Obesity, stigma and vulnerability to Covid-19

Weight alone is no predictor of coronavirus risk: obesity must not be used to discriminate

British prime minister Boris Johnson: Assertions his excess weight made his Covid-19 illness worse than his leaner colleagues are unfounded. Photograph: Chris J Ratcliffe/Getty

One of the interesting things about Covid-19 is that it affects some people worse than others. A major challenge for public health experts is to identify which factors drive that variation.

Older patients do worse, as do those who’ve had recent surgery or “underlying medical conditions”. In the scramble to publish information about predicting Covid-19 severity, scientists have found that patients with severe obesity are more likely to need hospital admission, intensive care and to go on a ventilator than those with normal body weight.

However, we can’t apply these findings to everyone who is overweight or obese. You need to know how tall someone is to calculate their body mass index (BMI) and in frantically busy hospitals around the world in the past few weeks, height measurement may have understandably been a low priority for clinicians. So, studies to date have only found a higher risk from Covid-19 for patients in hospital with a very high BMI (above 35 units). While it may seem likely that overweight confers higher risk, it will take time and research to answer this question properly.

Given the limited information we have, was the recent assertion justified in a Sunday newspaper that Boris Johnson’s excess weight made his Covid-19 illness much worse than that suffered by his leaner colleagues? Hardly.


Inflammation and metabolism

While overweight and obesity can appear obvious, it is impossible to predict BMI just by looking at someone, or to tell how much of their weight is made up of fat and lean tissue. Much more important risk factors such as diabetes, high cholesterol and blood pressure need to be considered, but aren’t readily apparent. Also, scientists are beginning to understand that the relationship between obesity and Covid-19 severity has less to do with the mechanical effects of the excess tissue and more to do with how it affects inflammation and metabolism. How big someone looks on television is not a good way of telling whether they’ll need intensive care for Covid-19.

Public commentary on this issue needs to be informed and accurate. It also needs to be balanced with an awareness of the level of stigma that those with obesity already experience. Assumptions about obesity risk ignore “confounders” such as income, environment, resourcing, health-seeking behaviours and obesity stigma.

Thin people die from Covid-19 too.

Psychological damage

The moral judgment faced by those suffering with obesity can individualise the challenge of risks such as Covid-19 and be psychologically isolating. Assertions that obesity is an easily modifiable personal lifestyle choice are harmful and ineffective and contrast with discourse related to people with cancer or HIV, for example. Speculation that people with obesity are more likely to be asymptomatic carriers with a higher chance of infecting others is without any scientific basis whatsoever, but may be particularly harmful if it further increases stigma towards affected individuals. Given the reality of stigma and the risks to those with severe obesity, it would be good to see policies expressed explicitly to ensure that this vulnerable group is not discriminated against in work or health contexts.

The "responsibility" theme could be turned on its head here. Many of those worst affected by obesity in Ireland have been languishing on hospital waiting lists for obesity treatments. The provision of that care may have reduced the risk posed to them now by coronavirus.

It is a pity that the mobilisation of the State’s public health apparatus wasn’t as decisive, proportionate and effective for the obesity crisis as it has been for Covid-19.

Dr Finian Fallon, psychologist, St Vincent’s Healthcare Group, Dublin; Prof Carel le Roux, physician, St Vincent’s Healthcare Group; and Prof Francis Finucane, consultant endocrinologist, Galway University Hospitals