Improvement of mineral and bone metabolism markers is associated with better survival in haemodialysis patients: the COSMOS study.
BACKGROUND
Abnormalities in serum phosphorus, calcium and parathyroid hormone (PTH) have been associated with poor survival in haemodialysis patients. This COSMOS (Current management Of Secondary hyperparathyroidism: a Multicentre Observational Study) analysis assesses the association of high and low serum phosphorus, calcium and PTH with a relative risk of mortality. Furthermore, the impact of changes in these parameters on the relative risk of mortality throughout the 3-year follow-up has been investigated.


METHODS
COSMOS is a 3-year, multicentre, open-cohort, prospective study carried out in 6797 adult chronic haemodialysis patients randomly selected from 20 European countries.


RESULTS
Using Cox proportional hazard regression models and penalized splines analysis, it was found that both high and low serum phosphorus, calcium and PTH were associated with a higher risk of mortality. The serum values associated with the minimum relative risk of mortality were 4.4 mg/dL for serum phosphorus, 8.8 mg/dL for serum calcium and 398 pg/mL for serum PTH. The lowest mortality risk ranges obtained using as base the previous values were 3.6-5.2 mg/dL for serum phosphorus, 7.9-9.5 mg/dL for serum calcium and 168-674 pg/mL for serum PTH. Decreases in serum phosphorus and calcium and increases in serum PTH in patients with baseline values of >5.2 mg/dL (phosphorus), >9.5 mg/dL (calcium) and <168 pg/mL (PTH), respectively, were associated with improved survival.


CONCLUSIONS
COSMOS provides evidence of the association of serum phosphorus, calcium and PTH and mortality, and suggests survival benefits of controlling chronic kidney disease-mineral and bone disorder biochemical parameters in CKD5D patients.
Bone and Mineral Research Unit, Instituto Reina Sofía de Investigación, REDinREN del ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Asturias, Spain.
José Luis
JL
Fernández-Martín
Oficina de Investigación Biosanitaria de Asturias (OIB), Asturias, Spain Universidad Autónoma de Chile, Chile.
Pablo
P
Martínez-Camblor
Bone and Mineral Research Unit, Instituto Reina Sofía de Investigación, REDinREN del ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Asturias, Spain.
María Paula
MP
Dionisi
Department of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany.
Jürgen
J
Floege
Division of Nephrology, Klinikum Coburg, Coburg, Germany.
Markus
M
Ketteler
Centre Hospitalier FH Manhes, France.
Gérard
G
London
Department of Nephrology, Dialysis and Renal Transplant, Alessandro Manzoni Hospital, Lecco, Italy.
Francesco
F
Locatelli
Hospital Universitario Dr. Peset, Valencia, Spain.
José Luis
JL
Gorriz
Department of Nephrology, Transplantology and Internal Medicine, Gdañsk Medical University, Gdansk, Poland.
Boleslaw
B
Rutkowski
Nephrology Department, Hospital Curry Cabral and Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal.
Aníbal
A
Ferreira
Department of Internal Medicine, St. Antonius Hospital, Nieuwegein, The Netherlands.
Willem-Jan
WJ
Bos
University of Medicine 'Gr. T. Popa', Iasi, Romania.
Adrian
A
Covic
Department of Nephrology, Instituto Reina Sofía de Investigación, REDinREN del ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Asturias, Spain.
Minerva
M
Rodríguez-García
Department of Nephrology, Instituto Reina Sofía de Investigación, REDinREN del ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Asturias, Spain.
José Emilio
JE
Sánchez
Department of Medicine, Universidad de Alcalá Nephrology Section and Research Unit Foundation, Hospital Universitario Príncipe de Asturias, Alcalá de Henares, Spain IRSIN REDinREN (Instituto de Salud Carlos III), Madrid, Spain.
Diego
D
Rodríguez-Puyol
Bone and Mineral Research Unit, Instituto Reina Sofía de Investigación, REDinREN del ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Asturias, Spain.
Jorge B
JB
Cannata-Andia
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015415:Biomarkers / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000097:blood; D005060:Europe / Q000453:epidemiology; D005500:Follow-Up Studies; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000401:mortality; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis / Q000401:mortality; D051436:Renal Insufficiency, Chronic / Q000628:therapy; D015996:Survival Rate
D015415:Biomarkers; D002118:Calcium; D010281:Parathyroid Hormone; D010758:Phosphorus
CKD-MBD; PTH; calcium; chronic kidney disease; cosmos; hemodialysis; phosphorous; survival