OHSU Study Finds Ginkgo Beneficial For MS Symptoms
04/27/05 Portland, Ore.
Many patients already take herbal supplement available over counter
That's why the stay-at-home mom, who was diagnosed with multiple sclerosis in July 2000, was willing to turn to popular, over-the-counter herbal supplements like ginkgo biloba to deal with memory problems, fatigue and occasional muscle pain.
"I'm definitely interested in alternative medicine," said Winfield, 49, whose form of the neurological disease - relapsing-remitting MS - is characterized by frequent symptom flare-ups. Ginkgo "is not only given to someone like me with MS. There's benefit to anyone taking it."
Findings by scientists in the Oregon Health & Science University School of Medicine's Department of Neurology and the OHSU MS Center of Oregon appear to back up that claim. A study presented this month at the American Academy of Neurology's 57th Annual Meeting in Miami Beach, Fla., suggests that ginkgo may be effective in improving attention in MS patients with cognitive impairment. Side effects also were minimal.
The study's lead author, Jesus Lovera, M.D., a research fellow and instructor in neurology, OHSU School of Medicine, said those receiving ginkgo "performed better on a test that measures a person's ability to pay attention and to sort conflicting information."
Of 39 patients completing the study, 20 received ginkgo biloba and 19 received placebo. Researchers found there were no differences in results between the two groups in the areas of gender, education, type of MS, years since onset, or baseline performance on a battery of neuropsychological tests.
But the ginkgo group was four seconds - about 13 percent - faster than the placebo group on a timed color and word test that measures attention and such "executive functions" as planning, decision making, and controlling goal-directed behavior and execution of deliberate actions.
During the test, called a "Stroop," patients are shown colored boxes and asked to name the colors. They are then shown the names of colors printed with different-colored inks, such as the word "green" printed in red, and asked to read the word. Finally, patients are asked to describe the ink used for each word.
Lovera said the differences in the Stroop result would be comparable to differences in scores between healthy people ages 30 to 39 and those ages 50 to 59.
Ginkgo appeared to be more beneficial for MS patients having specific problems in the Stroop, so "we would like to do another study in which we choose patients that are impaired in this particular test," Lovera said. "We would also like to test it at higher doses."
Ginko biloba is among several complementary and alternative medicine therapies being investigated by OHSU's Department of Neurology for their effects on symptoms of neurological disease. Studies have ranged from clinical trials of lactoferrin for treating Alzheimer's disease to the use of yoga as a therapy for MS fatigue.
Ginkgo is derived from the leaves of the ginkgo tree, one of the oldest species of trees, and has been used for thousands of years by the Chinese as an herbal remedy for a variety of ailments. It contains potent antioxidants called flavoglycosides that have been shown to have neuroprotective effects in animal models of spinal cord injury. It also has terpene-lactones that block a substance known as platelet activitating factor, which is important in regulating blood vessel function as well as the mediating inflammation and the sticking of inflammatory cells to blood vessels.
Many MS patients have long suspected that ginkgo improves disease symptoms. In a recent survey of 1,913 patients in Oregon, 20 percent reported using the supplement and 39 percent found it to be beneficial. However, until now, there was no evidence the supplement had any effect on memory.
"It has been shown to be of benefit in Alzheimer's, but we did not know if it would work for MS," Lovera said. "We wanted to see if there was any suggestion that it could help patients with MS that are having cognitive problems."
Lovera said the study results demonstrate that ginkgo shouldn't be discounted for treating MS, but its safety and efficacy must be tested in much larger clinical trials before doctors should recommend it to their patients.
"The study suggests that for cognitive problems, it may only help a certain group of patients," he said. "We need to study this further."
And for MS sufferers like Winfield, who participated in the ginkgo study, the herbal supplement will remain one of the many weapons in her arsenal for fighting the disease.
"I would do it again," she said of taking ginkgo. "It could have a benefit for me that I didn't have before." But she emphasizes that "every MS is different, so what might work for me may not work for anybody else. But when it comes to alternative medicine, I'm all for that."
The study was supported by the National MS Society, the National Institutes of Health, the U.S. Department of Veterans Affairs and the Nancy Davis Center Without Walls.