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Thursday, March 26, 2020

We're not shooting in the dark

1. On the one hand, the coronavirus (i.e. SARS-CoV-2/COVID-19 or simply COVID-19) is a novel virus. That poses many challenges for us. For example, take the fact that it's constantly mutating. Indeed, there are at present approximately two different groups of the coronavirus - i.e. L and S haplotypes. As such, its virulence and transmission can shift over time in unpredictable ways. In fairness, the coronavirus seems to be reaching some genetic stability now. Hopefully it won't significantly change before we can find a vaccine. (By the way, if anyone wishes to see the mapping of the various strains of the coronavirus' genomic evolution, this website is a good resource.)

2. On the other hand, the leading disease that's killing people from coronavirus is acute respiratory distress syndrome (ARDS). Yet ARDS is an utterly familiar disease to physicians today. In other words, yes, we have to wait for therapies like antivirals and vaccines for the coronavirus. However, it's not as if we're wildly shooting in the dark. We know how to treat ARDS. We know how to protect the lungs. We know how to intubate patients. We know how to put patients on mechanical ventilation. We know how to prone people early to help increase their survival chances. We know how to use empiric antibiotics. We know how to use inhaled prostacyclins and neuromuscular blockers. We know the seven Ps for the care of ARDS patients. Indeed all these (and other) strategies work very well for ARDS.

3. It's just that, even absent the coronavirus, ARDS has high mortality rates:

ARDS is associated with appreciable mortality, with the best estimates from a multicenter, international cohort study of 3022 patients with ARDS, suggesting an overall rate of death in the hospital of approximately 40 percent [1-4]. Mortality increases with disease severity; unadjusted hospital mortality was reported to be 35 percent among those with mild ARDS, 40 percent for those with moderate disease, and 46 percent for patients with severe ARDS [4].

14 comments:

  1. What is it about this whole thing that's so hard on the lungs of really old people, and somewhat, even significantly less harmful to younger folks (co-morbidities notwithstanding)?

    I've heard somewhere (and it was a doctor on TV somewhere) that this happens because older people have developed so many more immunities in their lives, just from having dealt with so many colds and flus, that their older and much more sensitive immune systems just really over-react when this virus is present, and it tears up their lungs more than even the virus does.

    That makes sense to me, given my super-limited understanding of how the cascade of interleukins works when infections and inflammation are present.

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    1. There's a lot to unravel:

      1. If you watch anything on the mainstream media, it's almost always poorly informed from a medical scientific perspective. That goes for any news outlet. CNN, MSNBC, even FOX.

      2. Interviews with experts are better, but the problem is that interviews aren't usually given much time. A 5 or 10 minute interview can't get much across.

      3. Many experts may be intelligent and accomplished, but they're not always great communicators. In fairness, it's hard to convey a complicated idea in a one minute sound bite. There are some exceptions such as Scott Gottlieb who is quite informative even given time restrictions.

      4. I think the old people vs. young people thing is something of a myth the media may have popularized. There are young people who have died from the coronavirus. There are old people who have survived.

      5. Also, even if a person doesn't die, it's not exactly easy to undergo hospitalization let alone admission into the intensive care unit, which many young people have undergone. This even includes children under age 10, even though the popular idea seems to be that kids can't get the coronavirus (false).

      6. However it is true older people have died at significantly higher numbers and rates than younger people. According to CDC data, approximately 80% of deaths occurred in those aged 65 years or older.

      7. As I mentioned, the leading cause of death from coronavirus is ARDS. It's not that ARDS is hard only on old people's lungs. ARDS is hard on anyone's lungs.

      8. However even healthy older people tend to have less "robust" lungs than younger people so to speak. Just look at the average 60 year old running a mile vs. the average 20 year. Hence if the older person gets a respiratory illness, especially one as serious as ARDS, then it tends to be "harder" on their lungs because they're lungs (to say nothing of the rest of their bodies) don't tend to have as much "in reserve" as it were.

      9. Anyone of any age who has comoribidites is more likely to have poorer clinical outcomes if they develop ARDS than if they were free of comorbidities. However comorbidities (even if undiagnosed) such as high blood pressure and diabetes tend to be more prevalent among older people than among younger people.

      10. Of course some younger people do have comorbidities too (e.g. type 1 diabetes, cystic fibrosis). If they did, then it would make it more likely for them to have poorer clinical outcomes as well if they developed ARDS.

