Saturday, June 30, 2007

Complementary and alternative veterinary medicine

Creeping into textbooks: one example

There have been rumblings here an there that discussing the many fallacious and uncritical alternative and complementary approaches to medicine is just a continually boring re-hashing of old already debunked claims. That may be so to a certain extent, but so many of these claims keep coming back around, either with some new “legitimizing” outer wrapping or as just the same re-regurgitated inanity and they need to be addressed and not ignored.


Indeed, how else can one deal with the interminable stream of blather that even seems to be creeping into the halls of higher education? The growing consensus within the scientific community to act against this tide of ignorance through cooperative groups such as American Association for the Advancement of Science (AAAS) or the ebm online digest , as well as educational websites such as Seed and Sense About Science among many other resources are exciting out reach programs. Of course, the many wonderful science blogs also serve a useful purpose by providing added perspectives, sometimes unique, that are available to anyone who is interested, and who knows, may even help expand the practice of reason and measured thought.


So it is today, I have been presented with news that a new and informative chapter has been added to the veterinary reference book “Clinical Avian Medicine” and- you guessed it- the title of this all important new addition is “Integrative Therapies.” Not the best thing for a grouchy “allopathic” vet to receive early in the morning! (By the way, I apologize for the alternative medicine rant the past few days, but this week at work it seems as if I am literally tripping over the stuff.)


The information service providing this news was kind enough to e-mail the whole added section of “Integrated Therapies” and it is brimming with an amazing assortment of assumptions, inaccuracies, fallacies, and implausible goodies. In the interests of brevity, I will address only a few of these items for illustration (although occasional future posts will consider this particular chapter again).


This new section to Clinical Avian Medicine is written by an R D Ness DVM, of the Ness Exotic Wellness Center. Certified in Chirpractic and Veterinary Acupuncture his web site states; Dr Robert Ness graduated from the University Of Illinois College Of Veterinary Medicine in 1990 with a strong interest and determination in avian and exotic pet medicine…Dr Ness continued to expand his knowledge and training, but kept thinking that there was more to being an animal healer than just mainstream medicine. As frustrations grew over the limitations of standard conventional care for chronic diseases and common problems encountered in his patients, Dr Ness began exploring the realm of holistic medicine and, as they say, the rest is history.”


It seems many who turn to alternative medicine modalities have similar expressions of frustration, but the reality is we all do. Some practitioners though can more readily shed the constraints of the rigors of science based discipline. It seems there forms a disconnect between expanding ones knowledge regarding the process of disease- its natural history, and the earnest wish to do something- to heal. The danger here is that a practitioner risks crossing a line where reality becomes imaginary; not good for medicine.


Right away, there is an illicit assumption that there is something more beyond “mainstream” medicine.This may be a yearning to reach out for the human component of medicine- but CAM is not the way. Indeed, I have felt the attraction and allure that “another way of knowing” might expand my reach as a healer. Unfortunately, this is a road that leads to anecdote, testimony, and belief; the pillars of a postmodernist version of healing and a house of cards.


According to the website, Dr Ness has authored articles in journals and magazines such as the Journal of Avian Medicine & Surgery and the Journal of Small Exotic Animal Medicine. He has also published in veterinary texts such as Veterinary Clinics of North America, the Exotic Animal Formulary, 3rd ed., and Ferret, Rabbits, & Rodents Clinical Medicine & Surgery, 2nd ed.

Along with all this impressive publication history, the web site has an index that offers a dizzying platter of alternative and complementary modalities- you name it, they do it. The topics include Veterinary Chiropractic, Veterinary Acupuncture, Western Herbal Therapy, Nutraceutical supplements, Bach flower therapy, Aromatherapy, Therapeutic Touch (energy therapy), Homeopathy, and Clinical Nutrition…..enough to see that this practice is indeed deep into the “mystic.”

This background information provides a pretty good picture of what this added chapter in “Clinical Avian Medicine” will discuss and the likely orientation and mindset of the author- and it does not disappoint. It also serves to illustrate how CAM modalities can insidiously creep into unlikely realms such as an apparently well done veterinary medical text.

Right off, there is an editors note stating:According to the American Holistic Veterinary Medicine Association, ..."the word "holistic" means taking in the whole picture of the patient – the environment, the disease pattern, the relationship of pet with owner – and developing a treatment protocol using a wide range of therapies for healing the patient."

Here in a brand new textbook (2007), there appears the familiar attempt to co-opt a part of normal practice in medicine - that of taking in the "whole" picture- and this even before the chapter begins. At the same time, a wedge is cleverly and implicitly made between general “mainstream” and a more complete “holistic” practice. That this “holistic” definition practically defines the essence of evidence based practice and the classic medical study of Semiology (study of signs and symptoms) is not considered.

"This includes integrating conventional protocols with possible complementary and alternative therapies – whatever are the most efficacious, least invasive, least expensive and least harmful paths to cure."

When one describes efficacious….least harmful paths to cure from a relativistic viewpoint as in CAM, it is difficult to ascertain what works and what doesn’t. When you blur the boundaries between “conventional” medicines -another false descriptor of science based medicine, and blend in the quagmire of untested, unproven, and implausible therapies the door opens to anarchy, delusion, and more harmful paths.

