1. Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
2. School of Medicine, College of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan
3. Division of Nephrology, Department of Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
4. Division of Nephrology, Department of Internal Medicine, Yonghe Cardinal Tien Hospital, New Taipei City, Taiwan
5. Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, Taiwan
6. Division of Nephrology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University
7. Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
8. Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
9. Department of Medicine, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
* These authors have contributed equally to this work.
Background: The endothelial progenitor cells (EPCs) dysfunction is a critical event in the initiation of atherosclerotic plaque development and the level of circulating EPCs can be considered a biomarker of cardiovascular events. The level and functional change in EPCs has been investigated in hemodialysis patients, but the effect of absolute number of EPCs on risk of death has not yet been explored. We hypothesized that the number of EPCs predicted death from cardiovascular and all-cause mortality in hemodialysis patients.
Methods: We evaluate the association between endothelial progenitor cells and clinical outcome in 154 patients on maintenance hemodialysis. The blood sample was drawn at the time of patient enrollment and EPCs were identified by flow cytometry using triple staining for CD34/CD133/KDR.
Results: The median duration of follow-up was 4.19 years. There were 79 (51.3%) deaths during the follow-up period, 41 of whom died due to a confirmed cardiovascular cause. The cumulative survival was greater in the high-EPC group than the low-EPC group for all-cause and cardiovascular mortality. Decreased EPCs levels were associated with a significant increase in the risk of cardiovascular and all-cause mortality after adjusting for age, gender, current smokers, diabetes mellitus, and hypertension.
Conclusions: The level of circulating EPCs independently predicts the clinical outcome in patients on maintenance hemodialysis. Thus, the EPCs levels may be a useful predictive tool for evaluating the risk of death in maintenance hemodialysis patients.
Keywords: endothelial progenitor cells, hemodialysis, mortality