Efficacy of Alpha-lipoic Acid in The Management of Diabetes Mellitus: A Systematic Review and Meta-analysis

Alpha-lipoic acid (ALA) is a naturally-occurring compound that has shown promising antioxidant and anti-inflammatory effects in experimental and human studies. The aim of this study was to assess the efficacy of ALA in the management of patients with diabetes mellitus (DM). We searched Medline (via PubMed), EBSCO, Scopus, and Web of Science for relevant randomized controlled trials. Data on glycated hemoglobin (HbA1c), blood glucose levels, lipid profile components, HOMA, and glutathione peroxidase (GPx) were extracted and pooled as the standardized mean difference (SMD) in a random effect model meta-analysis using RevMan version 5.3. Ten studies (n = 553 patients) were included. In the term of HBA1C, the overall SMD did not favor either of the two groups (SMD = 0.01, 95% CI [-0.32,0.35]; p = 0.94) in uncomplicated T2DM patients. Moreover, there was no statistically significant difference between the two groups in terms of FBG (SMD = -0.06, 95% CI [-0.44,0.33]; p = 0.78), PPBG (SMD = 0.04, 95% CI [-0.27,0.34]; p = 0.82), HDL (SMD = -0.05, 95% CI [-0.35,0.25]; p = 0.75), LDL (SMD = -0.05, 95% CI [-0.33,0.23]; p = 0.75). In terms of GPx, ALA was superior to placebo (SMD = 0.43, 95% CI [0.07,0.8]; p = 0.02). Our analysis showed that ALA was not superior to placebo in terms of HBA1C, LDL, HDL, TC, TG reduction in uncomplicated T2DM. However, in terms of GPx, ALA was significantly superior to the placebo. Further studies with larger sample sizes should investigate different doses of ALA in DM patients.