"Integrative therapies constitute a very wide range of disciplines from around the world. Many of these therapies can be utilized to treat pet birds, although none was specifically developed for avian species. Because birds have not been domesticated, remaining genetically and evolutionarily close to their wild counterparts, they tend to be very responsive to natural therapies. Certain modalities, such as chiropractic and acupuncture, must be modified for differences in avian anatomy and physiology. Others can easily be extrapolated to pet birds from human or other mammals with only slight adjustments. Some examples include homeopathy, flower essences, nutriceuticals and many herbs. Other therapies, such as diffusion aromatherapy, must be used with caution to avoid toxic reactions. Integrative therapy in birds has existed for centuries in poultry medicine through acupuncture and herbal therapy in China."

This paragraph is a mish mash of contradictions, assumptions, unsupported claims, and allusions to implausible therapies such as homeopathy and aromatherapy. For example, the second sentence claims that integrative therapies can be used in birds, though none have been specifically designed for them. However, the last sentence in this paragraph claims that integrative therapy in birds has existed for centuries??

Chiropractic and acupuncture are vitalistic (qi, energy flows) and unproven modalities in humans. To contemplate extrapolating for instance, the concept of the subluxation- never proven to exist- to the avian species pushes the boundaries of reason. There is no historical evidence that acupuncture, as practiced centuries ago was ever created with animals in mind in China. Nutracueticals are a vastly overrated jumble of compounds that have very little evidence to back medical claims in humans or animals.

This is a simple reaction to just a few paragraphs of the introduction. There follows a discussion of different CAM modalities and their supposed application in birds. The goal here is to relate the fact that these types of publications are making it into more serious texts. More alarming is the fact that critical evaluation and judgment have been suspended and ignored somewhere along the publishing process. Authors, publishers, and others of the scientific and medical community need to urgently consider the incipient encroachment of non- science based and ineffective therapies that pretend to “integrate” into the fold of legitimacy without earning it.

Thursday, June 28, 2007

Adventures in data searching

A simple inquiry becomes a trip to the twilight zone

Today on a skeptical discussion board there was a post noting a recent 2007 study regarding a possible link between dairy products and Parkinson’s disease. In it, researchers found a possible association between men and women who consume dairy products and an increase in Parkinson’s. This particular study relied on a cohort study ; “The American Cancer Society’s (ACS) Cancer Prevention Study 11 Nutrition Cohort,” that originally was designed to search for population links to cancer.

The studies findings piqued my interest as this is the latest of several publications probing different questions with respect to dairy intake and possible health risks. Many of these studies also pooled from the ACS cohort group while others used different cohorts or data sources.

To date, no broad negative conclusions can be unequivocally made about dairy consumption. Several studies evidence a real benefit in relation to calcium deposition in younger individuals and postmenopausal women. However, there is a 2002 study linking dairy elements (dairy sourced Ca++, lactose, protein, and vitamin D) to Parkinson’s again in men, and another cohort study alludes to a possible association to dairy Ca++ or some other dairy component and increased prostrate cancer risk, and yet another contradicts this one. A variety of inquiries have looked into any possible links to breast, renal, ovarian cancer, and found none. Some relationships to obesity prevention have shown promise, but so far haven’t panned out.


At any rate, it turns out the 2007 study really indicates a possible moderate link, especially in men, who are moderate to extreme dairy consumers and ends with the caveat that further studies are needed. So, looking deeper into an apparent dairy/Parkinson’s link actually produces more questions than answers. This is because cohort studies serve a purpose in that they may provide information that indicates some association between a cause and a disease. The problem here is that discerning a cause and effect link can not be differentiated from just some meaningless correlation.

What ever the case may be, here is where a routine data search began to take a strange turn. During a quick scan searching for biomedical articles through Relemed (a Pubmed related search engine) to get a feel for the existing data on dairy consumption, I noted a 2006 study that stood out. In spite of the fairly innocuous title “ Calcium, dairy products, and bone health in children and young adults: a reevaluation of the evidence.”

The conclusions of the study seemed to contradict a plethora of other studies- not terribly alarming in and of itself: CONCLUSION: Scant evidence supports nutrition guidelines focused specifically on increasing milk or other dairy product intake for promoting child and adolescent bone mineralization.”

However, looking deeper into the methodology and results, something just did not look right;A Medline (National Library of Medicine, Bethesda, MD) search was conducted for studies published on the relationship between milk, dairy products, or calcium intake and bone mineralization or fracture risk in children and young adults (1-25 years). This search yielded 58 studies: 22 cross-sectional studies; 13 retrospective studies; 10 longitudinal prospective studies; and 13 randomized, controlled trials. RESULTS: Eleven of the studies did not control for weight, pubertal status, and exercise and were excluded. Ten studies were randomized, controlled trials of supplemental calcium, 9 of which showed modest positive benefits on bone mineralization in children and adolescents. Of the remaining 37 studies of dairy or unsupplemented dietary calcium intake, 27 studies found no relationship between dairy or dietary calcium intake and measures of bone health. In the remaining 9 reports, the effects on bone health are small and 3 were confounded by vitamin D intake from milk fortified with vitamin D.”

For one thing, it appeared there was no consideration for the differing level and weights of evidence based on study type. The study appears in Pediatrics (described as the official journal of the American Academy of Pediatrics) where many unsuspecting practitioners and others might attribute more significance to it than it deserves.

The suspicion that something was not right with the science here led me to look into the studies origin and this is when red flags began to pop up. The studies address describes an organization called the Physicians Committee for Responsible Medicine.

A Google search pulled up a web site describing a typical nonprofit:

Founded in 1985, the Physicians Committee for Responsible Medicine (PCRM) is a nonprofit organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in research”

Interestingly, another web site below the official one caught my eye. This site describes the PCRM group as related to an extreme animal activist group:

The Physicians Committee for Responsible Medicine is a wolf in sheep's clothing. PCRM is a fanatical animal rights group that seeks to remove eggs, milk, meat and seafood from the American diet, and to eliminate the use of animals in scientific research.”

