Circulating levels of CD34+ cells predict longterm cardiovascular outcomes in patients on maintenance hemodialysis

CD34(+) cells maintain vascular homeostasis and predict cardiovascular outcomes. We previously evaluated the association of CD34(+) cells with cardiovascular disease (CVD) events over 23 months, but long-term CVD outcomes in relation to levels of CD34(+) cells in patients on maintenance hemodialysis are unclear. Herein, we analyzed the long-term predictive potential levels of CD34(+) cells for CVD outcomes and all-cause mortality. Between March 2005 and May 2005, we enrolled 215 patients on maintenance hemodialysis at Nagoya Kyoritsu Hospital and followed them up to 12.8 years. According to the CD34(+) cell counts, patients were classified into the lowest, medium, and highest tertiles. Levels of CD34(+) cells were analyzed in association with four-point major adverse CV events (MACEs), CVD death, and all-cause mortality. In univariate analysis age, smoking habit, lower geriatric nutrition risk index, lower calcium x phosphate product, and lower intact parathyroid hormone were significantly associated with the lowest tertile. Whereas, in multivariate analysis, age and smoking habit were significantly associated with the lowest tertile. Among 139 (64.7%) patients who died during a mean follow-up period of 8.0 years, 39 (28.1%) patients died from CVD. Patients in the lowest tertile had a significantly lower survival rate than those in the medium and highest tertiles (p<0.001). Using multivariable analyses, the lowest tertile was significantly associated with four-point MACEs (hazard ratio 1.80, p = 0.023) and CVD death (hazard ratio 2.50, p = 0.011). In conclusion, our long-term observational study revealed that a low level of CD34(+) cells in the circulation predicts CVD outcomes among patients on maintenance hemodialysis.