Should We Screen Older Adults for Cognitive Impairment?

The US Preventative Services Task Force (USPSTF) recently addressed this question and determined that there is “insufficient evidence to assess the balance of benefits and harms” associated with such screening. In effect, they could not conclude if it was helpful, harmful, or neither.

However, the question, and the conclusion of the USPSTF, both lend themselves to widespread misinterpretation. This brief summary takes a precise look at the issue and offers some clarity.

First of all, the task force defines “screening” in a very specific way. In this case, it means assessing the cognition of  individuals with no clear signs or symptoms of a cognitive deficit. There is essentially no debate that doctors should evaluate the cognitive health of patients who do show signs of impairment; the USPSTF would agree. But “evaluating symptoms” is not the same as “screening” and is therefore, not a part of this discussion.

Assessing subjects with no symptoms is “screening” while assessing subjects who do have symptoms is “case finding”. This USTFPS opinion relates strictly to screening.

Second, the term cognitive impairment covers a wide range of disability from very mild (a subtle sense that thinking skills are becoming slower or less vital) to severe (full dementia including a loss of ability to care for oneself). The broad range of severity in this definition is problematic because, as just discussed, the term “screening” only applies to those “older adults” at the extreme mild end of this spectrum. As such, the posed question contains an inherent flaw. Either “screening” is the wrong word because it does not apply to many along the spectrum of cognitive impairment, or the term “cognitive impairment” must be precisely qualified to include only asymptomatic subjects. Otherwise, a sensible answer cannot be derived.

Finally, this discussion is further complicated by the fact that the publications, upon which the USPSTF based their conclusion, evaluated only cognitive assessment instruments designed to detect “dementia”, not the asymptomatic subjects contemplated by the notion of screening. Therefore, an evaluation of the benefits and harms of screening older adults for the full range of cognitive impairment, based on instruments that reliably detect only the most severely impaired, is neither comprehensive nor conclusive.

The bottom line, as emphasized in the accompanying editorials to the USPSTF recommendations published in JAMA, is that wide scale screening of asymptomatic populations over age 65 is not yet warranted by published evidence, but it certainly has strong theoretical appeal. 

The USPSTF’s conclusion of “insufficient evidence” should not be interpreted as a recommendation against screening, rather, it is a factual statement about the paucity of studies that have been published in this area. But it should be noted that Medicare mandates the “identification of cognitive impairment” during Welcome to Medicare exams. So when asking if we should screen older adults for cognitive impairment, at least one well-informed branch of government believes that the benefits outweigh the costs.

3 Stages of Alzheimer's Disease

Contributed by: Dennis Fortier, President, Medical Care Corporation

Alzheimer's disease was clarified today.

With the announcement of new diagnostic guidelines, developed in tandem by the National Institute of Aging and the National Alzheimer's Association, we can now conceptualize the disease across a continuous spectrum with three contiguous stages of progression.  There is a pre-clinical stage, a mild cognitive impairment stage, and a dementia stage.

Pre-clinical Stage
The purpose of defining this very early stage, before the presence of any clinical symptoms, is purely to benefit research.  While there are no symptoms of disease in this stage, researchers have noted that certain biological changes, including protein levels in the brain, blood, and spinal fluid, seem to change in fairly predictable ways during the years before Alzheimer's patients manifest symptoms.  The changes are not sufficiently telling to diagnose the disease at this early stage, but identifying these individuals and enlisting them as research subjects is an important goal for the field.

Importantly, physicians will not use these criteria to diagnose such early stage Alzheimer's. The definition of this stage is purely to help researchers speak a common language about similarly characterized research subjects. 

Mild Cognitive Impairment Stage
In this stage, patients have clear underlying pathology consistent with Alzheimer's disease, and have also developed clinical symptoms of memory loss or other cognitive deficits.

The identification of this stage is the most important aspect of the new guidelines, as it will enable earlier intervention for patients who are, almost certainly, in the progressive throes of Alzheimer's, but still have relatively healthy brains.  It is hoped that existing treatments, and new treatments in the pipeline, will be optimally effective in these early stage patents.

Dementia Stage
This stage is quite consistent with our former view of the disease.  It requires the hallmark pathology of amyloid plaques in the brain, plus cognition so impaired as to meet the criteria for dementia (two or more realms of impaired cognition that interrupt daily activities of living). In the past, we did not call the problem "Alzheimer's disease" until the patient reached this end stage condition.

How to Best Detect Early Alzheimer's Disease

Contributed by: Dennis Fortier, President, Medical Care Corporation
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Sometimes, a lot of press coverage is devoted to an interesting misinterpretation of a fact that, once correctly understood, is not nearly as interesting. This is one of those times.

Over the past week, I have seen intense coverage of a story about how friends and family are better at spotting early signs of Alzheimer's dementia compared to traditional tests that a doctor might use. This sounds great until you unpack the headline and understand the facts.

