Creatine and CoQ10 with physical activity on muscle function in children with myositis: a proof-of-concept trial

OBJECTIVES: We aimed to evaluate whether Creatine (Cr) and Coenzyme Q10 (CoQ10) supplementation, combined with a self-paced physical activity program, enhances muscle function in juvenile idiopathic inflammatory myopathies (JIIM). METHODS: Fifteen participants, (8 male/ 7 female) aged 9-17, from SickKids' JIIM clinic were recruited for a double-blinded, placebo-controlled, randomized, multiple-baseline trial. All participants participated in both the placebo and intervention periods. The primary outcome, muscle function, was measured by the Wingate Test. Secondary outcomes included improvements in jumping height, disease activity, and quality of life. RESULTS: There was a significant increase in peak power (mean difference (MD)=95 Watts; p = 0.02), mean power (MD = 74 Watts; p = 0.02), and minimum power (MD = 47 Watts; p = 0.01) in the intervention periods compared to placebo periods. Vertical jump peak power also increased significantly in the intervention period (MD = 493 Watts; p = 0.02). However, these significant findings were not replicated in the prespecified sensitivity analyses, which incorporated linear mixed models to adjust for individual baseline values. CONCLUSIONS: Cr+CoQ10 supplementation combined with physical activity showed positive effects; however, these findings may be attributable to chance imbalances in baseline values. Alternatively, the lack of statistical significance in the sensitivity analyses may reflect a Type II error, as the study size was set for the more powerful primary analysis. Further research is necessary to fully understand the impact of Cr and CoQ10 supplementation in children with JIIM. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04286178.