The COVID-19

​
​Wei Perng, PhD

In the short time since the novel coronavirus COVID19 has taken the U.S. by storm, more than 80% of Americans are now waking up to a “new normal” in which we cannot go to work or school outside our home. If we do venture out, we are advised to wear cloth masks and stay at least six feet away from others.

Amidst these major changes to our daily lives, I’ve been noticing friends and coworkers grumble about how they won’t be able to fit into their work clothes when this all ends since they can’t go to the gym. “Instead of the Freshman 15, we will gain the COVID 19,” my mother-in-law joked. While this is potentially true (and rather unfortunate), I have been more preoccupied with another relationship between the virus and excess weight: it appears as though persons with overweight or obesity are more likely to suffer complications of COVID19, even if they are otherwise healthy.  

​At the beginning, the only evidence I came upon was anecdotal. I heard from a colleague who works in the ER that a 33-year-old is on a ventilator. “He’s healthy,” she said, “and doesn’t smoke. No history of asthma, bronchitis, or any other medical complications… oh, but he is overweight.” As my curiosity grew, I began scouring the internet and realized that because the pandemic evolved so quickly, the articles I came across could only allude to data that had not yet been published (e.g., this article in the New York Times). Just this week, I found a hot-off-the-press paper published in Clinical Infectious Diseases. (Note that this paper was published and made available so swiftly that the hyperlink takes you to a PDF manuscript draft rather than a polished galley proof formatted for a journal.)  In this retrospective registry-based analysis of 3,615 individuals who presented to a large academic hospital in New York City and tested positive for COVID19, the authors found higher risk of complications (defined as requiring intensive care accommodations or a ventilator) among patients <60 years of age with obesity. Despite coming up relatively short-handed on hard evidence (i.e., just one published paper showcasing simple unadjusted associations to support my hypothesis), I am relieved to see peer-reviewed research trickling through on this topic, especially since there are some plausible biological explanations regarding why excess weight would make COVID19 worse:

• Obesity is characterized by a low-grade inflammatory state, and inflammation is thought to play a role in worsening COVID-19 outcomes. This is evidenced by the ongoing COLCORONA trial to test the effect of the anti-inflammatory drug colchicine on COVID19-related lung complications and death.
• Excess fat mass – especially around the core of the body – can compress the lungs and diaphragm. Given that COVID19 is a respiratory disease, any interference with lung function or respiratory capacity could worsen prognosis.
• Even if a person with obesity is free of other medical complications, it is likely that they have subclinical alterations to health and metabolism. For example, diabetes patients are considered a high-risk subgroup for the virus since it can be harder to treat any illness due to fluctuations in blood sugar. Moreover, the virus is purported to thrive in an environment of elevated blood glucose. Given that the relationship between body mass index (BMI) and glucose-insulin homeostasis exists across a continuum – even in the absence of frank diabetes, a person with overweight or obesity who does not meet criteria for diabetes likely still has elevated blood glucose levels. (NB: for those who are type 1 diabetic, immunosuppression directly contributes to their vulnerability – a distinct issue from that of obesity.)

What does this mean? First off, this is a point of concern for the U.S., which ranks #1 in the world for prevalence of obesity. Secondly, this could have ethical implications for the already complex and arduous process by which health care workers must determine who receives precious resources. For instance, if an obese person and a non-obese person of similar age and medical history present to an overburdened ER, who would have priority for care? I imagine that in the upcoming weeks, we will gain a clearer picture of these intricacies.