Taking supplements of creatine to slow the muscular disease amyotrophic lateral sclerosis (ALS) may be a waste of time and money, conclude the authors of a new clinical trial published this week.
The results from researchers in the Netherlands will come as a disappointment to the many patients with ALS (popularly called Lou Gehrig's disease in the United States) taking the nutritional supplement in an attempt to slow the devastating disease, which greatly shortens lives.
"No effect of creatine on disease progression could be found. Patients taking creatine progressed as fast as patients taking placebo and life was not extended due to creatine," said lead author Dr Geert Jan Groeneveld, a neurologist at University Medical Center Utrecht in the Netherlands.
Amyotrophic lateral sclerosis is a disease of the nerve cells that control muscle action. For unknown reasons, the cells and their nerve fibres slowly deteriorate, leading to weakness, muscle spasms and tremors, and eventually, paralysis. The great majority of patients die within ten years, half within three years.
Exercises can help maintain muscle strength and drugs may alleviate muscle spasms or cramps, but there is no cure for the disease. Riluzole, the only drug specifically approved for ALS, has only a modest effect on the progression of the disease.
Many patients with ALS began taking creatine several years ago -either on their own or on a doctor's recommendation - following the publication of a study in which creatine extended the lives of mice with an experimentally induced form of ALS. Hope was also drawn from research indicating that creatine helped athletes build muscles faster.
To address the value of creatine in slowing the decline of ALS, Groeneveld and his colleagues from several institutions in the Netherlands assigned 175 ALS patients to receive either 10 grams of creatine daily or a placebo. Neither the patients nor their doctors knew whether the patient was in the experimental or control group. They published their findings yesterday in the online edition of the Annals of Neurology.
After an average of just over ten months, results already indicated that creatine was not having a substantial beneficial effect on patients. During the study, 30 of the 87 patients in the creatine group died, compared to 28 of 88 patients in the control group. Also, there was no indication that creatine slowed the rate of decline in muscle strength, said researchers. There was no indication in the trial that creatine was unsafe.
The team pointed out that they used new theories of clinical trial design that allowed them to monitor the results more closely as the study progresses, and reach conclusions in a shorter time. This did however mean that small effects of a drug are harder to detect.
There remains a possibility that a smaller benefit would be revealed in a larger trial, said Groeneveld. "But if patients are paying a lot of money for creatine, they should consider stopping the treatment."
It is also possible that creatine will show modest benefits for ALS patients in two US trials of creatine, which are still enrolling patients, or that creatine could have usefulness in other doses or in combination with other drugs.
However it seems that researchers are not holding out great hope for that possibility. "I believe the trial effectively rules out the value in ongoing use of creatine, at least at that dose. And my suspicion is that higher doses, if effective at all, would be of marginal benefit," said Dr Jeffrey D. Rothstein, an expert in ALS at Johns Hopkins University in the US.