Much Ado About Blood Test for Alzheimer's Disease

Contributed by: Dennis Fortier, President, Medical Care Corporation

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The general press is widely reporting today on a blood test for predicting Alzheimer's Disease (AD). The media coverage is based on a study conducted at Georgetown University Medical Center and published in Nature Medicine. Despite the intense focus, there really may be very little news in this story.

It is unclear why CNN would report this as a "first-of-its-kind" study, when dozens of such studies have been presented and published over the last decade (we wrote in this space about one from Johns Hopkins and another from Scripps). Past studies have been based on various, different elements in the blood but have, in some instances, shown similar levels of predictive accuracy. This study was certainly among the most accurate, but even these results need to be considered in the context of how AD progresses

In terms of AD progression, there seems to be a fairly low level of appreciation, among health reporters, about the underlying nature of the disease. To suggest that we can somehow predict sudden and stark symptoms that mark the beginning of AD, is to ignore decades of research showing that pathological changes associated with the most common forms of the disease, progress slowly for decades before damaging the brain enough to produce symptoms. At best, this new blood test might give insight that a person is in that long, variable process. But bear in mind, autopsy data show that nearly everyone has AD pathology in the brain after age 65, though most do not have any AD symptoms. Therefore, a test to detect what we currently believe to be the pathology, just isn't yet very informative.

Furthermore, a new blood test that suggests those pathological changes are underway is great, but physicians can already detect such murky signs in many ways (MRI scan, spinal tap, PET Scan, etc.). Blood tests have general advantages in terms of cost and convenience, so the reported accuracy of this test is certainly a welcome step forward. But it probably doesn't provide a lot of new insight about whether or not  a person is progressing toward the symptomatic stage of AD.

Finally, the fervor from the ethicists about the moral dilemmas associated with AD diagnoses, is misplaced. If some society wants to make a universal decision about whether or not every citizen should or should not have access to such tests, then the ethicists should weigh in. In our society, where people can decide for themselves if they wish to see a doctor and complain about a symptom, there really is no moral dilemma: those who want information will seek out such tests, and those who do not, will not.

The Case For Alzheimer's Research

Contributed by: Dennis Fortier, President, Medical Care Corporation

The case for funding Alzheimer's research, and for participating in such research,  is a compelling one.

You've all heard or read the numbers: more than 5 million Americans diagnosed, probably at least that many in early stages and not yest diagnosed, with all numbers approximately tripling by 2050.  Neither our health care system nor our society can absorb the looming impact of this epidemic.

In this excellent opinion piece posted at CNN, Dr. Ronald Petersen of the Mayo Clinic describes an approach to averting a national, disease-driven crisis.  I encourage you to click through and read it.

Larry King: Alzheimer's Special

Contributed by: Dennis Fortier, President, Medical Care Corporation

Many of you may have seen Larry King's CNN special last night on Alzheimer's disease.  It was a one-hour special report on the urgency of the challenge this disease poses for our aging population, for our health care system, and for our society.

Overall, I thought there was a fair amount of good information presented.  The expert testimonies from Dr. Ron Petersen at the Mayo Clinic and Dr. Jeffrey Cummings from the Cleveland Clinic were excellent and clearly characterized the nature and the magnitude of this epidemic.  Heartfelt stories from care givers brought a very personal face to the disease and provided an in depth look at the way this disease can affect an entire family.

Having said that, I also thought the show performed one major disservice to the public.  There was much dramatic emphasis on the fact that Larry King and Ron Reagan visited the Cleveland Clinic to be evaluated for early signs of Alzheimer's and Ron Reagan chose to forgo an evaluation based on his preference to remain "blissfully ignorant".

To be clear, everyone has the right to make such a decision and I don't begrudge Reagan his right to do so.  However, he couched his decision against the backdrop that "there is no cure" and implied that it is therefore better "not to know" about the early presence of disease process.  This is a myth we need to stop perpetrating and Larry King missed the opportunity to set the record straight.

While there is no cure for Alzheimer's disease, there is certainly treatment.  Importantly, some people respond remarkably well to treatment, adding years of independence to their lives.  Broadcasting the message that it is "better not to know", as King did last night,  may prevent some people from gathering the facts and making a more informed decision,based on the knowledge that early intervention and appropriate treatment could be significantly beneficial.

Worried About Your Memory? Maybe You Just Need to Sleep Better

Contributed by: Dennis Fortier, President, Medical Care Corporation
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We say it over and over; many common conditions cause memory loss.

Some minor forgetfulness, like inability to recall a particular word or entering a room and forgetting why, is pretty common, even in healthy people over the age of forty.  However,  more severe symptoms may indicate the presence of an underlying medical condition.  Among the many known causes of memory loss, all can be treated with some degree of success, and most can be completely cured.

