Background/aims: An increasing body of evidence demonstrates that L-carnitine plays a pivotal role in lipid metabolism of hemodialysis (HD) patients. However, there are still some reservations about its benefits. Therefore, we performed a meta-analysis to assess the effects of L-carnitine supplementation on lipid profile in HD patients.
Methods: Literature search was performed to identify the relevant randomized controlled trials that investigated the effects of L-carnitine on the lipid profile of subjects. Two independent authors used an Excel file to extract data and assess trials quality. The primary effect measure was the difference in means of the final lipid measurements between the intervention and control groups. The meta-analysis was performed with the fixed-effects model or random-effects model according to heterogeneity.
Results: Twelve studies with a total of 391 patients met the inclusion criteria. The use of L-carnitine was not associated with a reduction in the total cholesterol (SMD, -0.11; 95% CI, -0.31 to 0.09), HDL-cholesterol (SMD, 0.01; 95% CI, -0.36 to 0.39), VLDL-cholesterol (SMD, 0.54; 95% CI, -0.06 to 1.14), and the serum triglycerides (SMD, -0.12; 95% CI, -0.36 to 0.12). However, L-carnitine can significantly decrease the LDL-cholesterol (SMD, -0.29; 95% CI, -0.53 to -0.06) in HD patients. In a subgroup meta-analysis, a significant LDL-cholesterol-lowering effect of L-carnitine supplementation was observed in intravenous application group, and patients with longer interventional duration and renal diseases.
Conclusion: The limited evidence suggests that there was no effect of L-carnitine on serum total cholesterol, HDL-cholesterol, VLDL-cholesterol and serum triglycerides. By contrast, this meta-analysis suggests a promising effect of L-carnitine on LDL-cholesterol. Further large-scale, well-designed randomized controlled trials are urgently needed