Thursday, July 28, 2005

A new medical blog on the scene

Notes from Dr. RW is the name of a new blog by a hospitalist and the entries so far are well worth reading. I suggest you add his blog to your list of regular reads.I seem to write a lot about hospitalists and it will be good to perhaps get some input from someone in the business as I tend to be a bit skeptical of the movement.

Do inhaled steroids cause osteoporosis? One case control article does not answer the question

A nested case control study published in The January 2005 issue of Chest and commented on in the July/August issue of the ACP Journal Club found no increase in non-vertebral fractures in a group of United Health Care patients. Although a nested case control study has theoretical advantages (limiting selection and recall bias) over a plain vanilla case control, the design of this study seemed destined to provide no new useful information to an important question. I say this because we are given data about low dose, short term use of inhaled corticosteroids (ICS) and only consider non-vertebral fractures. The concern with osteoporosis and fractures is with longer term steroid treatment in patients some of whom already are at higher risk of bone loss (COPD patients).
The commentary by Dr. Frank Thien correctly points out that "the endpoint of a nonvertebral fracture as a risk out come with[the time frame chosen] is unrealistic". "Realistic safety data require longer-term follow-up with accurate estimation of the effective delivered dose". It seems to me this article "answers" a question we really did not need to ask. We do not worry particularly about short term, low dose steroid in regard to osteoporosis less alone fractures.
The editorial in Chest quotes a meta-analysis regarding this issue which found increased risk of fractures and increased frequency of several surrogate markers of bone loss. It should not go unnoticed that the authors of the article failed to mention that systematic review.One could easily come away from the chest article ( not the editorial) with the impression that ICS are not a problem in regard to bones. This is clearly not the case and the editorial makes that clear. Patients on long term ICS for asthma or osteoporosis should be assessed for risk of bone loss, bone density measurements made when appropriate and preventive measures instituted. The complication of a painful spinal compression fracture in COPD patient is very serious and something doctors want to avoid. In this new day of greatly increased skepticism regarding articles sponsored by drug manufacturers, it should be noted that a manufacturer of an ICS product sponsored the Chest article. Two years ago I'll admit that the source of funding was not a fact that I looked for in medical articles but now I've gotten paranoid about it.

Tuesday, July 26, 2005

Another VItamin E lesson-statistics experts do not agree on how to analyze a meta-analysis

There were 11 letters to the editor published in the July 19,2005 issue of the Annals of Internal Medicine critical of the methodology used in the meta-analysis by Miller et al that concluded high dose vitamin E supplements may increase all-cause mortality.
I do not believe a non-statistician could weigh the various arguments and then the counterarguments offered in reply to the critiques.
Here are some to give a sense of this (the letters in the Annals require a subscription)
Dr. Antonio Possolo says in part " instead of the authors' spline (if you Google 'spline' you will harvest a long list of also incomprehensible articles) I employed a nonparametric, locally quadratic, weighted regression to model the relationship between relative risk and the logarithm of dose" He found no statistical significance. Dr. Kent J DeZee et. al criticized Miller's use of the " hierarchical logistic regression rather than traditional meta-analytic approaches, reanalyzed some of Miller's data and found a non significant result. Miller answers point-for-point the criticisms but I challenge a non-statistician to plow through it all with anything close to an understanding.
Here's the thing. We have a meta-analysis ( 19 trials with 135,000 subjects) that found a slight
increase in all cause mortality ( the risk ratio for " high dose" Vitamin E was 1.03 !) In the other corner we have a crowd of epidemiologists and statisticians who put forth arguments that the methodology is inappropriate and the conclusions reached are not justified. Clearly the matter is in dispute because experts cannot agree on how we should analyze the data.
There is very little evidence that the high hopes some had for Vitamin E have been fulfilled. But when we are asked, "Doctor, should I stop my Vitamin E, I have read it may kill me ?", I think we can say the benefits we believed might be forthcoming do not seem to be likely but I do not believe we have good reason for you to worry about having hurt yourself.The researchers cannot agree if there was or was not a very slight increase in risk.
The first Vitamin E lesson is don't get carried away with preventive measures based on observational and case control studies. The second lesson is we have a lot to learn about how to do the analysis part of meta-analysis and at this point the experts don't seem to agree on how to do it except in the simplest, most straight-forward situations.

