A Plague on All Your Houses

 

 

I still remember a seminar I went to years ago in university. It was part of a nebulous course on ‘Health’ that some of us took as a soft route on the way to a bachelor’s degree. It was reputed to consist of essays and a true or false final examination. Also, because the class was small, it was amenable to division into even smaller numbers for several interactive sessions.

There were five of us and a teacher’s aide at the one I remember so well. We were all fresh from high school and, at least in those faraway days, used to being lectured at, rather than actually contributing to the subject matter. The topic that day was Disease, and I remember being mildly interested, but expecting only a list of the usual culprits, complete with causes and treatments -memory fodder for later regurgitation, I suppose.

“What is disease?” the TA started, as soon as we were seated around a rather small wooden table.

One of us -I don’t remember his name now- rolled his eyes and smiled. “Sickness,” he answered, rather smugly.

She smiled in return, as if he’d fallen into her trap rather too easily. “Okay, but haven’t you just used a synonym -defined it in terms of itself?”

He stared at her for a moment, obviously confused. “Well… then, how about saying disease is an abnormality of an organ or a system caused by germs -probably particular germs depending on the disease.”

Her face relaxed and her smile broadened. “Now we’re getting somewhere.” She leaned forward on the table. “Let’s get more specific for a moment. Let’s take tuberculosis… Anybody know the cause for TB?” She glanced around the room, determined to involve us all, apparently.

I looked up at the wrong moment, and she brushed my face with her question and pinned me to my seat with another smile. “Do you know the cause of TB…?” she said, locking eyes with me.

There was no escape. “Uhmm…” I felt embarrassed at being singled out, but the question seemed fairly straightforward. “It’s the tubercle bacterium, isn’t it?”

She sat back in her chair, and shrugged nonchalantly. “Is it?” She said, softly and with just a hint of gentle sarcasm. But her eyes were still sitting on me, and I could tell they meant no harm.

“Tubercle bacillus?” I corrected myself, remembering that people sometimes called it that.

“So…” she glanced around the table again, lifting the weight off my shoulders. “Would you all agree that TB is caused by a bacterium -a bacillus?” she added, looking at me once more. Everybody nodded.

“But don’t some healthy people have a positive skin test for it -the Mantoux test?” she continued.

We all nodded, most of us unwilling to show that we hadn’t known what the test was called.

“So, why is that?” She paused to see if any of us had an explanation, but when nobody said anything, she continued. “If the bacterium Mycobacterium tuberculosis is present…” she slowed down even more for effect. “… if some of us have it… and it causes TB… then why don’t those people have TB?” She straightened in her chair and leaned on the table with her elbows as she searched our faces for the answer.

But she was greeted by blank, albeit confused expressions around the table.

“If disease is caused by the acquisition of a bacterium, then what stops some people from acquiring the disease?”

This was new territory for us, and yet, her eyes stopped at me again. “Our defense mechanisms -the immune system…?” I suppose it wasn’t exactly a scholarly response -even in those days we’d all heard of vaccinations and antibody production.

She started nodding. “Okay, but what makes the immune system strong enough to resist?”

“VSG?” someone said, and immediately blushed because he had obviously taken a leap in the dark with the initials.

She smiled reassuringly. “BCG -Bacille Calmette-Guerin, to give it its full name?” He nodded, presumably relieved. But even in those days, there was some doubt as to its effectiveness, so she merely shrugged again. “But the person may never go for the skin test and so never know she has the bacterium…”

She stared at me again, for some reason. “Well, suppose they’re in good condition -healthy, I mean?” To tell the truth, I didn’t really know what I meant.

“But doesn’t ‘healthy’ mean free of disease? Isn’t that another tautology…?” She walked around the table with her eyes again, but this time more slowly. “So, might there be other causes of disease -apart from the infecting agent, I mean?”

I remember some of us looking at each other, as if we were beginning to understand where she was going with this.

“Where -or maybe under what conditions- do we see a lot of diseases like TB?”

I suppose I remember the seminar so well, because she kept looking at me when nobody else answered. “You mean if somebody’s poor, or living in unfortunate circumstances? Poverty…?” I managed to mumble, hoping that was what she was after.

I still remember her smile.

