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#Obesity and #COVIDー19 have been in the headlines recently.
The link between the two is now undeniable.
Let’s take a look at WHY they are so tightly linked molecularly, physiologically, and anatomically in this #tweetorial.
#medthread #medtwitter
nytimes.com/2020/04/16/hea…
#Obesity and #COVIDー19 have been in the headlines recently.
The link between the two is now undeniable.
Let’s take a look at WHY they are so tightly linked molecularly, physiologically, and anatomically in this #tweetorial.
#medthread #medtwitter
nytimes.com/2020/04/16/hea…
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We learned quite a bit about obesity and viral infection in 2009 during the #H1N1 epidemic. Obesity led to:
🔼risk of ICU admission
🔼viral shedding
🔼recovery times
But WHY?
ncbi.nlm.nih.gov/pmc/articles/P…
We learned quite a bit about obesity and viral infection in 2009 during the #H1N1 epidemic. Obesity led to:
🔼risk of ICU admission
🔼viral shedding
🔼recovery times
But WHY?
ncbi.nlm.nih.gov/pmc/articles/P…
The story is complex, but inflammation plays a critical role.
Individuals with obesity are in a state of chronic low-grade inflammation as evidenced by altered levels of several cytokines such as TNFα, IL-6, and CRP.
ncbi.nlm.nih.gov/pubmed/22429824
Individuals with obesity are in a state of chronic low-grade inflammation as evidenced by altered levels of several cytokines such as TNFα, IL-6, and CRP.
ncbi.nlm.nih.gov/pubmed/22429824
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The adipocyte appears to be the protagonist in all of this.
As adipocytes hypertrophy, they drive further secretion of cytokines, adipokines, and fatty acids, creating a dangerous feedback loop that leads to insulin resistance and chronic inflammation.
The adipocyte appears to be the protagonist in all of this.
As adipocytes hypertrophy, they drive further secretion of cytokines, adipokines, and fatty acids, creating a dangerous feedback loop that leads to insulin resistance and chronic inflammation.
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It is no surprise then that obesity, COVIDー19, and #cytokine storm are so tightly linked.
Unfortunately, the same cytokines that can lead to poor outcomes are those that are up-regulated in obesity.
forbes.com/sites/claryest…
It is no surprise then that obesity, COVIDー19, and #cytokine storm are so tightly linked.
Unfortunately, the same cytokines that can lead to poor outcomes are those that are up-regulated in obesity.
forbes.com/sites/claryest…
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Normally, adipocytes and immune cells work together.
In obesity, this balance is disrupted, leading to dysregulation.
This is seen most prominently in the switch from M2 to M1 macrophage phenotype and B-cell class-switching from IgM to IgG.
ncbi.nlm.nih.gov/pubmed/28045397
Normally, adipocytes and immune cells work together.
In obesity, this balance is disrupted, leading to dysregulation.
This is seen most prominently in the switch from M2 to M1 macrophage phenotype and B-cell class-switching from IgM to IgG.
ncbi.nlm.nih.gov/pubmed/28045397
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Can weight loss reverse these effects?
Yes, although the exact mechanism is unclear.
In one review of 66 studies, weight loss led to 🔽cytokine inflammatory markers and 🔼adiponectin.
The effects were most pronounced for weight loss of > 10%.
ncbi.nlm.nih.gov/pubmed/19087366
Can weight loss reverse these effects?
Yes, although the exact mechanism is unclear.
In one review of 66 studies, weight loss led to 🔽cytokine inflammatory markers and 🔼adiponectin.
The effects were most pronounced for weight loss of > 10%.
ncbi.nlm.nih.gov/pubmed/19087366
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Putting molecular biology aside, obesity also presents anatomical and physiological challenges.
An obese abdomen pushes up on the diaphragm, reduces chest wall compliance, and raises intrapleural pressure, resulting in atelectasis and V/Q mismatch.
Putting molecular biology aside, obesity also presents anatomical and physiological challenges.
An obese abdomen pushes up on the diaphragm, reduces chest wall compliance, and raises intrapleural pressure, resulting in atelectasis and V/Q mismatch.
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This respiratory compromise is seen more frequently in the supine position, arguing for prone ventilation, among a host of other techniques and settings designed for patients with obesity.
ncbi.nlm.nih.gov/pubmed/30850002
This respiratory compromise is seen more frequently in the supine position, arguing for prone ventilation, among a host of other techniques and settings designed for patients with obesity.
ncbi.nlm.nih.gov/pubmed/30850002
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While this #tweetorial just scratches the surface on the interplay between obesity, the immune system, and ICU-level care, it underscores how obesity is a disease with complex molecular, physiological, and anatomical underpinnings.
While this #tweetorial just scratches the surface on the interplay between obesity, the immune system, and ICU-level care, it underscores how obesity is a disease with complex molecular, physiological, and anatomical underpinnings.
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Short of a vaccine and best practices regarding social distancing and personal hygiene, weight loss appears to be an important strategy for providers and patients to consider in the era of COVIDー19.
Short of a vaccine and best practices regarding social distancing and personal hygiene, weight loss appears to be an important strategy for providers and patients to consider in the era of COVIDー19.
