Alkaline phosphatase and mortality in patients on peritoneal dialysis.
OBJECTIVE
Elevated total serum alkaline phosphatase levels have been associated with higher mortality in the general population, CKD patients, and hemodialysis patients. However, in peritoneal dialysis patients, this association has received little attention. The aim of this study was to evaluate the association between alkaline phosphatase and all-cause and cardiovascular mortality in peritoneal dialysis patients.


METHODS
In this single center retrospective cohort study, 1021 incident peritoneal dialysis patients from January 1, 2006, to December 31, 2010 with baseline serum alkaline phosphatase values were enrolled. Collected baseline data included demographic characteristics and clinical and laboratory measurements. All patients were followed until December 31, 2012. The associations of total serum alkaline phosphatase levels with all-cause and cardiovascular mortality were assessed using multivariable-adjusted Cox models.


RESULTS
Of 1021 patients, mean age was 47.5 (± 15.5) years, 59.1% of patients were men, and 22.8% of patients were diabetic. The median serum alkaline phosphatase level was 64 U/L (interquartile range=52-82 U/L). During a median 31-month (interquartile range=19-45 months) follow-up period, 203 patients died, of which 109 deaths were caused by cardiovascular disease. After adjusting for demographics, comorbid conditions, liver function, and bone metabolism parameters, the highest alkaline phosphatase quartile was significantly associated with a hazard ratio for all-cause mortality of 1.70 (95% confidence interval, 1.06 to 2.74, P=0.03) and a hazard ratio for cardiovascular mortality of 1.94 (95% confidence interval, 1.02 to 3.72, P=0.04). Each 10 U/L higher baseline alkaline phosphatase level was associated with 4% (95% confidence interval, 1.00 to 1.08, P=0.04) and 7% (95% confidence interval, 1.02 to 1.11, P=0.003) higher risk of all-cause and cardiovascular mortality, respectively.


CONCLUSIONS
Higher total serum alkaline phosphatase levels at the commencement of peritoneal dialysis were independently associated with all-cause and cardiovascular mortality in peritoneal dialysis patients.
Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health, Guangdong, China.
Xinhui
X
Liu
Qunying
Q
Guo
Xiaoran
X
Feng
Juan
J
Wang
Juan
J
Wu
Haiping
H
Mao
Fengxian
F
Huang
Xueqing
X
Yu
Xiao
X
Yang
D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000201:enzymology / Q000401:mortality; D002423:Cause of Death; D016009:Chi-Square Distribution; D002681:China; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007674:Kidney Diseases / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010530:Peritoneal Dialysis / Q000009:adverse effects / Q000401:mortality*; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D015854:Up-Regulation
D015415:Biomarkers; D000469:Alkaline Phosphatase