More than 5 million Americans have Alzheimer’s disease, and in spite of a worldwide effort to find a cure, our mildly effective therapeutic options remain limited to treatments to slow down the disease. While the search for better treatments goes on, many scientists are looking for treatments to prevent the development of AD.
Therapies that prevent disease, like vaccines, are called primary prevention. Measles, mumps, and rubella are essentially diseases of the past (at least in the United States) because our children are vaccinated at an early age. Unfortunately, a vaccine for AD is still far off.
Recently, some researchers have turned their attention toward primary prevention for AD. That these studies are being conducted at all is exciting, as primary-prevention trials are notoriously difficult to set up and manage. Primary-prevention trials require a large number of people to participate for years at a time. Once you have people in the trial, it’s often a challenge to retain them. Some get bored, others move, and still others have more pressing family obligations. Nevertheless, because of these people, we are beginning to get a better idea of what might and what definitely does not prevent AD.
One trial that started with a lot of hope and ended up with negative results was the Women’s Health Initiative. Prior to the WHI, the accepted view among physicians was that estrogen therapy reduced a woman’s risk of developing cognitive impairment. Unfortunately, the opposite proved to be the case: Women who took estrogen had a slightly higher rate of cognitive impairment than women who didn’t.
On the alternative medicine side, there’s currently a trial of over 5,000 people to see if ginkgo biloba will prevent AD. The study is about halfway done, and in another three years we will be able to see if ginkgo biloba does make a difference or if it is just another example, like estrogen, of hope getting ahead of science.
So, when it comes to primary prevention for AD, we’re not there yet. However, there are lots of good scientists and an even larger number of generous volunteers who are trying to change that. For those who face the daily challenges of having a loved one with this tragic disease and maybe worrying about developing the disease themselves, it is reassuring to know that these primary-prevention trials may lead to effective ways to prevent AD.
Robert W. Lash, M.D. is an associate professor of internal medicine at the University of Michigan Medical School. His clinical interests include thyroid disease, diabetes, endocrine disorders in pregnancy, osteoporosis and metabolic bone disease, and medical education. A member of the LLuminari team of experts, a board certified internist and endocrinologist, Dr. Lash has an active clinical practice at the University of Michigan.