How Diseases Keep You Healthy

The doctor comes into the exam room and looks at you with that stern but sympathetic look; his hands hold your test results and you feel the worst must be coming.

“I’m sorry Mrs. Smith, your test results came back you have Phenylketnonuria, more commonly known as PKU. With proper diet the effects on your neurological system can be controlled. (Then he grins) On a brighter note it protects you from miscarriages so you and the mister don’t have to worry about that family line!”

“I’m sorry Mr. Greenspan, your son Samuel has Tay-Sachs. As lipids begin to build and store in your sons brain and nervous tissue, he will become blind, deaf, and eventually be unable to swallow. (Then he grins) On a brighter note because you and your wife are both carriers of the gene you are both well protected against Tuberculosis!”

“Mr. Humanitarian, I’m sorry to say your breathing problems are due to Cystic Fibrosis, or CF. You will probably experience more repeated lung infections during your life which may lead to severe lung damage. (Then he grins) but your upcoming mission to Africa don’t you worry about those Cholera outbreaks, while you may catch it like other people you CF will protect you from it it killing you! Have a fun trip!”

All of these sound like horrible jokes; yet there is research that shows different allele mutations that occur in populations lead to immune protection against other diseases and conditions. In fact there is a strange effect that occurs that may even explain why some diseases are prone to certain groups or communities and not others. Factors that are related not only to the diseases themselves but the environment that they interact in also.  In a 2008 article by Dr. Pardis Sabeti entitled Natural Selection: Uncovering Mechanisms of Evolutionary Adaptation to Infectious Disease, he shows the relation between sickle-cell anemia and its resistance to Malaria. As those that have sickle-cell escape death from Malaria those without  the condition die off. This causes an increase in sickle-cell in the surviving group, because those without could not fight the Malaria. The population left with only a members that most likely carry sickle-cell now has a disease or condition that can be attributed to their group whereas it might not another where Malaria is not prevalent in the other groups environment weeding out non-sickle cell members.

This can also be shown in why Tay-Sachs is a condition that is normally associated with Jewish populations versus other groups and communities. In Jewish History living in ghetto like conditions was not something that singularly arose during WWII. Those conditions had occurred before, yet if for this post one wants to focus on just WWII the point still can be driven across. Crowded living conditions with bad air is a perfect breeding ground for Tuberculosis (TB). The mutation that causes Tay-Sachs has a built in defense against TB. As those in the ghettos who did not have Tay-Sachs to defend their health against TB outbreaks died, the remaining Jewish survivors were more likely to have Tay-Sachs as a result of its ability to side step the TB. Other communities or groups that did not have both conditions present in their enviroment would not have the build up of Tay-Sachs in their genetic community. This leads to Tay-Sachs associations more with people of Jewish heritage then perhaps other groups.

Some of the reasons for cross-disease protection are a result of the specific way a mutated allele may affect the surface of a blood cell to how it changes the way ones body performs a specific function i.e. an organ or its ability to breakdown specific chemical. Why some of these diseases though are more prevalent in some groups versus others though does bring into the wonders of its protection from other diseases causes an increase of its occurrence in certain populations. Remembering outside factors that contribute to a disease being carried on to future generations while non-carriers die out should be an important thought when focusing on the how and a why one person or group has/gets something while others seem to breeze through unaffected.

Two webpages at this moment discuss in small detail these occurrences, I will find some journal articles that also detail this and tag them on later. To get started though is this interests you:

Dr. Sabeti’s article from Nature Education can be found at:

http://www.nature.com/scitable/topicpage/natural-selection-uncovering-mechanisms-of-evolutionary-adaptation-34539

PBS also has a quick comment page on a few conditions that provide protection from other, it can be found at:

http://www.pbs.org/wgbh/evolution/educators/course/session7/explain_b_pop1.html

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The robot in the white coat

The cover story of the March print edition of The Atlantic is “The Robot Will See You Now”, which explores the various ways that technology is queued to disrupt the medical establishment.  IBM’s Watson is now working through case histories from Memorial Sloan-Kettering, a step toward a much more sophisticated diagnostic and treatment recommendation tool than symptom searches in medical databases.

While I don’t undervalue the talent of an experienced doctor to perceive symptoms that may not be mentioned as complaints and put them together into a better diagnosis, I found myself nodding when one physician on Watson’s training team mentioned the problem of “anchoring bias”, in which one symptom is given priority and others are ignored or seen as unimportant.  That can be multiplied with other prejudices, such as the implicit and explicit bias against fat people that was shown in a study released a few months ago (this post from Jezebel describes the situation well), making it more difficult for members of some populations to receive a valid diagnosis.