While we often mention depression, medications, and thyroid disorders among the very treatable causes of memory loss, sleep disorders should also be on that list of common and treatable conditions.  A great article about this very topic was posted today on CNN's health blog, the Chart.

Sleep apnea, or interrupted sleep due to lapses in breathing, is fairly common, especially in middle-aged and older men. It can be diagnosed with high certainty in a sleep study, and generally treated with good results.  If untreated, sleep patterns can severely degrade, and chronic sleep deprivation can significantly impair alertness and cognitive function.

Given the prevalence of sleep apnea and other sleeping disorders, many worrisome signs of memory loss may be attributable to these treatable conditions.   Please keep this in mind if you are worried, or know someone who is worried about their memory, and may not be sleeping well.

Alzheimer's Diagnostic Accuracy: Theory vs. Reality

Contributed by: Dennis Fortier, President, Medical Care Corporation
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The reports on diagnosing Alzheimer's disease are maddeningly conflicting.

Research in academic journals makes it clear that a primary care physician can achieve a high level of diagnostic accuracy by following published guidelines.  However, journalists report every day that Alzheimer's disease can only be definitively diagnosed with an autopsy.  So which is it?

It turns out that both statements are correct.

Definitive vs. Clinically Acceptable
It is technically true that an autopsy is required for a "definitive diagnosis".  However, in the world of practiced medicine, we rarely operate with definitive diagnoses for any disease or condition.  Instead, we rely on "clinically acceptable" diagnoses that are accurate about 85%-95% of the time.  The emphasis on "definitive", or 100% accuracy, is actually quite misleading since it establishes an unrealistic standard that is rarely met in the real world of medical practice.

As for the academic perspective, a clinically acceptable level of accuracy is indeed achievable by following published guidelines.  These guidelines involve a complete medical history including a review of medicines, neuro-psychological assessment, blood tests, and an MRI or CT image of the brain.  In some cases, a PET scan of the brain might also be required.

Diagnostic Guidelines
To paraphrase the guidelines: if a patient shows impaired short-term memory as well as impaired cued recall, is not taking any medications known to disturb memory, is not abusing alcohol or other drugs, is not depressed or suffering from anxiety, does not have any apparent or detectable infections, has no uncontrolled diabetes or hypertension, has a properly functioning thyroid and no particular vitamin deficiencies, has not suffered a recent head trauma, and has no evidence of strokes or tumors in the brain, then the physician can be quite confident that the patient has Alzheimer's disease.

Essentially, the hallmark forms of memory impairment need to be objectively confirmed by cognitive assessment, and other known causes of such impairment ruled out.  A family history of Alzheimer's disease, or a genetic test showing a particular predisposition, would add confidence to such a diagnosis.

Why the Different Perceptions?
The reason for the stark difference in the academic perception of diagnostic accuracy and the journalistic perception of diagnostic accuracy is "lag".  In this case, lag refers to the well documented time-gap between medical advance and implementation of medical advance.  In other words, medical research leaps forward much faster than physicians can learn about and implement new findings and guidelines.  Right now, there is a significant gap between best practices in the field of memory loss and the actual practices that physicians are using in their clinics.

Half of Alzheimer's Cases Misdiagnosed
Recent articles from CNN and WebMD have reported that about half of Alzheimer's cases may be misdiagnosed in clinics.  Oddly, this probably indicates progress from recent years when memory problems went largely undiagnosed and ignored, to current times when many memory problems are being improperly attributed to Alzheimer's disease.  Progressing from "doing nothing" to "doing the right thing half the time" is actually a favorable development.

With time, our over-worked physicians will gain a better command of emerging guidelines.  This will improve their collective ability to recognize problems and to accurately determine their cause before prescribing treatment.

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A better understanding and more awareness of Alzheimer's related issues can impact personal health decisions and generate significant impact across a population of aging individuals. Please use the share button below to spread this educational message as widely as possible.

Can You Prevent Alzheimer's Disease?

Contributed by: Dennis Fortier, President, Medical Care Corporation
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While we have no sure fire approach to preventing Alzheimer's disease today, each of us can meaningfully lower our own risk of suffering from Alzheimer's down the road.

Some important risk factors, like age and genetics, are beyond our control. Others, such as our physical fitness, our diet, our cardio-vascular health, our management of other medical conditions, and the degree to which we stay intellectually and socially engaged, are all directly affected by our life style choices.

A great summary of preventative advice was published this week as an opinion piece at CNN. While such articles are commonly propagated online by merchants selling unvalidated supplements or brain-exercise programs, this one stays within a message that is well supported by scientific evidence.

Other good online sources of Alzheimer's prevention information are the non-commercial websites PreventAD.com and OCVitalAging.org.
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A better understanding and more awareness of Alzheimer's related issues can impact personal health decisions and generate significant impact across a population of aging individuals. Please use the share buttons below to spread this educational message as widely as possible.