Aortic calcification predicts cardiovascular events and all-cause mortality in renal transplantation.

BACKGROUND Cardiovascular disease is a leading cause of death among renal transplant recipients. Aortic calcification is associated with increased mortality in dialysis subjects. The significance of aortic calcification among renal transplant recipients is unknown. Our objective was to prospectively examine the association of aortic calcification with cardiovascular events and all-cause mortality among asymptomatic incident renal transplant recipients. METHODS One hundred and twelve renal transplant recipients underwent electron beam computed tomography. Aortic calcification was scored by the Agatston method. The mean follow-up time was 5.1 years. Cardiovascular events (heart failure, coronary artery disease, peripheral arterial disease and stroke) and all-cause mortality were recorded. RESULTS The cohort consisted of 62% Caucasians, 38% African Americans and 62% male gender. The mean age was 49.0 +/- 12.5 years. Thirty-four percent had aortic calcification. During follow-up, 12 cardiovascular events and 10 deaths were recorded. Subjects with aortic calcification had more cardiovascular events compared to those without aortic calcification (23.7 versus 4.1%, P = 0.001). Recipients with aortic calcification had higher mortality compared to those without aortic calcification but it did not reach statistical significance (15.8 versus 5.4%, P = 0.07). The univariate hazard ratio of aortic calcification score in a proportional hazard Cox model to assess event-free survival was 1.15 (1.04-1.27, P = 0.01). Diabetes and aortic calcification score were independently associated with survival. In addition to the predictors above, dialysis vintage was an independent predictor for combined future cardiovascular event and mortality. CONCLUSIONS In conclusion, aortic calcification is prevalent among renal transplant recipients and is predictive of future cardiovascular events. Aortic calcification is easily identified by non-invasive testing, and should be considered when assessing cardiovascular risk in asymptomatic renal transplant recipients.