Background An elevated homocysteine level is associated with an increased risk for developing atherosclerosis, which can in turn lead to coronary artery disease (CAD). The risk of cardiovascular events in patients with hyperhomocysteinemia increases more than 3-fold. Systemic lupus erythematosus (SLE) is characterized by early and accelerated atherosclerosis developed due to autoimmune inflammation. Intima-media thickness (IMT) of the common carotid artery (CCA) is associated with subclinical atherosclerosis and can reflect coronary damage.
Objectives The aim of our study was to determine the presence of hyperhomocysteine and its association with cytokines, inflammatory markers in patients with SLE.
Methods We examined 24 female patients with SLE (mean age 41,50 (31,50; 50,50) years old) and with subclinical atherosclerosis revealed ultrasonographically. The comparison group included 22 patients with CAD and the history of myocardial infarction (MI) developed at the mean age of 49,0 (45,0;51,0) years old. We assessed the presence of traditional risk factors. The levels of homocysteine, high sensitive C- reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor - α (TNF-α) were determined with ELISA.
Results The IMT CCA and the presence of atherosclerotic plaques were not statistically different both in the patients with SLE and these with CAD. Frequency of occurrence of risk factors (smoking, obesity, physical inactivity, arterial hypertension, family history of early MI, high levels of total cholesterol, LDL cholesterol, and low levels of HDL cholesterol) was not statistically different in both the groups.
Hyperhomocysteinemia was identified in 58,33% patients with SLE and in 22,73% patients with CAD and was more pronounced in the first group (χ2=6,0; p=0,014). The levels of homocysteine were higher in patients with SLE than with CAD (p=0,033). We revealed high positive correlation between elevated levels of homocysteine and TNF-α in SLE patients (p=0,040). The levels of TNF-α and IL-6 were higher in patients with SLE than with CAD (p=0,001 and p=0,015, respectively). The frequency of high levels of IL-6 was higher in SLE patients than in the other group (p=0,041). Frequency of occurrence of elevated levels of hs-CRP and fibrinogen, as well as their levels were not statistically different in both the groups.
Conclusions These data confirm that the early carotid atherosclerosis in patients with SLE may be a predictor of coronary artery lesions as well as in patients with CAD. Inflammatory process, elevated levels of homocysteine, proinflammatory cytokines (IL-6, TNF-α) are associated with early atherosclerosis in patients with SLE as a result of autoimmune inflammation.
Disclosure of Interest None declared