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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 ...

Saturday, October 13, 2018

More physical activity may be needed to prevent HF than some other CVD events

 The title is a reworded version of the title of the article which is designated as reference 2 in the footnotes.

There are  2 (at least 2) epidemiologic studies that indicate a linear dose-response relationship between physical activity (PA) and the risk of heart failure. While one study ( Pandy et al see below) does demonstrate a "modest" reduction in HF risk at a lower levels of PA, both studies how a more robust reduction in HF at higher exercise levels.

Pandy et al (Circulation 2015,, see ref 1 below) did a meta-analysis involving about 370  thousand subjects , 20 thousand of which developed HF over a 13 years period.They compared the HF risk in 3 categories based on level of exercise, namely 500 MET-min per week ,1000 MET-min per week and 2000 MET-min per week.

500 MET-min per week is equivalent to 2.5 hours of "moderate" exercise per week or 1.25 hours of "vigorous" exercise per week.Moderate is defined a exercise requiring 3-5.9 MET and vigorous as about 7 METS. (It requires about7 METS to run a 15 minute mile or to finish Stage 2 on the Bruce protocol treadmill exercise tests. One should be able to walk a fifteen minute with a 02 consumption of 5 METS.)

1000 MET-hrs per week is 5 hours of moderate or 2.5 hours of vigorous exercise per week and 2000 as twice that or 10 hours of moderate exercise per week. Yes, that does seem like a lot,

Both the 2008 US exercise  guidelines and the 2018 guidelines recommend at least 500 but state that more benefits accrue with higher levels .

Pandy reported a linear,dose response with a "marked reduction in risk at very high doses of PA ( about 35%) at 2000 MET-min per week".

Their data:
exercise level                                HF RF

500 MET hrs per week                  0.9 (0.87-0.92)
1000 "  " " " " " " " "                       0.81(0.77-0.80
2000 "  "   "   "" """""                     0.65 (0.58-0.73)

Quoting the authors; "Only a moderate reduction ( about 10%) risk in HF noted at the minimal ( US guidelines) recommended level,"

The authors offer a mechanistic explanation namely that CAD event risk occurs at a lower level of exercise by reducing the usual suspect Risk factors (BP,Lipids,blood sugar control) while HF risk reduction occurs at a higher levels of exercise perhaps  by altering cardiac function and structure, i.e beneficial remodeling.

An earlier article Patel K, (Int J Cardiol 2013 see ref 2) had reached generally similar conclusions regarding the levels of exercise needed to decrease HR risk versus the amount adequate to  reduce general  CV risk, e m.gyocardial infarction.

Patel et al studied 5503 patients age 65 and older
During the 13 years of follow up incident HF developed in:
26% of those with little or no regular exercise
23% of those with "low"level of exercise
20% of those with "moderate"
19 % of those with high .

Low was defined a 1-499 Met-min per week
medium as 500-99
high as greater than 1000

The HRs for incident HF were:
low level exercise     0.87 (0.71-1.06)
medium                     0.68 (0.54-0.85) stat sig 
high                            0.60 (0.49-0.74) stat sig 

All exercise level groups had reduced HR for incident MI, stroke, and cardiovascular mortality but the lowest level group did not have a statistically significant  decrease in HR risk.

These 2 studies indicate that more exercise is associated with greater reduction in HF risk, although some HR HF decrease was noted in the lowest exercise group in the Pandy study.

Now for something completely different. A different type of study published by CR de Fillippi from the Cardiovascular Health study ( reference 3) provides an interesting  insight regarding possible mechanism(s) by which more exercise is better in terms of HF risk reduction. 

They studied 2, 9333 subject free of HF at the onset and  who had normal values for two biomarkers, NT-Pro BNP and cTnT (troponin).They then measured these markers every 2 to 3 years and compared incident increase in those markers in groups divided by their exercise levels.(They quantitatedle exercise using  a particular system and used numerical scores to define groups and I was not a to translate those values in to MET hrs to compare with the other 2 articles)

 They found compared with the participants with the lowest PA activity scores those with the highest (i.e. more exercise) had an low odds ratio of 0.50 (0.33-0.77) for a significant increase in NT proBNP and an OR of 0.3 for and increase in troponin.  Quoting  the authors "increased levels of NTProBNP and cTnT may reflect pathological precursors of hemodynamic stress and injury that are prevented by PA at some as yet more precisely defined level.

So how to put all this together.

