Associations Between Coronary Calcification on Chest Radiographs and Mortality in Hemodialysis Patients

Abstract

Background KDIGO (Kidney Disease: Improving Global Outcomes) guidelines recommend lateral abdominal radiographs to assess vascular calcification in incident dialysis patients. However, nearly all dialysis patients in the US receive chest radiographs at dialysis inception which may provide readily available information on coronary artery calcification (CAC) and aortic arch calcification (AAC). We determined the prevalence of CAC and AAC visible on plain chest radiographs and their associations with mortality in our dialysis population. Study Design Retrospective Analysis Setting & Participants 93 participants who received maintenance hemodialysis at the San Diego VAMC in 2009–2010 Predictor Presence of CAC and AAC as evaluated by a radiologist Outcome All cause mortality Results The average age was 64; 22% were African-American, and 97% were male. CAC and AAC prevalence were 25% and 58%, respectively. During 20 months’ follow-up, 28% died. CAC was strongly associated with mortality in models including cardiovascular (HR, 2.41; 95% CI 1.04–5.59) and dialysis-related (HR, 2.86; 95% CI 1.24–6.6) risk factors. AAC was associated with a HR of 5.25 (95% CI, 1.46–17.72) in cardiovascular risk-factor adjusted models and 7.31 (95% CI, 2.03–26.34) in dialysis models. When CAC and AAC were both included in models, both CAC (HR, 3.40; 95% CI, 1.24–9.36) and AAC (HR, 6.23; 95% CI, 1.64–23.66) remained significantly associated with mortality. Limitations The study sample is relatively small and mostly male. Conclusions CAC and AAC are highly prevalent on chest radiographs in dialysis patients, and strongly associated with mortality independent of one another. Since these images are nearly ubiquitous, inexpensive, and often already obtained for other indications, they should be considered for risk assessment in hemodialysis patients. Future studies are required to determine whether CAC or AAC on chest radiography is additive or duplicative of the risk of aorto-iliac calcification on lateral abdominal radiographs currently suggested by KDIGO.

Abdominal aortic calcification is not superior over other vascular calcification in predicting mortality in hemodialysis patients: a retrospective observational study

“…The prevalence of aortic calcification has been reported to be more than 50% in CKD patients [5,6,11], which is in accordance with our results. This may be associated with several risk factors, including increasing age [12], genetic factors [20] and body composition [21] in addition to traditional cardiovascular risk factors and CKD/dialysis-related risk factors.…”

“…Besides traditional risk factors for cardiovascular disease, mineral bone disorders associated with chronic renal disease, and vascular calcifications (VC) in particular, have been identified as disease-specific risk factors for cardiovascular disease (CVD) in hemodialysis patients [3-5]. In clinical observations, a strong relationship between coronary artery calcification and cardiovascular mortality has been reported in hemodialysis patients [6-9]. However, due to its high cost and radiation exposure, computed tomography (CT) is not recommended as a routine or screening technique for VC.…”

“…Few studies have analyzed the confounding effects of different regions of VC on the prognosis of hemodialysis patients. One study showed that both coronary artery calcification (HR, 3.40; 95%CI, 1.24-9.36) and aortic arch calcification (HR, 6.23; 95%CI, 1.64-23.66) remained significantly associated with mortality after they were adjusted for each other [6]. A simple scoring system to evaluate VC in hemodialysis patients has identified a positive correlation between outcomes and this VC score [15].…”

Individualization of Dialysate Calcium Concentration According to Baseline Pre-Dialysis Serum Calcium

“…Dialysis patients have a high incidence of vascular calcification, which is associated with increased cardiovascular mortality [1,2]. Calcium and phosphate are among the several factors that modulate vascular calcification [3].…”

Vascular Calcification Progression Is an Independent Predictor of Mortality in Patients on Haemodialysis

“…More recently, it has become evident that VC is 2-10 times more frequent in CKD and ESRD patients compared with the general population [23,24]. Several studies suggest that VC is associated with coronary atherosclerosis, vascular wall stiffness [25,26], peripheral vascular disease [27], left ventricular hypertrophy [28], and subsequent increases in mortality [25,29]. …”