Even Mild Dementia is a Severe State of Health
The problem, as we point out often in this space, is the definition of "dementia". Even mild dementia, which sounds like a subtle condition, is actually a severely impaired state of mental health. To meet the definition of dementia, even mild dementia, a patient must be so impaired that their loss of function interferes with their occupational or social life. Demented people, even mildly demented people, cannot completely care for themselves.

Detecting Dementia does not Require a Test
With this is mind, many experts make the case (and I agree with them), that a test for dementia is not necessary. Dementia is a readily apparent condition that a friend or family member should easily recognize. The fact that doctors still use tests that cannot accurately distinguish between a demented person and a non-demented person is indicative of ineffective clinical practices.

For the record, there are newer, more accurate tests, such as the MCI Screen, that detect dementia with almost perfect accuracy. More importantly, they also identify much earlier and subtler stages of decline known as mild cognitive impairment. However, this current finding from Washington University and published in Brain, compared the ability of friends and family at spotting spot Alzheimer's dementia with the accuracy of "traditional" tests. This is a clear and damming comment about the poor accuracy and minimal utility of the "traditional" test they used for comparison, the Mini-Mental State Exam (MMSE).

In this study, input was collected with an instrument called the AD8, an eight item questionnaire that is completed, on behalf of the patient, by an informant (friend of family member). It was shown to be better at identifying demented patients than the MMSE. That is great news and the AD8 is a non-invasive tool that would be a pragmatic improvement over the MMSE in a primary care setting.

The Bottom Line
I think the most important message, buried in this recent spate of press, is that the traditional tests are not as good as the AD8 at detecting dementia, but detecting dementia doesn't really require a test. To intervene early against Alzheimer's disease, and to reassure healthy patients that their perceived memory decline is not caused by underlying disease, physicians need instruments that accurately detect mild cognitive impairment.

Advances in detecting dementia are not interesting stories, regardless of how much press they get.

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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.

Not All Strokes are Created Equal

Contributed by: Dennis Fortier, President, Medical Care Corporation
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Although physicians are fairly precise in their discourse amongst themselves, they sometimes use the term "stroke" with the lay-public to describe a wide range of occurrences in the brain. A new study published in Neurology suggests that we might all benefit from the practice of more carefully characterizing one form of stroke from another.

In a study at Columbia University, researchers looked at brain scans of 679 subjects aged 65 and older and compared those with white matter hyperintensities to those with areas of dead brain tissue. The first group had suffered what is sometimes called "mini-stroke" and were more than twice as likely to have mild cognitive impairment with memory loss compared to the latter group of stroke victims that was more likely to have mild cognitive impairment without memory loss.

The key finding was that the different events (mini-stroke vs. stroke) led to different types of cognitive problems. While mini-strokes and strokes have traditionally been considered as originating from the same source, this study suggests they might be quite different.

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.

How to tell if MCI will convert to Alzheimer's Disease?

Contributed by: Dennis Fortier, President, Medical Care Corporation
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I commonly encounter this question in the press, I hear it discussed at conferences, and physicians pose it to me on a regular basis. Despite the centrality of this question in so many forums of cognitive health, it is a nonsensical inquiry with inherent flaws. Additionally, it propagates a pernicious brand of confusion that I want to clarify today.

As per my earlier post, Mild Cognitive Impairment 101, there are many medical conditions that can cause a subtle cognitive deficit. Pondering whether or not MCI will "convert" to Alzheimer's Disease (AD) obscures the fact that MCI is a symptom of an underlying medical problem (not the problem itself). In fact, some MCI is actually caused by AD and therefore, the prospect of converting does not belong in a logical, informed discussion.

When MCI is present, the correct question is "what is the cause of the impairment?". If the answer is AD, then the folly of a conversion outcome is clear; the disease precedes the impairment and not vice-versa. If the MCI is caused by some other medical condition (depression, vascular disease, anxiety, etc.) then it is equally futile to consider whether or not it will convert to AD; these medical problems are separate and distinct. That is not to say that such a particular person will never get AD because they may. In fact, the medical condition causing their impairment might even confer a greater risk for AD, but the notion of "converting" from MCI to AD is illogical.

A good analogy would be to learn of a patient with excessive thirst and blurry vision and then wondering if these symptoms will ever "convert" to Diabetes. Most physicians would perform a diagnostic work-up, take note of the high blood sugar, and diagnose diabetes immediately. There would be no debate about whether or not the symptoms would covert to the disease -- they would conclude that the presence of the disease has caused the symptoms. We must do the same with MCI. That is, perform a work-up and identify the underlying cause of the symptoms so that the patient may benefit from timely intervention.

So why have I labeled this as "a pernicious brand of confusion"? Because the perpetration of the idea that MCI might or might not convert to AD prevents some (if not many) primary care physicians from proactively diagnosing the cause of MCI and treating it. Giving any credence to the notion that MCI is a sporadically progressive precursor to AD is a barrier to clarity and interferes with a higher standard of care in this field.