Monday, July 25, 2005

Prominent academic hospitalist expects growth driven-in part-by desire for "through-put"

Dr. Robert Wachter, Professor of Medicine at UCSF, gave a "state of hospital medicine" address at the annual meeting of the Society of Hospital Medicine (SHM). Wachter listed 3 reasons he believes hospital administrators will continue to promote the hospitalist movement; resident work-load limits, nurse shortage and retention and hospital efficiency (the through-put issue).
The first is only an issue in academic hospitals which is a tiny minority of the country's hospitals, the second is a issue that only time will tell. We do not know if hospitalists will help nurse retention and I am not sure why that would be the case. Working conditions and salary are major issues with all who work and I don't quite see how salaries would change and working conditions are more under the control of hospital administrators than the doctors. If hospital administrators want more nurses they should pay them more money, that makes more sense than hiring hospitalists.
The third reason is probably the driver which is in keeping with the rarely wrong follow-the-money concept. Administrators want hospital beds filled-briefly-with surgical patients. They want Medicare patients with medical illnesses out of the hospital as soon as possible. This what is meant by efficiency. That is where the profits lie. I have talked before about the degree to which salaried hospitalists may be conflicted with that imperative. It will continue to be a empirical question whether hospitalists make more money for the hospitals than they cost. If they make more, the trend will grow. Talk about efficiency seemed louder than talk about quality of care. Thomas Sowell says if you want to see what a organization is all about, do not look to their stated goals or values but rather to their incentives and constraints. I cannot believe that through-put concern of hospital administrators is all about quality.
Another speaker, Dr. Tom Baudendistal used the term "ambulist" in his statement that hospitalists were ideally suited to the role of "championing efficient care". I mention that seemingly self serving statement only to point out the neologism.
Another item which could be a sign of the success of the hospitalist movement is that reports are appearing of burnout.
Kevin, MD has a post linking to a Chicago Tribune article regarding some of the pros and cons of the hospitalist movement and speaks of the economic forces driving the movement.

Thursday, July 21, 2005

It is all about time-not enough time and the best doctors do poorly

DB's Medical Rants recently wrote about his observation of a waning of intellectual interest in house officers which he at least partially attributed to the pressure of too much to do in too little time. I do not know if the waning he observes is entirely due to time pressure but that is a major factor. You can be the best trained, the best informed , the smartest, the most caring physician in the world and if you are seeing 4 new complaints in a hour, you will screw up. It is only a question of how often and how badly. A few years ago I was in the unusual and fortunate situation of seeing patients in the same manner I saw them 20 plus years ago. I had 45 minutes for a new patient and saw a patient who was in the office for the periodic "health consultation" and physical exam. He was 53 years old, previously healthy with the complaint of " losing strength". He noticed it mostly in his arms as he had embarked on a strength building program several months earlier and now could not now do as many reps with as much weight as he could a few weeks earlier. He had seen his insurance company PCP who fielded the complaint, focusing on the hand ( i guess thinking the patient was complaining of hand pain rather than weakness, ordered a hand exam (did no PE ) saw him back in a week and told him he was "probably getting old". There is no doubt he was getting old unless the laws of the universe were abrogated in his case,but on the exam in my office, he had no DTR's in the lower extremities, and decreased sensation in the legs. DTR's were decreased in the arms. I referred him to a neurologist in a anarchronistic clinic where in the neurologist still has one hour for a new patients and quickly the dx of chronic inflammatory demyelinating polyneuropathy was made and treatment begun with impressive clinical improvement. I knew the PCP and knew him to be a well trained , well respected seasoned physician. I believe it was a matter of time.
Physicians have allowed their practice terms of engagement to be dictated by others either directly as in some HMOs or large clinics or indirectly by insurance plans controlling the fees to the point where physicians decide that in order to survive economically they have to increase their output by seeing more patients in less time. Their job satisfaction plummets, patients get short changed if they get any change at all and the error rate accelerated with the risk of malpractice rising with it and patient satisfaction tanks. This may not apply to all physicians and practices but it is closer to the rule than the exception.
I do not know if DB's observation of decreasing curiosity in trainees is all a function of time pressure or not. I have also seen in recently trained IM docs and FPs in a practice setting in which time pressure was not the rule. If it is seen in house officers, who are time and task pressured now, what will happen in private practice when the time crunch is worse because their income may depend on it?