Further inquiry revealed that the The National Council Against Health Fraud (NCAHF) states that “The AMA finds the recommendations of PCRM irresponsible and potentially dangerous to the health and welfare of Americans. The AMA charges that PCRM is "blatantly misleading Americans on a health matter and concealing its true purpose as an animal 'rights' organization.”

So the plot thickens from a seemingly innocent study in Pediatrics Journal to, as one digs deeper, an organization with a vested interest in promoting a dairy health risk agenda. But it gets better!

A perusal of the PCRM advisory board reveals a veritable who’s who of quackery oriented individuals:

"Barnard extols the virtues of strict vegetarian (vegan) diets. He claims that when it comes to life span "It's not genetics or fate that gives people long, healthy lives and cuts other people short; for those who want to take care of themselves, it all comes down to diet."

"As defined by Weil, and by most of the other gurus of alternative medicine, alternative and mainstream medicines are not simply different methods of treating illness. They are basically incompatible views of reality and how the material world works, and they cannot easily be combined into any rational and coherent "integrated" curriculum."

"In Spring 2002, my wife Karen and I began researching the career of my father, Henry J. Heimlich MD, the Cincinnati physician famous for the Heimlich maneuver. To our astonishment, information we compiled from hundreds and eventually thousands of documents revealed an unseen, outrageous career history of medical fraud, a far cry from his public image of medical genius and humanitarian."

Perusing the health section of the PCRM web site, there is an article discussing Parkinson’s disease forwarded by Jeffery Bland PhD and written by David Perlmutter, MD . Dr Bland is perhaps the most notorious peddler of the nutritional supplement support ideology and is deeply involved in psuedoscience. Dr Perlmutters website describes his practice:

Perlmutter and his staff rely upon a variety of complementary health techniques including vitamin therapy, nutritional supplementation, herbal preparations, massage therapy, EDTA chelation therapy, and others to provide a comprehensive, fully integrated treatment plan specifically designed for the needs of the individual.”

How a person can start a simple data search on dairy consumption and health; end up in the bizarre world of extreme animal activists-and then suddenly find themselves knee deep among peddlers of psuedomedical alternative quackery is utterly mind blowing!

I can almost hear Rod Serling some where in my head… Welcome… to the twilight zone (macabre music in background)……..

Wednesday, June 27, 2007

On the ethics of bullshit

Clinical trials, CAM, and roads to nowhere

One recurring theme through many of the medical posts on this blog has been to ponder the “humanness” that necessarily forms part and parcel of all our actions as patients and healers. The fascination regarding this grey fuzzy area has been to probe that point where the “right” balance between the unique idiosyncrasies of humanity and the “cold edge” of scientific medicine co-exist. Perhaps this is, as experience seems to reveal, an ever changing place that finds a slightly different equilibrium in each case passing through the examination room.

Be this as it may, how healing practitioners come to terms with this uncertainty provides the basis for understanding that therapeutic modalities can actually impact healing or pretend to impact healing. This is where a dichotomy appears between the scientific “one medicine” model (medicine based on efficacy and evidence) and the confusing morass that is described as complementary and alternative medicine (CAM).

In general, when you claim to be a healing practitioner, you are implying that you have a more intimate understanding of the processes of disease and have access to knowledge that facilitates an approach to effective treatments. Right off the bat the CAM modalities run into the problem that there are, depending on the topic, huge swaths of this healing model that are not based on reality as I’ve pointed out before.

However, here is a pivotal issue. The fact that many of these CAM modalities are made up versions of human imagination in and of itself is not the problem. The problem is that they bill themselves as actual healing practices and build this illusion with deceptive claims utilizing the tools of science such as clinical trials to shroud themselves with a legitimacy of sorts.

What if these practices turned away from these futile efforts and took a more open and honest tact? How about frankly admitting they rely on non science based beliefs and placebo effects. This approach fits better with the already pseudo-religious spiritual tact CAM modalities commonly take anyway.

Ben Goldacre in The Guardian touches on this idea describing the light hearted view that many CAM practitioners ultimately work using psuedo-science or more aptly “bullshit”. This element, even if mostly oriented towards belief and placebo effects comes with some inherent risk (think about the placebo-nocebo effect). Therefore these practitioners need to formulate an honest, ethical system considering bullshit, its belief based orientation, and any risks involved- especially if used as a medicine in a complementary or alternative fashion referencing science based practices.

He states that: “…there is a real issue that quacks undermine the public understanding of science when they promote their trade with dodgy research claims, or distortions of the very nature of evidence. So bullshit is risky, but these problems could be addressed… I can’t help thinking that if complementary and alternative medicine practitioners insist on their right to use bullshit, then maybe they have a responsibility to recognise the risks of bullshit, and to manage these risks, ethically and considerately, like any other byproduct of any other industry. I am calling, in effect, for a new ethics of bullshit.”

Though this is partly in jest, it serves to illustrate one of the key issues when considering whether much of CAM can fit into an effective “one medicine” model. It also helps bring to light the fact that CAM has tried, with success, to claim the human element of healing as their own.

Would this approach threaten the very foundation of CAMs’ existence? Who knows? At the very least, this tact would be a less confusing position and from here they could go on to represent themselves to the public in a truer light.

Tuesday, June 26, 2007

Models of reality

The quantum without waves? One physicists view

Imagine pondering the universe as it presents itself to us, from the majesty of the observable cosmos down to the apparently impenetrable quantum veil, and being able to come up with a vision that ties it together. Indeed, this describes the quest of innumerable individuals searching for that holy grail of physics- the Theory Of Everything.