An  appealing ( at least to me) mechanistic explanation is that an overall decrease in CV mortally and arguably a slight reduction in HF risk  can be brought about by modest exercise and even  perhaps slightly less  than modest levels  by reducing the usual suspect,traditional CVD risk factors.Modest here refers to about 500 MET hrs per week. but some studies have shown a decreased heart attack risk at even lower exercise levels.

A more robust risk reduction in HF risk (perhaps 20-35%) seems  to require higher levels of exercise  ( in the 1000 Met-hrs per week range and higher) by perhaps bringing about an advantageous remodeling of the heart or at least a mitigation of the deleterious remodeling of the heart than occurs with sedentary aging which in turn may predispose to the development of heart failure with preserved ejection fraction (HFpEF).

To the extent that CVD risk factor reduction can decrease heart attacks and the  accompanying reduction in   heart function some reduction in HF risk would be likely, i.e.some reduction in heart failure with reduced ejection fraction ( HFpEF). But at least half of cases of HF are not associated with decreased systolic function ( at least as measured by the ejection fraction  (EJ) but by the echocardiographic finding of decreased left ventricular compliance and distensibility which according to the work of Dr. Ben Levine and others at SW  Medical School in Dallas predispose to diastolic heart failure  (HFpEF) .That group suggests that at least 30 minutes of exercise 4 to five times a week might be sufficient to prevent that age related loss of cardiac compliance. ( see ref 4 below for more on this argument) and perhaps prevent at least some cases of HFpEF.


1)Pandy,A "Linear,dose dependent inverse association between PA(physical activity) and heart failure risk Circ. 115.132 p 1786-1794

2.Patel K. "Prevention of heart failure in older adults may require higher levels of physical activity than needed for other cardiovascular events." Int J Cardiol. 2013, Oct 168 (3) 1905-1909)

3)de Fillippi, CR "Physical activity, change in biomarkers of myocardial stress and injury, and subsequent heart failure risk in older adults. JAm Coll Cardiol.. 2012 Dec. 18;60 (24), 2539-47

4) Bhella, PS  "Impact of lifelong exercise "dose" on left ventricular compliance and distensibility"J Amer coll cardiology. 2014 , 64, no 12,p 1267  



Tuesday, October 09, 2018

2018 U.S. exercise guidelines-or how exercise is good for just about everything

The 2018 Physical Activity Guidelines Advisory Committee issued its report to the Secretary of HHS in February 2018.See here for link to full report.

Their prescription for exercise was unchanged from their 2008 recommendations.  They recommend 2.5 to 5 hours of moderate to vigorous exercise per week. This can also be expressed as 500 to 1000 Met-minutes per week. "Moderate" is defined as exercise requiring between 3 and 5.9 METS and "vigorous" as greater than 6 METS.

To put those numbers into perspective , consider than it would require about 7 METS to run a fifteen minute miles and about 5 METs to walk a fifteen minute mile and about 9 METS to run a 12 minute mile. It requires about 7 METS to complete Stage 2 on the Bruce treadmill protocol .A MET is 3.5 ml of oxygen per kilogram weight per minute. 

Now, about how exercise (physical activity or PA) is good for just about everything. 

The 2008 exercise guidelines reported that PA could lead to a reduction in risk of breast cancer and colon cancer . The 2018 reports adds the following cancers to those whose risk is reduced by PA :
bladder, lung, esophagus, endometrium and stomach.But reduction in heart disease risk is the major selling. point for an exercise program as well as decrease in diabetes and hypertension risk. 


The publication also offers evidence of a risk reduction for dementia and depression.

If the benefits of exercise could be achieved by a daily  pill, everyone would be taking it.








Thursday, September 13, 2018

The impressive and alarming success of the American Board of Internal Medicine Foundation

The American Board of Internal Medicine Foundation (ABIMF) is not the largest,most heavily endowed nor the best known of the many non-profit organizations who  function as advocates for various aspects of health care and medical practice. However, its success in promulgating concepts and influencing medical practice and health care seems disproportionately greater than one might expect based on its size. ABIMF's "greatest" achievement is the development and promulgation of the notion of Medical Professionalism and its major tenets: patient welfare,patient autonomy and social justice. The insertion of the later tenet into medical ethics is a major departure from traditional ethics and is destructive to the physician patient relationship

The first two tenets were long standing pillars of medical ethics and practice and dealt with the relationship between the physician and patient but in 1992, their efforts along with the ACP Foundation and a European Group proclaimed that part of medical professionalism included what they believed was the proper relationship between the physician and society

This  manifesto was published in the Annals of Internal Medicine in 1992 in a paper entitled Medical Professionalism in the New Millennium-A Physician Charter. The ABIF has continued after the 1992 paper to promote the primacy of patient welfare,patient autonomy and social justice and to advocate for "a just and cost effective distribution of finite resources".


