A meta-analysis of randomized and placebo-controlled clinical trials suggests that coenzyme Q10 at low dose improves glucose and HbA1c levels

Abstract

The influence of coenzyme Q10 (CoQ10) on blood glucose (BGL) and HbA1c (HL) levels has been previously investigated; however, the results are inconsistent. Therefore, the purpose of this meta-analysis was to determine if CoQ10 could affect BGL and HL levels based on the existing evidence. PubMed, Cochrane Library, Web of Science, Embase, and Scopus databases were searched for randomized clinical trials from September 1, 1956, to March 01, 2016. To calculate pooled overall effects, a random effect model was used. Because of the presence of heterogeneity, the subgroup analysis and the meta-regression were performed. In total, 18 studies (19 study arms) were included in our investigation focusing on the effects of CoQ10 on BGL (17 arms) and HL (12 arms) changes. CoQ10 significantly reduced BGL, whereas it was ineffective in the reduction of the HL. Because of the significant heterogeneity, in the arms involving BGL, we found that lower doses of CoQ10 (<200 mg/d) and a shorter duration of study created a positive effect on BGL. Also, it appeared that CoQ10 could reduce BGL in patients with a glucose level > 6 mmol/L as well as in certain ethnic groups. However, because the meta-regression failed to support the subgroup analysis, the result related to the ethnic group should be used only to generate a hypothesis, which is planned in the future. In conclusion, CoQ10 can reduce BGL, particularly when used in lower doses (< 200 mg/d) and when administration was not longer than 12 weeks, in patients both with and without high BGL. © 2016 Elsevier Inc.