Plasma homocysteine levels in systemic lupus erythematosus]

BACKGROUND AND OBJECTIVE: Cardiovascular disease is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). An association between hyperhomocysteinemia and increased cardiovascular risk has been reported. On the other hand, renal failure and deficiency of vitamin B12 and/or folic acid are common causes of hyperhomocysteinemia. The aims of this study were to determine plasma total homocystein (tHcy) concentrations in SLE patients and to analyze the association of plasma tHcy with age, sex, plasma creatinine, vitamin B12, folates and total cholesterol, as well as with other clinical conditions linked to atherothrombosis in SLE patients. PATIENTS AND METHOD: Fasting plasma levels of tHcy, vitamin B12, folates, total cholesterol and creatinine were measured in 94 SLE patients (11 males, 83 females) and in a control group of 308 healthy volunteers (122 males, 186 females). A review of the medical records of SLE patients was performed. RESULTS: Plasma tHcy concentrations were higher in patients with SLE (median 10.54 (mol/L) than in controls (median 8.49 (mol/L, p < 0.001). Hyperhomocysteinemia (tHcy greater than or equal to15 (mol/L) was found in 17.02% SLE patients. In a multivariate analysis, plasma creatinine (p < 0.001), total cholesterol (p = 0.038), male sex (p = 0.003) and smoking (p = 0.001) were associated with higher plasma tHcy concentrations. No associations were found between plasma tHcy and hypertension, SLE duration, prednisone therapy and antiphospholipid antibodies. CONCLUSIONS: Plasma tHcy concentrations are higher in SLE patients than in healthy controls. High concentrations of plasma creatinine and total plasma cholesterol, male sex and smoking are associated with a higher concentration of plasma tHcy in SLE. Since the clinical consequences of hyperhomocysteinemia are not we established, routine determination of plasmatic tHcy and supplemental therapy in patients with high levels of tHcy are not recommended.