The Kidney Disease Outcomes Quality Initiative (K/DOQI) Guideline for Bone Metabolism and Disease in CKD: association with mortality in dialysis patients.
BACKGROUND
In 2003, the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (K/DOQI) published a guideline recommending tight control of serum calcium, phosphorus, calcium-phosphorus product (Ca x P), and intact parathyroid hormone levels in patients with chronic kidney disease. Within the context of this guideline, we explored associations of these plasma concentrations with all-cause mortality risk in incident dialysis patients in The Netherlands.


METHODS
In a large, prospective, multicenter, cohort study (Netherlands Cooperative Study on the Adequacy of Dialysis), we included 1,629 patients new on hemodialysis or peritoneal dialysis therapy between 1997 and 2004. Multivariate Cox regression models containing calcium level, phosphorus level, intact parathyroid hormone level, age, comorbidity, primary kidney disease, nutritional status, albumin level, dialysis dose, and hemoglobin level were used to examine mortality risks.


RESULTS
Mean age was 60 +/- 15 (SD) years, 61% were men, and 64% were treated with hemodialysis. In adjusted time-dependent survival analysis, all-cause mortality risk increased in hemodialysis patients by 40% (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.1 to 1.7) and in peritoneal dialysis patients by 60% (HR, 1.6; 95% CI, 1.1 to 2.4) for plasma phosphorus levels greater than the target. In addition, having elevated plasma Ca x P product levels increased mortality risk by 40% (HR, 1.4; 95% CI, 1.1 to 1.8) in hemodialysis patients and 50% in peritoneal dialysis patients (HR, 1.5; 95% CI, 1.0 to 2.2). In both patient groups, no significant effects were observed for plasma levels less than the targets.


CONCLUSIONS
In time-dependent survival analysis, the presence of plasma phosphorus and Ca x P product concentrations greater than K/DOQI targets increased all-cause mortality risk in hemodialysis and peritoneal dialysis patients.
Noordzij
Marlies
M
Department of Clinical Epidemiology, Academic Medical Center, University of Amsterdam, The Netherlands. m.noordzij@amc.uva.nl
Korevaar
Johanna C
JC
Boeschoten
Elisabeth W
EW
Dekker
Friedo W
FW
Bos
Willem J
WJ
Krediet
Raymond T
RT
D000368:Aged; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000097:blood*; D019090:Case Management; D002423:Cause of Death; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000209:etiology / Q000517:prevention & control; D015331:Cohort Studies; D005260:Female; D006040:Goals; D019983:Guideline Adherence; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009426:Netherlands / Q000453:epidemiology; D010281:Parathyroid Hormone / Q000097:blood*; D010530:Peritoneal Dialysis / Q000706:statistics & numerical data*; D010758:Phosphorus / Q000097:blood*; D017410:Practice Guidelines as Topic; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis / Q000706:statistics & numerical data*; D012306:Risk; D016019:Survival Analysis; D013997:Time Factors
D010281:Parathyroid Hormone; D010758:Phosphorus; D002118:Calcium