Impact of arterial microcalcification of the vascular access on cardiovascular mortality in hemodialysis patients

Gross vascular calcification seen on imaging studies is common in hemodialysis (HD) patients, and is a significant predictor for cardiovascular mortality in HD patients. We have reported that arterial microcalcification (AMiC) of the vascular access is associated with increased aortic stiffness. This study investigated the impact of vascular access AMiC on cardiovascular mortality in HD patients. The study included 149 HD patients (mean age: 59.1±13.9 years, 86 men and 63 women, 65.8% diabetic) who underwent vascular access surgery. Radial or brachial artery specimens were obtained intraoperatively, and pathologic examination was performed using von Kossa stain to identify AMiC. We compared all-cause and cardiovascular mortality between patients with and without AMiC. The mean follow-up was 37.8±34.5 months, and AMiC was present in 38.8% (n=57) of patients. The presence of diabetes (odds ratio: 16.49, 95% confidence interval: 1.81-150.36, P=0.013) was the only independent risk factor for vascular access AMiC. During the observational period, there were 27 cardiovascular deaths. Kaplan-Meier analysis showed an increased cardiovascular mortality risk (log rank=4.83, P=0.028) in AMiC patients, and Cox regression analysis confirmed that AMiC was an independent predictor for cardiovascular mortality (hazard ratio: 2.35, 95% confidence interval: 1.09-5.09, P=0.030). In conclusion, vascular access AMiC is a strong risk factor for cardiovascular mortality in HD patients.