Healthy Seniors Needed For Study To Determine If Ginkgo Biloba Can Prevent Memory Problems In Dementia
PITTSBURGH, August 28, 2000 — Can the extract of the leaves of the 200 million-year-old Ginkgo biloba tree prevent or delay memory loss, thinking and personality changes that can occur as people grow older? In order to address this question, the University of Pittsburgh is looking for healthy people who are at least 75 years old to participate in a $15 million National Institutes of Health study.
Funded by the National Center for Complementary and Alternative Medicine in collaboration with the National Institute on Aging, National Heart, Lung and Blood Institute, and the National Institute for Neurological Diseases and Stroke (four components of the National Institutes of Health), the Ginkgo Evaluation of Memory Study (GEMS) is the first large-scale, scientifically based evaluation of Ginkgo biloba for the prevention of dementia. The study also will attempt to determine if the substance can prevent cardiovascular problems, including stroke and atherosclerosis.
Researchers hope to enroll a total of 3,000 seniors -- about 750 each at the University of Pittsburgh and the University of Washington in Seattle, Johns Hopkins University, Wake Forest University in North Carolina and the University of California at Davis. Some of the participants will be drawn from the ongoing Cardiovascular Health Study, sponsored by the National Heart, Lung and Blood Institute, which has been observing the health changes of nearly 6,000 men and women for more than 10 years.
As people age, changes in memory, thinking and personality, severe enough to interfere with daily function can lead to significant impairment. Between one third and one half of the population over the age of 75 experiences these changes, collectively referred to as dementia. The most serious form of dementia is Alzheimer's disease, which affects about 4 million people in the United States. Such numbers are expected to grow more than three-fold -- an estimated 14 million baby boomers are at risk for developing Alzheimer's in the next 20 to 30 years. There are no proven treatments for preventing or delaying the onset of dementia.
Ginkgo biloba has for thousands of years been heralded by the Chinese as having medicinal properties. While today it is widely prescribed by physicians in Europe to treat both vascular and cognitive disorders, in the United States it is not yet approved for medical use by the Food and Drug Administration. Nonetheless, consumers can readily buy products claiming to improve memory that are labeled as containing Ginkgo biloba, but there are no uniform standards required of manufacturers of herbal supplements. In fact, many products marketed as Ginkgo biloba may contain none of the substance. At present, there are no federal regulations to monitor the safety and marketing claims of this growing and lucrative nutritional supplement industry.
"This study is important for many reasons, chief among them is to determine if Ginkgo biloba can indeed prevent the pain and suffering of dementia for future generations. Only a carefully designed study of this magnitude can determine if it is truly beneficial and should be recommended for its potential to prevent dementia and other problems associated with aging," said Steven T. DeKosky, M.D., principal investigator of the study as well as professor of psychiatry, neurology, neurobiology and human genetics and director of the Alzheimer's Disease Research Center at the University of Pittsburgh School of Medicine.
According to Richard L. Nahin, Ph.D., M.P.H., NCCAM Director for Extramural Research, Training and Review, "If Ginkgo biloba extract is found effective, thousands of individuals at high risk for developing dementia will have an inexpensive and safe prevention option. However, if the extract is ineffective or unsafe, these data will provide important information to health consumers as they consider continued use of this herbal product."
Participants in the study will be randomly placed into one of two groups. Half will take 240 mg of Ginkgo biloba of defined purity; half will take a placebo (an inactive sugar pill). Each group will take two pills a day for up to five years. Neither the participants nor the researchers will know if the pills are Ginkgo biloba or a placebo while the trial is in progress.
In order to qualify for the study, participants must be age 75 or older and in generally good health. Each participant will be required to identify an individual to serve as a proxy -- someone who sees the participant on a regular basis -- in order to provide researchers with information about any changes in habits, behavior or memory. Those who qualify for the study will visit the University of Pittsburgh Bellefield Clinic in Oakland for various health and memory/cognitive screenings when they are first enrolled and every six months for up to five years.
"The prevention of memory problems and dementia must be a high priority," said Lewis H. Kuller, M.D., Dr.P.H., director and chair of the department of epidemiology, University of Pittsburgh Graduate School of Public Health. "The GEM Trial offers an excellent opportunity to contribute to a ‘first’ attempt to prevent memory loss and dementia. This trial can be successful only with continued support. Participants will be at the forefront of this most important research."
For more information about GEMS, please call 1-800-872-3653.