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Is the new professionalism and ACP's new ethics really just about following guidelines?

The Charter ( Medical Professionalism in the New Millennium.A Physician's Charter) did not deal with just the important relationship of ...

Wednesday, August 30, 2006

Is interval training better for metabolic syndrome?

Physicians routinely recommend exercise for patients with the metabolic syndrome-typically walking.Exercise is a generally accepted strategy to loose weight and improve lipids and glucose tolerance.

Interval training (IT) has been popular with runners for years. The famous distance runner Emile Zatopek popularized it in the 1950's. IT involves alternating high speed or high intensity exercise periods with rest or low energy output periods, e.g. sprinting for 100 yards followed by jogging or walking for 100 yards.There is a "loading" period and a "recovery period".In the recovery period there is at least partial regeneration of adenosine triphosphate and creatine phosphate and decrease in lactate and hydrogen ions.IT is contrasted with constant loading exercise (CLE) or continuous exercise at more or less the same pace or energy output level. Muscle strength and endurance have been shown to increase with interval training while CLE mainly improves endurance.

Recently, Dr. Anna Tjonna and associates from Norway published the results of a small study that indicated that interval training was better than traditional exercise ( i.e prolonged exercise at a lower energy output aka continuous exercise) in terms of improvement in HDL cholesterol and blood sugar in patients with the metabolic syndrome. The IT group exercised at 90-95% of maximum heart rate for 4 minutes followed by a 3 minute rest. They did 4 sets three times a week. The comparison group exercised at 70% of max heart rate for 40 minutes three times a week.

There is a understandable reluctance to encourage sedentary, overweight middle and older aged patients to exercise at that high a level of exercise because of a perceived greater risk of cardiac events and the likelihood of greater musculo-skeletal injuries.We almost always tell patients to begin with a walking program and go from there. "Going from there" often involves someone jogging for a short distance and then walking and then jogging again, which is basically a mild form of interval training. But it is not clear how much exercise or what level of energy output is required to actually change the metabolic parameters of the metabolic syndrome.In fact, the literature on the effect of running on HDL is a bit murky as well. There is some evidence that a higher level of exercise is required to significantly elevate a low HDL than occurs with the usual middle aged metabolic syndrome patient as they try to
"get healthier" with a walking program.Patients with elevated triglycerides usually enjoy a greater increase in HDL with exercise as a result of the fall in triglyceride levels.

I am not going to send a 55 year old man with a BMI of 31 and metabolic syndrome over to the high school track to do wind sprints but the notion of interval training is getting more attention from exercise physiologists and rehab professionals. Deep water running (running in place with a flotation vest in a swimming pool) has been a technique to keep injured athletes fit while they heal and has been applied to older patients to increase their level of cardiovascular fitness and appears to be a relatively low injury risk type exercise.For example,deep water running seemed safe and effective in increasing fitness levels in older women in this study from Sweden. IT has been shown to be feasible and effective in increasing fitness in patients with chronic obstructive lung disease and has been shown to increase anaerobic capacity as well as aerobic in cardiac rehab patients while continuous type training only increased the later.

The single study quoted above is not going to change physicians' exercise prescriptions but maybe there is something metabolically desirable (perhaps a greater increase in the GLUT4 glucose transporter protein or something like that) about the interval training. If so and further data confirm the study from Norway,deep water running may become a way to "treat metabolic syndrome" by providing a safe way to do intervals. ( Disclosure: I became an avid advocate of aquatic exercising 2 years ago.While I was recovering from a subcortical trabecular fracture of the femur aqua-jogging kept me reasonably fit until I could go back to running and was good mental therapy for me and those around me who had to deal with someone who for the first time in 30 years was not running regularly.)

Monday, August 28, 2006

Houston V.A. physicians examine P4P data and find evidence of gaming and treating the chart

The possibility that health care providers (HCP) might try to game the system and treat the chart when offered or forced to play the P4P game is well recognized and quite consistent with basic human nature.

Researchers from the Houston Veteran's Administration Hospital have published an article indicating that behavior of that type does in fact occur. Dr. Laura S. Peterson and her associates write in the August 15 2006 issue of the Annals of Internal Medicine.