Wednesday, July 20, 2005

Two studies give discordant verdicts on value of Wells' DVT prediction rule

Clinical prediction rules when they work best can give physicians an estimate of the likelihood of the disease at issue. The famous Ottawa ankle rules seem to work very well and have decreased the need for ankle x-ray in many patients.Rules regarding the diagnoses of DVT's have generated many articles and much research and lead to several clinical decisions rules the most widely talked about being the Wells' criteria. The criteria can be placed on a PDA and in the best of times an intern with 2 days clinical experience can with the aid of his thumb arrive at the same answer as the seasoned senior chief of the service. However, in regard to DVT diagnosis how often does the intern find himself in the best of times?. According to one of the two conflicting articles in the latest issue of the Annals of Internal Medicine he may be wrong far too often if he relies on the Well's criteria and a normal d-dimer test. The thinking is that if the Wells rules derived probability is low and the d-dimer is normal, then there is no need to do an ultra sound exam. The whole exercise is basically to avoid doing a u/s exam just as the Ottawa ankle rules exist to decrease the number of "unnecessary" ankle xrays. Two articles in the July 19, 2005 issue of the Annals of Internal Medicine give different assessments of the value of the Wells prediction rules. One, from Holland finds there are too many cases of DVT missed. This study involved a number of primary care doctors in Holland seeing real patients in primary care settings. They found 12% of patients with DVT had a low probability Wells score and 3% had a normal d-dimer. The second article, a meta-analysis concludes that if Wells probability is low and the d-dimer is normal, there is no need to do a u/s. The editorialist, Dr. James Douketis, sides with the pro-Wells rule rule article but importantly says the physician should retain the option of overriding a low Wells score by doing venous ultrasonography. He also says the purpose of the Well score is to complement rather than displace the clinician who will use her clinical judgment to fine tune the estimate of disease. I would add -it is more important not to miss a DVT than it is to avoid "avoid" an ultrasound exam. The Wells score was more important when the gold standard test was venography, a procedure that could ironically cause the problem-phlebitis- you were trying to diagnose. I cannot really understand the imperative to "avoid" a test that is the most definitive we have for DVT and is non-invasive, safe and is widely performed and is very sensitive.The last case of DVT I managed was in a 54 year old previously healthy man who had traveled to New Zealand and had a one week history of a tender, swollen calf. I ordered a u/s which showed a popliteal clot and treatment was begun. What would have been gained by wasting time on a d-dimer test? With the various versions of d-dimer of varying sensitivities you are more likely to be mislead by the d-dimer than with an u/s. Why not go with a test that can demonstrate the clot rather than one that might imply a clot might be present?

Tuesday, July 19, 2005

data collection without theory is not science

Noted epidemiolgist , Dr. Diana B. Petitti, wrote in 1988 (from Kenneth Rothman's book, Causal Inference, p 149-152) that " the literature of epidemiology increasingly is becoming an archive of information derived from mechanical applications of multivariate analysis. ..tabulating every exposure against every disease...investigators are more interested in the mechanics of data analysis than in the substance of the issue being addressed."
It seem even more the case now that in 1988. A non-systematic, non random plunge into a recent ( May 1, 2005) issue of Internal Medicine News found two articles which may illustrate this point. One analyzed incidence cases of type 2 diabetes. Moderate drinkers of alcohol fared best in terms of not becoming diabetic, heavy drinkers and light drinkers had about the same risk. No comment was made re mechanisms. The second article is announced with a headline saying " Bone density screen tied to fewer hip fractures". This is presented as evidence that screening decreases fractures, not that preventive treatment perhaps arising out of the screening prevents fractures.It seem to prevent falls as well ( 16% versus 20%). Participants were screened for 31 variables.
Contrast these with an article from a recent Archive of Internal Medicine from Holland. The researchers postulated that based on the physiology of bladder contraction and the pharmacology of NSAIDs that there might be a relationship between acute urinary retention and NSAID use which is what they found in their data analysis. They studied the issue, formulated an hypothesis and tested it and found supporting data. The study did not falsify their thesis. A Popperian approach was followed in the NSAID article. Petitti says the opposing approach is the "inductivist" approach wherein " knowledge resides in cumulating data, and more data means more knowledge"
She continues " The crucial distinction is the difference between scientific knowledge and factual knowledge. Science is better described as a system of abstract theories than as an agglomeration of factual observations."
John L Casti in his book " Reality Rules" says "...in many ways there is nothing more useful and practical than a good abstraction. This calls to mind Hilbert's dictum that "there is nothing more practical than a good theory' ". I remember cramming for my internal medicine written exam ( back when there was a written and a oral for IM certification.) One of the other pulmonary fellows looked up from a pile of yellow, legal pads on which he had hundreds of notes and announced a epiphany. "Every thing is associated with everything else and whatever finding is described in whatever illness happen 20- 80% of the time".

