Blessed by the Potato

So I was out at a conference in Victoria, and while I’ve been to a lot of conferences before, it was the first physician-oriented scientific conference I’ve been to. I must say that the quality of the presentations is vastly different than that seen at a typical conference for scientists. The clinicians were much more confident, articulate speakers, like smooth salesmen, which stands in stark contrast to the introverted scientist reading his slides. Unfortunately, they also tended to present fairly shaky data as facts and guidance for future treatments.

For example, there were some presentations on the use of botox and acupuncture to treat chronic pain. The presentations were basically “this worked for these patients, everyone should try it.” Now, here’s the thing about research in medicine: you really need double-blind placebo-controlled studies before you can really say anything with a great deal of confidence, before you really have proof of a treatment working. When this was pointed out to one of the presenters, he countered by saying “Well, the proof is that these people keep coming back and paying for more treatments; these aren’t covered by provincial medicare. If it wasn’t working, they wouldn’t keep coming back.” A bit later in response to another question, another of these practitioners said that about 30% of the people he tried his alternative treatments on returned for more.

The thing is, there’s what’s known as the placebo effect: even if you give someone something that shouldn’t do anything to or for them, some portion of people will find some measure of effect from that treatment. The size of the placebo effect varies greatly depending on how the placebo is presented and what the placebo is acting on. The placebo effect is hard to understand, but we believe that it’s largely “mind over matter” and as such, it seems to work best on ailments that are largely in your head to begin with. If you’re sad, and a respectable looking fellow in a white lab coat hands you a pill and promises that it will make you feel less sad, you’re likely to feel less sad even if that pill is just gelatin-encased starch. Likewise with pain: from a number of studies, it seems that about 30% of people find that their pain gets about 30% better when damned near anything is tried. Pain is a complex phenomenon, but it is at least partly sensation and partly emotional, so it’s something that is easy prey for the placebo effect. Contrarily, something much more objective like a broken bone or open wound is less susceptible to the placebo effect.

So I found it rather disingenuous that when a self-selected sample of people (those who come in to a doctor’s office ready to pay for acupuncture must already believe it may work) has some measure of pain relief, that a doctor can extrapolate from that to suggest that acupuncture is a generally effective therapy for pain.

The double-blind part means that the subjects in a study must not know whether they have the real or placebo treatment: if they knew, it would really eliminate the point of the placebo. That’s blinding. Double-blinding is when the experimenter also does not know, since unconscious clues might be passed to the subjects. All important stuff in research, but let me get back to the placebo effect.

What’s interesting is that placebos are almost as effective as some FDA-approved treatments, and often with less severe side effects (though perhaps somewhat unsurprisingly, placebos also have side-effects; mind over matter cuts both ways). However, it’s generally considered unethical for a doctor to prescribe a placebo because it involves deceiving the patient.

Along with the placebo effect is the tendency for patients to lie and pretend they’re all better when a treatment is noxious. Take, for example, trepanation. Whether or not your chronic pain was cured by the medicine man drilling a hole in your head, you sure as hell were going to shut up about it or else he’d go and drill another one. I haven’t seen it reported, but I also have to wonder if there might be an under-reporting of effectiveness for some addictive treatments: could patients over-report their pain if they’re hooked on morphine, saying it isn’t working when it is in order to get an extra dose?

There was a good article about the placebo effect in Wired recently, even touching on the subtle aspects of pill design that can enhance the placebo effect.

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Consider this: you go to the washroom, you undo your belt, then your button, and your fly, pull your pants down, do your business, then back up in reverse order. You go to the sink and wash your hands (if you work in a hospital or your hands are grody, this may be the second time washing your hands in that visit to the washroom).

You get home, free yourself from the oppressive prison that are your pants, throw them in the laundry basket, and proceed to rock guitar hero in your undies, risky business style. As the laundry basket fills up, and later overflows towards the end of the week, you eventually get around to washing your clothes, and your pants are clean.

But when does your belt get washed?

In a recent comment, Rez asked what I thought about Cold-FX. To be honest, I haven’t read much of the background about it: there are placebo-controlled studies out there, but I’ve only read their abstracts (if that).

