Tuesday, November 20, 2012

How the new brain scan for Alzheimer’s could help, and won’t help

There’s a powerful new Alzheimer’s diagnostic test (the new brain scan) on the block, and now we’re all going to have to decide if we want to use it or not. (My colleagues at GeriPal.org seem generally skeptical.)

This is an especially relevant question for a outpatient geriatrician like me: I’m often confronted with the complaint of memory problems, I do a fair amount of diagnosing dementia (usually on my own, with the occasional referral to a memory clinic or neurologist), and I do a lot of counseling of patients and families, usually over the span of months to years.

In other words, I field memory complaints and dementia diagnosis as they appear in the primary care clinic, and with the aging population surging into Medicare, I essentially do what front-line generalists will need to do for millions of elders over the next 10-20 years.

So would I order this scan, for someone with memory problems? How would this help or hinder me, and the families I’m trying to help? What kinds of benefits and harms will we get for the extra cost of this test, given that there is currently no cure for Alzheimer's and not even any reliable ways to slow the progress of this devastating disease?

A  recent NY Times article highlights these questions, and features some of the first private patients to have the new scan. It’s a good story, and if you haven’t read it yet, you should.

But it’s the story of trying to confirm the presence or absence of Alzheimer’s disease.

Whereas in my world, the story is about how to help people with memory impairment. Which is not quite the same story, and involves slightly different questions. In particular, I don’t just think “Is it or is it not Alzheimer’s?” What I think about is:

  • Is this dementia? With patients, I usually explain that dementia means developing permanent brain changes that make memory and thinking skills worse, to the point that daily life skills are affected. I then explain that Alzheimer’s is the most common underlying cause of permanent brain changes. 

  • Is anything making this person’s cognition worse than it would otherwise be? It’s especially common to find that medications (such as benzodiazepines for sleep) are making older people worse. Several other medical conditions (i.e. hypothyroidism, depression) can worsen cognition and should be checked for as well.

  • Any special neurological features that I should make note of? I briefly check for signs of parkinsonism, hallucinations (common in Lewy-Body dementia), or neurological changes suggestive of subtle strokes. But otherwise I don’t spend too much time trying to pin down the underlying dementia, unless something strikes me as distinctly odd. Overall, I find the principles of helping patients and families with dementia are basically the same for the most likely causes of dementia (Alzheimer’s, Lewy-Body dementia, vascular dementia).

The patient and family, of course, have their own questions and concerns. They certainly do often ask if it’s Alzheimer’s. But we shouldn’t answer that question too narrowly. Many people don’t understand the difference between Alzheimer’s and dementia (I’ve had people tell me “Thank God it’s notAlzheimer’s” when I broke the news of likely dementia). But overall, what scares them is the specter of progressive cognitive disability.

Most of all, in my experience patients and families want to know:

  • What is going on?
  • What should we expect for the future? 
  • Will this get worse? How fast?
  • What kind of help is there? Are there treatments?
  • How will we manage?

Back to the article. What would’ve happened to those patients if they hadn’t had the scan? And what is still left undone or unresolved after the scan?

Consider Awilda Jimenez, the woman featured at the start of the Times story, who becomes forgetful at age 61. Here’s how things usually unfold when I see someone like her:

  1. I make a preliminary assessment of cognitive abilities. I use a combination of office-based cognitive test, like the Montreal Cognitive Assessment, and asking about function, especially IADLs like finance and driving. The article doesn’t say how Ms. Jimenez scored on these (one hopes they were checked before offering her the scan), but it’s not uncommon for someone with early Alzheimer’s to score 24 on the MOCA and have problems with memory and finances.
  2. I also look for exacerbating factors, like medication side-effects, or other illnesses. Let’s assume I find none. Let’s also assume the neuro exam is generally benign (other than the thinking problems).
  3. I then explain to the patient and family that there does seem to be evidence of problems with memory and thinking. If the problems are fairly prominent, we start to discuss the diagnosis of mild dementia, and that it’s probably Alzheimer’s. If the problems are subtle and things feel inconclusive to me, or if the family wants more evaluation, we talk about referring for neuropsychological testing, to get further insight into the cognitive problems.
    • Let’s say the neuropsychological testing comes back indicating deficits; a common conclusion is that the findings “may be consistent with an early dementia such as Alzheimer’s.” Then I get to explain to patient and family that it’s probably dementia, probably Alzheimer’s, could be vascular or another, generally slowly gets worse but occasionally seems to stop
  4. Let's see how this evolves. I almost always end up telling families that we will need to see what happens over the next 6-12 months. 
  5. Practical strategies for right now. I coach families on avoiding psychoactive medications and other common causes of delirium. I also encourage them to look for dementia support groups, and try to point them towards resources for learning more about living with dementia.

