Even Mild Obesity Linked to Severe COVID-19, Death, in Study

Being even mildly obese could put a person at risk of developing severe COVID-19 and dying, according to a study.

In a paper published in the European Journal of Endocrinology, researchers assessed data on 482 COVID-19 patients who were admitted to the Sant'Orsola Hospital in Bologna, a city in hard-hit northern Italy. The information was collected between March and April, during the peak of the outbreak in the area.

Just over a fifth of the patients had a body mass index (BMI) of 30 or over, meaning they were obese. BMI is calculated by dividing one's weight by the square of their height. A person is deemed severely obese if they have a BMI of 40 or over.

In the study, 20 patients had a BMI of 35 or over. When the team carried out their analysis, 68 patients were still in hospital, so information on how they progressed was not included in the study.

A BMI of between 30 to 34.9 was linked to an increased risk of respiratory failure, and ICU admission. A BMI of 35 "dramatically increases the risk of death," the authors wrote.

Of the patients with obesity, 52 percent had respiratory failure, 36 percent were admitted to the ICU, a quarter needed a ventilator to breathe, and 30 percent died within 30 days of their symptoms first appearing.

Study co-author and bariatric surgeon Dr. Matteo Rottoli, of Alma Mater Studiorum University of Bologna, told Newsweek he knew obesity increased a person's risk of developing other diseases such as type 2 diabetes, cardiovascular diseases and cancer.

During the COVID-19 pandemic he and his team noticed some patients who were particularly unwell were young and obese, and so decided to explore whether their weight or other variables like age, gender and underlying conditions, were risk factors.

"Our study showed that even a mild obesity brings a very high risk," he said.

The main limitation of the study was that most of the patients were caucasian, and those of other ethnicities might have a higher risk of developing severe COVID-19 in the presence of obesity, said Rottoli.

The study partially explains why outcomes vary so much for those who catch the coronavirus, with some having no symptoms and others dying, according to Rottoli. "The metabolic status of the patients has a primary role in the onset and developing of COVID-19, and obesity is the condition that affects the metabolism the most."

Future studies should look at how obesity affects the immune response of those infected with the coronavirus, with the aim of lowering the risk, he said.

Rottoli said people who think or know they are obese should talk to their doctor about the risk of COVID-19. "The importance of social distancing, the use of the masks, and avoiding gatherings should be stressed even more," he said. "We don't know whether losing weight might prevent these risks in people with obesity. However, it is reasonable to think that a healthier person might be able to respond better to the coronavirus infection, and sometimes even losing a few kilograms is enough to improve our metabolic status."

The team cited other studies that have also found a link between COVID-19 and obesity. A pre-print study involving over 4,000 patients in New York City, for instance, found obesity may be one of the biggest risk factors related to COVID-19 hospitalizations and critical illness.

Rottoli also spoke of the difficulty of conducting a study during one of the worst health crises of a generation. "The most challenging part was to deal with the huge impact that this disease had on our healthcare system and our lives," he said. "During the two months of the study, hundreds of patients were admitted to hospital, sometimes with very severe clinical pictures. Some of our colleagues acquired the infection as well. Many patients did not make it. Carrying out the study while dealing with this situation was very hard."

obesity, weight, stock, getty
A stock image shows a person weighing themselves. Scientists have explored the links between obesity and COVID-19. Getty

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About the writer


Kashmira Gander is Deputy Science Editor at Newsweek. Her interests include health, gender, LGBTQIA+ issues, human rights, subcultures, music, and lifestyle. Her ... Read more

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