Monday, July 18, 2005

Evidence Based Medicine can never provide all the answers

Evidence Based Medicine (EBM) 's broad "official" definition is the integration of the best evidence with clinical expertise and patient's values. The popular or limited meaning seems to be EBM is the evidence derived from RCTs and meta-analysis and if all fails observational data or case control studies. It is EBM used in that second sense that I maintain will never, can never provide the answers to all of the questions and decisions that arise in the practice of medicine. There are simply far too many questions and issues that there is time, energy or funds to do all the RCTs to answer all of the questions posed. The Herculean task of gathering all the data necessary to characterize unique patients for Bayesian prior probability determinations is likely one that will never be completed. It is worse that that because as new medications, surgical techniques and diagnostic techniques are devised more and more questions are raised. As new modalities appear, previous RCTs may become no longer relevant. RCTs sometimes are contradictory ( remember ALLHAT, and the Australian BP study and now ASCOT). sometimes a RCT concludes something and as time goes by the data is dissected and analyzed further and the once solid conclusion melts away.Case in point was the DIG trial in which, although no morality benefit was evident , fewer hospitalizations were needed and symptoms relief occured. Later upon more analysis we learn that digitalis may not help women and that the patients whose dig levels were in the acceptable blood levels were harmed.Further, a RCT does not provide all the answers . Consider a RCT that shows a new ACE inhibitor decreases stroke and cv disease risk by X %. There are many questions raised by that. To what degree can we go beyond the data to apply the new treatment to patients whose characteristics would have made them not eligible for the trial. How do we use the drug in patients who may have several or many co-morbidities which -for the most part or the entire part-the study subjects did not have.Further, many of the day-to-day mini-decisions physicians make will never likely fall under the analytic eye of the clinical trial or even the coarse grain data gathering of observational data (aka data dredging).These are such things as when to have the patient return for followup under a myriad of endlessly varied conditions. (A lab test is slightly abnormal, when to repeat it, if at all, or do confirmatory tests, if at all,etc. etc.)
Further as I mentioned before the application of group data or population data to individual patients involves more than knowing the bottom line of the article. It is only the beginning of the decision process for a given patient. You cannot expect the average effect to occur in every given patient you are treating. Even in the circumstance when for a given clinical treatment decision there at least one RCT or meta-analysis that is relevant to the issue a clinician still has to apply the data to the particular case and that often involves much more than" give drug x because a RCT showed that x brings about 30% decrease in mortality".
Why bother saying that RCTs and MAs cannot provide all the answers? Am I just saying the obvious. I believe it is worth mentioning for at least two reasons.
1) the medical students of today may plunge into the real world thinking that all the answers will be revealed through EBM-used in the limited definition given above- much as some of the older generation of doctors may have believed that the truth lay in the wisdom imparted to us by our venerated role models 2) some of the medical and some of the lay literature seem to believe that the answer to all of medicine's real or alleged problems lay in EBM. Some of the answer do lie there, but not all and many will never be addressed.
As is true of all human endeavor many times physicians will fall back on various heuristics for guidance and use human judgment to sort it all out.
EBM will provide the answers if we take the official definition to "really" be EBM because sometimes the integration or application of the "best available" evidence is to apply little or no evidence at all, at least not evidence in the sense of RCT's or even case control studies. Here the individual doctor-not the health care team-has to give individual advice to an individual patient. The physician will be aided with ready computer access to the latest information but as Dr. Thomas Giles-president of the American Society of Hypertension- recently said "we'll need a thinking physician and [a] thinking patient to come up with the best regimen for every individual".

Sunday, July 17, 2005

Medical errors and role of premature closure

Dr. Mark Graber and his colleagues published an interesting article in the July 11, 2000 issue of the Archives of Internal Medicine involving diagnostic medical errors. Diagnostic error was defined for purposes of the study as a diagnosis that was unintentionally delayed,wrong, or missed. Errors were categorized as no fault, system related errors, or cognitive errors. Cognitive errors were either due to faulty knowledge, faulty data gathering or faulty synthesis. Examples of system related errors included 1) biopsy report of cancer not communicated to the patient who missed a clinic appointment 2) consultation request for work up of pulmonary nodule lost 3) radiologists not available to read ER x-rays. The most common cognitive error was faulty information synthesis usually manifest as "premature closure" which is the tendency to stop considering other possible diagnoses after a diagnosis was reached. This is also referred to as a type of anchoring heuristic error.
The authors state that defective knowledge as a cause of error was rare and more commonly reflected problems with synthesis of available information.This refers to a formulation of how humans solve problems namely by searching for an explanation that best fits and then the search stops. Physicians at all levels of training and experience do this.
Are there take-home messages here? With premature closure, the suggestion is to make a conscious effort to not completely stop after you reach a diagnosis but ask " what alternatives should be considered?" This could be done initially and from time to time as the clinical case plays out. Some times things seem so obvious we do not do that but that practice seems like a good mental back up mechanism to minimize errors.
System problems can be varied and the particulars and the particular solutions may vary locally but one problem seemed prominent;radiologists not interpreting films in real time particularly in a emergency setting. Non-radiologist clinicians have been complaining about this since forever.
Personally, I have found this more of a problem in academic settings than in private practice, though it occurs there as well. With digitalization of imaging and broad band internet much of the interpretation could be done at home by the radiologist on call ( and this happens in some settings already). If the clinical doc is awake at 2 in the morning trying to unravel a clinical problem so should the radiologist.
The mechanism(s) of what cognitively occurs with missed diagnoses is not just of academic interest. Dr. Donald A Redelmeier wrote an excellent article entitled " The Cognitive Psychology of Missed Diagnoses" in the Annals of Internal Medicine, Jan 18, 2005. The full text is available by subscription. Cognitive psychology deals with how humans-including physicians-think and he presents basic concepts from that field in the context of a real life clinical case which give them practical significance.
The Graber article dealt with cases collected from 5 academic, tertiary case centers in which there was probably reasonable time to see patients and often with faculty oversight. With physicians in some managed care settings seeing patients every 5-10 minutes, we may well need to develop a revised taxonomy of error generation. Or perhaps most of the errors would be placed in the systems error section under "not enough time spent to figure out the problem."