An endless flow of human thought has considered this question and slowly the nature of reality has revealed itself to us in tantalizing clues here and there scattered throughout the physical sciences. Of course, whether or not humanity will ever reach this goal remains a question. For that matter, there may be no such descriptor of existence within our mental grasp- only phenomena we can observe that reflects a reality beyond our minds.


The paths of human thought that seem to provide the most promise towards gleaning fairly accurate impressions of this reality are those that probe and observe the nature of things. Even if the instruments used; our eyes, ears, touch, and by extension the finer instruments of scientific invention, are all uniquely human in form or construct, they still represent legitimate tools for reaching out to that reality.


Most scientists are realists in the sense that they understand that their measurements, though crucial in framing reality for our comprehension, do not define it. There is probably more reality beyond the reach of the formulas, references, and models we construct. These constructs are best described as tools useful in our endeavor towards learning about the nature of things. There is a classic Skeptico post that alludes to how we learn. Titled: “How do you prove photgraphy to a blind man?” it is well worth reading as it provides an analogy to how imperfect human observation can actually reveal the secrets of reality.


This is where many become confused and mistake the scientific models of reality for reality. For example, the concept of relating wavelength properties to quantum events serves the purpose of describing certain phenomena such as nonlocality and superposition. However expanding this beyond the Planck realm to our vastly more dense reality by alluding to a cosmic consciousness, goes beyond what is actually observed and into unreal and imagined associations.


Victor Stenger in “The Comprehensible Cosmos” notes: The success of physics testifies to some connection to an underlying objective reality. So what might that reality be?” That is the question that we can not answer yet. However, Stenger posits that it is possible to think about this “imponderable” issue using as a base what we can observe of that reality taking into account the fact that our models and equations are essentially tools- that they are not the reality itself.


On the locality of quantum nonlocality

Based on this foundation of observed phenomena, Stenger notes that many theoretical physicists and mathematicians “hold that abstract mathematics, wave functions, quantum fields, metric tensors, and the very equations that hold them together, exist in a world separate from the physical world- a world of ideal “Platonic” forms.”


For example, Roger Penrose envisions that the “ mathematical world is the set of all ‘true’ statements including those that have nothing to do with the physical world and so is not wholly part of that world.” The physical world is a small part of this larger mathematical universe.


This is a form of metaphysics in that it can not be proven using “logic or data.” In this boundary of theoretical physics where observation begins to give way to conjecture Stenger offers a straightforward “metaphysical” theory different than a “Platonic” world view.


He describes an “atom and the void” viewpoint where all the physical “laws” of reality are a result of the interactions between particles. “In this scheme, fundamental particles (or perhaps strings or m-branes) and the more complex objects that are formed when they stick together constitute the sole reality. The observed behavior of these objects is described in the very familiar way we describe the motion of rocks, balls, planets, and other localized bodies of everyday experience- with some differences needed to account for quantum phenomena.”


He stresses that the described wave nature of matter at the Planck level simply serves a purpose and mentions that Feynman and Dirac (great physicists in their own right) both indicated that the concept of waves never needed to be introduced into physics.


Stenger notes for example that: “Quantum mechanics, in its conventional application, treats the interference pattern as a probability distribution of an ensemble of particles, not as the predictive behavior of a single entity called a ‘wave.’ No etheric medium is doing any waving. The wave function lives in a multidimensional abstract space, not in familiar space-time. So it is hardly a likely candidate for a component of reality unless you take the Platonic view.”


With regards to nonlocality, Stenger points out that, from an “atom and the void” viewpoint it is an illusion. To clarify he notes that, at the quantum level, “no direction of time is evident” and nonlocality is not needed if quantum particles can move in both time directions.


According to Stenger “The direction of time of our experience can be understood as a statistical preference in which many body systems, with their highly random behavior, tend to approach equilibrium. The second law of thermodynamics simply defines the arrow of time… In general time reversibility can be used to eliminate many of the so-called paradoxes of quantum mechanics.


This makes it possible for one particle to be at two places at once while behaving locally. Feynman described positrons as electrons going backward in time and this perfectly fits their properties. However, he preferred to stick to the convention of a single time direction and interpreted these “backward” electrons as antiparticles. Nevertheless, Stenger notes: “The model of localized atoms and the void can be made consistent with all observations to date, including quantum phenomena, with a minimum of assumptions once we allow for time reversibility.”


This more straightforward view of the universe leads Stenger to conclude the following: “The laws of physics are simply human inventions motivated by our desire for a viewpoint-independent picture of the universe…the symmetries that lead to the laws of physics are exactly the same as those that would apply if the universe were completely empty. They are symmetries of the void…something comes from nothing because something is more stable than nothing.”


Ref: Stenger, V. The comprehensible cosmos. Prometheus books. New York.2006

Dietary supplement regulations

Some good news.
The FDA announced that supplement manufacturers will now need to ensure their products contain what they claim and that those ingredients are pure. Though this does not address the very important queston of whether these products really work or not it is a step in the right direction.

Junkfood science has a nice post that dovetails well with yesterdays post here. It adds more dimension to the concerns of many regarding the publics misplaced assumptions and the excessive claims rampant throughout the nutritional supplement industry.

Monday, June 25, 2007

Vitamin and mineral supplementation

Nutritional insurance?

