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Entries in Amyloid (2)

Thursday
Aug302012

Future of Alzheimer's Battle Lies in Prevention, Doctor Says

iStockphoto/Thinkstock(NEW YORK) -- First-degree relatives of adults with Alzheimer's disease have a higher lifetime risk for developing the condition than those without a family history.  However, there is currently little that these relatives can do that is proven to lower their risk of developing the disease later.

It is this problem that Dr. Sam Gandy, professor of Alzheimer's disease research at Mount Sinai School of Medicine, believes will be addressed sooner rather than later.  And he says a new study published in the New England Journal of Medicine Thursday may set the stage for Alzheimer's prevention studies in the near future -- studies that may have more implications for the children of patients than for the patients themselves.

The new study looked at adults who had a genetic form of Alzheimer's but had not yet displayed symptoms.  Interestingly, researchers found that changes in the levels of a protein associated with Alzheimer's, called amyloid, can be detected up to 25 years before symptoms begin.

In an editorial accompanying the new study, Gandy explains why this matters.

"I think this study sets the stage for prevention studies," Gandy tells ABC News. "The only way to know how important amyloid is is to prevent it from forming altogether."

The editorial comes at a time when the potential role of amyloid in Alzheimer's is a topic of growing controversy.  A number of trials for amyloid-lowering drugs failed to show any benefits in patients with mild Alzheimer's.

Gandy argues that these recent drug trials were started too late.  Instead, he argues, new studies should target Alzheimer's prevention, ideally decades before patients show any signs of the disease.  

Hypothetically, the trials could target adults in their 40s and 50s with a family history of the disease.  If a safe amyloid-lowering drug was available, first-degree relatives could potentially get a trial of the drug, and researchers could monitor these individuals to see if they developed Alzheimer's or not.

Most Alzheimer's experts contacted by ABC News agree that the new data is promising.

"In my view, the editorial is precisely on target," says Dr. Paul Aisen, director of the Alzheimer's disease cooperative study at the University of California San Diego.  "This is an important message to share with the scientific community and with families affected by [Alzheimer's] who are discouraged by the disappointing results of large anti-amyloid trials conducted in individuals with dementia."

"Ultimately, to make a real impact, we have to focus on prevention," says Dr. James Galvin, professor of neurology and psychiatry at New York University Langone School of Medicine.  "This means identifying markers of disease to initiate effective treatments before symptoms begin.  Waiting until someone already has memory loss suggests that there is already substantial damage to vital brain systems."

Some experts, however, were more skeptical of the editorial's message.  Specifically, they question whether amyloid is really the true or only culprit behind Alzheimer's -- and whether focusing on it so heavily may close the door too early on exploring other potential factors behind the disease.

"The danger is that if we rely only on the amyloid hypothesis for developing treatment, we might miss other opportunities," says Dr. Zaven Khachaturian, president of the Prevent AD 2020 Campaign.

Copyright 2012 ABC News Radio

Monday
Apr092012

A New Way to Detect Alzheimer’s?

iStockphoto/Thinkstock(NEW YORK) -- A new drug may help doctors give patients suffering from Alzheimer’s-like symptoms some clarity they desperately want: a conclusive diagnosis.

On Friday, the FDA approved Eli Lily’s Amyvid to help doctors determine whether patients have Alzheimer’s disease.

Until now, a definitive Alzheimer’s diagnosis has only been possible after a patient has already died since the only known method of detection involves cutting into the brain and taking samples to look for the presence of a protein called amyloid. Doctors are left to base their diagnoses on symptoms of Alzheimer’s alone.

The new drug acts by binding to amyloid plaques in the brain, allowing them to be captured in a type of imaging test called a PET scan.

“In my opinion this is very big news,” Dr. Michael Weiner, director for the Center of Imaging of Neurodegenerative Diseases at the University of California, San Francisco. “Now for the first time, using this agent, we can identify the amyloid plaques in the brain of living people."

“This allows us to determine who has Alzheimer’s disease in their brain and who does not,” he said.

The number of people diagnosed with Alzheimer’s dementia has doubled in the last few decades; an estimated 5.4 million Americans currently live with the disease. Alzheimer’s is currently the sixth-leading cause of death in the United States, and mortality rates are on the rise.

While this new drug may help doctors identify patients who may have Alzheimer’s disease, there is some debate as to how useful the information revealed by the use of the drug will be.

Part of the problem, says Dr. Clifford Saper, chairman of Neurology and Harvard’s Beth Israel Deaconess Medical Center, is that most people older than 80 have some level of amyloid in their brains, and the amount of amyloid present doesn’t necessarily indicate whether the patient has the disease or not.

Plus, he added, practical applications are still a pipe dream, at least for now.

“There is no change in the care of most patients based upon knowing this information, as we have no specific treatment for Alzheimer’s disease,” he says.

The prevalence of amyloid in the brains of many elderly people may also lead to a new flood of positive scans -- which in turn may lead to over-diagnosis of Alzheimer’s.

“[Amyvid will] raise false hope and increase costs,” says Dr. Peter Whitehouse, a professor of neurology at Case Western University.

With spending on Alzheimer’s disease already topping $130 billion annually by Medicare and Medicaid alone, the question remains whether government or private insurers will pay for the Amyvid diagnostic test since it comes with a significant price tag.

Nevertheless, while there are currently no treatments shown to slow the progression of Alzheimer’s, there is clinical testing underway now for several potential treatments. Once one becomes available, amyloid imaging could help doctors better select patients for treatment and to monitor effectiveness. In fact, Amyvid is already being used for these purposes in ongoing clinical research.

But until new treatment options become available, Amyvid’s use will likely be limited to helping doctors rule out Alzheimer’s disease in patients with dementia.

Copyright 2012 ABC News Radio







ABC News Radio