Slowing Alzheimer's before symptoms appear
The treatments now available for Alzheimer’s disease are like Band-Aids, says Emory neurologist James Lah.
They treat the symptoms but not the underlying pathology. At best, they slow Alzheimer’s progression by only six months.
But Lah and his colleagues in the Emory Alzheimer’s Disease Research Center (ADRC) are working to change that. The center, recipient of the National Institute on Aging’s ADRC designation and $8 million in funding, is the only such center in Georgia and one of only 30 in the nation.
For Georgia patients, that means access to clinical trials in Alzheimer’s that are showing promise in delaying onset of the disease. Lah leads the clinical core of Emory’s ADRC, which recruits participants and provides data on patients with Alzheimer’s and other memory problems, as well as healthy people in control groups, to facilitate research.
For example, Emory is one of 12 universities participating in a nationwide study testing the effectiveness of an experimental medication, CERE-110. The phase 2 study is the first gene therapy clinical trial for Alzheimer’s. It seeks to prevent or slow the death of brain cells in Alzheimer’s patients by delivering a protein known as nerve growth factor (NGF) directly to the affected area of the brain.
NGF nourishes a specific population of brain cells that deteriorate in Alzheimer’s. These cells produce a chemical, acetylcholine, which plays a vital role in memory and cognitive function. If NGF can keep these cells alive and healthy, then levels of acetylcholine won’t drop as dramatically, leaving memory and cognition intact.
While current therapies try to stop the chemical breakdown of acetylcholine, CERE-110 holds the promise of keeping the cells that make the chemical healthy. “This is one of the most exciting first steps to rescue brain cells that we know are important in memory and thinking and that deteriorate in Alzheimer’s,” says neurologist Allan Levey, who directs the Emory ADRC.
The Emory researchers also are trying to intervene with Alzheimer’s before symptoms appear. The course of Alzheimer’s typically spans 30 years. By the time the first mild symptoms of memory loss appear, the disease already has been wreaking havoc in the brain for about 20 years. Catching the disease earlier would give treatments a better chance.
To that end, Lah has developed an inexpensive screening test for mild cognitive impairment (MCI), often the earliest stage of the disease. Traditional screening tests take up to 60 minutes to complete, but this test is brief, consisting of a three-minute cognitive screening test and a functional activities questionnaire that is filled out by someone close to the patient. The test so far picks up MCI from 80% to 85% of the time and MCI plus undiagnosed dementia closer to 95% of the time. It the test holds up through validation, it will be an inexpensive, quick tool for physicians to use to screen for early stages of memory loss.
Such interventions and tools can’t come soon enough. More than 5 million Americans have Alzheimer’s. With the great wave of baby boomers approaching the Alzheimer’s prone years, Levey expects a tsunami of new cases—up to 115 million worldwide by 2050.
“To tackle the epidemic that is coming down the road, early detection is critical,” says Levey. “A simple, quick screen would be a big advantage and could identify Alzheimer’s earlier when treatments are more likely to be effective.” —Martha McKenzie