Sunday, October 18, 2009

Monday, March 16, 2009

Penny wise, pound foolish

I picked up a Poland Spring water bottle at an event on campus. The label was much narrower than usual. Half of the label was taken up by text crowing about how many trees Poland Spring was saving by shrinking its label. 

Children are dying of cholera in Zimbabwe while we Americans have unlimited access to free water of exceptional quality, and when we purchase water bottled in plastic and driven by truck hundreds of miles we congratulate ourselves on how "green" the label is.


Monday, February 23, 2009

Hard to focus on labwork

1) Yay, new readers! Thanks for the linkage, SBM. I just noticed them, but I look forward to reading the comments.

2) The same naturopath who visited last year came to campus, and his presentation was identical. Details on it later. In short, it was still crappy.

I've just listened again to a podcast episode featuring a Chicago-school economist soul searching over whether he's just as ideological as the Keynesians and how statistical analysis can be twisted to support any bias. I'm not terribly sophisticated in economics, but I recommend the episode if you care about how we know and why we feel certain. The lessons are obviously generalizable to contentious issues in any discipline. Of course, today it made me think about alternative medicine.

I confess, I feel quite confident about certain opinions I have regarding alt med, probably more confident than is strictly appropriate given my scholarship and experience. To be blunt, I basically agree with most of what Steve Novella tells me, and I revel in being part of the skeptical "in-group" of truth seekers. Now, I feel I can justify trusting him because I understand and approve of how he searches for answers, and I really would bet money that I am closer to right than the CAM advocates at school. But of course, they must feel the same way about their opinions and the role models that inspire them! Brian Dunning made this point well recently on Skeptoid. Some humility, or at least empathy, is in order to maintain respectful dialog and keep myself open to the possibility that new information could dramatically change my mind.

Later today I had an experience that drove home these thoughts. Seeing a recent post on SBM about naturopathy, I chimed in with a glib summary of how silly I found today's naturopath. A fellow reader misinterpreted my brief comment and ripped into me for underestimating the absurdity of naturopathy. (On re-reading, he wasn't that harsh. I guess I just saw red when he accused me of being a shruggie. If you're reading, Joe: no hard feelings!) The format of semi-anonyous posting on websites definitely lends itself to sharp lines drawn between groups, and vitriol against "the others" is the clearest proof of membership. I'm not the first person, of course, to note how lack of body language, eye contact, and context make online conversations fraught. But the exchange made me reflect on the dangers of assimilating too fully into any group identity; even a group dedicated to "rationality" could experience herd mentality. If organizing skeptics is ever not like herding cats, then something has gone terribly wrong!

More on the naturopath when I have enough time to write. I'd better get back to my microscope...

Monday, January 19, 2009

Lies, Damned Lies, and CAM Statistics

My latest submission to the campus newspaper: 

Do 4 in 10 of us use CAM?
Sure, if you count vegetarians and Pilates

Flipping through an old [university] magazine in a waiting room, I read [faculty member's] assertion that complimentary and alternative medicine (CAM) should be studied because over 30% of Americans use it. In the Wall Street Journal on 12/26/08, journalist Steve Salerno cited a recent report of 38% CAM usage, although he used the figure in a compelling argument against spending public dollars on non-scientific modalities. Salerno received a response in the 1/09/09 WSJ by a quartet of CAM's finest that used bizarre logic: any lifestyle change (e.g., diet, exercise, stress management) that prevents disease is CAM, lifestyle change is an inexpensive way to prevent chronic disease, therefore we need "serious government funding" of all CAM (including chi manipulation). Physician bloggers from Science Based Medicine call this tactic "the CAM bait-and-switch," and it involves the same conflation responsible for the claim that 4 in 10 Americans use CAM.

Look at the data behind the "4 in 10" claim that Salerno cites. In a 2007 survey (raw data here) of 30,000 households, the most frequently reported use of CAM in the past year was of "nonvitamin, nonmineral, natural products" (17.7% of respondents), and the most common such product was "fish oil or omega 3 or DHA." The next highest rate was for "deep breathing exercises" (12.9%), and number three was meditation (9.6%). In fourth place was "chiropractic or osteopathic manipulation" (8.6%), the vast majority for back, neck, or joint pain. The next five most common responses were similarly unexciting: massage (8.3%, also mostly for back pain), yoga (6.1%), diets (3.6%, primarily vegetarian, Atkins, and South Beach), "progressive relaxation" (2.9%), and "guided imagery" (2.2%). Dude, where's my chi?

