Mortality of combined serum phosphorus and parathyroid hormone concentrations and their changes over time in hemodialysis patients.
BACKGROUND
Mineral and bone disorder (MBD) is common and associated with mortality in patients with chronic kidney disease (CKD) Given that disarrays in serum phosphorus (P) and parathyroid hormone (PTH) levels and their changes over time are closely interrelated, modeling mortality-predictability of their combinations may help improve CKD patient management.


METHODS
A historical cohort study was undertaken to evaluate the joint effect of serum P and PTH levels on mortality in 107,299 chronic hemodialysis (HD) patients. Changes in serum P and PTH levels over 6months, in particular discordant changes, were also modeled with mortality.


RESULTS
HD patients were 64±15 (mean±SD)years old and included 45% women, 33% African-American, and 59% diabetic. Compared with serum P level ≥7.0mg/dL and PTH level ≥600pg/mL, adjusted hazard ratio (HR) tended to be lowest in patients with serum P level of 3.5-<5.5mg/dL combined with PTH level of 150-<300pg/mL (HR 0.64, 95% confidence interval 0.61-0.67). A change over time in serum P level towards the 3.5-<5.5mg/dL range from higher or lower ranges was associated with a decreased mortality, whereas only change in PTH level from <150pg/mL to 150-<300pg/mL range was associated with a lower risk of mortality. Upon discordant changes of PTH and P, i.e., decrease in one of the two measures while the other increased, no change in mortality risk was observed.


CONCLUSIONS
In CKD-MBD management, patent survival is the greatest with controlling both serum P and PTH levels in balance. Tailoring an individualized treatment strategy in CKD-MBD may benefit patients. Further studies are needed.
Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine, School of Medicine, Orange, CA, USA.
Elani
E
Streja
Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine, School of Medicine, Orange, CA, USA.
Hsin-Yi
HY
Wang
Division of Nephrology and Hypertension, University of California Irvine, School of Medicine, Orange, CA, USA.
Wei Ling
WL
Lau
Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine, School of Medicine, Orange, CA, USA; Division of Nephrology, University Health Network, University of Toronto, Toronto, ON, Canada.
Miklos Z
MZ
Molnar
Division of Nephrology, Memphis Veterans Affairs Medical Center, Memphis, TN, USA; University of Tennessee Health Science Center, Memphis, TN, USA.
Csaba P
CP
Kovesdy
Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine, School of Medicine, Orange, CA, USA; Division of Nephrology and Hypertension, University of California Irvine, School of Medicine, Orange, CA, USA; Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA, USA. Electronic address: kkz@uci.edu.
Kamyar
K
Kalantar-Zadeh
Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine, School of Medicine, Orange, CA, USA; Division of Nephrology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea. Electronic address: jonghaparkmd@gmail.com.
Jongha
J
Park
D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D010758:Phosphorus / Q000097:blood*; D006435:Renal Dialysis / Q000401:mortality*; D012189:Retrospective Studies
D010281:Parathyroid Hormone; D010758:Phosphorus
Bone; Hemodialysis; Hyperparathyroidism; Mineral; Phosphorus