Background: Cardiovascular calcification represents a marker of cardiovascular risk in chronic dialysis patients. In the general population, aortic arch calcification (AAC) can predict cardiovascular mortality. We conducted a prospective study to investigate factors associated with AAC in hemodialysis patients and examined its prognostic value in long-term outcome.
Methods: A total of 712 hemodialysis patients were enrolled. AAC was identified on postero-anterior chest X-ray films and classified as grade (Gr.) 0, 1, 2 or 3. Demographic data including age, gender, dialysis vintage, co-morbidity and biochemical data were reviewed and recorded. The patients were followed for 10 years.
Results: AAC was present in 164 patients (23%) as Gr. 1, in 116 patients (16.3%) as Gr. 2 and in 126 patients (17.7%) as Gr. 3. An increase in the severity of calcification was associated with older patients who had lower albumin, higher calcium and glucose levels. During the follow-up period of 10 years, we found that the grade of AAC was directly related to cardiovascular mortality (Gr. 0: 5.3%; Gr. 1: 12.7%; Gr. 2: 18.9%, and Gr. 3: 24.4%; p < 0.05) and all-cause mortality (Gr. 0: 19.9%; Gr. 1: 31.1%; Gr. 2: 44.8%, and Gr. 3: 53.2%; p < 0.001). Multivariate Cox proportional hazards analysis revealed that high-grade calcification was associated with cardiovascular and all-cause mortality. Patients with AAC were associated with a worse outcome in survival analysis. The severity of AAC also influenced their survival.
Conclusion: Calcification of the aortic arch detected in plain chest radiography was an important determinant of cardiovascular as well as all-cause mortality in chronic hemodialysis patients. The presence and severity of AAC predicted long-term survival.
Keywords: Hemodialysis; Survival; Vascular calcification.