Parkinson's disease is a progressive neurodegenerative disorder that affects approximately 6 million people worldwide and more than 1.5 million individuals in the United States, and its incidence is expected to increase over the next decade. There is neither a cure nor a treatment that has been proven to slow progression of the disease. Previous study evidence indicates that creatine, an amino acid, plays an important role in cellular energy production, which may be impaired in Parkinson disease; and oral creatine supplementation in mice has suggested a neuroprotective effect.
Researchers randomly assigned 1,741 men and women with early (within 5 years of diagnosis) and treated (receiving dopaminergic therapy) Parkinson disease to receive placebo or creatine monohydrate (10 g/d) for a minimum of 5 years (maximum follow-up, 8 years). Using several measures of Parkinson disease progression, the researchers found that treatment with creatine monohydrate, compared with placebo, did not improve clinical outcomes.