Effect of Oral Creatine on Muscle Metabolism of Duchenne Muscular Dystrophy (DMD) by Phosphorus MRS

INTRODUCTION DMD is an X-linked recessive disease which occurs due to deficiency of dystrophin; an important component of muscle cytoskeleton. It is the most common form of muscular dystrophy affecting 1 in 3300 live male births. In spite of extensive research in humans and mdx mouse models no satisfactory therapeutic approach has been developed. In DMD patients, low phosphocreatine (PCr) / phosphorus (Pi) and PCr /Adenosine tri phosphate (ATP) ratios have been reported using P MRS of skeletal muscle in vivo. In vitro results also reported significant reduction in the concentration of total creatine and several other metabolites in DMD patients compared to normal subjects. In literature few studies reported a positive effect of creatine supplementation in DMD patients which is encouraging albeit with different dose, duration and outcome measures . A recent randomized, double blind placebo controlled trial failed to demonstrate a statistically significant effect of creatine on muscle strength though a disease modifying effect of creatine was noticed in younger patients (< 7 years age). We therefore designed the present study to investigate the effect of oral creatine monohydrate supplementation versus placebo on muscle metabolism using PMRS and correlation of changes in muscle strength and functional level in a large cohort of patients.