Thursday, July 14, 2005

Retired doc's suggestion for medical curriculum,Part 12, Beware the language we teach you

Still another mandatory item for the retired doc's medical student's reading list is a 1997 Annals of Internal Medicine article, "The Language of Medical Case Histories" by Dr. William J.Donnelly. The idiosyncratic language of the medical case presentation, particularly, as demonstrated to and executed by physicians in training not only communicates certain facets of a patient's medical problem(s) but it also affects the thoughts and actions of the players who speak those lines.
Dr. Donnelly tells us about medical "Language Maladies". He lists seven, I found number 3 particularly interesting. He speaks of the "agentless passive". An example is " the spleen was palpable" as opposed to I ( Dr. X.) palpated the spleen. This rhetorical device gives the observations of physicians an objective, authoritative status. The case is presented as a view from a " depersonalized nowhere" which obscures the narrator's role and her potential failures in gathering and interpreting the information and obscures the fact that all clinical "knowledge", from the history to the lab tests, to the biopsy and autopsy is less than certain, incomplete, provisional and subject to change. It gives a degree of solidarity to tentative analyses and conclusions.
Number 4 speaks to the loss of standing for a forum for the patient's understanding or lack thereof and the patient's fears and sufferings. ( Note I seem obligated to say patient and not person, another symptom of how our language influences how we think).
Dr. Donnelly explains how verbs are used to establish and maintain a hierarchy of credibility and reliability with patients at the bottom rung, physicians in the middle and laboratory tests at the top. Patients "claim" and ""deny", doctors "observe" and " find" and lab tests "reveal" ( as in the Chest x-ray revealed".)
As Dr. Donnelly says not all of the practices are the "deadliest of sins" but collectively they tend to ignore the "person of the patient" and are at odds with the probabilistic, observer-mediated, provisional nature of all clinical knowledge. He offers some suggestions to mitigate all of this. His first listed suggestion is to introduce the patient as a person, e.g. Mr. Jones and regularly refer to him in that way rather than always as the patient. The entire article is worth reading and thinking about at whatever level of medical training or experience you find yourself.

Prominent cardiologist expresses serious concerns re: use of nesiritide

The July 14, issue of NEJM has an important perspective by Dr. Eic J. Topol, head of cardiology at Cleveland Clinic. Fortunately the Journal has made this free on line and should be read by anyone who has concerns about the FDA's approval record, drug company's promotional activities and the safety and efficacy of a drug that apparently is being widely used. Topol explains that Natrecor was approved by the FDA for acute treatment of decompensated heart failure. He expresses concern, however, that even in this application there are real concerns about its safety and quotes data to support that position. Further concern is expressed that the drug is being promoted for the " maintenance" therapy of chronic HF . This would consist of periodic outpatient infusions, a treatment for which there is no FDA approval nor, according to Dr. Topol, adequate evidence of its safety and efficacy in that context. There are some data from an outpatient trial reference to which can be found at this drug company website. Apparently another trial is underway. More details about the outpatient, non-acute use of nesiritide can be found in a May 17, 2000 NYT article.
With the high profile status of Dr. Topol's article in the NEJM, we are certain to hear much more about this and to the extent that Dr. Topol's characterization of the situation is correct we should. Serious questions are raised.

Wednesday, July 13, 2005

AMA Delegates take strong stand re" P4P, specialty societies cave

At the recent AMA annual meeting, delegates acted contrary to the wishes of their Board of Trustees and said they oppose private-payer or Medicare inititiatives if they do not meet the AMA guidelines for P4P. These include focus on improving performance and not cost control, allows docs to opt out without finanacial penalty and the programs must provide new funds-not just divide the pie differently. The Grassley-Baucus bill that was recommended by MedPac does not meet their standards. In that bill 1%-2% of physician payments would be withheld in a bonus pool to be redirected to the " top performers". Physicians who participate would have to essentially get a EMR system in place to allow performance data collected from their practices.
ACP, AAFP, ACOG and the AAP have all signed a letter to Bill Frist supporting the MedPac proposal . We all saw how "Go along to get along" worked with the gatekeeper Trojan Horse, it will work as badly with the P4P programs. Those who opposed the delegates' position argued that if the delegates ' hard line stance were accepted then physicians would not be in a leadership position. Who really believes physicians will be in a leadership position in any event?