They reviewed 16 articles and in 4 studies they found evidence of unintended effects-adverse selection and gaming or treating the chart to achieve financially rewarded goals. Importantly, for those of us who believe this entire P4P movement is motivated by a desire to save money, they found no evidence that these efforts are cost effective. Of course, lack of evidence does not necessarily mean evidence that they are not cost effective but the third party payers and CMS may at some point pull back if they are continue to be unable to show they there are cost savings to the payers. I hope so.

Sunday, August 27, 2006

heuristics and statistics-we need and use both in medicine

In spite of at least one terrible publication to the contrary-the criticism of which is reviewed here- there can be little doubt that experienced clinicians perform better than do novices. Experience and practice really no matter.During the five to ten years it seems to take for a recent medical graduate to become at least a low level expert basically no time is spent on courses on medical decision making.

Does the experienced clinician talk about or think about likelihood ratios or prior probabilities? Does he explicitly use equations to determine positive predictive values etc? Not the ones I have been associated with. What the experienced docs seem to deal in mainly are heuristics. These are rules of thumb,short cuts, and simple judgments that operate in many of the decisions that physicians make.

Dr. Pat Croskerry published an interesting article in the Canadian Journal anesthesiology ( vol. 52:6 p.r1) in which he discusses decision making. He does this from the viewpoint of anesthesiology but it has broad application to medical decision making in general.

His major point is that physicians make many decisions through the mechanisms of heuristics and while they often are effective there are cognitive impediments that limit their usefulness. We need to be aware of those mental tendencies so that we can compensate for them .One example, about which I have written earlier, is "premature closure"., i.e. making a diagnosis and then shutting out consideration that it could be incorrect even as evidence to the contrary accumulates. He mentions many other cognitive tendencies which he refers to as "cognitive dispositions to respond" (CDRs) rather then the earlier tendency to label them as biases or fallacies.Some have intriguing names such as "playing the odds", "Sutton's Slip" and "ego bias". I have not had time yet to research what those terms refer to but some of them may be the topic of a later posting.

His position is that doctors do not typically think in a formalized, statistical manner using formulas which dispassionately weigh the evidence and we should recognize that fact of life and learn about and make efforts to control the CDRs in order to better harness our use of heuristics.

Statistical analysis is an essential element in clinical research but many of the decisions we make in the heat of the clinical battles that take place every day rely on mental processes that seem to have little to do with statistics.

Tuesday, August 22, 2006

The gabapentin story: "Medical education drives this market"

The quote "Medical education drives this market" is attributed to an author of a Parke -Davis business plan found in a legal exhibit in the proceedings of the United States vs Pfizer, and Parke-Davis. Public documents in this case were reviewed and analyzed by Dr. Michael A. Steinman and his colleagues at the San Francisco Veterans Affairs Medical Center in San Francisco and published in the August 15, 2006 issue of the Annals of Internal Medicine. Federal legal action had been taken against gabapentin manufacturer for promoting off-label uses of the drug.

After a physician or medical student or house officer reads this article she should never view certain "CME" activities in the same way.

An important part of the influence campaign of Parke-Davis (P-D)to promote off-label use of gabapentin was though "thought leaders". These physicians are influential physicians often identified by the affiliation with major academic centers. These department chairs, directors of academic training programs or divisions received payments ranging from $10,000 to about $150,000 between 1993 and 1997 in the forms of honoraria, research grants and educational grants. These folks were often the likely role models for house officers , fellows and medical students. This aspect of the multifaceted efforts of P-D to promote non-FDA approved use of gabapentin is the most troubling to me because of the role well respected physicians played. At some early point,a person could have been simply naive and was duped but at some point most had to be complicit at some level.

There are other aspects detailed by the authors including the use of "medical education" companies hired by P-D to ghost write articles and organize meetings, and supply various CME products which were basically advertisements for off-label use of gabapentin.