Adverse reactions to vitamins and minerals are not as rare as one might imagine. Between 1983 through 2004 the American Journal of Emergency Medicine has recorded a surprising number of adverse event reports regarding these compounds from poison control centers. A total of 1.3 million reports, 175,268 requiring hospital treatment, and 139 resulting in death occurred as a result of these “benign” supplements. Interestingly, the report jumped 62% after the passage of the Dietary Supplement Health and Education Act of 1993 (DSHEA). This act provided for a legal loophole to appear regarding linking questionable products to unsubstantiated health claims.


This is important because vitamins and minerals are regulated under this act, the same one that regulates the broad realm of substances sold under the aegis of the supplement industry with labels claiming the products in question “support”, “aid”, and “maintain” the general health of the body. That these products are produced without rigorous standards of quality control, not to mention an obligation to prove efficacy, is conveniently left out of the national discussion.


This is in sharp contrast to what is assumed by the public at large who believe these products are safe and effective. Vitamin and mineral supplements are a large part of the total supplement industry representing about one third of the 21.2 billion dollar product sale output (2005).


According to Hurley ((Natural Causes) in 1991 the National Maternal-Infant Health survey interviewed 8,285 mothers of preschool children and found that 54.4 % said they gave their children a daily vitamin and mineral supplement. Between 1999 and 2000 the National Health and Nutritional Examination Surveys conducted a survey among 4,862 Americans and found 35% regularly took a multivitamin.


These findings are consistent with the impression that there seems to be an accepted national consensus that vitamin and mineral supplementation is a valid, scientifically accepted recommendation. Indeed, the general message from supplement advocates, producers, and industry trade organizations has been to strongly support their frequent use, even in healthy populations as “nutritional insurance”. Again, Hurley reports that:


“Jeffery Blumberg, PhD, professor of nutrition at Tufts University in Boston, stated in a recent article that remains on the sites of webMD and fox news: ‘Most people need a multivitamin as ‘insurance’. Everybody needs to eat more healthfully. While you’re trying to get there, take supplements.’ Chris Rosenblum, PhD, a spokesman for the American Diabetic Association and associate dean of Health and Human Services at Georgia State University in Atlanta, was quotes on the Web site of a Blue Cross insurer as saying: ‘ A well-formulated vitamin and mineral pill for seniors is the best bet. It’s an insurance policy.’ A 2004 article on the Web site of the Harvard School of Public Health was headlined ‘Dietary Insurance: A daily multivitamin’ and concluded by calling multivitamins ‘about the least expensive insurance you can buy.’ An article in the Spring 2005 issue of the free newsletter distributed by CVS used the same ‘nutritional insurance’ line, as does an article on the Web site of Centrum, maker of one of the most popular multivitamins on the market.” These observations are a brief illustration of how pervasive the concept of vitamin supplementation has become, at least here in the states.


With this level of public familiarity and comfort for vitamin and mineral supplementation, it is not hard to understand how taking a daily pill just seems to make intuitive sense. However, this supposed “institutional” support for regular vitamin and mineral supplementation is actually a thin veneer of opinion and unsupported advocacy. Though, the masses make an illusory link to some type of official medical recommendation or government guarantee- the fact is there is none.


Again Hurley notes: “… no major medical group or government agency actually recommends the routine use of multivitamins for otherwise healthy children or adults, with only a few particular exceptions.” In 2005, the US Surgeon General Richard H Carmona had one vitamin recommendation: That every woman of child bearing age take a folic acid supplement.” The American Diabetic Association states, in a position paper that: there is little scientific evidence of benefit to the average person from a low dose multivitamin or multivitamin-mineral supplement.” In 2006 the National Institute of Health (NIH) stated that: the state of evidence is insufficient to recommend either for or against the use of multivitamin/multimineral [supplements] by the American Public.”


Benjamin Caballero, MD, PhD, director of the Center for Human Nutrition at John Hopkins University in Baltimore and a member of the Food and Nutrition Board at the National Academy of Sciences notes: Most of the vitamin supplements consumed in the US are unnecessary, but don’t rely on my opinion. Look at the 2005 Dietary Guidelines for Americans. They don’t recommend any vitamin supplement for the healthy population consuming a variety of foods.” These guidelines represent a continuing effort to stay abreast of the latest science based information.


In a “no brainer” so hard for many to accept they state Nutrient needs should be met primarily through consuming foods.” Robert M Russell, director and senior scientist of the Lean Mayor USDA Human Nutrition Research Center on Aging at Tufts University in Boston adds: “Instead of paying attention to their diet and a mixed variety of foods that they should be eating, people think they’re getting everything they need from a multivitamin, which is not the case. If you’re just depending on a multivitamin, you’re missing out on many, many, many benefits that come from eating a variety of foods.”


Even the health oriented consumer seems convinced and assumes that supplementation “just in case” is generally assumed to be the way to go. But they don’t consider the surprising number of adverse events (that may even be higher if properly regulated), the fact that supplementation often contains far more concentrations of vitamins and minerals than found in food , and that as a whole human consumption today of these substances is the highest in the history of humanity itself! (The improved health, longevity, and quality of life observed in the past century is linked to improved science based medicine, hygiene technology, biologicals (antibiotics and vaccines), refrigeration, improved food distribution, among others- not vitamin and mineral supplementation.)


Though many concerns regarding these supplements are ignored by many here in the US, some European countries have signaled a far more prudent approach. In 2004, the Danish Veterinary and Food Administration refused an application from Kellog’s to fortify Corn Flakes, Rice Krispies, Special K, and fifteen other brands.