      11. It's true there's growing evidence that some if not many patients who are infected with the coronavirus respond to it with what's known as a cytokine storm (with features of sepsis and hemophagocytic lymphohistiocytosis). Presumably this is what you're referring to when you're referring to "the cascade of interleukins" and so on.

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    2. 11. It's true there's growing evidence that some if not many patients who are infected with the coronavirus respond to it with what's known as a cytokine storm (with features of sepsis and hemophagocytic lymphohistiocytosis). Presumably this is what you're referring to when you're referring to "the cascade of interleukins" and so on.

      This is what I heard. These cascading cytokines also have a positive function -- have you read "Younger Next Year"? -- there's apparently a "tearing down" function, and also a "rebuilding" function with these cytokines. It seems to me that older folks simply do not have the physical resources to "bring on" the rebuilding function. Dr Henry Lodge described these (in layman's terms) as C-6 and C-10. In his view, the proper kind of exercise manipulates these two functions, which, if done properly, can function as a sort of fountain of youth in our lives. It interests me because the "C-10" function comes from the exercise of muscles (and are generated from there?) -- the problem is that people over 80 generally have no muscles left, because of the process of sarcopenia.

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    3. Hm, there's a lot more to respond to, but I think it's moving away from the original post. So I'll just leave it alone.

      I've never read Younger Next Year.

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    4. I understand. I agree that my comment here is very simplistic. Henry Lodge admitted that his explanation was greatly simplified. I'm just trying to make connections.

      "Younger Next Year" is a wonderful book.

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    1. 1. I’ve never used Ferguson’s model.

      2. Also, I’m not on “team apocalypse”. In fact, I’ve criticized “prophets of doom”. Search my past posts.

      3. And in fact this very post offers hope inasmuch as I said we know how to deal with the leading cause of death among coronavirus patients in the ICU, i.e. ARDS.

      4. So I don’t see why you’re putting this article here.

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    2. I merely posted it as a related FYI for anyone who is interested. No deeper motives were intended. I didn't suggest you were on "team apocalypse".

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    3. Well, that’s what the article says. Otherwise I’m not sure why you’re putting this particular article here rather than in other posts about the coronavirus. Or better yet simply starting your own new post since you’re a Triablogue member for now.

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    4. I thought we were having a decent conversation here, and as you say, this post offers hope, and the article offers hope, and that's the common thread (I have thought). It is easier to comment on an existing article that's still near the top, than to post a new one (pushing a good and current article down the page).

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    5. Given our recent history (your words and actions toward me on email and FB which explicitly state to me that you’ll be “avoiding” me and in which you’ve evidently temporarily blocked me, which is your prerogative), it sounds more like you’re sending mixed signals.

      “Hope” as a “common thread” is thin. You could say your previous post was about “hope” and simply posted your link there. Likewise you could have posted your link in the coronavirus post that’s actually currently at the top of Tblog’s front page (hint: it’s not this post or any of my posts).

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    6. Keep in mind this article you link to is about how an epidemiologist had to significantly revise his projected numbers. And keep in mind you’ve been consistently minimizing the coronavirus pandemic. And keep in mind you’ve criticized me and others for trying to be more realistic. And keep in mind you’ve sent me numerous unsolicited emails about all this. So it’s hardly unreasonable for me to question why you’re posting this article here and now as well.

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    7. In the spirit of "keeping lines of communication open", I sincerely thought that since you and I were discussing things here, this would be a good place to keep discussing things.

      The C-6/C-10 discussion that Henry Lodge wrote about in "Younger Next Year" has genuinely fascinated me, and I know you are aware of my interest to write about the benefits of strength training for older folks. When you wrote about ARDS, I took the opportunity to ask a question about an ongoing interest of mine, where there seems to be very little public information available. (Dr Lodge did not elaborate for anyone who had deeper medical interests than what he provided). And I very much appreciate your response to my question.

      I seem to be much less focused than you are on "where certain things should be posted", and instead (in the midst of a busy day) go to the last point where there was a communication connection. I'm sorry about sending "mixed signals". As I say, I thought we were having a decent conversation here, and I wanted to build on it.

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    8. It’s hard for me to have a reasonable conversation with someone who keeps behaving in unreasonable or inconsistent or at least mercurial ways. In email you use strong and even harsh language toward me, but on Tblog you’re more restrained and respectful. On FB you temporarily block me (“take a break” from me), but on Tblog you change your tune and want have a “decent conversation”.

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