Tuesday, July 12, 2005

NPR's June 9 article on Merck's pressure on Med School re Vioxx

The NPR broadcast on June 9 has a disturbing feature on a drug company's pressure on med schools to reign in criticism on one of the company's products. In this article Dr. James Fries, a professor of Medicine at Stanford, relates the details of a phone call he received from Dr. Louis Sherwood of Merck complaining about a Stanford's researcher's ( Dr. Gurkirpal Singh) comments about Vioxx. Details are found at NPR in the transcript of the reporter's interview with Fries. HCRENEWAL on June 6 described the Fries incident as well as other alleged instances of Merck attempting to silence Vioxx critics at medical schools. Merck and Sherwood deny they were trying to silence critics. As is often the case, news items such as these end up being a " he said-he said" situation but this type of negative publicity is certaintly not what Merck (and others in the Big-Pharma fraternity) need and I doubt current public relations advertising programs will be very convincing to the public that drug companies care about their health. Medical Schools receive significant amounts of funding from drug companies and it would be very easy for the public to believe that whoever pays the orchestra is likely to at least attempt to call the tunes.

Monday, July 11, 2005

Will primary care become a team sport ?Thoughts on The Society of General Internal Medicine's task force on the Future of General Internal Medicine

The Society of General Internal Medicine organized a task force to "redefine the domain of general internal medicine" The final report was released on Sept.20, 2003 and is available in full text on line. In the introductory section the authors state " Chaos may be the word that best characterizes American medicine for many patients and doctors today"
Having said that the stage is set to make suggestions as that implies something has to be done. One of their recommendations was that " general internists should usually work in teams" I found this intriguing as I had never really worked on a team nor do any of my colleagues do so now except perhaps in some metaphorical or virtual sense. One could count the internist and his rounding partner(s) and the receptionist and the nurse and the various folks in the medical field who from time to time play a role as being on a team but that seems a stretch. Because of this emphasis the task force recommends changes in the residency training program to include leadership training to lead these teams.
The task force report does not present a strong case for the team concept. The closest to that I could find in the paper was the following. Although the authors admit that for some types of patients specialists may provide better care than the generalist they quote one paper suggesting that generalists working with specialists appear to" provide better care". While this may be true in some settings it need not be so generally and at most this data point points in the direction of the benefit derived from cooperation not necessarily from formal teams.
No other footnotes are referenced in the context of teams but one citation dealing with the importance of focusing on what patients want did discuss the value of teams.That citation is
Dr. Dana Safran from the Health institute at Tufts-New England Medical Center writing in the Feb. 4 2003 Annals of Internal Medicine. One of the elements Safran believes are essentiall to secure primary care is " adapting of the current functioning of primary care team so that they become visible, meaningful and valued from the patient's perspective."
The only argument for this presented by Safran provides indirect evidence ( ie evidence which if believed requires an inference on the part of the "trier of fact" to accept the matter asserted- to use the words of a law book-). It involves comparison of patient satisfaction in a closed model HMO versus an open model practice. A characteristic of the former is the place of "invisible" teams and emphasis on having the patients seen sooner rather than necessarily having the patient seen by the same physician each time. Patient seem to prefer the open model. They would rather see their doctor than be seen sooner by someone they do not know.
Rather than concluding teams are not well received, Dr. Safran interprets these data to mean that teams need to be made visible and the patients educated to their role and then presumably better care will result. Safran quotes three articles said to provide " considerable empirical evidence" that links the performance of care teams to improved health care and decreased costs. Two of the studies involve intensive care medicine and post op care which seem not relevant to primary care. The third article deal with newborn health care delivery. There is also some data indicating that rapid response teams in hospitals may be worthwhile. However,I see little data available indicating the value of teams in primary care,certainty much less than I would think is needed to state that "visible" primary teams are essential .
I am aware that "teams" is one of the politically medically correct terms to which to pledging allegiance seems required. A body no less august that the Institute of Medicine has placed its imprimatur on it. IOM lists "working as part of interdisciplinary teams" as one of the five core areas which medical professionals should ensure proficiency. In the era of evidence based medicine, I do not know what energizes this team concept movement but it seems to be something other that than sound evidence. No one opposes cooperation and prima donnas are not held in high esteem, but I think a patient in the middle of the night wants to call Dr. Jones not the "health care team".
I worry that with the emphasis on teams, team work , team player etc that we may loose in the shuffle or at least not adequately emphasize a physician prime directive "The individual physician is responsible for the individual patient and the patient's welfare". The incorporation of that concept into a person's makeup is a major part of the transformation of a lay person into a physician.

