  • Humans
  • Hyperphosphatemia / diagnosis
  • Kidney Transplantation / mortality
  • Kidney Transplantation / physiology*
  • Middle Aged
  • Parathyroid Hormone / blood
  • Phosphates / blood*
  • Predictive Value of Tests
  • Prognosis
  • Retrospective Studies
  • Survival Analysis
  • Survivors


  • Biomarkers
  • Parathyroid Hormone
  • Phosphates
  • C-Reactive Protein
  • Calcium