Value of carotid intimal–medial thickness as independent predictor of endothelial dysfunction in uremic patients

摘要

Background and aim of the workCardiovascular mortality and morbidity are significantly higher among uremic patients. Although the carotid intimal–medial thickness (C-IMT) as a predictor of endothelial dysfunction (ED) has a prognostic value that has been well demonstrated as an independent predictor of future cardiovascular events, its value in uremic patients need to be re-assisted in our locality. The aim of the work is to investigate a correlation between the brachial artery reactivity test (BART) and the carotid intimal–medial thickening (C-IMT) and their value as independent predictors of endothelial dysfunction in uremic patients.Subjects and methodsThe study involved 70 uremic patients, 40 men and 30 women, 36–56years old, 40 of them on regular hemodialysis (HD) and 30 on conservative therapy, in addition to 30 healthy persons as a control group. They were selected from the General Medicine and Nephrology Departments, Al-Azhar Assiut University and Assiut University Hospitals over a period of 2years. All of them were subjected to detailed history, thorough clinical examination, laboratory investigations including complete blood picture, renal function tests (urine analysis, blood urea, and serum creatinine), lipid profile, serum calcium and serum phosphorus, parathyroid hormone (PTH), fasting blood glucose, electrocardiography (ECG), high resolution B-mode ultra-sonography for C-IMT evaluation and brachial artery reactivity test (BART), and abdominal ultra-sonography.ResultsThe results of the present study showed: (1) uremic patients are at an increased risk for carotid atherosclerotic lesions, with significant increase in C-IMT than controls with more significant increase in HD patients. (2) Uremic patients are characterized by impaired endothelium dependent dilatation of the brachial artery (highly significant reduction in flow-mediated dilatation (FMD%)), an abnormality related to the renal failure severity and to the hemodialysis doses. The endothelial dysfunction in the brachial artery was more pronounced in HD patients than in patients on conservative therapy. (3) Significant positive correlation between increased C-IMT and reduction of the brachial FMD%. (4) Significant relation between C-IMT and plaque prevalence and HD duration, while no relations recorded between brachial FMD with HD duration.Conclusion(1) The study confirmed that carotid IMT and brachial artery FMD can be used in interventional studies in which cardiovascular risk is modified and increased in the uremic patients. (2) There was negative correlation between brachial FMD and C-IMT in the uremic patients.