Effects of L-carnitine supplement on plasma coagulation and anticoagulation factors in hemodialysis patients

Hypercoagulability is an important risk factor for thrombosis and its complications such as ischemic heart disease, stroke and arteriovenous fistula failure in hemodialysis patients. The present study was designed to investigate the effects of L-carnitine supplement on plasma coagulation and anticoagulation factors in hemodialysis patients. The study was a double-blind randomized clinical trial. Fourty-two hemodialysis patients (25 females and 17 males) were randomly assigned to either a carnitine or a placebo group. The patients in the carnitine group received orally a vial containing 1000 mg L-carnitine daily for 12 weeks, while the placebo group received a corresponding placebo vial. At baseline and at the end of week 12 of the study, 8.5 ml blood was collected from each patient after a 12- to 14-hour fast before dialysis and plasma fibrinogen concentration, activity of plasma protein C, coagulation factors V, VII, IX, and serum concentrations of tPA, PAI-1, free carnitine and CRP were measured. In the carnitine group the mean serum free carnitine concentration increased significantly 150%, while the plasma fibrinogen and the serum CRP decreased 98 mg/dl and 41%, respectively, at the end of week 12, as compared to the baseline value (P<0.001). The reductions were significant as compared to the placebo group (P<0.05). No significant differences were observed between the two groups with regard to mean changes in the activity of plasma protein C, coagulation factors V, VII, IX, and serum PAI-1-to-tPA ratio. The results of the present study indicate that L-carnitine supplement can reduce serum CRP, a systemic inflammatory indicator, and plasma fibrinogen, an inflammation-related coagulation factor, in hemodialysis patients, while it has no effect on coagulation and anticoagulation factors not related to inflammation.