#OBSM August 2020 Chat: Obesity and COVID-19

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#OBSM Chat: Obesity and COVID-19

August 2020

Written by: Neil Floch, MD

COVID-19 struck China and the globe watched with disbelief as the virus invaded Europe and then North America and the world. When the COVID-19 pandemic began, researchers found that risk factors such as older age, male sex, hypertension, diabetes, cardiac disease and history of malignancy were more common in sicker and dying patients. (1)(2)(3) The first studies did not reveal that patients with a higher BMI were at an increased risk of contracting the virus or having a worse response to an infection. (4)(5)(6) 

As COVID-19 spread, reports revealed that people with obesity became sicker after being infected. The risk of needing to be placed on a ventilator was 7 times higher in hospitalized patients with a BMI greater than 35 compared to people with a BMI less than 25. (7) Worse disease in COVID-19 infected patients and need for placement on a ventilator was found to increase when BMI increased above 35. These findings were independent of age, sex, diabetes, or hypertension in this French study. (7)

Initial experience in our institution in Connecticut (see tweet) as well as information from studies in New York City showed that younger patients with obesity were much more commonly affected than young patients generally.  Patients less than 60 years old with a BMI between 30-34 and > 35 had 1.8x and 3.6x risks of being admitted to the ICU. (8)

Another French study demonstrated that citizens with obesity were much more likely to develop an initial infection with COVID-19 than those of normal weight. (9) These findings led the French government to recommend that citizens with obesity stop working to reduce their risk of contracting the virus. (10)

Although there is no direct proof why patients with obesity are more likely to be infected with COVID-19 and have a worse outcome, several hypotheses exist. Patients with obesity have a weaker ability to breathe than people of lower weight. They have a decreased expiratory reserve volume, decreased functional capacity, and lower pulmonary compliance than individuals of normal weight. In other words, their lungs do not work as efficiently to bring in oxygen and breathe out carbon dioxide. When lying flat, people with obesity have more difficulty breathing than people of lower weight. (11) An increased amount of fat or adipose tissue is associated with a weaker immune response, and an elevated level of cytokines, or toxic molecules that are released during an infection. (12). These molecules destroy the lung tissue and airways when released in large amounts. (13)(14) Adipose tissue contains ACE2 receptors, which have been found to bind the SARS-COV-2 virus, allowing it entry into a patient’s cells.  It is unclear whether the increase in physical size or the inflammation associated with obesity is more accountable for the poorer outcome associated with the virus. Obesity is also associated with many of the chronic diseases that are also associated with a poor outcome such as diabetes and hypertension.

A preliminary French study on COVID-19 and bariatric surgery performed by Antonio Iannelli MD, showed that:

People with obesity and a COVID-19 infection that underwent bariatric surgery in the past had a reduced risk of needing to be placed on a ventilator and death from a COVID-19 infection when compared to people with COVID-19 who did not have weight loss surgery. Bariatric surgery is believed to improve the mechanics of lung function by causing weight loss and reverse the low-grade systemic inflammation that occurs in people with obesity. (15)
Although many mysteries surround the COVID-19 virus, there is evidence that patients with obesity are at a higher risk of becoming infected and having a worse overall outcome. Thus, people with obesity must take precautions to prevent infection from the virus, such as social distancing and wearing a mask in public. Obesity is an inflammatory disease and governments, physicians, and patients themselves must take steps to prevent and treat this disease. 

During this month’s tweet chat, we’ll discuss the following questions:

1. What is the risk of having obesity and Covid-19? What do the studies show?

2. Why does obesity create a risk of both contracting COVID-19 and doing worse with the disease?

3.  What resources have been helping you (or your patients) reduce the risk of contracting COVID-19? 

4. Due to the link to COVID-19, Britain has waged a campaign to reduce obesity by limiting advertising of high sugar and fat foods to children, stopping BOGO sales of unhealthy foods, and encouraging GPs to address these issues. What are the pros and cons of this attempt to decrease obesity in the UK?

5. What lessons can be learned from the COVID-19 pandemic concerning the disease of obesity and how patients with it are treated worldwide?
(1) Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet Lond Engl. 2020;395(10223):497-506.

 (2) Zhou F, Yu T, Du R, et al. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet Lond Engl. 2020;395(10229):1054-1062.

 (3) Shi Y, Yu X, Zhao H, Wang H, Zhao R, Sheng J. Host susceptibility to severe COVID-19 and establishment of a host risk score: findings of 487 cases outside Wuhan. Crit Care Lond Engl. 2020;24(1):108.

 (4) Li Q, Guan X, Wu P, et al. Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Infected Pneumonia. N Engl J Med. 2020;382(13):1199-1207.

 (5) Grasselli G, Zangrillo A, Zanella A, et al. Baseline Characteristics and Outcomes of 1591 Patients Infected With SARS-CoV-2 Admitted to ICUs of the Lombardy Region, Italy. JAMA. Published online 06 2020.

 (6) Bhatraju PK, Ghassemieh BJ, Nichols M, et al. Covid-19 in Critically Ill Patients in the Seattle Region - Case Series. N Engl J Med. 2020;382(21):2012-2022.

 (7) Simonnet A, Chetboun M, Poissy J, et al. High Prevalence of Obesity in Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) Requiring Invasive Mechanical Ventilation. Obes Silver Spring Md. Published online April 9, 2020.

(8)  Lighter J, Phillips M, Hochman S, et al. Obesity in patients younger than 60 years is a risk factor for Covid-19 hospital admission. Clin Infect Dis Off Publ Infect Dis Soc Am. Published online April 9, 2020.

 (9) Caussy C, Pattou F, Wallet F, et al. Prevalence of obesity among adult inpatients with COVID-19 in France. Lancet Diabetes Endocrinol. Published online May 18, 2020.

(10) DGOS_Michel.C, DGOS_Michel.C. Obésité et Covid-19. Ministère des Solidarités et de la Santé. Published June 15, 2020. Accessed June 16, 2020. http://solidarites-sante.gouv.fr/soins-et-maladies/prises-en-charge-specialisees/obesite/article/obesite-et-covid-19

(11)  Dixon AE, Peters U. The effect of obesity on lung function. Expert Rev Respir Med. 2018;12(9):755-767.

(12)  Huttunen R, Syrjänen J. Obesity and the risk and outcome of infection. Int J Obes 2005. 2013;37(3):333-340.

(13)  Zhang X, Zheng J, Zhang L, et al. Systemic inflammation mediates the detrimental effects of obesity on asthma control. Allergy Asthma Proc. Published online October 2, 2017.
(14)  Jose RJ, Manuel A. Does Coronavirus Disease 2019 Disprove the Obesity Paradox in Acute Respiratory Distress Syndrome? Obes Silver Spring Md. 2020;28(6):1007.

(15) Askarpour M, Khani D, Sheikhi A, Ghaedi E, Alizadeh S. Effect of Bariatric Surgery on Serum Inflammatory Factors of Obese Patients: a Systematic Review and Meta-Analysis. Obes Surg. 2019;29(8):2631-2647.

Latest Transcripts

While each monthly chat is only an hour long, tweets are archived for later review

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09 Aug, 2020

#OBSM Chat: Obesity and COVID-19 August 2020

#OBSM Chat: Obesity and COVID-19 August 2020

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