Inflammation as a Risk Factor for Carotid IntimalMedial Thickening, a Measure of Subclinical Atherosclerosis in Hemodialysis Patients and the Role of Chlamydia and Cytomegalovirus Infection

OBJECTIVE: Atherosclerotic vascular disease (AVD) is the most frequent complication seen in hemodialysis (HD) patients. Evidence suggests that inflammation may play a role in the pathogenesis and progression of atherosclerosis. Our aim was to evaluate the causative role of inflammation in atherosclerosis among HD patients. METHODS: Intima-media thickness (IMT) in carotid arteries was determined in 54 HD patients and 52 controls. Plasma levels of lipids, glucose, albumin and several acute phase proteins, and IgG titers against Chlamydia and CMV were measured in all subjects. RESULTS: Mean carotid IMT was significantly greater in HD patients than in controls (0.75 mm versus 0.56 mm, p<0.005). Increasing carotid IMT was associated with advancing age in both groups. While plasma levels of CRP, SAA, Lp(a), fibrinogen and ferritin were higher in HD patients, albumin levels were lower. In HD patients, carotid IMT was correlated positively with CRP (R=0.29, p=0.019), SAA (R=0.69, p<0.001), Lp(a) (R=0.42, P=0.001), fibrinogen (R=0.57, p<0.001), and with Chlamydia pneumonia IgG titers (R=0.50, p<0.001), and negatively with albumin levels (R=-0.33, p=0.02); there was no relationship between carotid IMT and hypertension, plasma lipid levels, and CMV. Moreover, CRP and SAA were positively correlated with fibrinogen, Lp(a) and Chlamydia, and inversely with albumin levels in HD patients. CONCLUSIONS: We conclude that atherosclerotic changes are more common in HD patients than controls, and that inflammatory processes may play a role in the pathogenesis of atherosclerosis. Also, past Chlamydial infection might be more atherogenic than CMV.