Recently, the media has reported that people who are obese have a higher risk of hospital admission and death if they are infected with the coronavirus. The government has announced an investigation into which characteristics put people at most risk.

Early reports from China did not flag up obesity as a risk factor. However, people who are very overweight tend to be hard hit by respiratory diseases for a number of reasons. The government warned people who were very obese (with a body mass index of 40 or above) that they were in a high risk category.

Studies from Europe and the US have found that people who were obese seemed to be more likely to be admitted to hospital or to die from Covid-19, and figures from the UK back that up. We don’t know if it is obesity itself that is the problem, or links between obesity and other conditions such as heart disease and diabetes.

Where did the story come from?

The Daily Mail reported that health secretary Matt Hancock had ordered an investigation into links between deaths from COVID-19 and obesity. The review will also look at factors such as ethnic background and sex. The Financial Times said that links between obesity and COVID-19 highlighted the impact of health inequalities in the UK.

What is the basis for the claim?

An analysis of 16,749 patients admitted to UK hospitals with COVID-19 found that obesity was linked to a 37% higher probability of dying, compared to people who were not obese. The risk increased more than four-fold with increasing age over 50 and the more moderate increased risk with obesity was similar to that found with other co-morbidities. The report was published as a pre-print so has not been peer-reviewed yet.

Interviewed on BBC Radio 4’s World at One news programme, one of the researchers said that the results could be explained by:

  • more people with obesity having additional risk factors such as high blood pressure or cardiovascular disease
  • more people with obesity being from deprived areas where they might be more vulnerable to infection
  • people with obesity being more vulnerable to severe infectious disease because of higher levels of inflammation in the body

In their paper, the researchers say: “The recognition that obesity (as recognised by clinical staff) is associated with in-hospital mortality after adjustment for other comorbidities, age and sex has not been widely reported. Obesity was recognised as a risk factor in 2009 for the pandemic A/H1N1 influenza, although not in the 2016 Middle East respiratory syndrome coronavirus (MERS-CoV).”

A study of almost 4,000 hospitalised COVID-19 patients in New York found that obesity was the main risk factor for admission to hospital for people younger than 60. A study in France found that the chances of needing intensive care rose along with body mass index.

What do trusted sources say?

The NHS website says that people are at high risk after contracting the coronavirus if they are “very obese (a BMI of 40 or above)” and that these people should only leave their home if essential to buy food and medicine.

Analysis by EIU Healthcare, supported by Reckitt Benckiser

 

Citation

  1. Docherty AB et al. Features of 16,749 hospitalised UK patients with COVID-19 using the ISARIC WHO Clinical Characterisation Protocol. Available at https://www.medrxiv.org/content/10.1101/2020.04.23.20076042v1 (Accessed 6 May 2020)

Reading list

  1. Science Media Centre. Expert reaction to preprint reporting clinical features of 16,749 hospitalised UK patients with COVID-19. https://www.sciencemediacentre.org/expert-reaction-to-preprint-reporting-clinical-features-of-16749-hospitalised-uk-patients-with-covid-19/ (Accessed 6 May 2020)