By Trevor Stokes
NEW YORK (Reuters Health) - Creatine, a supplement favored by bodybuilders, modestly boosted muscle strength in patients with fibromyalgia, Brazilian researchers report.
Apart from helping with muscle weakness, though, the treatment had little effect on other symptoms of the mysterious disorder, such as chronic pain, fatigue, memory loss, depression, anxiety and sleeplessness.
"The improvements in muscle function did not reflect improvements in general symptoms as we hypothesized," said senior study author Bruno Gualano, a professor at the University of São Paulo School of Physical Education and Sports in Brazil.
As many as one in 50 Americans suffers from fibromyalgia, according to the U.S. Centers for Disease Control and Prevention. The condition typically strikes in middle age, affects women more often than men and is thought to be triggered by stress.
Current treatments for fibromyalgia symptoms include three FDA-approved drugs - antidepressants Savella and Cymbalta, plus the nerve-pain medication Lyrica - along with antiepileptic drugs and sedatives. Experts noted, however, that the drugs are not very effective and come with many side effects.
Non-drug treatments for fibromyalgia include exercise, massage and meditation.
Previous research has found that brain and muscle tissues in fibromyalgia patients have reduced levels of creatine - a chemical critical to cells' ability to generate energy - which might explain the weakness and neurological symptoms, Gualano and his colleagues note in the journal Arthritis Care & Research.
One study found that creatine supplements improved general fibromyalgia symptoms, but the research was not rigorously done, which made the results difficult to interpret.
So Gualano's team conducted a 16-week double-blind, randomized, controlled trial, the gold standard for medical research, in which fibromyalgia patients daily consumed either creatine (15 patients) or placebo pills (13 patients).
Neither the trial staff nor the patients knew who was getting the real supplement, or even what substance the supplement was supposed to be, until after the study period was complete.
At that point, the creatine-supplemented group showed modest strength improvements when tested on leg presses (10 percent improvement) and chest presses (8 percent improvement).
But, participants were also surveyed on an array of other symptoms, including their pain levels, moods and sleep, and those in the supplement group didn't report any changes in overall quality of life.
"It was a well-done study, but not very exciting," said Dr. Don Goldenberg, rheumatology chief at Newton-Wellesley Hospital in Boston, who was not involved in the study.
Most researchers consider fibromyalgia a disease of the nervous rather than muscle system, Goldenberg said.
"Muscle strength is not a primary problem for people with fibromyalgia; it's chronic pain and fatigue," he told Reuters Health.
He wasn't surprised that creatine supplements didn't affect a host of other symptoms.
"I would encourage people to do strengthening exercise rather than to use a supplement to strengthen," Goldenberg said. "To say that (creatine supplementation) is something that I'm going to recommend to my patients? No."
"I don't think patients are going to gain much at all (from the study); false hope perhaps," said Pam Stewart, chairwoman of the non-profit Fibromyalgia UK. "The extra strength it gives to muscles is not long lasting and in everyday life, that isn't usually what patients need."
Instead, patients need to get better sleep, lead less stressful lives and pursue low-impact exercises, Stewart told Reuters Health.
Still, because anti-fibromyalgia medicines typically target the brain, but have limited effectiveness and several side effects, their use is limited and researchers applauded any attempts to find alternatives.
"Looking at new approaches is a really important thing to do," Goldenberg said. "I'm just not that enthusiastic about this particular approach."
For chronic pain, Goldenberg thinks the longer the disease is not treated or diagnosed, the worse the symptoms become.
"One of the messages for people is get an early diagnosis and get early therapy," Goldenberg said. However, "many chronic pain syndromes have overlapping symptoms, making diagnosis difficult."
Though creatine failed to pan out as a therapy on its own, Gualano said that he'd like future studies to combine the supplement with exercise and anti-fibromyalgia drugs to see if it enhances their effects.
Gualano also said he would recommend creatine supplementation to help build muscle and strength in patients, but stressed that exercise is also very important for all fibromyalgia patients.
"Exercise is the most important therapeutic tool that physicians have to treat rheumatic patients including fibromyalgia," Gualano said.
SOURCE: bit.ly/12GtIuD Arthritis Care & Research, online April 1, 2013.