Friday, July 08, 2005

Randomized trial-treatment of essential thrombocythemia-hyroxyurea better than anagrelide

The July 7, 2005 issue of NEJM reports a RCT in which cases of essential thrombocythemia at risk for thrombosis were treated with either hydroxyurea plus ASA or anagrelide plus ASA. The hydroxyurea arm was better in almost everyway. There were fewer arterial thromboses, fewer serious hemorrhages and fewer withdrawals from therapy in the hydroxyurea group while the anagrelide group had fewer venous thromboses. Essential thrombocythemia manages to pose a risk of both hemorrhage and thrombosis, the former occurring at the higher platelet counts. Concern about the potential leukemogenic effect of alkalating agents lead to the development and clinical application of anagrelide which apparently only affects the platelets, doing little or no harm to the red and white cells. Anagrelide seemed a reasonable replacement from hydroxyurea. However, this RCT strongly suggests otherwise. This was the first head- to- head comparison of the two treatments and although urea was not better in every measured way,
on balance it appears a better choice.

Thursday, July 07, 2005

Harvard professors critical of fellow Harvard prof's article's conclusion re: older physicians

The July 05, 2005. issue of the Annals of Internal Medicine contains several letters critical of an earlier Annals article by Choudhry,Fletcher and Soumerai, the accompanying editorial and even raises questions of "conflicts of interest". The article in question concluded that older physicians may provide lower quality care and need quality improvement interventions.
The journal requires a subscription for full text viewing so here are some of the highlights.
Dr. Martin Samuels of Harvard ( to whom I will always be grateful for his classic "dizzy patient" lecture) and Dr. Allan Ropper question the method of article selection used by Choudhry but more than that he accuses the author of writing a "potentially destructive" article. They go on to say "... age brings 2 things: graciousness and time to realize that fads in treatment and medical reform come and go".
They continue to say "Choudhry and colleagues' review glorifies information, algorithms, and consensus statement and has the unfortunate, probably unintended effect of diminishing experience and judgment. However, its publication is not unexpected. It is part and parcel of an unfortunate course of events in medicine where quantification inadvertently undermines quality while masquerading as evidence. ( ref: clinical experience and quality of health care. Samuels, MA and Ropper, Allan H. Annals of Internal Medicine Vol. 143 number 1 pg 84 5 july 2005.)

Dr. Poses (of HCRENEWAL) and Dr. Joseph Diaz also lists point by point methodological weaknesses of the paper. (ref. same as above pg 84-85)
A similar critique from Poses is available here.
Conflicts of interest have attracted much attention of late, mainly focused on the antics of Big Pharma and their purported manipulation of the medical literature. Dr. Elizabeth W. Loder, also on the Harvard Medical School faculty in her letter( same reference as above,pg 86) raises interesting questions regarding one of the authors -Dr. Robert Fletcher-and his role as co-editor of a section of the product known as UpToDate .Dr. Loder expresses surprise that no potential conflict of interest was reported with the article. Where is the conflict? Loder goes on to say that in interviews following the article's publication, Fletcher, identified computerized databases as a principal solution to the quality problems recognized by the publication in the annals. UpToDate is self described on its web site as a comprehensive evidence-based clinical information source available on the webl and CD-ROM. While the failure to disclose may be no more than an oversight, some may be concerned with the perception of self interest and conflict of interest.
Coincidently, the day I read Dr. Loder's letter, my wife-also a physician-received a promotional letter for UpToDate from Dr. Robert H. Fletcher. The second paragraph says " Old habits of keeping up do not serve us well enough. This is what I found in a recently published study in the Annals of Internal Medicine. The longer the time since graduation from medical school, the less physicians knew about and used new, evidence-based practices." I have not had the opportunity to use UpToDate. It may well live up to the promotional claims. One wonders what is the evidence that use of this product will lead physicians to engage in more " evidence-based practices." (Fletcher's letter does quote a survey of subscribers that found 91 plus % changed "management based on their use" of the product.)
The Annals deserves credit for publishing these and other letters critical of the article and the editorial. However, the headlines generated by the article and the interviews by the press with the authors are not neutralized by the rebuttal and critiques expressed in the letters.
The thoughts of Samuels and Ropper expess a vision of what a good physician should be that looks beyond the simplistic reliance on conformity with guidelines as a measure of quality care and places value on maturity and judgment and experience.