As Hurley states: “Danish health authorities… concluded, after reviewing the safe upper limits for vitamins and minerals that had previously been established by the European Community Scientific Committee on Food, that the amounts that Kellog’s wanted to add would bring some citizens, particularly children, over the safe limits.”


They went on to add that any deficiencies in a general diet should be addressed by specifically fortifying for that item- not supplementing “just in case.” The Dutch authorities went on to state that advising supplementation for people (in this case referring to cereal supplementation, but valid in general) on poor diets completely misses the point. There is no evidence that supplementation is the solution. The focus needs to be on consuming a better diet. Would that more people take heed!


Ref: Hurley D. Natural Causes. Broadway Books.New York 2006

Saturday, June 23, 2007

Teen brains: the angst of growing up

What doesn’t kill you will make you stronger

Having two teenagers, I have often marveled at how they could be model young adults one moment, then in the next breath suddenly become demons of the underworld- spitting saliva and barking accusations from one end of their mouth to another. These tumultuous years are full of emotional extremes; incredible high and lows that give full merit to its description of real angst. It is not a philosophical or poetic version, but a gut wrenching, heart pounding visceral angst that reaches down into the very essence of who and what you are.


Indeed, that is exactly what happens to all of us during these brief pubescent years. Perhaps learning what is occurring in a teenage brain will help bring more understanding of why our teens might do some of the things they do. For example, where does that yo yo moodiness come from? How about many teens propensity for risk taking? Where does that maddening expression and disdaining look; that “whatever” attitude come from?


In the last decade neuroscience has given us a glimpse into the teenage mind and has revealed an incredible sea storm of dynamic change. In general, during this stage the brain has no where near the rhythm and fluidity the adult brain might have. It seems to run more like the uneven staccato of an untuned Harley motorcycle rather than the smooth balanced humming of a BMW roadster.


The teenage cortex is undergoing huge fluxes as actual anatomic changes rewire areas and bring “online” new emerging functions between cognitive centers. Hormonal fluxes take part in triggering outgoing behaviors and a yearning for new experiences and risk taking. This period of human development has been described as the second flowering of the brain, second only to the dramatic changes of early childhood.


There is a flurry of change that relates to higher conceptual thinking. The body begins to produce a maze of new and transforming neurotransmitters that create inummerable connections within the brain. Myelination begins to rapidly produce higher speed connections between differing regions and centers. The sum effect is that the cortex begins to grow into a richer, more nuanced, and complex region. This period in life is reminiscent of the transformation from caterpillar to butterfly- that mysterious and sublime point where everything changes.


At the end of this period, there is a reduction of the exuberant fluxes within the brain. As a teen becomes a young adult, his or her brain begins to lose many connections as it begins to shape a “leaner and keener” disposition. In general, it becomes more efficient, balanced, and wise.


One of the most tumultuous areas “under construction” during the teen cerebral explosion is the prefrontal cortex. That area involved in forethought, judgment, and consideration. That this area develops late helps one understand a teens behavioral extremes. It takes a teen more effort to do what adults can do with ease. In a simple experiment Beatriz Luna, director of the laboratory of Neurocognitive Development at the University of Pittsburgh, instructed teens and adults to avoid looking at lights that appeared on a computer screen and an MRI scanner recorded their brain activity.


She discovered that though, both teens and adults were equally adept at diverting their gaze, teens relied much more on the prefrontal cortex than adults. In other words, the mature adult prefrontal cortex efficiently delegated this function to other brain regions. Teen brains used up the all important prefrontal cortex just for this simple task; predisposing them to become overwhelmed. Luna remarks: “So if they’re under emotional stress from peer pressure or in a situation that requires them to multi task, their performance is likely to deteriorate.”


Teens also have difficulty in reading different kinds of emotions from others. For example, they might have trouble distinguishing anger and shock. This relates to the fact they are far more sensitive to the influence of the limbic system- the fight or flight region and source of emotional feeling. The adult prefrontal cortex, on the other hand, generally has a tempering effect on these surging feelings.


If that weren't enough, other factors influence the tumultuous impulses within the teen brain. Dopamine surges bring about powerful urges to experiment and take exceptional risks. This is a period of searching out and moving on; flexing ones wings so to speak. There are profound evolutionary pressures at work that likely relate to expanding outward from immediate family bonds, to find new partners, developing independence, and exploring new opportunities.


There is also an added window of susceptibility for teens towards many negative dangers presented to them. There may be an increased predisposition to addiction, and adverse risk taking that pushes the boundaries too far. This is part of a parents own unique form of angst! On the positive side Scott Swartzelder, a neuoropsychologist at Duke University states that: “A brain in flux is more open to new experiences and to exploring the world- all of which enhance survival.”


Overall, this insight brings some sense and reason to why teens can be as maddeningly and abrasively frustrating one moment yet wonderfully gentle and cooperative another. Some of us adults may forget we once had pretty major mental surges, epiphanies, and far reaching urges- that we were once teens as well.


Surviving these years provides the foundation for our brains to develop towards broader awareness. It allows for the “I am me” in us to fully flower and reach the most profound contextual depths of “humanness.”

Friday, June 22, 2007

The art and science of medicine





A response

The following is a slightly expanded response I wrote in a comment thread regarding the "On evidence based medicine and the art of healing" post. It is interesting to dicuss the fallacious and not so fallacious claims (mostly the former). If any one has ideas of communicating how science works in a medical context, please feel free to comment.


''Evidence-based medicine doesn't rely on clinical insight, medical training or personal experience.''


