Study Finds Supplement Slows Down Parkinson’s

A common food supplement called coenzyme Q-10 can significantly delay the progression of Parkinson’s disease, slowing the degeneration of brain cells, a UC San Diego-led team reports today. A nationwide trial in 80 patients found that the supplement can reduce progression of the debilitating disorder by as much as 44%, prolonging the period in which patients can carry out such everyday functions as feeding, dressing, bathing and walking.

But the study’s authors and other experts cautioned patients against taking the supplement on their own until its value can be proven in a larger study.

“It’s very interesting, and they may be on to something, but they need a larger study,” said Dr. Abraham Lieberman of the National Parkinson Foundation. “It’s going to be another three to four years before we can say for sure whether this works or not.”

That larger study should begin as soon as possible, said Dr. Bernard Ravina of the National Institute of Neurological Disorders and Stroke, which funded the current study. Scientists should follow up on it “pretty aggressively,” he said.

Parkinson’s, which strikes as many as 100,000 Americans each year, is characterized by severe tremors and rigidity in the limbs and loss of muscle control. Although its primary cause is unknown, the disorder results from the death of brain cells that produce dopamine, which plays a key role in transmitting commands from the brain’s muscle-control centers.

The first line of treatment is the use of drugs, such as l-dopa, which stimulate production of dopamine. Those drugs alleviate symptoms of the disease, but do not delay progression. Results with two new drugs called mirapex and ropinirole, released earlier this year, suggest that they do delay progression, but only by about half as much as coenzyme Q-10 did in the new study.

The San Diego team had a good reason to test the supplement, Lieberman said.

Coenzyme Q-10, also known as ubiquinone, plays a key role in mitochondria, energy-producing sites within each cell of the body. More than a decade of research by Dr. Clifford Shults and Dr. Richard Haas of UC San Diego and Dr. Flint Beal, now at Cornell University’s Weill Medical College, showed that mitochondria function is impaired in the brains of patients with Parkinson’s disease, and that levels of ubiquinone are unusually low in these mitochondria.

The supplement is also an antioxidant, and other studies have suggested that antioxidants are useful in treating Parkinson’s.

Studies of mice with a Parkinson-like disease showed that administering coenzyme Q-10 could preserve brain tissue. A preliminary study in 15 humans suggested the same thing.

The current study involved patients who were recently diagnosed with Parkinson’s and who were not taking any other medications for the disorder. The coenzyme Q-10 and placebo used in the study were formulated into wafers by Vitaline Formula of Ashland, Ore.

Half the 80 patients received a placebo. The other half received either 300, 600 or 1,200 milligrams of coenzyme Q-10 every day for 16 months or until they required therapy with other drugs. Their ability to carry out everyday functions was evaluated at regular intervals.

The team reports today in the Archives of Neurology that patients receiving the lower doses of coenzyme Q-10 fared better than those receiving the placebo, and that the 23 patients receiving the highest dose fared significantly better. The results did not begin to become apparent until several months into the study, indicating that the supplement does not ameliorate symptoms, but rather that it delays progression.

That is, patients don’t get better when they take the supplement. They just don’t get worse as fast.

The results “are tremendously encouraging,” Shults said.

“However, before the compound is widely used, the results need to be confirmed in a larger group of patients.” He cautioned that widespread use of the supplement by patients would make it difficult to recruit enough patients for a definitive study.

The supplement is also relatively expensive. “The dose of Q-10 that you need costs $150 to $300 per month” and insurance companies will not pay for it, Lieberman said, “so you would be asking people to spend $2,000 to $3,000 per year on a compound that may not do what the study says it is going to do.”

Many Parkinson’s patients are elderly and already paying as much as $3,000 per year for medications on limited budgets.

“Unless you are fairly well-to-do, that is a lot of money,” Lieberman said.