New Alzheimer’s drug for diagnosis on horizon

Published 1:09pm Tuesday, March 22, 2011

While heart disease remains the number one killer of Americans, there is less fear about having heart-related illness than there is about receiving a diagnosis of Alzheimer’s disease.

There are many reasons that heart disease may concern us, but most don’t dramatically raise our fear levels. Most of us know that heart disease, in many cases, is preventable and treatable. So going to the doctor for simple tests and related exams often gives us a head start on knowing about, preventing or treating heart disease.

That’s not the case with Alzheimer’s disease – at least not yet.

Alzheimer’s disease remains an incurable brain disease that cannot be 100 percent accurately diagnosed, particularly in its earlier stages, because its signs and symptoms often mask or mimic other physical or mental problems such as depression, small strokes or prescription drug reactions.

Today, neurologists and physicians who treat dementias such as Alzheimer’s do a very good job of diagnosing the disease, but there is room for error and therefore, improvement.

Confirmation that a person has Alzheimer’s disease can only be totally assured by analyzing samples of brain tissue of a patient, and that can only be done after the death of the patient, during an autopsy. However, that may soon change.

Stated very simply, Alzheimer’s disease is caused by plaque build-up in the brain, analogous to cholesterol building and blocking vessels to the heart.

In the case of Alzheimer’s the plaque interferes with the brain’s ability to send signals and information from one part of the brain to another part of the brain or to various nerves and muscles throughout the body.

For instance, if the brain’s storage area for memories of families and names of people is blocked by plaque, it may have the information you need and want, but cannot access the path to get the information out.

The net result is the patient saying, “I can’t remember” but the truth is that the connections between parts of the brain are blocked by plaque in the brain.

To treat any disease, an accurate diagnosis is needed, and one of the tools we have available today to help diagnose changes in the brain is a radiology tool called a PET scan, a machine that takes digital images of the brain. The problem has been that there hasn’t been a way to highlight plaque specific to Alzheimer’s disease to absolutely confirm that diagnosis, particularly in early stages – until recently.

In January, an advisory committee to the Food and Drug administration reported on findings submitted by Avid Radiopharmaceuticals, makers of a dye that specifically highlights the plaques caused by Alzheimer’s.

The advisory committee approved the use of the dye in conjunction with a PET scan to enable the scan to show the characteristic plaques of Alzheimer’s disease in the brain of a living person.

Remember, plaques are part of the criteria for having Alzheimer’s — if a person with memory problems does not have plaques, that person does not have Alzheimer’s. But without the scan, the only way to know if plaques are present is a post mortem autopsy.

This new dye is great news, but before being approved by the FDA there remain months of testing and establishing the procedures for radiologists agreeing on what the scans say as well as training doctors in how to read the scans. But in most cases, the FDA does follow the advice and recommendations of its advisory committees.

Future use of these scans could be very valuable in diagnostic situations when it’s not clear whether a patient’s memory problems are a result of Alzheimer’s disease or caused by something else. If a scan shows no plaque, the problems are not caused by Alzheimer’s and could be from tiny strokes or other diseases.

Unfortunately as of today, if a person has Alzheimer’s, there are few treatments that can slow the progressive nature of the disease and none that can reverse or cure it. There is a great deal of worldwide research under way looking for new drugs that are intended to reduce plaque and for treatment of the disease.

With over 5 million Americans currently diagnosed with Alzheimer’s disease, and almost 80 million baby boomers turning senior over the next 18 years, we can expect to see the number of Alzheimer’s cases skyrocket.

Wouldn’t it be wonderful to have a simple procedure to definitively diagnose such a frightening disease? Let’s hope that Avid’s new PET scan dye passes its final tests and is approved for diagnostic purposes by the FDA very soon.

Ron Kauffman is a Geriatric Care Manager and Certified Senior Advisor. He is the author of Caring for a Loved One with Alzheimer’s Disease, available at www.seniorlifestyles.net. He can be reached by email at drron407@bellsouth.net.

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