Assessment of abdominal aortic calcification at different stages of chronic kidney disease

Purpose: Vascular calcifications that may cause cardiovascular disease are highly prevalent in chronic kidney disease (CKD). In this study, we aimed to determine abdominal aorta calcifications (AAC) in predialysis and hemodialysis patients by lateral lumbar radiography and to investigate factors that were associated with the calcifications. Methods: Two hundred and fifty-nine adult chronic hemodialysis patients, 300 predialysis CKD patients and 60 healthy subjects with normal kidney function as a control group were enrolled in the study. Lateral lumbar radiography was used to measure AAC. Calcified deposits of the abdominal aorta wall at the level of the first through fourth lumbar vertebrae were graded by a 24-point scoring system. Results: AAC prevalence (AAC score ≥1) was significantly different in hemodialysis, predialysis and control groups (71.8, 45.7 and 33.3 %, respectively; p < 0.001). AAC prevalence in CKD stages 1, 2, 3, 4 and 5 predialysis patients was 26.6, 43.3, 40, 58.3 and 55 %, respectively. AAC scores of the hemodialysis group were higher than of the predialysis group (p < 0.001) and the control group (p < 0.001). AAC scores of the predialysis group were not higher than of the control group (p = 0.314). AAC scores of the hemodialysis group were significantly higher than of the control group (p < 0.001) and stage 1 (p < 0.001), stage 2 (p = 0.001) and stage 3 predialysis groups (p = 0.002). Age (p < 0.001), presence of diabetes mellitus (p < 0.001) and serum phosphorus levels (p = 0.011) were found to be independent predictors of calcification in the hemodialysis group. Age (p < 0.001), serum phosphorus levels (p = 0.007) and history of cardiovascular disease (p = 0.014) were found to be independent predictors of calcification in the predialysis group. Conclusions: Abdominal aortic calcification is highly prevalent in the hemodialysis population. Strict phosphorus control should be implemented to the predialysis and hemodialysis patients.