CAC Score Predicts Cardiac Events in CKD Patients
Assessment of coronary artery calcification (CAC) and progression may be useful for earlier management of risk factors for cardiac events in patients with chronic kidney disease (CKD), according to an Italian study.
Domenico Russo, MD, of the University of Naples, Naples, Italy, and his colleagues studied consecutive non-dialyzed CKD patients who were followed for a mean of 745 days (range 403-1,078 days). The extent of coronary calcifications was associated with cardiac events and calcification progression was an independent predictive factor of cardiac events.
The researchers, who published their findings online in Kidney International, determined subjects' CAC score in Agatston units using computed tomography. They stratified patients into two groups according to baseline calcium score (100 U or less and over 100 U). The investigators measured survival by baseline CAC score and its progression.
After adjusting for age, diabetes, glomerular filtration rate, and hypertension, they found that a baseline CAC score greater than 100 U significantly predicted cardiac events. During the observation time, 29 patients (16%) experienced a cardiac event (cardiac death or myocardial infarction) and these events were four times more likely to occur in patients with CAC scores above 100 U than in patients with lower scores.
Subjects with CAC score of 100 U or less who did not have progression had a 59% decreased risk of cardiac events. However, the hazard ratio was 3.26 in patients with accelerated progression.
The findings confirm that the process leading to CAC and progression is already acting at early stages of CKD. The researchers noted that the cardiac events occurred even in patients with CAC scores consistent with a low mortality risk, suggesting that CKD patients are even more susceptible to the effects of CAC.