Homeopathy made the top ten with 1.8% of respondents. Acupuncture tied with Pilates at 1.4%. Ayurveda, Qi Gong, and Reiki altogether made up less than 1%. 

The big CAM winners were the supplement industry, heavily marketed and poorly regulated thanks to its congressional lobbying, and manipulation/massage for musculoskeletal pain, which is not terribly "alternative." Disciples of CAM can claim a vast public mandate only by appropriating all nutrition, exercise, and relaxation techniques, which are thoroughly uncontroversial aspects of our curriculum. Although Deepak Chopra and Andrew Weil want us to believe that 4 in 10 Americans believe in CAM (incidentally, about the same fraction that denies human evolution), these data suggest a figure more like 4 in 100 for the really magical stuff.

Of course, neither proof of efficacy nor need for research should be a popularity contest. What really matters for any potential therapy are evidence and plausibility, hurdles that cannot be sidestepped by surveys or rhetoric. Each independent CAM modality must stand or fall on its own merits; accepting all CAM because massage feels good and some herbs are efficacious is as intellectually dishonest as rejecting all CAM because Kevin Trudeau is a fraud. 

Proud to say I reached my conclusions on the survey before reading the thorough SBM analysis, though that blog pointed me to the CAM response.  I was primed to be suspicious of such statistics thanks to a great podcast by Mark Crislip on a similar, older survey. 

Sunday, December 14, 2008

This is your Nature on drugs

In college I was once shocked to learn that an engineering classmate routinely took caffeine pills to fuel all-night coding sessions. Some years into medical school, after learning to love coffee, I found myself discouraging a friend from boosting his study efficiency with Adderall. A 12/07/08 commentary in Nature forces me to examine this aversion. Seven authors—experts in fields from law to neuroscience—call for policies supporting “responsible use” of cognitive-enhancing drugs by healthy adults.

Most of us would not deny cognitive-enhancing drugs to Alzheimer’s patients, but the Nature authors assert that such tools should be accessible to all adults, within safety limits. A cognitive-enhancing drug, they argue, is fundamentally no different from cognitive-enhancing activities like sleep, exercise, nutrition, and Kaplan review courses. They stress the need for research programs and policies that promote evidence-based evaluation of the risks and benefits of cognitive enhancements, particularly unknown long-term effects on memory or personality. Current regulations and social norms, however, have set up inconsistent barriers to use of and research on mind-altering substances. Caffeine and nicotine are cheaply available, Ritalin and Modafinil require prescriptions, and forget about cannabis! Although many restricted drugs are indeed too dangerous to be used freely---and like physique-enhancing steroids might rarely be appropriate for children even if rules change for adults---the Nature authors suggest that some resistance is based on puritanical or naturalistic notions that unhelpfully impede progress. Imagine if the first books were burned as "unnatural" memory aids or if Edison's light bulb was extinguished for fear it would raise expectations for human productivity.

We in medicine must address this issue, both personally and professionally. Medical students endure academic challenges that call for every aid possible, and likely many of us rely on cognitive-enhancing drugs to some extent. Sleep-deprived residents face an even starker need, with life-or-death consequences for themselves and patients. Should on-call doctors be given free (or compulsory) alertness drugs? Even if we survive training without pharmacological help, those of us in primary care and psychiatry will undoubtedly face patients eager for such drugs in absence of any disease. Let us have the discussion now so we will be prepared to respond thoughtfully as new drugs are developed and demand increases.

Tuesday, November 25, 2008

Elephant in the Room

An ancient Indian fable tells of blind men disagreeing about the nature of a large object before them, because they fail to realize that they are touching different parts of an elephant. A scientist can be like the blind men in her narrow focus: the physicist sees the world as energy, the chemist talks about atoms, the biologist thinks in molecules, the sociologist focuses on organisms, the ecologist considers systems. Science works because countless investigators in many different fields are all studying different aspects of a single elephant named Nature, and our greatest educators are those who tie the disparate accounts into a cohesive narrative. The analogy works in patient care: the internist, the cardiologist, the surgeon, the anesthesiologist, the nurse, the physical therapist, the pharmacist...each of these players views the same patient through a different lens, focusing on particulars related to his specialty. Unlike the foolish blind men, however, health professionals rest easy with the knowledge that their superficially dissimilar fields are all ultimately based in empirical science. The same models of human physiology and pharmacology support each medical discipline, from nephrology to psychiatry. A big problem I have with "alternative medicine" is that it has no such elephant connecting its diverse claims. 

