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Alzheimer's and PET Scans: When a Predictive Diagnosis Is Not Necessarily a Good Thing

01/05/2012 03:34 pm ET | Updated Mar 06, 2012

What if a medical test was available that could predict your future? What if you could know with absolute certainty that a decade from now you would be diagnosed with a serious disease? Would you take this test?

Logic would dictate that the answer would be yes. Why not? Ten years gives you time to make a variety of changes that might alter the outcome or, at the very least, help you make the necessary preparations in order to cope with the disease. The idea sounds a bit futuristic, yet this test is close to existing now for Alzheimer's and Chronic Traumatic Encephalopathy (CTE), and I'm going to argue that most of us, if given the choice, wouldn't go anywhere near it.

Until now, autopsies provided the only conclusive proof that what was observed -- the memory problems, erratic emotional states, depression and, in the worst cases, loss of one's sense of self -- was, in fact, caused by the brain's circuitry becoming "gunked up" with plaque made of protein Amyloid-beta. This is why the new use of a Positron Emission Tomography (PET) scan is so important; it confirms the presence of the disease process before one exhibits symptoms.

CTE has received a great deal of media attention over the past few years as more football and hockey players whose symptoms, due to the concussive nature of their sports, mimic the same symptoms seen in Alzheimer's patients. In fact, autopsies of diseased players showed the same level of plaque buildup as the brains of people who had Alzheimer's.

A number of research labs around the world, including teams in Britain, Germany, Australia and Texas, are using PET scans both to confirm and predict Alzheimer's. Software technology developed by researchers at the Center Hamburg-Eppendorf, in Germany, even makes it simpler for nonprofessionals to understand the results. According to Ralph Buchert, a scientist at the center, "a novice supported by the system should perform at a similar level to an expert." This would allow for scans to be more available for use. As evidenced by the work of these researchers, the soft science of interviews and cognitive tests will become secondary to the hard science of PET scans and other imaging technologies.

Despite this advancement in diagnostic technology, the picture is not completely rosy. While these developments are critically important, they don't address the issue of treatment. To date, there are no drugs that will stop, prevent or consistently slow the course of these diseases.

Once the illness begins, it is inexorable. Anybody who has watched a family member morph into a psychologically unrecognizable person understands the destructive power that is unleashed.

Let's imagine the following scenario:

You're 55, it's time for your annual checkup and, in addition to the chest X-ray, EKG and blood work, your doctor tells you that a scan is now available to assess any preliminary buildup of plaque in your brain. Your internist says that, "just like the X-ray checks for spots on your lungs, it's a good idea to have this PET scan."

Would you take the test? Keep in mind that, with the exception of a senior moment now and then, you have no symptoms. The question is rhetorical. The terror waiting for the results would be unbearable. It would be easy to rationalize not taking the scan by convincing ourselves that we are and will continue to be healthy.

In reality, this scenario is highly unlikely. PET scans will not be used routinely since insurance companies are not in the business of paying to treat an illness that is hypothetical. Moreover, since treatment options are not available, the issue is moot. Yet, there is one group for which this scan could be incredibly useful now -- NFL players. No other athletes live with the subliminal dread that haunts professional football players as they age. By now, we're all aware of the relationship between playing football (and, to an extent, hockey) and the increased probability of serious cognitive problems later in life.

Another concern for football players is that concussions might not be the only factor that lays the degenerative groundwork for CTE. The sub-concussive head banging that occurs continually over the course of a player's career may also contribute to CTE. In other words, any player who never had a diagnosed concussion may still be susceptible to this terrible disease.

Given the aforementioned advancements of PET scans, something along the lines of the following would be useful for the NFL: initiate a protocol in which every player (with the exceptions of kickers) takes a PET scan and agrees to follow-up scans every three years for the rest of their life.

Not only would this provide critical information to the players both during and after their careers, but it would also provide an enormous amount of longitudinal data for researchers studying CTE, concussions and cognition. It's an ideal research laboratory, and the NFL could easily absorb the costs.

Unfortunately, the probability of both the league and the players' association agreeing to such a proposal is slim. The players are not going to be keen of becoming aware of early damage to their brains, and the league certainly wouldn't want anyone to know. Given how long it took for the NFL to establish treatment guidelines for concussions, this proposal stands no chance at all. One can easily imagine NFL Commissioner, Roger Goodell, continuing to channel the tobacco industry CEOs of the 1960s by arguing that the science is insufficient, and we should wait before subjecting our players to unnecessary medical tests.

With the exception of athletes who play impact sports, there is some good news for the rest of us. While genes play a critical part in the evolution of Alzheimer's, healthy lifestyle choices can significantly reduce the risk of developing the disease. Not surprisingly, the same kinds of choices that keep your heart healthy will, simultaneously, support the brain. These include: eating right, exercising, quality sleep, managing stress and staying mentally and socially active.

That being said, lifestyle management can only go so far and once diagnosed, the use of drug treatment for Alzheimer's and CTE is critical. Without treatment catching up to diagnostic technologies, the waiting rooms for PET scans screening for the first tangled threads of these diseases will be essentially empty.

I don't plan on being in that waiting room either.

For more by Lloyd Glauberman, Ph.D., click here.

For more on Alzheimer's disease, click here.

For more on new research, click here.