The full text version of the Annals article is not available until 6 months after publication on line but an excellent review of the article and commentary about both the article and the accompanying editorial can be found in two posts from August 18,2006 on Health Care Renewal.
In addition to outlining the various tactics (advisory boards, consultant meetings, speakers bureaus, programs funded through unrestricted educational grants), Dr Poses raises valid questions about the multiple corporate positions held by the Annals editorial writer as well an academic appointment and how difficult it would seem to be to fulfill the apparently conflicting fiduciary duties that those various roles demand.

The Annals article and Dr. Poses's posts should be part of medical students courses on evidence based medicine. They need to recognize the borders between research,education and promotion which the authors described as "porous". We can hope they will guard these borders better than some-perhaps too many-of their mentors have done. I am grateful to Dr. Steinman and his associates for their work in plowing through some 8000 pages of publicly available documents to give us a "game plan" for selling a drug to physicians. Hopefully this will be as helpful to physicians as giving the offensive play book to the defensive coordinator of a rival football team.

Thursday, August 17, 2006

Yet another analysis of the ALLHAT trial

The idealized world of the medical student as he learns about randomized clinical trials (RCT) is one in which something like this is visualized. Let's do a RCT to find out which is the best way to treat hypertension and then we will have evidence based medicine directing our rational,quality filled medical care.. Well, the ALLHAT trial could be thought of as just such a undertaking so now we should know,right?

With trials of this scope and complexity a large amount of data is generated and rather than a simple black and white answer emerging there are often multiple conclusions all of which do not agree. Such is how this been with ALLHAT. The most recent analysis of this controversial BP trial is from Dr. Frans Leenen from the Ottawa heart Institute.

Here are some of his findings:

Calcium channel blockers(CCBs) were not associated with more coronary artery disease events but were blamed for more episodes of heart failure. Ace inhibitors (ACEi), on the other hand appeared to be more likely to cause stroke,gi bleeding, peripheral artery disease and angina and ( here is a surprise) angio-edema.

Rather than the simple "well that settles it" that was hoped for in ALLHAT, we have arguments and counter-arguments presented,editorials supporting the results and the BP recommendations (JNCVI) largely based on ALLHAT and editorials arguing that the trial was poorly designed and bears no resemblance to the way BP is really treated (i.e. did not compare realistic choices for BP meds) .

We have gone back and forth with CCBs as well. Are they harmful? Are they as good as any other BP treatment ( which is suggested by Leenen's article)? Not only do trial results seem to differ , various analyses in regard to the same trial differ.I doubt if the recent analysis by Leenen will settle much of anything.

Monday, August 14, 2006

Osteopenia-A disease? when do you treat it with medications

Osteoporosis is defined as a decrease in bone mass with pathological changes in the microarchitecture of bone and tendency to fragility fractures. The operational definition is based on the bone mineral density (BMD) measurement and statistical definition is used with osteoporosis said to be present if the BMD is less then 2.5 standard deviations (T score) from the average 25 year old woman's value.For those readings between -1 and -2.5, the term osteopenia is used. By definition 16% of 35 year old women would be osteopenic.

40% of 65 year old women are osteopenic. Of those who should be offered medication? Currently the medications typically used are the bisphosphonates which have largely replaced estrogen which not too long ago was very popular as it was believed to not only mitigate the aging effects of estrogen decline butcould preserve heart health and lessen the risk of dementia.I considered this question because of a quite a number of women who I would see in the office had been placed on bisphosphonate medications by their gynecologist or family doctor or internist seemingly only because of a BMD score in the osteopenic range.

The Osteoporosis Foundation (NOF) and the American Association of Clinical Endocrinology (AACE) have different recommendations regarding the use of medications. NOF seems to recommend medications for those patients with osteopenia with no risk factors if the T score is below -2 and for those patients with T scores of less than -1.5 if they have one or more risk factors which include low body weight ( less than 127),history or family history of fragility fractures,smoking, estrogen lack or excessive alcohol use ,use of certain medications including steroids. AACE would recommends medication if the T score is less than 1.5 IF the patient has had fracture(s) or if the T score is less than -2.5.( This is the WHO definition of osteoporosis so-strictly speaking- AACE is recommending treatment for osteoporosis not osteopenia and recommends treatment for osteopenia only if there is a history of fractures.)

