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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 ...

Thursday, June 18, 2020

If high levels of exercise increase risk of coronary calcification does it also increase CV mortality

Do long time endurance athletes have an increased risk of coronary calcification? If so, does that correspond to an increase risk of cardiovascular events?

In this study (1)  the life long exercisers in the highest activity level (5-6 hours of vigorous activity per week) did show an 11% increase coronary artery calcification (CAC) of a score of 100 or higher but that group had an all cause and cardiovascular mortality risk lower than that in groups with a lower level of exercise.

The author conclusions:

"This study suggests there is evidence that high levels of physical activity (3,000 MET-min/week)are n iassociated with prevalent  CAC but are not associated with increased all-cause 0r CVD mortality after a decade of follow-up, even in the  presence of clinically significant CAC levels."

To the extent these results reflect reality,there may be some reassurance to folks who may have spent arguably too many hours running or cycling.

1) Defina, LF et al. Association of all-cause and cardiovascular mortality with high levels of physical activity and concurrent coronary artery calcification. JAMA Cardiology, 2019 42 (2) P174 (full free text available)

" a man hears what he want to hear and disregards the rest" The Boxer,, Simon and Garfunkel

Tuesday, June 16, 2020

Gain in life expectancy related to exercise not a U shaped curve phenomenon

Moore et al published an analysis of the effect of leisure time activity and the effect on life expectancy with data from over 650,000 individuals with a 10 year followup in persons aged 40 and over.

At the lowest exercise level which was 3.74 met-hr/week ( a MET level of 3 is described by the authors as a brisk walk and this level being equivalent to 75 minutes of brisk walking per week) there was a gain of 1.8 years.

150-300 minutes of a brisk walk per week yielded 3.4 years gained.

300- 449 minutes of brisk walking was associated with 4.2 year increase in life expectancy.

The lowest level at which they demonstrated a life expectancy gain was less than the minimal recommendation of WHO and of the US panel. Benefit seemed to plateau at around 300 mintues of brisk walking per week. Moore's data display was not U shaped.

1) Moore, SC Leisure time physical activity of moderate to vigorous intensity and mortality. Plos Med 2012 e1001 335

2) Aengevaeren,VL Exercise and coronary atherosclerosis. Circulation vol 141 no 16, 21 april 2020 p 1338 1350

Nicholas Taleb schools public health specialists,libertarians and pseudo-libertarians

Nicholas Taleb addresses pubic health "thought leaders", non-devout libertarians and pseudo-libertarians in this commentary regarding the issue of recommending masks for the public.

Some of the points he made include:

1)A significant and vocal and authoritative portion of the public health coterie (PHC) mistook or ignored the important distinction between "absence of evidence of efficacy" and "proof of lack of efficacy".The PHC did not have anything in the second category in their argument tool box. They mistook or ignored the distinction between  absence of evidence and  evidence of absence,something emphasized in epidemiology 101.

2) The PHC failed to recognize how effective the widespread use of mask would be.If A and B both wear masks, both protect the other This Taleb labelled the compounding effect. Witness the hair care business in which 2 stylists were infected and none of the 140 patrons exposed developed covid19. The secret was both the stylists and all of the customers used masks.

3)Libertarians and pseudo-libertarians are admonished by Taleb to remember the primary principle of libertarianism which is the non-aggression axiom. Exposing fellow humans to a serious illness  with whom a person comes in contract just might be considered an act of aggression.

On 6/15/2020 Dr. Fauci admitted that masks were not recommended earlier because there was a serious shortage of masks. Interestingly once masks or face coverings were recommended by the PHC masks of all sorts were available all over the internet. What if the public had been told earlier  that cloth face coverings could help, would there have not been the release of entrepreneurial energy (and charitable efforts) to get masks to people that we see now. Wonder how many deaths could have been prevented.