Thursday, February 25, 2010

Evolutionary Medicine

Listening to lectures on sonic foundry can occasionally make me feel like a deranged hermit. I spend days alone at my apartment and venture down to interact with society only for small group discussions, the occasional DES session or a trip to IGA. The atmosphere is distraction free, which I think has made me more efficient and productive this semester (we'll see about that after midterms). The ability to set ones schedule and actually stay awake through lecture has certainly made my med school experience a lot less stressful, but it's not without its frustrations.
Listening to the Immunology lecture just the other day, our Prof. discussed the polymorphism of MHC and the various alleles for each MHC locus within the population. She then asked a simple question: how does this benefit us from an evolutionary perspective. Now, I know Sonic can be misleading but I could hear the crickets. One person ventured a guess but missed the point. Meanwhile, I immediately thought of biodiversity and the lessons I learned from my Evolution class in undergrad - one of those "I'm a biology major, not a pre-med major" classes that I took before deciding to go into medicine. So, I am sitting here screaming duh people, if you don't have a diverse recognition of antigen then a single microbe that goes unrecognized by the entire population can wipe out the whole species! The genetic bottleneck is a big problem in conservation biology. And yes, evolution applies to humans too - even more as we think.

Evolution is often a lost part of medical education. We learn a great deal about the immediate causes of a disease, or even how one can become susceptible, but we are generally not trained in the "why do we get atherosclerosis in the first place?" kind of questions. This piece in Aetiology discusses the med student mentality:

If basic biology and traditional medicine make up the plot of our disease "stories", evolutionary medicine would be somewhat like the moral. My roommate is a medical student and when asked, she can tell you how just about anything in the human body works and what is happening when things go wrong. When asked why things go wrong, her answer will refer to a proximate cause, such as certain foods leading to plaque build up which can lead to heart disease. If the question of why is rephrased, as in why does the disease even exist at all, then she's stumped. This is the question considered by evolutionary medicine. Why aren't our bodies able to repair clogged arteries? Why are we prone to infections? Why are our bodies so good at some things but so inept at others?

The post goes on to discuss the book "Why We Get Sick: The New Science of Evolutionary Medicine". Especially relevant to my fellow immunology students is the following example discussed later in the same post:

So if infections are one evolutionary explanation for disease, what's an example? I recently came across an interesting article about infection and it's relation to premenstrual syndrome. In the article Premenstrual Syndrome: an evolutionary perspective on its causes and treatment, Doyle et al. propose premenstrual syndrome is due to an exacerbation of a set of infectious diseases during cyclic changes of immunosuppression by estrogen and progesterone. While genetics and non-infectious environmental influences have been examined and found largely unable to explain PMS, infectious causes have been overlooked. However, it is know how immune function varies throughout the menstrual cycle in such a way that there could be less effective control of fungi, viruses, and intracellular bacteria, so making the leap to a persistent infection contributing to PMS doesn't seem too difficult. Supporting this hypothesis is a long list of chronic diseases with suspected infectious causes that are exacerbated premenstrually including Crohn's disease with Mycobacterium avium and juvenile onset OCD with Streptococcus pyogenes.

It's a really fascinating interplay between immunology, environment, and genetics. You can also consider the influence of epigenetics for good measure and I'm sure your head will start to spin! The book looks like a good read and hopefully something we'll see in the medical school curriculum of the future. Anyone out there read this book or ones like it?

Tuesday, February 23, 2010

Holy Ganges Gets Help

See my post about the potential health benefits of cleaning up the Ganges over at the Global Pulse Journal Blog - my first as a newly minted editor of AMSA's Global Pulse Journal :)

Note for med students and those with an interest in International Health - we're now taking submissions - check out the guidelines and please share your experiences, research and artwork!