For those who haven’t heard, Cold-FX is a product that used to claim it could prevent colds/flus, and reduce the duration and severity if you did catch one. At first I have to admit I thought it was the highest form of quackery, as they claim that they have a patented process that extracts the “active ingredient” from ginseng to make it more potent at preventing colds. Sounds pretty fishy, and their initial sales pitch was via a shouting Don Cherry, which didn’t lend it scientific credibility in my opinion. However I know numerous people who swear by it, and more still who swear by the near-equivalent natural cold prevention of ginseng and echinacea. Health Canada has said they only have proof to advertise reducing the frequency, duration, and severity, so that’s all they claim now (i.e.: they can’t say “immediate relief” anymore). Still, there is some decent evidence that it works in that respect, or else it wouldn’t have Health Canada’s blessing.

Wayfare takes it pretty much every day, and when she does catch a cold it does help somewhat with the symptoms. It can also help delay a cold from coming on full-strength: if she’s at that point where she can feel a cold coming on, she claims she can load up on Cold-FX (what is it, 9 pills a day at that point?) and prevent it from knocking her out completely for a few days. However, even taking the recommended 3 pills a day it doesn’t seem to be able to prevent them completely.

At $1/day for the recommended dosage for prevention I find it a little pricey considering most of the time I wouldn’t be at risk of catching a cold anyway, so I only take it preventatively from late October through December, when flu season is worst at the hospital. That “three times a day every day for the rest of your life” part is where I think it slips over from “useful tool in the fight against colds” to “nice racket if you can get it.” Even during flu season I only take one or two a day instead of the recommended three, which has as much to do with the fact that I think they purposefully set their daily dosage high to sell pills as it does with the fact that I don’t like the coating — the pills seem to stick on the way down, it’s not very pleasant. There’s also the issue of just having too many damned pills to take every day. I’m more convinced of the benefits of loading up on a B-vitamin and D every day, so I’ll take those first, and by then I’m getting sick of throwing pills down my throat when I’m not even sick!

Here’s an interesting question: if there’s some chance that any given cell in your body will turn cancerous per unit time, then if you have more cells, and you live longer, it follows that you have a higher chance of getting cancer. If you extend beyond a human to something big and long-lived, like an elephant or a whale, you wonder: why don’t all whales have cancer?

This is called Peto’s Paradox, and is an interesting one I just heard about.

In fact, cancer is not homogenous across species — humans get it at about 10 times the rate of any wild species. This is partly due to civilization: we don’t die as young from other natural causes, so cancer gets more of a shot to kill us, and of course our penchant for frolicking in toxins (pet dogs and St. Lawrence belugas also get cancer at a higher rate for similar reasons). But even then cancer is not homogeneous: various tissues have different propensities to cancer based in part on genetics, hormones, and environmental exposure (for instance, aside from skin cancers, there aren’t a lot of UV-light caused cancers). So in one sense part of the reason for the paradox is that one of the base assumptions — that any given cell has the same chance to turn cancerous — isn’t quite true.

But the special case of humans (and our domesticated animals) aside, why is it that a wild mouse and a wild whale still have fairly similar rates of cancer? Have whales evolved a resistance to cancer that we should investigate, or could it be related somehow to a fast/slow metabolism (there’s more than one research source that suggests a low-calorie diet for longevity). A recent paper suggests otherwise: that hypertumours (tumours that form inside other tumours) may come into play when you start dealing with larger tumours. After all, a golf-ball sized tumour can kill a person, but would probably go unnoticed in a whale, where it might take something the size of a volkswagen to sink it. In the time it takes that tumour to grow, perhaps a secondary tumour would spring up and feed on the first! It’s an interesting proposal, and the topic of a recent paper.

Complicating this is the interaction between cancer and infectious disease: certain viruses (such as HPV) can increase the likelihood of getting certain cancers. If viruses underlie more cancers than we think, it might explain why the cancer rate is so similar across species of such different sizes.

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Ever since I started working in a hospital I’ve been getting sick like crazy through flu season. It’s not for lack of getting the shot, which I’ve gotten all but one year. The flu shot isn’t usually available to us until mid-November, but for three of those years we got hit early and I got sick around mid-October. One year the shot was admittedly mis-formulated (they have to pick ~3 strains to include in the vaccination, so it’s a guess as to what the problem virus strains will be each year, well in advance of flu season), and nearly everyone got sick. But this year I seem to have finally avoided it: I made it to mid-November without getting sick, got the shot, and I’ve been going crazy with the vitamin B & C pills, plus trying to keep my sleep somewhat normalized (tough given that I had overnight scans in the fall). Now flu season is almost over, and I think I’ve made it through.

Ok, as I’m writing this I am a little sick, but not with the flu — I have a minor head cold and sore throat, but no fever, no body aches, and no alien organisms growing in my lungs!