Third-generation parathyroid hormone assays and all-cause mortality in incident dialysis patients: The CHOICE study

Michal L. Melamed, Joseph A. Eustace, Laura C. Plantinga, Bernard G. Jaar, Nancy E. Fink, Rulan S. Parekh, Josef Coresh, Zan Yang, Tom Cantor, Neil R. Powe

Research output: Contribution to journalArticlepeer-review

52 Scopus citations


Background. There has been controversy about the utility of new third-generation parathyroid hormone (PTH) assays measuring only 1-84 PTH, with few large studies comparing second- and third-generation PTH measurements in patients with ESRD. Methods. We measured 1-84 PTH ('biointact' or 'whole' PTH) and total PTH ('intact' PTH) in a national cohort of 515 incident dialysis patients from banked frozen EDTA plasma (median follow-up, 35 months) and examined the accuracy of estimating 1-84 PTH from total PTH and the associations of these levels with patient characteristics and mortality. Results. The 1-84 PTH and total PTH levels were closely correlated. Higher 1-84 PTH was associated with African-American race and higher serum phosphate and lower calcium levels. The percentage of total PTH represented by 1-84 PTH was, on average, 53%, but with a wide range (25-89%). Calculating 1-84 PTH from total PTH using a proposed standard conversion factor (54%) led to misclassification of 8% of the population compared with measured 1-84 PTH. In a multivariate Cox proportional hazards model for all-cause mortality, a 1-84 PTH value >160 pg/ml was associated with increased risk of mortality (HR = 1.62, 95% CI, 1.03-2.54) compared to a level of 80-160 pg/ml. Elevated total PTH, 7-84 PTH and the 1-84 PTH/7-84 PTH ratio were not significantly associated with mortality. Conclusions. The 1-84 PTH and total PTH are highly correlated. Elevated 1-84 PTH was significantly associated with increased mortality, whereas total PTH did not reach statistical significance. Thus, although in other respect they are similar, there may be utility in measuring 1-84 PTH for its associations with mortality.

Original languageEnglish (US)
Pages (from-to)1650-1658
Number of pages9
JournalNephrology Dialysis Transplantation
Issue number5
StatePublished - May 2008


  • Clinical epidemiology
  • Hyperparathyroidism
  • Mortality risk
  • PTH assays
  • Parathyroid hormone

ASJC Scopus subject areas

  • Nephrology
  • Transplantation


Dive into the research topics of 'Third-generation parathyroid hormone assays and all-cause mortality in incident dialysis patients: The CHOICE study'. Together they form a unique fingerprint.

Cite this