Factors associated with calcification of the abdominal aorta in hemodialysis patients

Abstract

Cardiovascular and cerebrovascular injury caused by arteriosclerosis has been the major cause of the death in hemodialysis (HD) patients. We quantitatively analyzed and evaluated the severity of abdominal aortic calcification in HD patients in comparison to risk factors for arteriosclerosis. One hundred thirty-seven HD patients were examined. Using image analysis software, areas of the calcified abdominal aorta were quantitatively analyzed on plain computerized tomography images. Other factors such as blood pressure (BP), lipid levels, and calcium (Ca) x phosphorus (Pi) value were also analyzed. Patients with a higher one-year average of systolic BP showed a higher severity of abdominal aortic calcification. That is, the severity of abdominal aortic calcification in patients with a one-year systolic BP average above 160 mm Hg was 31.5 +/- 13.6%, and this severity was significantly higher than that in patients with a one-year systolic BP average of less than 120 mm Hg (8.0 +/- 7.7%, P < 0.01). The severity of abdominal aortic calcification in patients demonstrating risk values of ectopic calcification, that is serum Ca x Pi > or = 60 (mg/dl), on more than 4 of 24 measurements within one year (25.8 +/- 13.6%) was significantly higher than the severity of aortic calcification in patients demonstrating this value less than four times in one year (P < 0.05). There was no correlation between levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, lipoprotein(a), and severity of abdominal aortic calcification. Systolic BP levels and the product of serum Ca and Pi were related to the severity of abdominal aortic calcification in HD patients. These observations suggested that BP control, as well as control of serum Ca and Pi levels, was important in preventing the progression of abdominal aortic arteriosclerosis.