On the contrary, EBM relies intimately on them. EBM is "the conscientious, explicit and judicious use of current best evidence in making decisions about the care of the individual patient. It means integrating individual clinical expertise with the best available external clinical evidence from systematic research." (Sackett D, 1996) The evidence, by itself, does not make a decision for you, but it can help support the patient care process. The full integration of these three components into clinical decisions enhances the opportunity for optimal clinical outcomes and quality of life.

"It is based on data from medical journal articles, epidemiology and economics, which relies on randomized clinical trials, which doesn't even require a medical education.”


Evidence-based medicine "converts the abstract exercise of reading and appraising the literature into the pragmatic process of using the literature to benefit individual patients while simultaneously expanding the clinician's knowledge base." (Bordley DR, 1997) You need that DVM or MD title to put it all together for your patient.


''Nonphysicians trained in social science, science or even public policy analysis, have judgement over medicine. Where doctors defined the "standard of care," now payers and purchasers of medical services redefine the standards for appropriate medical care, encouraging doctors to act in ways to promote their financial interest when they make medical decisions.''

Here you are comparing apples to oranges. First, the general body of science based information is gathered by a broad representation of professionals from the basic sciences (chemistry, biology, biochemistry, physiology…), research physicians, tenured faculty, practicing doctors to name some. It is from this body of evidence and understanding that medicine needs to rely.


On the other hand, I agree that there are big problems with third party intrusions, socio-political interests, big corporate lobbying pressures…that inhibit the medical profession- but this is not EBM. That these special interests twist and deform whatever they touch does not change the essence of EBM, science, and an honest and open pursuit of knowledge.

''When evidence from a clinical trial suggests that one therapy is superior to another, it can be used to change prevailing medical practice. The effects of this information requires that some medical specialties and medical suppliers lose income while others gain income. And sometimes evidence may be preliminary rather than well established so that their long-term effects are not known.''


This is part of the human condition and the knowledge gaining process- a science based perspective at least provides a self critical, self correcting mechanism to seek the best balance through time.

''Predictive "accuracy" is the chief criterion traditionally used to validate all diagnostic laboratory tests currently in use in cancer medicine.''


Not sure what you mean here. The specificity and sensitivity of diagnostic, prognostic, and therapeutic analysis will vary depending on what you are evaluating- this includes the history and discussion with the patient, examination, and so on- the whole picture helps dictate the interpretation and validity of whatever the modality in question is.

''The "establishment" itself (NCI) has stated on its official cancer information website on "state of the art" chemotherapy, it is unclear whether single-agent or combinations of drugs is preferable for first-line treatment. No data support the superiority of any particular regimen.''

You need to look at what type of neoplastic process you are dealing with before you can state anything about treatment approaches such as chemotherapy. A plethora of information is available to assist in validating what therapies to use.


What the NCI says:

“When doctors discuss a person’s prognosis, they carefully consider all factors that could affect that person’s disease and treatment, and then try to predict what might happen. The doctor bases the prognosis on information researchers have collected over many years about hundreds or even thousands of people with cancer. When possible, the doctor uses statistics based on groups of people whose situations are most similar to that of an individual patient.”


''So it would appear that published reports of clinical trials provide provide precious little in the way of guidance.''


What the NCI says:

“A clinical trial is one of the final stages of a long and careful cancer research process. Studies are done with cancer patients to find out whether promising approaches to cancer prevention, diagnosis, and treatment are safe and effective.”


''The use of clinical trials to establish prescribing guidelines for evidence-based medicine is highly criticized because such trials have little relevance for the individual patient in the real world, the individuality and uniqueness of each patient. The sample of participants in a randomized controlled trial is typically drawn from those deemed most likely to benefit from the protocol. It usually excludes the very young or old, the non-compliant, and those with co-existing illness. In clinical trials, many patients are excluded because they could not complete the rather arduous treatment. So randomized comparisons are of healthier treated patients against all the controls, rendering a lot of trials invalid. While the evidence obtained from the clinical trial may apply to the sample of trial participants, it may have little relevance for the individual patient in the real world.''


“The evidence that supports the validity or truthfulness of the information is found primarily in the study methodology. Here is where the investigators address the issue of bias, both conscious and unconscious. Study methodologies such as randomization, blinding and accounting for all patients help insure that the study results are not overly influenced by the investigators or the patients.


Once you have determined that the study methodology is valid, you must examine the results and their applicability to the patient. Clinicians may have additional concerns such as whether the study represented patients similar to his/her patients, whether the study covered the aspect of the problem that is most important to the patient, or whether the study suggested a clear and useful plan of action.

Anything that happens after randomization can affect the chances that a patient in a study has an event. Patients who forget or refuse their treatment should not be eliminated from the study analysis. Excluding noncompliant patients leaves behind those that may be more likely to have a positive outcome, thus compromising the unbiased comparison that we got from the process of randomization. Therefore patients should be analyzed within their assigned groups. This is called "intention to treat" analysis.


Blinding means that the people involved in the study do not know which treatments are given to which patients. This eliminates bias and any preconceived notions as to how the treatments should be working. When it is difficult or unethical to blind patients to a treatment, such as a surgical treatment, then a "blinded" researcher is needed to interpret the results.


Decision making involves choosing an action after weighing the risks and benefits of the alternatives. While all clinical decisions are made under conditions of uncertainty, the degree of uncertainty decreases when the medical literature includes directly relevant, valid evidence. When the published evidence is scant, or less valid, uncertainty increases.


Decision analysis is the application of explicit, quantitative methods to analyzing decisions under conditions of uncertainty. Decision analysis allows clinicians to compare the expected consequences of pursuing different strategies.”