Wednesday, July 06, 2005

Statins may be put in the water supply yet

If we can believe the epidemic of case-control studies, we may yet have to put statins in the drinking water because they seem to do everything. NEJM recently published a case control study that indicated protection from colon cancer with the use of statins. More recently, Dr. Vikas Khurana of the VA Medical Center in Shreveport, La. reported an analysis of a large database that claimed a reduction in the risk of 7 types of cancer by 50% including colon cancer. The records of 1,400,000 veterans from 10 VAs were analyzed.
These were, of course, retrospective case control studies and the author admitted that the duration and dose and type of statin was not factored in the analysis.
I believe the comments I made regarding the NEJM article apply here as well.
It has now been 20 years since NEJM published back to back articles dealing with the incidence of cardiovascular disease in women taking hormone replacement therapy. One paper was from the Framingham group, the other from Harvard reporting from the Nurse's Health Study. One reported a two fold increase in risk, the other a 50% decrease. Had either paper been published alone in such a high profile, widely read and quoted journal the results would have likely been widely acccepted. The editors, however, did the medical community a great service by their article juxaposition choice. Dr. John C. Bailar iii has a excellent chapter in his book " Medical Uses of Statistics" ( NEJM Books, Boston, 1992) in which he discusses Uncertainty about Confounders. Bailar asks the question why did these articles disagree so sharply.His answer was he did not know, an admission he also made in the editorial that followed these two articles. He could not give a specific reason for the difference, but in his book he says that the general reason involves unrecognized and perhaps unrecognizable differences in the study groups. You cannot control for unrecognized confounders in a case control or observational study.The scientific process involves drawing inference from information that is inevitably subject to error. The usual statistical measures of uncertainty ( p values and confidence limits) capture only that part of the uncertainty attributed to random variability in the context of the particular statistical model used.
Every study - even the cream of the crop, the RCT -is subject to those limitations of the statistical method. Of course, the RCTs- unlike the case control studies- control for even unrecognized confounders by the randomization process. So, case control studies and observational studies are much more vulnerable to limitations and the results of those studies need to be viewed with appropriate skepticism and restraint. Analyzing large data bases with outcomes against a battery of potential risk factors or risk modifiers always yeilds a set of statistically significant correlations. The trick is to know what to do with them and what leads to follow. So it may still be premature to add simvastatin to the water supply.

Tuesday, July 05, 2005

How does Vitamin D prevent falls? ( if it does)

Bischoff-Ferrari et al published a meta-analysis in the April 28, 2004 JAMA indicating an approximately 20% decrease in falls in elderly patients treated with vitamin D ( 800 - 1000 u/day).The authors quote several lines of evidence indicating a beneficial muscle strengthening effect of Vitamin D.The effect was evident fairly quickly- noted in 2-3 months in 2 of the 5 studies including in the analysis. A more recent study from a Boston nursing home showed results in the same direction but claimed a 70% reduction in risk of falls.If the only evidence of efficacy were this single study,few would be convinced.However,when placed in the context of the 2004 meta-analysis ,a reasonably possible mechanistic explanation,vitamin D safety in the dose range used, and the importance of falls in the elderly I feel confident that supplementation of 800 U vit. D/day in nursing home residents makes sense. Besides it is necessary for the bones. The meta-analysis was helpful, taking several fairly small RCTs that showed results in the same direction but not all statistically significant and combining them into a composite result that was significant.

Monday, July 04, 2005

American Society Hypertension proposes new definition of hypertension

The American Society of Hypertension (ASH-actually the other ASH, as the American Society of Hematology is also ASH) announced at its recent meeting a new definition of hypertension, criticized ALLHAT and emphasized global risk rather than rigid BP categories. A more precise definition and explanation of ASH's position awaits publication. However, the president of ASH Dr. Thomas Giles of LSU Medical School in New Orleans, said that the new definition incorporates the presence or absence of risk factors and target organ damage markers . The current BP classification uses cut points to define the various stage of hypertension without assessing the patient's actual risk based on other factors. Giles characterizes JNC 7's "prehypertension"as a transitional category and says that if a person with a low BP - in the prehypertension range- has no signs of vascular disease, they should be considered normal.
The ALLHAT trial received criticism as well by Dr. Richard Devereau of Cornell who pointed out some of the methodologic problems with the study. He is certainly not the first to do this:see here and here. The importance of determing global risk of patients and placing BP within that context was a topic discussed at the 2003 ASH meeting and JNC7 was faulted for moving to BP numbers to guide therapy rather than the overall risk assessment approach.
The ASCOT trial ,which showed that the combination of a CCB and an ACEi was superior to the beta blocker-diuretic combination, should prompt a redoing of the JNC recommendation regarding mediation choices. These views of the ASH leader stand in contrast to a recent JAMA editorial. published April 6, 2005.The editorialists say " It is now time to move beyond comparison of diuretics with other classes of BP lowering drugs -that issue has been settled." The issue of the best combination of BP pills is not settled.The ASCOT trial may well bring about a shift in thinking.
Rethinking concepts of disease and treatment is much of what the science part of the art and science of medicine is about.Settled issues have a way of becoming unsettled as we learn more.Stone is a poorly suited medium to record recommendations for treatment.