In other words, as things currently stand, evaluating memory impairment in someone who’s early in the dementia process often ends up with our telling patients that they probably have something bad: mild dementia, most likely Alzheimer’s.

This uncertainty is frustrating for clinician and patient. (It’s even worse when the deficits are in the range of mild cognitive impairment, or in that “is this affecting daily function?” gray area.) So it seems that the new brain scan should be a boon, with its ability to give a definite yay or nay on whether Alzheimer’s is present.

Today, patients and families can cling to the hope that maybe it’s not Alzheimer’s, maybe it won’t keep getting worse, maybe it’s something else. I have seen patients and families resolutely set aside the possibility of Alzheimer’s (why dwell on the possibility of something horrible coming into your life), and other families obsess over the issue for months. 

Regardless of which approach they take, in most cases, the cognition keeps getting slowly worse, and 1-2 years later the family is enmeshed in caring for someone who has become quite cognitively disabled. At that point, they are trying to survive and we clinicians are trying to help them maintain the best quality of life possible.

Back to the new scan. I would briefly summarize the benefits and burdens as follows (for patients in the mild/early stage of symptoms): 

  • Reduces period of clinical uncertainty for those patients who in fact have Alzheimer’s.
    • With a positive scan, families could more quickly move into grieving, acceptance, and hopefully planning for the upcoming challenges. (Engagement!)
    • Although there is no cure and drugs don’t tend to delay progression very much, clinicians can and should focus on the many ways to optimize the person’s function. Caregivers can focus on getting from coaching and support. Other clinicians should be alerted to the diagnosis and modify their work accordingly.
    • A negative scan in someone with symptoms would presumably spur a search for the real problem.
  • Takes a fair bite out of the payor’s wallet. Currently the scan is paid for out of pocket.

What the scan doesn’t do:
  • Offer an explanation for cognitive impairment in those patients who don’t have Alzheimer’s.
  • Identify co-existing vascular disease or other cause of progressive dementia.
  • Identify and modify factors worsening cognition, like medication side-effects or other illnesses.
  • Tell patients how quickly their dementia will progress, and what kind of help they will need in a year. The progression of Alzheimer’s is highly variable from individual to individual.
  • Provide dementia education and support to family caregivers.

In short, whether we’ll benefit from the scan really depends on how much families and clinicians benefit from eliminating that period of uncertainty, as well as on our ability to provide good dementia evaluation, management, and support to patients and families. 

Unfortunately most dementia patients currently get sub-optimal medical care, and their caregivers get inadequate coaching and support.  If the scan helps bring people to the resources they need earlier, and more effectively, I’ll be for it. But if it turns yet another radiologic money suck and everything else continues as usual, I’ll be disappointed.

In a nutshell:

The pragmatic outpatient evaluation of someone with memory complaints involves much more than answering the question of whether or not there is Alzheimer's pathology in the brain. 

However, using the new scan to get an answer to that question sooner rather than later could eliminate a lot of the uncertainty and watchful waiting that families and clinicians currently experience. 

If (and this is a big if) this helps patients and families access better dementia care sooner, the brain scans could be quite beneficial.

[Interested in Alzheimer's diagnosis? Here's a related post: Four things people with possible Alzheimer's really need.]

1 comment:

  1. A thoughtful and practical piece - thanks for writing!


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