 The notion of a co-duty,one to the patient and one to society,was not previously a part of western medical ethics.The 1991 edition of the AMA ethical code did not mention social justice or stewardship of society's resources. Cost effective care is the major thrust of the foundation's recent initiative called "choosing wisely" .  By 2012 over 100 other medical professional organizations had signed on to the Charter and education along those lines apparently is taking place in a number of medical school according to a 2012 article in the Annals of Internal Medicine.

It is the ABIM's MOC  ( Maintenance of Certification program ) that has caused the most angst for internists and reliable reports of its very questionable financial activities have triggered an unprecedented uprising  which surprisingly has had more than a little success.( Much credit for this is due to Dr. Wesby Fisher who on his blog has reported activities of the ABIM and the ABIMF that are  egregious and arguably illegal.)

Yet the sea change in the discussion about medical ethics and professional behavior importantly driven by the same folks who gave us MOC  may in the long run be even more damaging.

Thursday, September 06, 2018

Is the minimal level of recommended exercise sufficient to decrease the risk of heart failure?

In January 2017, I posted a blog commentary entitled " The minimum exercise levels of  the 2008 guidelines won't prevent heart failure". See here.

The gist of that commentary   was that the adherence to the minimal exercise levels indicated by the guidelines had been demonstrated by ample epidemiologic studies to reduce the incidence of cardiovascular disease (CVD) but  exercise at that level had not been demonstrated to reduce   heart failure (HF) incidence and that a higher amount of exercise was needed.

Since then I have more carefully studied a 2015 epidemiologic paper  by Pandy,which I had read before but obviously not with adequate attention , and a detailed physiologic comparison of cardiac function by Bella et al  in 4 groups of healthy subjects who varied  in their long term exercise levels to which I also had not paid appropriate attention. 

These considerations   resulted in a major revision my 2017 headline to " Adherence to the 2008 guideline will reduce HF incidence but more exercise will reduce HF risk significantly more"

Note: I have added an addendum to the 2017 posting  stating the headline is simply wrong 

So now to try and clean up the earlier erroneous  commentary .

First a review of some background:

The 2008 US and WHO guidelines recommend a minimum of 150 minutes of moderate exercise per week or 75 minutes of vigorous exercise. This corresponds to 500 MET minutes  per week or 8.3 MET hours .The US panel also said that further gain could be made by increasing that level to twice that amount. Moderate intensity was defined as requiring between 3 and 5.9 METS and vigorous greater than 6 METS.Note-the panel was addressing the risk of cardiovascular disease in general and not heart failure risk per se .


There is universal agreement that aerobic exercise will decrease heart disease risk ( and according to some studies-dementia,some cancers and type 2 diabetes) but there is disagreement as regards how little exercise  might be  sufficient to reduce cardiovascular risk  and how much exercise might be harmful. I leave those 2  questions  to another time.

In regard to HF:

Patel et (1) published a 2013 review of 5503 subjects age 65 and older from the Cardiovascular Health Study .They divided participants into inactive ,low level exercise ( 1-499 METS),Medium (500 to 999 METS )and high was defined as  greater than 1000 METS 

The hazard ratio (HR) for the low group was a non-statistically significant 0.87 (0.71-1.06,p=0.170.
The medium groups HR 0.68 (0.54-0.85)p=0.001
The high group HR 0.60(0.49-0.74, p=0.026<0 .001.="" p="">

Note that  the low and medium groups overlap the 500 level so  no conclusive verdict regarding HF risk reduction with 500 MET level can be made. You can say that the lowest exercise group enjoyed no reduction in HF risk but we do not know how many subjects were closer to the 1 than to the 500 level. We can say that the medium and high level  did demonstrate a HF  risk reduction but can conclude  nothing about the value of exercising at the 500 MET min level,which is the minimal level recommended by the 2008 panel. 

However, from Pandy's 2015 meta-analysis (2) that there demonstrable risk reduction  in HF in a group of subjects exercising at the 500 MET level. The authors examined data that included over 20 thousand HF events among 370 thousand participants in some 12 prospective cohort studies. 

