Hemodialysis Patient Death Risk Linked to CAC on Chest X-Rays
Coronary artery and aortic arch calcification are highly prevalent on chest radiographs of hemodialysis (HD) patients and each is independently and strongly associated with increased mortality risk, according to a study.
“Because these images are nearly ubiquitous, inexpensive, and often obtained for other indications, they should be considered for risk assessment in hemodialysis patients,” the researchers concluded in a paper published online ahead of print in the American Journal of Kidney Diseases. Coronary artery calcification (CAC) and aortic arch calcification (AAC) “should be mentioned specifically by radiologists in their chest radiographic reports,” they stated.
The study, led by Joseph A. Abdelmalek, MD, and Dena E. Rifkin, MD, MS, of the University of California-San Diego, included 93 patients receiving maintenance HD at the San Diego Veterans Affairs Medical Center. Patients had an average age of 64 years and 97% were men. A radiologist determined the presence of CAC and AAC.
Of the 93 patients, 23 (24.7%) had visible CAC on chest radiographs and 54 (58%) had AAC. During 20 months of follow-up, 26 patients (28%) died. CAC was associated with a significant two- to threefold increase risk of all-cause mortality that was not attenuated after adjusting for standard cardiovascular or dialysis-related risk factors or the presence of AAC, the researchers reported. AAC was associated with a sevenfold increased risk in a fully adjusted model and a sixfold increased risk after adjustment for CAC.
“To our knowledge, this is the first study to show that CAC observed on conventional chest radiography is associated independently with mortality in hemodialysis patients,” the investigators wrote.
The researchers acknowledge some study limitations, including the relatively small patient sample size that consisted mostly of men.