Relationship between coronary artery calcification and outcomes in maintenance hemodialysis patients

Abstract

Objective To evaluate the relationship between coronary artery calcification (CAC) and outcomes in maintenance hemodialysis (MHD) patients. Methods Eighty-six patients who were on MHD between October 2014 and May 2015 in the blood purification center of our hospital were enrolled prospectively. CAC was measured and scored by multiple slice computed tomography (MSCT). According to the CAC score (CACs), the patients were divided into mild CAC (CACs<100) group and severe CAC (CACs≥100) group. Kaplan-Meier analysis was performed to analyze the survival rates of the two groups, and a COX proportional hazards regression model was used to estimate the risk factors of all-cause mortality and cardiovascular disease mortality in MHD patients. Results Severe CAC (CACs≥100) was present in 62.8% (54/86) patients. The median of follow-up duration was 28.9(23.8, 29.4) months. During the follow up, 2(6.3%) patients in CACs<100 group and 18 (33.3%) patients in CACs≥100 group died. Kaplan-Meier survival analysis demonstrated that patients in CACs≥100 group had higher all-cause mortality and cardiovascular mortality as compared with patients in CACs<100 group (P=0.007, P=0.030). Multivariate COX regression analysis demonstrated that CACs≥100 (HR=7.687, 95% CI 1.697-34.819, P=0.008) and low single-pool Kt/V (HR=0.092, 95% CI 0.020-0.421, P=0.002) were independent risk factors for all-cause mortality. Old age (HR=1.192, 95%CI 1.100-1.291, P<0.001), short duration of dialysis (HR=0.598, 95%CI 0.445-0.804, P=0.001), low 25-hydroxy vitamin D3 (HR=0.461, 95% CI 0.326-0.630, P<0.001), and low total cholesterol (HR=0.405, 95%CI 0.213-0.772, P=0.006) were independent risk factors for cardiovascular disease mortality. Conclusions The CACs is significantly related with overall survival in MHD patients. Large multicenter prospective studies are to be evaluated the association between CACs and long-term survival in MHD patients. Key words: Renal dialysis; Calcinosis; Renal insufficiency, chronic; Mortality; Vascular calcification; Coronary artery calcification