The 500 MET-min  per week group had a reduction in HF risk ( HR-0.9 (0.81-0.92). However, a greater risk reduction was found in the 1000 MET Min per week group ) HR-.81 (0.77-0.86) and even greater reduction 0.65 (0.58 -0.73 ) in the group at the 2000MET min per week which corresponds to 10 hours of moderate exercise per week or 4 times the minimal amount suggested by the 2008 guidelines.

So the epidemiology  data indicate  that the lower level of recommended exercise will cause a measurable decrease in HF risk but in that regard more does seem to be better.Now to consider Bella's (3) physiological data which is consistent with Pandy's analysis.


 The following  2 paragraphs are copied from my earlier blog commentary.

" Dr Paul Bhella and his  associates  did extensive physiological studies on four groups of healthy volunteers over the age of 64. Four groups were designated   on the basis of their exercise history for the preceding 25 years. (not a typo) 1) sedentary-no more than one exercise session per week  2) casual exerciser-2-3 session per week 3) "committed" exercisers-4-5 session per week and 4)competitive master level athletes -6-7 session per week and competed regularly.  All had normal systolic function ( as defined by a normal resting ejection fraction) but groups one and two has decreased left ventricular compliance while the committed and competitive groups had left ventricular pressure volume curves and left ventricular masses similar to young healthy controls. ( see here for my  further comments and a few caveats regarding this paper including reference to Tanaka's work that challenges the notion that long term endurance exercise  does in fact preserve  ventricular compliance)

Quoting Bhella ". . at least 30 minutes of dynamic exercise per session for 4-5 days per week over a lifetime can  sufficiently prevent most of the decreases in LV compliance and distensibility observed with sedentary aging"

It appears that training at triathlon or marathon levels is not necessary to decrease long term risk of heart failure but the exercise has to be persistent. The term "lifelong "used by Bella may be an exaggeration but his subjects had a 25 year history of regular aerobic exercise.

Bella's data seems to confirm the notion that the 2/12 hours per week recommendation just might decrease the risk of HF with the caveat " if done over a long period of time". The same  group has subsequently published data showing that beginning a  more intense exercise program in a person's 60s or 70's will not result in improved left ventricular compliance but , of course, one would expect  health benefits.

I quote a key paragraph from Bella:

"This study's key finding is the novel observation that at least 30 minutes of dynamic exercise per session 4  to 5 days per week over a lifetime can sufficiently prevent most of the decrease in compliance and distensibility observed  with sedentary aging.This finding holds important implications for global health as ventricular stiffening has been implicated in the pathophysiology of many common CV conditions affecting the elderly.

Contrary to my earlier commentary the minimal levels of exercise may well be enough to decrease the risk of HF but exercise at about twice that levels is likely to bring about a more significant reduction. Note that Bella's comment of 30 minutes 4-5 days a week corresponds to the minimal recommendation of 150 minutes of moderate exercise per week.

1)Patel,K et al Prevention of heart failure in older adults may require higher levels of  physical activity than needed for other cardiovascular events.Int j Cardiol 2013 1905,-1909.

2)Pandy, A Dose Response relationship  between physical activity and risk of heart failure.A meta-analysis. Circulation 2015 132 1786-1794

3)Behlla,P Impact of lifelong exercise "dose"on left ventricular compliance and distensibility. JACC 64 1257-1267 2014  

Wednesday, September 05, 2018

Does the notion that people have a duty to be healthy shatter traditional medical ethics

First lets define what we mean by traditional medical ethics.This would include the medical ethical precepts that constituted medical ethics before the announcement of the "New Professionalism" by the ACP and others. Basically and stating it informally it is that the physician has a fiduciary duty to the patients, and he should place the patients interests before his and of course first do no harm.

Keeping those precepts in mind, consider the following statement which is typical of a growing trend in medical commentaries .

People ( patients) have a duty to be healthy ( practice "healthy behaviors" and eschew "unhealthy behaviors") and comply with medical advice for the good of healthy population.

Drs. JF Wharam and D. Salmasy, writing in the Jan. 14,2009 issue of JAMA. In their discussion of P4P arrangements they state:

...policy makers, health care executives,disease advocates, and scientists with clinical or epidemiological expertise effectively choose population-level goals and thus impose obligations in a manner that
might ( my italics) infringe on patient and physician autonomy. Without fair deliberation,such goals, however wise, cannot claim legitimacy

I suggest that the word "might" be deleted from the above quote. It will infringe. Further, it is not clear what would constitute "fair" deliberation.When someone begins to talk about being fair,watch out.So with "fair deliberation " such claims ( if wise) are , according to the authors therefore  legitimate.



