Thirty-month follow-up of coronary artery calcification in hemodialysis patients: different roles for inflammation and abnormal calcium-phosphorous metabolism?

BACKGROUND: Cardiovascular disease is the leading cause of death in hemodialysis (HD) patients. Coronary artery calcification (CAC) is considered a marker of atherosclerosis and coronary artery disease (CAD). The CAC progression and factors that influence it were evaluated during a 30-month period. METHODS: Forty HD patients without a history of CAD were enrolled into the study. CAC score was assessed with conventional CT repeated every six months. The circulating factors of phosphorous, calcium, calcium-phosphorous product, intact parathyroid hormone, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, lipoprotein-alpha, albumin, high sensitivity C-reactive protein, and fibrinogen were measured monthly. Hypertension and calcium intake during the study period were taken into account as well. RESULTS: At baseline, CAC score was correlated with age and duration of HD therapy. From all evaluated factors, CAC initiation was influenced only by older age and C-reactive protein. CAC, when it was started, was aggravated continuously and was influenced only by elevated serum phosphorous and calcium-phosphorous product. Hypertension, lipid profile, and calcium intake did not affect CAC initiation or progression. CONCLUSIONS: Once CAC progression starts, it is an uninterrupted process. The roles of inflammation and abnormal calcium-phosphorous metabolism in CAC differ. Inflammation is the major factor that contributes in CAC initiation. Elevated serum phosphorous and calcium-phosphorous product accelerates CAC progression.

The value of computed tomography-derived coronary artery calcification score in coronary artery disease detection in asymptomatic hemodialysis patients.

BACKGROUND: We evaluated the value of coronary artery calcification (CAC) score in coronary artery disease (CAD) detection in asymptomatic hemodialysis (HD) patients by evaluating the association among CAC score, exercise electrocardiography (EECG), and Thallium-201 dipyridamole scintigraphy. Correlation between aortic pulse wave velocity (PWV) and CAC score was also evaluated. METHODS: CAC score was assessed with conventional computed tomography in 40 patients. Thirty patients completed EECG and 25; those with a positive CAC score and/or a positive EECG performed Thallium dipyridamole scintigraphy. Carotid-femoral PWV was assessed in all patients. RESULTS: There was no association among CAC score and EECG or Thallium dipyridamole scintigraphy. In contrast, CAC score was correlated with aortic PWV. CONCLUSION: The previous results question the role of CAC score in the detection of CAD in asymptomatic HD patients. The correlation between CAC score and aortic PWV raises the possibility that CAC score represents more an indicator of coronary artery medial wall calcification than a marker of CAD.