The consensus answer to the introductory questions is no, all persons said to be osteopenic on the basis of a bone density measurement do not need to receive medications. The opposite answer would seem to mean we should be treating those 16% of normal 25 year old women on the basis of their BMD score. Clinical judgment is required to sort out those patients with osteopenia and other risk factors and clinical features would might benefit from prescription medications.Of course with preventive medication use, you never really know if anything is prevented on not in the individual case only in the aggregate. It may make good sense to suggest a bisphosphonate in a 70 year old women who has one fragility fracture already and tends to be a bit unsteady even in the face on a mildly osteopenic BMD while a younger women with the same score who exercises regularly may not be as good a "candidate". As with all preventive treatments-if that is not an oxymoron-the decision should be one reached by the patient after discussion with the physician. and not a unilateral quasi-judicial decision.BMD is one of the factors to consider but not necessarily the determinative one.

A recent article in the Annals of Internal Medicine is referenced as a source for the statement that bisphosphonates are not longer recommended for osteopenic patients. This is misleading.The Annals article was a computer simulation with numerous assumptions (AKA- a cost effectiveness study) which concluded that therapy with bisphosphonates was not cost effective.But it was a close call and with decreases in drug prices the outcome would be turned around and drugs do have a way of becoming generic and cheaper with time.So folks should not take them now but wait until they are cheaper?As is generic with cost effectiveness articles the authors decide what costs too much not the person using the medications ( i.e. the patient).I realize that often the person using the medication is not the person or financial entity paying for the medications, which ,according to my cynical way of thinking,the reason we have cost effectiveness studies in medicine in the first place.In any event, I am not aware that NOF or AACE have made any changes in their recommendations

Friday, August 11, 2006

bacterial pharnygitis-not just beta-strep

Recent entries on DB's Medical Rants have called attention to a somewhat obscure cause of sore throat, namely a potentially very serious infection with a bacteria with the appropriately ominous name of Fusibacterium necrophorum. I will admit I was not aware of that issue.He discusses this infection in the important context of the "long tail" of diagnostic possibilities.

There is another, arguably a bit more common, cause of bacterial sore throat-infection with Arcanobacterium haemolyticum,formerly known as corynbacterium hemolyticum. This form of bacterial throat infection may be associated with a rash so that confusion with scarlet fever caused by beta-strep is possible. A CDC report indicates it may account for as many as 2.5 % of sore throat cases in young patients,occasionally cause a "membrane" on the throat as in diphtheria and may be penicillin resistant.

Clearly group A , beta-hemolytic streptococcal (GABHS) infection is the most common etiologic bacterial pathogen in pharyngitis but Arcanobacterium infection is easily missed. Not only is it similar to GABHS, a typical throat culture might miss A.Hemolyticum because the usual culture plate used for throat swabs may only show a small area of hemolysis after 24 hours with Arcanobacterium and the report would indicate only no beta strep present.

The e-Medicine article on Arcanobacterium infection suggests that the macrolide family of antibiotics are preferable to penicillin which is the traditional drug of choice for GABHS.

Neisseria gonorrhoeae and corynebacterium diphtheria have to mentioned as well although diphtheria is basically of historical interest only at least in the U.S. As time goes on,I'll bet we will add more bacterial pathogens to the recognized inhabitants of the long tail of etiologic agents of sore throat.

Monday, August 07, 2006

Practice,practice, practice-will current house officers have time to do that?

What do some cognitive scientists and the folks who teach you how to take a test (Stanley Kaplan et al) have in common? Answer- a belief in the power of practice and challenges just beyond one's level of competence.

The August 6, 2006 Issue of Scientific American has an interesting article by Phillip S. Ross entitled "The Expert Mind".

It discusses studies that have been done regarding master chess players ( who might be considered the Drosophila of the cognitive scientists) and how they approach and solve chess problems. Novices spend more time analyzing various possible moves than masters who quickly narrow the alternatives down apparently without consciously considering all of them.

Are the masters born or made? The author argues that they are made. The entire article should be read to review the evidence he presents.