When physicians get some of their income by meeting certain population based goals( e.g. have x% of patients with a hemoglobin A1c under some number) patients who might seem to eat too much or not always take their medicine or whatever else might  be perceived  by the physicians as getting in the way of the population based goals and keeping  the doc from her bonus.Again it is issue of serving two masters,the real life patient in the exam room  versus some insurance based collective construct.

Friday, August 10, 2018

Many Kudos for the anti-MOC warriors and glimmers of hope

Dr. Wes Fisher ,an EP Cardiologist from the Chicago area, has waged what was  for a long while a
one man crusade about the questionable activities of the American Board of Internal Medicine and its own foundation the ABIM foundation and the harmful effects of  their maintenance of certification  (MOC) program. I have blogged a bit about that before and now a number of other physicians have joined in the fray.

Now it seems his prodigious work in that area is beginning to pay off.He recently took part in a very instructive  podcast with Dr. Michel Accad. Fisher is now working with a law firm doing preliminary work hopefully leading to a law suit against the ABIM possibly involving anti trust  issues and fraud.

Money is need for the litigation to move forward.To aid in that effort , Dr. Accad has offered a copy of his brilliant book, "Moving Mountains" to folks who contribute to a fund for the litigation.

Go to the pod cast to learn in details about the antics of the ABIM that catalyzed Dr. Fisher's efforts. See  this link for episode no. 17 of the Accad and Koka Report and links are available there for a GoFundMe link for Fisher's law suit and to the organization he founded, Practicing Physicians of America.
https://practicingphysician.org/


Incidental note. For the last 2 days I have been unable to link to Dr. Fisher's website. I enter drwes.blogspot.com and am diverted to www.widgetserver.com .I was able to backdoor into his site from his Twitter feed.Has his web site been hacked? Coincidence? Addendum , two days later Dr. Fisher's web site was up .


Thursday, July 12, 2018

How well do the Echo guidelines work to estimate cardiac filling pressures ?

Elevated filling pressure is thought to define heart failure as it is thought to be the driver for exercise intolerance and shortness of breath.

Filling pressures can be invasively determined by catheters in either the pulmonary artery wedge position or in the left ventricle.

One of the major aims of echocardiography is to provide reliable estimate of filling pressures .It is generally accepted that echocardiographic indices are more effective in determining  filling pressures in patients with reduced ejection fraction (EF) and is more problematic in patients with preserved EF

The 2009 echo guides  for determination of diastolic function were revised in the 2016 guidelines and both  have been the target of some criticisms.

IMO a 2015 article ( 2) from the Cleveland Clinic offers data that raises reasonable concerns about the estimation of filling pressure in patient with preserved EF.It should be noted that the classification system of degrees of diastolic dysfunction (DD) used by the authors is not the exact system proposed by the 2016 guidelines. but rather those of the 2009 guidelines.(1) and the authors' criticism relate specifically to the 2009 system.However I believe their conclusion ( see below) regarding the basic underlying paradigm holds regardless of tweeks made to the 2009 guidelines.

The authors reviewed 460 consecutive patients who underwent echocardiography within 24 hours of elective left heart catheterization.

Their figure 5 plots left ventricular diastolic pressure (LVEDP) against normal and the 3 grades of DD in patients with EF greater than 50 % and those with EF less than 50%.In both groups there was no difference in LVEDP between normals and those with Grade 1 and Grade 2. The only statistically significant difference was that between normals and those with grade 3  DD who had EF less than 50%.

The authors conclude: "the findings of this study question the notion that DD is a predictable, progressive process beginning with impaired relaxation followed by reduced compliance and increased filling pressures. The prognostic value of echo graded DD may relate more to its reflection of intrinsic properties of the left ventricle, or to exercise hemodynamics  than to its correlation with resting hemodynamics alone. "A Mayo Clinic study  of 467 patients ( 3) by Kane et al found  no higher pulmonary artery systolic pressures at rest  or on  exercise in those patients with the echo diagnosis of impaired relaxation.



 1) Nagueh, SF Recommendations for the evaluation of left ventricular diastolic function by echocardiography. J Am Soc Echo 2009, 22, 107


2) Grant A, Grading diastolic function by echocardiography:hemodynamic validation of the existing guidelines. Cardio Vascular Ultrasound 2015.


3)Kane, GC et al Impact of age on pulmonary systolic pressure at rest and with exercise.Echo Research and Practice, 2016,3(2) 53-61


addendum 8/1/18 spelling errors corrected and several poorly worded sentences revised.