Oct. 14, 2002 - High doses of the popular supplement coenzyme Q10 helps slow the progression of Parkinson's disease in some patients by as much as half, researchers report.
Their study, published in the Oct. 15 issue of Archives of Neurology, is the latest to examine the possible benefits of coenzyme Q10, a vitamin-like compound naturally produced in the body and used by cells to make energy and protect against cellular damage. It is also sold in supplement form and has been the subject of various studies as a possible treatment for heart disease, cancer, and other ailments.
In this study, 80 patients with early Parkinson's -- none had previously required drug treatment -- took one of several doses of coenzyme Q10 or placebo four times daily for up to 16 months or until they required treatment with traditional medications such as L-dopa.
"We found that all study participants taking coenzyme Q10 did better than those given a placebo, but the real effect was with those receiving the highest dose administered -- 1200 mg daily," lead researcher Clifford Shults, MD, tells WebMD. "In that group, the rate of progressive deterioration was slowed by 44% compared with those patients taking a placebo." Shults is professor of neurosciences at the University of California, San Diego, School of Medicine,
Patients in groups receiving daily coenzyme Q10 doses of 300 mg and 600 mg also experienced reduced rates of deterioration -- about 20% slower than those receiving a placebo, he says.
Coenzyme Q10 is thought to be helpful because Parkinson's patients have impaired function in mitochondria -- cell components that produce most of the body's energy and consume more than 80% of the oxygen we breath. When mitochondria are impaired, renegade "free radical" molecules can more easily damage important parts of the cell, increasing the risk of diseases that are often associated with aging, such as cancer. Parkinson's affects about 1% of all people older than 50, but about 15% are diagnosed earlier -- including actor Michael J. Fox.
When young and healthy, the human body produces about 300 mg of coenzyme Q10 a day. But levels typically begin to decrease after age 30.
Experts are quick to advise that the finding needs to be tested in more people before coenzyme Q10 supplementation can be recommended to prevent or treat Parkinson's disease.
"Am I encouraged by the study? Yes," says Abraham Lieberman, MD, professor of neurology at the University of Miami School of Medicine. "Is it interesting? Yes. Is it innovative research? Yes. Am I convinced that everyone with Parkinson's should load up on coenzyme Q10 based on this finding? No." Lieberman is also medical director of the National Parkinson's Foundation.
"Although very promising, it was a very small study but done by very good people," Lieberman tells WebMD. "It needs to be tested in larger groups before we can recommend that people with Parkinson's go out and spend $300 a month on [coenzyme Q10]in hopes it will help them."
"While tremendously encouraging, ours is only a preliminary finding and still needs to be proved in a larger study," says Shults, who presented his study at the annual meeting of the American Neurological Association. "The next step is to do that, and we're working on a proposal to study the effects of coenzyme Q10 at even higher doses."
One concern: coenzyme Q10 is chemically similar to vitamin K, which is essential for blood clotting. "So it can negate the effectiveness of 'blood-thinning' drugs like Coumadin," says Lieberman. "While there's a study using 3000 mg of coenzyme Q10 to see its effect on ALS (amyotrophic lateral sclerosis, or "Lou Gehrig's disease"), most of the studies testing coenzyme Q10 on heart disease and other conditions involve smaller doses of around 300 mg." -->