It was a seminal moment for me, and maybe one of the reasons why I eventually went into Medicine. But it all resurfaced when I happened upon an article in the CMAJ (Canadian Medical Association Journal) from January 22/18 with the rather long and certainly uninviting title, Effect of provincial spending on social services and health care on health outcomes in Canada: an observational longitudinal study: http://www.cmaj.ca/content/190/3/E66

Its thesis, was that spending on health care is escalating so significantly it will soon be unaffordable. The question then, was what to do about it. The study ‘used retrospective data from Canadian provincial expenditure reports, for the period 1981 to 2011, to model the effects of social and health spending (as a ratio, social/health) on potentially avoidable mortality, infant mortality and life expectancy.’ And after using various methods to analyze the figures that I didn’t even try to understand, like ‘linear regressions, accounting for provincial fixed effects and time, and controlling for confounding variables at the provincial level.’ decided that ‘Population-level health outcomes could benefit from a reallocation of government dollars from health to social spending […].’ Or, as they worded it more succinctly in their concluding paragraph: ‘The results of our study suggest that spending on social services can improve health. Social policy changes at the margins, where it is possible to affect population health outcomes by reallocating spending in a way that has no effect on the overall government budget.’

It made me wonder, though, why, if I learned the same thing many years ago, did it still need investigation? Were we so wrong back then? So naïve…?

 

 

 

 

 

 

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A test for Alzheimer’s Disease…

Now here’s a scientific and epidemiologic conundrum: Suppose you develop a test that will give you advance warning of a fatal disease you can neither treat nor prevent. But that foreknowledge might allow an understanding of the really early aspects of the disease -while it was still asymptomatic- that could eventually lead to a treatment. Especially if the disease, as most are, was potentially more treatable in its early stages. What should you do with the test? You need a lot of people to take the test so you can more appropriately generalize the information obtained and yet you can do nothing for them.  And what are the subjects in the test to do with the information? Suppose it is falsely positive and, despite what the results suggest, despite the worry and possible suicides contemplated, they will not actually get the disease. No test is perfect.

In other words, should you screen a particular population with the test, when the value is not so much for the individual tested as for the knowledge that might eventually be useful to someone else? How ethical is it? How cruel is it..?

People have thought about this, fortunately, and some guidelines were offered in 1968 by the World Health Organization for screening criteria. Among them are the suggestions that, not only should the condition be an important problem, but there should also be a treatment for the condition and an ability to diagnose it accurately. They also suggested the condition should have a latent stage when treatment would be expected to be more efficacious.

The problem I have set forth, of course, is exemplified by the recently announced test for Alzheimer’s Disease. (I have included two articles, the Huffington Post summary being the more easily assimilable of the two.)

http://www.medscape.com/viewarticle/821982?src=iphone&ref=email

http://www.huffingtonpost.co.uk/2014/03/10/dementia-early-detection-blood-test_n_4933188.html

It is obvious that Alzheimer’s disease and dementia are both important health concerns in a time when populations are aging in many countries. It would be helpful to know what facilities might be needed so the appropriate infrastructure could be planned for that particular demographic. But equally, it would be useful to know more about who in that population are particularly at risk so they could be studied. A recent report from the Alzheimer’s Association, for example, suggested that women over 60 are two times as likely to develop Alzheimer’s disease over the rest of their lives as breast cancer:

http://www.alz.org/news_and_events_women_in_their_60s.asp

Perhaps of paramount importance is studying the disease at an early stage to search for the cause. To devise a cure. And yet I can’t help thinking about the helpless laboratory animals in our research facilities, poked, prodded and experimentally assigned… But not for their own good. What constitutes a laboratory animal..?

Under what conditions, then, would it be permissible to undertake such a study? Informed consent is mandatory, of course, but what exactly would the participants be consenting to? To knowing about an inexorable decline in cognitive functioning that would rob them of that which they hold the dearest: themselves? We are our pasts -they are what knit the fabric of our identities into a pattern we and others can recognize from one day to the next. The present is a transient gift that constantly slips behind us so we have to pull it along like a shadow as we walk through time. We collect each present and store it on an accessible shelf like books we’ve read. Without them, we become functionally illiterate. Lost. Wandering endlessly through unmarked time as in a dense mist with no signposts we can see, let alone understand.

That this vision may encompass the tundra that is Alzheimer’s is obviously more pessimistic than may obtain: no doubt it is a condition that varies on a spectrum. But the prospects are not appealing, nor the amplitude of changes likely predictable -and I, personally, would not want to know about it until it has captured me and shrouded my awareness of what I had lost.

I suspect this is the reason for the cautionary statements of the investigators and the thrust of the caveats of the WHO parameters. I’m not sure what to do with the test they describe. It is obviously an important step on the road to understanding dementia and yet… I am reminded of that famous “To be, or not to be” speech by Hamlet in which he talks about death, but describes it in terms the more pessimistic among us might suggest could equally apply to Alzheimer’s disease:

The undiscovered country from whose bourn
No traveler returns, puzzles the will
And makes us rather bear those ills we have
Than fly to others that we know not of
I’m sorry, but I don’t think most of us are ready for the test just yet… Or is it only me?