FC 108BASELINE AND CORONARY ARTERY CALCIFICATION PROGRESSION MODULATES THE RISK OF DEATH IN INCIDENT TO DIALYSIS PATIENTS

Abstract

Abstract Background and Aims It is estimated that Chronic Kidney Disease (CKD) accounts for 5 to 10 million deaths annually, mainly due to cardiovascular (CV) diseases. Although traditional CV risk factors are prevalent, other non-traditional CV risk factors such as vascular calcification (VC) are believed to contribute to this disproportionate CV risk burden in CKD subjects. We sought to investigate the association of Coronary Artery Calcification (CAC) progression with all-cause mortality in a cohort of patients new to hemodialysis (HD). Method This is a post hoc analysis of the Independent study (NCT00710788) originally designed to test the impact of 2 different phosphate binder regimens on various hard as well as surrogate endpoint in HD subjects. A total of 412 (88.4% of the Independent study cohort) underwent repeated CAC quantification according to the Agatston methods at study inception as well as after 12 months of follow-up. The square root method was used to assess CAC progression (CACP) and survival analyses were used to check the association of CACP and all-cause mortality. Results 412 middle age (65 years) men and women (51.2%) were considered. Detectable CAC was present in about 2 out 3 patients (68.2%) at study inception. At 12 months of follow-up completion, about 1 out of 3 subjects (33.1%) experience a significant CACP. CACP was associated with older age and use of calcium-based phosphate binders. At study completion (median follow-up: 36 months) 106 patients expired of all-cause. Age, diabetes mellitus, atherosclerotic CV events, baseline CAC extension were predictors of unfavorable outcome. Multivariable adjusted analysis confirmed an independent association of both baseline CAC (Hazard Ratio 1.29; 95% Confidence Interval: 1.17-1.44) and CACP (HR: 5.16; 95%CI: 2.61-10.21) with all-cause mortality. However, CACP diminished the risk associated with baseline CAC (p for interaction term 0.002) and use of calcium-free phosphate binders significantly weakened the link between CACP (HR. 1.95; 95%CI: 0.92-4.16) and mortality Conclusion Baseline CAC as well as CACP predict mortality in incident to HD individuals. Nevertheless, CACP mitigates the risk associated with baseline CAC and calcium-free phosphate binders attenuates the association of CACP and mortality, suggesting that CACP modulation may impact survival in this population