First of all, lacks a good definition aside from "any ideas about health that are not accepted by most modern physicians." Some advocates use language that smacks of post-modernism or cultural relativism, which has no place in an empirical discipline like medicine. If you think "Western" physicians are "closed-minded" to ancient folk remedies, please take two Aspirin and call me in the morning. Modalities less ancient and foreign are also welcome into the potpourri of, with no prerequisites except failure of acceptance by scientific thinkers. Worshiping ancient philosophies and popular superstitions is no basis for a system of health care. 

Secondly, am I the only one bothered by the fact that ideas conflict not only with accepted theories of reality but also with each other? Reiki, homeopathy, and acupuncture are laughable individually, but I cannot understand how one person can simultaneously advocate all three. Not only would my campus group encourage me to accept an "alternative" pharmacology that defies all chemistry, not only should I believe in "auras" that make a mockery of physics, but I am also asked to accept that ancient Chinese discoveries baffle anatomists to this day. Sorry, you crossed the line by disrespecting our anatomy profs.

The lack of discrimination required to embrace divergent claims reminds me of the title of a book by another type of true believer: The Psychic Sasquatch and their UFO Connection

But surely, the agnostic implores me, no one is really saying that homeopathy cures all disease. Perhaps some diseases are treatable by balancing humors, some by manipulating auras, and others by unblocking chi. That is not what the believers suggest, I respond. The homeopath advocates using his sugar pills for any disease for which no "conventional" treatment exists. I equate such apologia with the scientifically bankrupt idea of Intelligent Design; your treatment of "last resort" is nothing more than a "god of the gaps." If its definition and theory cannot be formulated more precisely, then count me an atheist.

Professional codes of medical ethics clearly state that our actions should be guided by evidence when possible and scientific plausibility at all times. I fail to see how most of meets that standard. Certainly accepting it wholesale, as I seem to be asked to do by campus groups, is ethically and intellectually ruinous.

Forget the Flintstones: Disappointing Data on Vitamin Supplementation

Physicians make decisions based on evidence when possible and on scientific plausibility when necessary. If a relevant randomized controlled trial (RCT) is not available, then a physician must choose whichever action most "makes sense" based on accepted theories and existing evidence. Eventually the lacking data is generated, allowing such choices to be vindicated or refuted with confidence. Recent reports in The Journal of the American Medical Association (JAMA) on vitamin supplementation for prevention of cardiovascular disease (CVD) illustrates this process.

Antioxidants have enjoyed an irrational exuberance in the marketplace, promoted in everything from pomegranate juice to ginger ale. The rationale seems sound: oxidative stress damages biological molecules, so antioxidants might protect against processes of aging, inflammation, neoplasia, neurodegeneration, and more. We know many benefits of a diet rich in antioxidant-containing fruits and vegetables, so similar effects for antioxidant supplementation are plausible. Sadly, many RCTs failed to show a meaningful effect, particularly for CVD (HOPEWHSHPSHATSATBC). The most recent trial was the Physicians' Health Study II, which followed 14000 US male physicians aged 50+ for 10 years. Compared to placebo neither vitamin C nor E reduced the risk of major cardiovascular events, and E actually increased the risk of hemorrhagic stroke. The hypothesis failed badly.

Another longtime scientific suspicion is that B vitamins might prevent CVD by lowering homocysteine levels. A genetic defect in methionine metabolism results in both homocystinuria and early thrombotic disease. Animal models demonstrate plausible mechanisms for homocysteine-mediated vascular damage. Epidemiological data shows a correlation between blood level of homocysteine and risk of heart disease or stroke. The stage was set for conclusive proof, and large RCTs were planned. Trials have been mostly negative, however (VISPHOPENORVITWENBIT), including the recent Women's Antioxidant and Folic Acid Cardiovascular Study, which found no effect for supplemental B6, B12, and folate in 5400 US female health professionals aged 42+, all with a history of CVD or multiple risk factors, followed for 7 years. The vitamin intervention clearly lowered homocysteine levels, but no difference was seen in cardiovascular events. Apparently this correlation did not imply causation.

As JAMA editorials indicate (vitamin Ehomocysteine), many physicians are now concluding that these once-promising hypotheses are incorrect and that vitamin supplementation might actually provide more risk than benefit for some patients. Thankfully, we still have evidence-based tools for preventing CVD; a huge RCT was recently halted early because it found such terrific new results for statins (JUPITER). And for patients willing to make tough lifestyle changes, we can always recommend as smoking cessation, regular exercise, and a colorful diet.