"Effortful study" and Practice, Practice, practice with exposure to increasingly difficult problems is the key.What seems important is "challenges just beyond one's competence". To a medical student just beginning the clinical years, just about everything is beyond their competence.

It takes time. He quotes one cognitive scientist who believes it takes about ten years to become an expert.In the "old days" a internist who did specialty training did in fact about ten years total
training although some only took nine years.

Before Stanley Kaplan proved otherwise it was believed that the S.A.T. was an aptitude test. He showed one could be coached to improve one' s S.A.T.score and made a career of that. A key to that improvement was practice ( and of course, knowing what type of problems you would face and therefore be able to practice their solution)

I wonder if the current generation of internal medicine house officers will have enough time in their training to practice enough.With my generation's training (graduation in 1965) we had more time.Counting my two years of pulmonary fellowship, it was ten years from the year I entered medical school.Now someone can complete the IM program ( assuming no fellowship) in as little as 7 years from med school entry. In addition, there is less time per week with the current rules limiting time in the hospital and more material placed into the training requirements that takes away from doctor patient time ( e.g. quality training, cultural competency and my favorite "systems based practice").

One of my former partners in a large internal medicine clinic is convinced the level of clinical expertise in regard to general medicine problems is much greater in those docs who have had specialty training than those "general" internists who have had only 3 years post med school training and not just in their specialty but in general IM matters as well. Maybe the three year trainees need more practice.

Wednesday, August 02, 2006

More on the LABA controversy-a thoughtful analysis from an allergist's perspective

Dr. Stuart Henochowicz, an allergist-internist blogger,recently posted some cogent comments about the use of LABAs in asthma including comments regarding the combo inhalers ( steroids and a LABA).

Asthma patients are often treated by allergists or pulmonary docs or sometimes both and as a pulmonary physician I welcome his thoughts regarding the recent flare up of the concern about the safety of the long acting beta-agonists (LABAs). This exacerbation of concern was triggered mainly by the publication of the poorly done SMART trial and what I believe to be a flawed and overblown meta-analysis in the Annals of Internal Medicine by Salpeter.

Some of his key points are:
LABAs should not be used in asthma without inhaled steroid coverage.
The combo inhalers are very helpful in asthma treatment.
There are data supporting the value of those combination products.

I believe his comments reflect what I sense to be a consensus among physicians who treat asthma on a regular basis, allergists and pulmonary docs. I continue to have concerns that the annals' meta-analysis might cause asthma patients to discontinue their long acting beta agonist-steroid combination inhalers with resultant exacerbation of their asthma.In fact, some medical bloggers have commented that has already happened.

Real medicine's "ill structured problems" versus guideline's well structured ones

I have been thinking lately about the type of medical problems that physicians face. Mathematicians and cognitive scientists talk about well-structured problems and ill-structured problems.

It seems that much of the challenge of patient care falls under the heading of ill-structured problems (ISP). Well structured problems (WSP) are those for which there is a known algorithm.

ISPs have these characteristics:
1.inadequate information form the outset
2.lack of defining guidelines to evaluate the problem
3.mutability of the problem-things changes as you go alone
4.lack of assurance that the problem has been solved

These are complicated problems without a clear cut solution and for which there may not be one right answer. There is no back-of-the-answer to compare with your analysis.

A recent post by Aggravated docsurg gives some great examples of ISPs that a general surgeon faced.Internists have equally demanding cases as well in addition to the simpler, quasi-no brainers.

An ill -structured problem is , by definition, one for which there is no algorithm. Much of the formal education I received in college physics and chemistry and calculus involved the mastery of WSPs of the following type. If a rock drops into a well and the splash is heard 4 seconds later how deep is the well? Physicians do not seem to do much of that type of thinking in their offices.

The folks who paint medicine as mostly a series of WSPs solable by algorithms and auditable for quality and reimbursable of the basis of obedience to those guidelines are either ignorant of or choose to ignore the reality of just how complex and ill structured the issues are that physicians face.

Clinical decisions in these ISPs will require all the knowledge, expertise and judgment the physician can bring to bear factoring in the values and wishes of the patient to try and find the particular "clinical truth" for the circumstances at hand. The quality gurus have no generic algorithm for that process.