The article also discusses the improvements in monitoring technology that are being pioneered by the enthusiasts in the quantified self movement that I’ve posted about previously.  It may soon be possible to wear a monitor that reports regularly and wirelessly to your doctor on an important statistic that is being tracked: blood pressure or heart rate, for example.  A scale or blood sugar tester could share data every time it’s used in the same way.

Potential changes in the career paths of medical workers are considered and decreased contact between doctors and patients for routine issues seems likely.  This could boost the already strong prospects for nurses and physician assistants and — as the article states — allow “everyone to practice at the top of their license.”

This article comes out the same time as a study of robot-assisted hysterectomies determined they are increasing in prevalence despite costing 100-200% more than the standard surgery.  There is little evidence of any improvement in outcome and the suggestion is that the surgery is becoming more widespread due to marketing, not only to the medical establishment but also to patients.  We’ll be wise to remember that new and high-tech doesn’t always mean it’s better for patient care, as Monty Python tried to show us decades ago:

 

Addition: For a half hour audio discussion of this topic, take a listen to Talk of the Nation with Ira Flatow from June 1, 2012.  Flatow speaks with guests Dr. Eric Topol, author of The Creative Destruction of Medicine, Dr. Reed Tuckson, head of UnitedHealth Group, and Dr. Arnold Relman, former editor-in-chief of the New England Journal of Medicine.

A surprising model for health system improvement

In the debate over how to improve health care in the US, systems in other countries are often held up as models.  You know, countries like Rwanda.

Yes, Rwanda.

A thought provoking piece yesterday on The Atlantic made that comparison, citing analysis by Dr. Paul Farmer.  From the article:

Over the last ten years, Rwanda’s health system development has led to the most dramatic improvements of health in history. Rwanda is the only country in sub-Saharan Africa on track to meet most of the Millennium Development Goals. Deaths from HIV, TB, and malaria have each dropped by roughly 80 percent over the last decade and the maternal mortality ratio dropped by 60 percent over the same period. Even as the population has increased by 35 percent since 2000, the number of annual child deaths has fallen by 63 percent. In turn, these advances bolstered Rwanda’s economic growth: GDP per person tripled to $580, and millions lifted themselves from poverty over the last decade.

One explanation for this dramatic improvement is that the genocide in Rwanda allowed for a clean slate upon which a new program could be built.  Farmer and others reject this explanation, however.  A recent report focuses more on interdepartmental coordination and central planning with health as a priority.  The article is a good summary and the BMJ research paper with Farmer as lead researcher has more details.

“Mediator,” France, weight loss, and pharmaceutical politics

“Mediator,” French amphetamine based prescription drug, has been under investigation since at least 2011. Here you can read about  more recent news regarding this “medication.” Trail involving corruption and manslaughter accusation is just starting in France (RMFFM).

Foucault, “Depression and the Limits of Psychiatry”

“What psychiatry presents as the liberation of the mad (from mental illness) is in fact a gigantic moral imprisonment” as Michel Foucault claimedLook here for more on psychiatric practice, DSM-5, and the dangers of the notion “if all you have is a hammer, everything looks like a nail.”

Controversial DSM-5 approved for publication in May

The National Psychologist, January/February 2013 issue page 6, publishes 2 articles: 1) about Psychiatric association approval of DSM-5 publication in spite of complaints from the professional field and 2) how Psychologist organizations react to DSM-5. Both are scanned in one document.

It is worth considering how construction of diagnosis is interrelated with political biomedical authority. The process might not necessarily benefit the individual but it leads to creation of compliant body and collectively a member of Foucalian society.

Rumor and murder of medical workers

In class, we’ve briefly mentioned polio still being endemic in only three countries (Pakistan, Afghanistan, and Nigeria).  In December and January, more than 10 vaccination workers were killed in Pakistan.  Micah pointed out that these workers are often trained individuals from the local community, making the loss far greater than just the polio vaccine,but the loss of a person who was knowledgeable, capable, and willing to be a medical worker.  Now, nine polio vaccination workers have been killed in Nigeria.  From the BBC article:

Some Nigerian Muslim leaders have previously opposed polio vaccinations, claiming they could cause infertility.

On Thursday, a controversial Islamic cleric spoke out against the polio vaccination campaign, telling people that new cases of polio were caused by contaminated medicine.

More information about polio can be found on the World Health Organization’s fact sheet. Great progress has been made — the disease was endemic in 125 countries as recently as 1988 — but it is a hard fight in the remaining three.