C-reactive protein, lipoprotein(a), homocysteine, and male sex contribute to carotid atherosclerosis in peritoneal dialysis patients

Abstract

Background:In patients with end-stage renal disease, the morbidity and mortality of cardiovascular disease are substantially greater than in the general population. Advancement in understanding the pathogenesis of atherosclerotic vascular disease suggests a central role of inflammation in atherogenesis. However, clinical data evaluating the role of inflammation in atherogenesis are sparse in peritoneal dialysis (PD) patients. Methods:We measured serum C-reactive protein (CRP), intact parathyroid hormone, lipoprotein(a) [Lp(a)], interleukin-1 receptor antagonist (IL-1Ra), tumor necrosis factor soluble receptor (TNF-sR), fibrinogen, and plasma homocysteine (Hcy), as well as intima-media thickness (IMT) and number of atherosclerotic plaques (plaque score [PS]) in the carotid arteries by means of carotid B-mode ultrasonography in 59 PD patients (35 men, 24 women; mean age, 52.4 years; average dialysis period, 36 months). All patients had chronic glomerulonephritis. Results:Sixty-eight percent of PD patients had at least 1 plaque. Serum CRP level was greater than the upper limit of the normal range in 52.5% of patients. Compared with PD patients with normal CRP levels, concentrations of such proinflammatory cytokines as IL-1Ra and TNF-sR, Lp(a), and Hcy were increased in PD patients with elevated CRP levels. However, no differences in plasma fibrinogen and intact parathyroid hormone levels were found between PD patients with increased and normal CRP levels. In a multiple regression model, age, male sex, CRP level, and Lp(a) level were independent predictors of IMT. Similarly, male sex, CRP level, Lp(a) level, and Hcy level were independent correlates of PS. Conclusion:This study suggests that Lp(a) and Hcy levels and male sex, and especially CRP level, have an important role in carotid atherosclerosis in PD patients.