Clinical features of hemodialysis patients with intimal versus medial vascular calcifications

Abstract

Background: Vascular calcifications ( VCs) contribute to the massive mortality in hemodialysis ( HD) patients. We aimed to identify prevalence and risk factors for arterial medial calcifications ( AMCs) versus intimal calcifications ( AICs) in a single-center HD population. Methods: This cross-sectional study included 134 patients, mean age 56.9 +/- 9.7 years, on HD for 8.2 +/- 5.0 years. VCs were scored based on plain radiographs and ultrasonography of the common carotid arteries. Results: Patients were categorized into groups I ( 13% without VC), II ( 10% with an AMC pattern), III ( 24% with an AIC pattern) and IV ( 53% with a mixed pattern). AIC and mixed patterns were associated with older age ( p=0.006 and p=0.004, respectively), and mixed pattern with longer dialysis vintage ( p=0.001). Pulse pressure was significantly higher in patients from group III than group IV, and intima-media thickness ( IMT) was higher in both groups with AIC. By multivariate analysis, risk factors for any VC were high serum Ca, phosphate, Ca x P product, low total protein, high body mass index ( BMI), systolic and diastolic blood pressure, IMT and history of smoking. Elevated calcium and/or phosphate predicted an AMC pattern, and high calcium, BMI and IMT an AIC pattern. Finally, high IMT, systolic blood pressure, BMI and older age were predictors of a mixed pattern. Conclusion: We observed a very high prevalence of VC, mostly with a mixed AIC+AMC pattern. Apart from well-known risk factors, the data stress the importance of smoking, an under-recognized cause of AMC, and systolic blood pressure for AIC+AMC.