''There is no proof beyond reasonable doubt for any approach to treating advanced cancer today. There is only the bias of clinical investigators as a group and as individuals.''


There is no proof beyond a reasonable doubt that gravity exists or that the sun will rise tomorrow, so?


Some thoughts:

"In 1998, Dr. David Sackett, using an "evidence cart" on rounds, reported that of 71 information searches to answer clinical questions, 37 (52%) confirmed the management decision, but 18 (25%) lead to a new therapy or diagnostic test and 16 (23%) corrected a previous plan.” (Sackett D, 1998)

“Similar results were report by Crowley et al in 2003. The CAR study showed that of 520 clinical questions for which answers were sought in the medical literature, in 53% of these cases the literature confirmed the management decision, but in 47% of these cases the literature changed the medication, diagnostic test, or prognostic information given to the patient. (Crowley S, 2003)”



“According to G. Michaud, "Most primary therapeutic clinical decisions in 3 general medicine services are supported by evidence from randomized controlled trials. This should be reassuring to those who are concerned about the extent to which clinical medicine is based on empirical evidence. This finding has potential for quality assurance, as exemplified by the discovery that a literature search could have potentially improved these decisions in some cases." (Michaud G, 1998)


“The medical literature is immense, but only a small portion of it is immediately useful in answering clinical questions. The literature reports the whole spectrum of the scientific research process -- the long journey from in-vitro studies to double-blind randomized controlled trials. This has been called the "wedge of evidence" or the "pyramid of evidence."


“An understanding of how various levels of evidence are reported and how this literature is organized will help the searcher retrieve the highest levels of evidence for a particular clinical question. High levels of evidence may not exist for all clinical questions because of the nature of medical problems and research and ethical limitations.”
Ref:

Thursday, June 21, 2007

Sex differences and cognition

“we have to stop assuming men and women are basically the same because they’re not, which represents a fundamental change in how neuroscience has been doing business-a major zeitgeist change is afoot.”

Larry Cahill, UC Irvine


Although still in its infancy, neuroscience has recently made fascinating in roads into clear differences in neuro processing between the sexes. Using such instruments as fMRI (functional magnetic resonance imaging) and Pet scans to probe the dynamic real time activity of brain function, scientist have discovered unique anatomical and functional differences of male and female brains.


To be clear, men and women on the whole are more similar than they are different. Also, environmental and social conditions likely influence gender neural development in significant ways. The fact remains though that there are real gender cerebral differences that translate into variations in expressed behaviors and cognitive processing. These gender specific differences that can help shed light on subtle male or female cognitive nuances. For example, men tend to use one hemisphere or the other while processing information while relying on specific neural regions to perform tasks. Women tend to utilize broad areas of both hemispheres and multiple regions of the brain to process and perform tasks.


These findings suggest that men and women process information in different ways. An interesting 2005 Harvard fMRI study looking into working memory found that both sexes reached similar results in a working memory test, but used very different neural pathways to get there: “ in a study of working memory-that short-term memory we use to carry on conversations or remembering telephone numbers-a group of volunteers were given verbal attention tasks…while male and female participants performed about the same in terms of accuracy and reaction time, the neural pathways that were activated were different.”


Men and women score similarly in IQ tests even though men’s brains are (factoring in larger proportional size) on average about 100gms heavier than women’s brains. Larger brain size has been correlated with increased intelligence, yet there is no difference in overall cognitive capacity between the sexes.


Studying the make up of each brain reveals a difference in functional emphasis between the sexes. Women have more grey matter and nerve cells more tightly packed together, have a larger superior temporal cortex, and a cerebral blood flow 15 % higher than men, and the prefrontal cortex and temporal cortex are denser. These characteristics suggest that female brains may function more efficiently (making up for their smaller size) and excel in language processing, comprehension, and memory.


Males, on the other hand, have far more white matter-long neuronal fibers coated with a fatty myelin sheath- that enables more efficient communication between distant areas of the brain. In addition, the white matter contains inhibitory neurons that minimize the spread of information throughout the cortex thereby enhancing local processing. This seems to translate into men having an exquisite ability to focus and ignore distractions, as well as being capable of displaying superior spatial reasoning.


These differences likely stem from the ancient conditions of early human social development where men and women filled unique cooperative roles. Perhaps a division of labor brought about by critical survival needs of the species sculpted the neural variations observed in the sexes. Gender differences in cognition may, in part be an inherited evolutionary quality of Homo sapiens.


Another interesting functional difference reflects itself in how the sexes respond to stressful or provocative stimuli. Men utilize the amygdala’s right hemisphere, which is in tune to outside environmental events and communicates with regions that control sight. Women activate the left hemisphere which focuses on the body’s internal environment and is connected to the insular cortex, where sensory information is translated into emotional experiences, as well as the hypothalamus- the command and control for a myriad of physiological activities. Expanding on this Linda Marsa (She Thinks/He Thinks) adds: “the brains right hemisphere distills the essence of a situation, the central idea, while the left side mulls the finer points and tracks the details.”


These findings are just the tip of the iceberg as neuroscience begins to delve deeper into the human mind. It is important to note that these functional differences are general trends in a continuum of functionality between the sexes. As gender roles change and blend into novel situations, our cerebral plasticity in response, will likely adapt and mold these older neural networks in new ways. All the same, these intriguing gender differences help shed light on how and why men and women, though peers, might think a thought in different ways. It illustrates the fact that intelligence and consciousness come in various forms. It also implies that evolution is not done with us!


Ref: Marsa L.She thinks/ He thinks. The brain( Discover) 30-34.Spring 2007