Serum β2-Microglobulin Predicts Mortality in Peritoneal Dialysis Patients: A Prospective Cohort Study.
OBJECTIVE
β2-Microglobulin (β2-M) is a surrogate marker of middle-molecule uremic toxins and is associated with mortality in chronic hemodialysis patients. However, the impact of serum β2-M levels on mortality in peritoneal dialysis (PD) patients is uncertain. The purpose of this study was to examine the association of serum β2-M levels with all-cause mortality in PD patients.


METHODS
A total of 771 PD patients were selected from the Clinical Research Center registry for end-stage renal disease cohort in Korea. Patients were categorized into 3 groups by tertiles of serum β2-M levels. The primary outcome was all-cause mortality.


RESULTS
The median value of serum β2-M was 23.6 mg/l (interquartile range 14.8-33.4 mg/l), and the median follow-up period was 39 months. The Kaplan-Meier analysis showed that the all-cause mortality rate was significantly different according to tertiles of serum β2-M in PD patients (p=0.03, log-rank). Multivariate Cox proportional analysis showed that the hazards ratio for all-cause mortality was 1.02 (95% CI 1.01-1.04, p=0.006) per 1 mg/l increase in β2-M after adjustment for multiple confounding factors that relate to malnutrition and inflammation marker. However, serum β2-M was not associated with all-cause mortality after adjustment for residual renal clearance.


CONCLUSIONS
These results are supportive of the potential role of the serum β2-M level as a predictor of mortality in PD patients.
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Eun Sil
ES
Koh
Kyungsoo
K
Lee
Su Hyun
SH
Kim
Young Ok
YO
Kim
Dong Chan
DC
Jin
Ho Chul
HC
Song
Euy Jin
EJ
Choi
Yong Lim
YL
Kim
Yon Su
YS
Kim
Shin Wook
SW
Kang
Nam Ho
NH
Kim
Chul Woo
CW
Yang
Yong Kyun
YK
Kim
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009026:Mortality; D015999:Multivariate Analysis; D010530:Peritoneal Dialysis; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D056910:Republic of Korea; D001613:beta 2-Microglobulin / Q000097:blood*
D001613:beta 2-Microglobulin