Thursday, February 18, 2010

Blog Rounds II

Look what the Google Reader brought home, a series of articles on everything from pharmaceutical advertising to valentine's day and facebook... let's get started:

TBTAM gives pharma advertising a piece of her mind in an old post worth bringing back for those healthcare reform fanatics out there. Yes, we need to have more infromed patients and make healthcare decisions as a team. No, we do not need big pharma giving patients strategies to convince their doc to get the latest and greatest test from their company. Anyone know if the current bills in congress or any proposals for that matter, do anything about direct to consumer advertising?

Regardless of the commercials, Distractable posits that if PCP's didn't have to deal with medicare and medicaid, they would be able to have good businesses that would attract new grads and make house calls again. If any future public option looks like those programs (mountains of paperwork and restrictive reimbursements) then we're in trouble...and though it's not the direct topic posted, CC wonders how she'll choose a residency program in a rural area if she's not already married. I commented that this plays into that family medicine/rural physician shortage in unexpected ways and even relates back to medical school admissions policies favoring unmarried 22yo's that don't want to work in areas where they have no chance of meeting people.

Complicating healthcare reform further is the fact that a lot of our healthcare bills are from self-inflected wounds such as obesity. While difficult, this is an issue that will likely be solved through a cultural shift rather than left to Washington (though we'll need help) and Jamie Oliver has some ideas...

Speaking of ideas, TechCrunch wonders what the world would be like if those facebook programmers turned their talents onto social causes...a few medical ideas are mentioned, anyone out there know of other apps like those?

OK coffee is finished and I REALLY need to get to school before my sunscreen wears off... enjoy!

Friday, February 12, 2010

What's a Geographer doing in Med School?

This is what:

TEDMED: ESRI on Health and Place

I saw a similar presentation at the ESRI GIS and Health conference back in 2007. Things can get a lot more specific than the County/MSA level shown. After doing health histories last weekend at the AMSA Health Fair it made me better appreciate how this information could help piece together a diagnosis... thoughts? Anyone seen anything like this in practice?

Sunday, February 7, 2010


Neuroscience is like anatomy on steroids with less distinguishing characteristics and more interrelations. This makes it more challenging, but also more rewarding. And they said Term 2 would be easy!

In terms of the actual class at SGU, having quizzes where you must distinguish between the Anterior Commissure and Lamina Terminalis on a 200x200 pixel MRI with big thick lines drawn in MS Paint while at the same time labeling the Hypothalamus is the epitome of a throw-away question. Please, either don't label two things so closely together that the lines themselves cover the actual structures and surrounding features or just upload a higher resolution image - this doesn't help me learn anything.

Presentation complaints aside, I can already see the general direction of the class and the material fascinates me. The whole process of how your body is sensed and controlled through your cerebral hemispheres, as if your brain was a reflection of the body, is simply surreal. Though the myriad of structures can feel overwhelming, for each Netter card I memorize, I get information about structures with functions relating to language (Wernicke's Area, the S/I Colliculi's), sense of self (Precuneus), as well as the reflection of the body along the sensory cortex going down the post-central gyri (same goes for motor in the pre-central gyri). The latter formation is what gives rise to this guy which is a visual representation of the brain space we give to different parts of our body: In our case, Human evolution has strongly favored our hands - those nifty tools of ours - as well as our great communicators (larynx, tongue etc). There is a great run down of this on the NIH website with a nice detailed graphic.

For other animals, evolution obviously favored different body parts and structures based on selective pressures. Below is a representation of the mole rat, which has complete control over it's incisors.

This type of information makes for some fascinating science inspired artwork... would like to see more of it! Link if you know of some...

Wednesday, February 3, 2010

Skin in the Game

In the healthcare reform debate, one strategy potential cost containment strategy rests on the idea that patients should have a greater financial stake in their care. They reason that patients that are financially penalized for unhealthy behaviors will quickly change them and thus bring down costs (or at least pay more for their greater need for care). The idea has some merit, after all a lot of modifiable behaviors, such as smoking and diet, lead to higher health care costs.

A recent study in the NEJM analyzes this by comparing two groups of medicare enrollees: those with copayments that stayed the same and those that had their copayments doubled (to both PCP and Specialty docs). If we buy into the argument above, one expects that the higher monetary cost would provide a disincentive to overuse healthcare services.

Interestingly, the results showed the higher copay plan resulted in fewer outpatient visits but increased overall hospitilizations as well as days in the hospital. Apparently, increasing copayments created a perverse incentive: instead of making a cheap doc visit when they had a preventable or more cheaply treated condition, people waited until it got worse (hoping it would go away, which some issues probably did) and then ended up requiring more expensive care.

Caveats: this was among medicare patients, who are elderly (read:expensive) patients, but the results are compelling. If we are going to incentivize patients to take control over their healthcare costs, this doesn't seem to be the way to do it.

Perhaps as an editorial pun, the NYTimes Health section also ran an article about Henrietta Lacks, the women whose cervical cancer gave rise to the HeLa cells that revolutionized the development of numerous vaccines and medicines. A boon to research...and profits! Oddly, in this case a patient's skin was literally in the game, yet while society benefited the patient (or family) didn't see any kind of reward (the book looks really fascinating!). Another case arose later that went to court in the 80's and found that the patient in question didn't have the right to the billions of dollars made from their cells removed in a surgical procedure. The issue has not gone away though, as noted by NEJM. Perhaps some kind of mechanism to recognize the patients (and at least respect autonomy by asking!) or drive some of the profit back into controlling health care costs is in order?

It simply goes to highlight that our collective, and individual, bodies and paychecks are tied to healthcare in such intimate ways. Of course, I write this as a MS1, I wonder what I'll think of these words in a few years...

Tuesday, February 2, 2010

Blog Rounds

Edit Note: As pointed out by my former roommate and subsequently confirmed on Urban Dictionary, Gunner more appropriately means someone that will do anything to get ahead and purposely sabotage fellow students/workers to get ahead. The definition of gunner below better resembles geeky over-achiever.

Starting a new tradition to get myself to post more often: Blog Rounds. Since I am not allowed anywhere near patients for quite some time, I figured I could do a weekly webside routine with various blogs of the medical world. And yes, it was inspired by Grand Rounds except that theirs is interesting and GRAND. I'm just looking to consolidate the stories I found in Google Reader ;)

So let's begin:

The Blog that Ate Manhattan did a nice job of summarizing the med blogosphere's thoughts on the iPad as well as giving her own opinion. The tablet concept for hardware appears to have obvious uses in medicine, but the details will get worked out in the software realm.

Callous Callostomy meanwhile tackles the 'gunner' attitude head on. At any school there are people that see those that work hard academically and like to poke fun, it's the same at med school (here too). I have two thoughts on this: 1. The number of times someone uses Gunner is in direct proportion to the number of hours they are secretly studying their a** off while pretending not to be/care. 2. C'mon people! We are in med school - the harder you work the better doc you will be and people's lives depend on us knowing stuff, not just knowing enough to pass the boards.

Finally, just in time for my Neuroscience class is a nice post from Dr. Shock on the neuroscience of jazz. I plan on re-reading this once I have finished Neuro as looking at it now I see lots of terms already mentioned in class... that I should be studying!

That's all for this round... time to hit the handouts.

Monday, February 1, 2010

Medblog Mania

Stumbling around the internet, I managed to find the medGadget Medical Weblog awards finalists which listed some really great blogs that you should check out(see the website and my newly updated blogroll). One of my favorite things about blogs is the blogroll and once I found some quality medblogs from that site I started hitting up links and before I knew it I had spent hours reading about the tattoo to tooth ratio and a med student that was diagnosed with cancer (Hodgkin's) 3 weeks before USMLE Step 1. I also learned how essential Physics is to my medical career as well as found an interesting blog that details random and crazy medical inventions from the 1800's.

All this inspired me to get off my butt and update my blogroll, rss feed and other assorted details of this site. I also managed to find a bunch of SGU bloggers (see the blogroll) - none of which are officially sanctioned by the school :P

OK I finished my coffee, time to go to school...enjoy the links and leave a comment if you have some favorite medblogs!