Why is there a higher morbidity rate from coronavirus in those with higher BMIs? We spoke to a Consultant Physician (Obesity, Diabetes & Endocrinology) to find out.

About Dr Rajeswaran (Raj)

Raj is speaking on this topic in more detail for healthcare professionals in an upcoming webinar with Oryon Develop. Find out more details and book on by clicking on the button below.

Coronavirus and obesity

March 12th 2020 will go down in history as the date the World Health Organisation declared COVID-19 a pandemic. Nearly six months down the line, medical specialists and scientists have a much broader knowledge of this disease and understand which groups of the population are most at risk should they contract SARS-CoV-2 coronavirus disease (COVID-19). People who are considered obese are in this category and they have been hit disproportionately hard.

“If there is too much body fat, this person will have more inflammatory markers. Since the way that coronavirus works is to trigger inflammation, often obese people will experience a much stronger inflammation leading to complications.”

On 25th June 2020, Public Health England published findings from UK and international reports which all concluded that overweight and obese people had an increased risk of serious illness or even death should they contract COVID-19. Dr Chinnadorai Rajeswaran, who is a Consultant Physician (Obesity, Diabetes & Endocrinology), has a clear understanding of why obesity has become such an important topic during the coronavirus pandemic: “Obesity has always been a hot topic. The UK is the fattest country in the EU, and during the coronavirus pandemic we have seen comparable death rates with the other notoriously fat nations across the pond in the USA. High obesity rates are one major contributing factor to this alarming death rate, so now even more attention is being directed towards the issue.”

Increased risk of complications

The PHE report clearly states that obese people are not at any greater risk of contracting coronavirus but, should they contract it, the consequences can be life threatening. Data clearly shows that overweight people are more likely to be hospitalised, transferred to ICU or even die than their thinner counterparts. This risk grows exponentially as body mass index (BMI) increases. Raj explained clearly why obesity is a risk factor for coronavirus, “Fat is an important endocrine organ, containing adipose tissue that produces hormones in response to signals from other body organs. These are known as inflammatory markers. If there is too much body fat, this person will have more inflammatory markers. Since the way that coronavirus works is to trigger an inflammatory response, often obese people will experience a much stronger infection as a result.”

The government’s reaction

Coronavirus has forced the government to urgently tackle the obesity issue in the UK. On 27th July, the UK government announced a new campaign designed at persuading the British public ‘to lose weight to beat COVID-19 and protect the NHS.’ The government stated that 63% of adults in England are overweight or obese and one third of children are overweight by the time they leave primary school. Obesity is estimated to cost the NHS over £6 billion per annum. Medical issues such as type 2 diabetes, blindness, amputations are increasing rapidly in numbers due to obesity. The medical professionals at the British Obesity and Metabolic Surgery Society are delighted that the British government is finally taking obesity and its problems seriously.

So why does obesity increase morbidity rates?

One study concluded that risk of death from COVID-19 compared with the rest of the population increased by 40% for people with a BMI of 35 to 40 and a massive 90% with a BMI of over 40. Nearly 8% of coronavirus ICU beds have been taken up by people with a BMI of over 40, compared to 2.9% of England’s general population.

“Obese people often already have difficulty breathing, due to an enlarged abdomen compressing their lungs.”

Moving to Europe, the European Centre for Disease Prevention and Control claims that by the end of June this year, 73% of critically ill coronavirus patients in the Netherlands, Switzerland, Sweden, Spain and Italy were obese. Let’s look into why this is.

Reduced respiratory capacity

A serious consequence of obesity, which puts overweight people at serious risk from coronavirus, is carrying excess fat which impacts the respiratory system. As Raj explained, coronavirus triggers an inflammatory response and “this is coupled with the fact that obese people often already have difficulty breathing, due to an enlarged abdomen compressing their lungs.” This impaired lung capacity obviously makes it difficult to clear pneumonia and other respiratory issues and generally hinders pulmonary function.

Patient management

Patient management can be extremely challenging when caring for obese patients. Intubation is often necessary when breathing becomes laboured or impossible but it’s more complex to perform on obese patients and requires experience. It’s also harder to ventilate effectively on people with a high body weight as the lung capacity ratio to body size is low. Therefore if a patient has a serious respiratory infection, it will affect the lungs’ ability to get oxygen into the blood stream.

Raj pointed out another factor that hinders treatment of obese patients who are suffering from coronavirus: “There is also the consideration that obese patients in intensive care are more difficult to pronate (lie on their front). It was quickly found during the early stages of the outbreak that pronating patients increased their ability to breathe and was often lifesaving. However, not only was it very difficult for hospital staff to physically turn over very ill and weak obese patients, but their excess fat also reduced the effectiveness of this technique.”

Diagnostic imaging

Diagnostic imaging can also be an issue in smaller hospitals or hospitals that have a large proportion of obese patients, as they may not have enough equipment suitable for larger people as this specialised equipment has weight limits. Even a shortage of bariatric hospital beds or larger wheelchairs can affect patient care and cause the patient stress and embarrassment.

Pre-existing chronic conditions

Obesity puts an added strain on every organ of the body, so it’s not surprising that obese coronavirus patients often suffer from complications. Raj explains that “obese people often have chronic health conditions, like diabetes, high blood pressure and more.” It’s not only the body’s organs that suffer, excess weight puts stress on bones and joints, and muscle mass shrinks. Obesity can seriously affect mental health and wellness and cause sleep deprivation. Lack of sleep and depression are not conducive to recovery from coronavirus.

Weakened immune system

Science has shown us that our immune system is stronger when we follow a healthy diet and exercise moderately. It has also shown us that obesity weakens the immune system, leaving the door wide open for bacterial and viral infections, such as COVID-19, to enter the body. Another disturbing fact is that some vaccinations are not as responsive on obese people as they are on non-obese people.

To conclude…

Professor John Wilding, who is president of the World Obesity Association, says that a BMI of 30 increases the risk of a hospital related COVID-19 death by between 1.5 and 2 times; a BMI of 40 and over means an increased risk of 2 or more times. Francesco Rubino, chairman of metabolic and bariatric surgery at King’s College London has the final word, “The pandemic really brings to the fore the need to tackle obesity more aggressively. One lesson from the pandemic of COVID-19 is that not treating obesity is not an option.”

About Dr Rajeswaran (Raj)

Raj is speaking on this topic in more detail for healthcare professionals in an upcoming webinar with Oryon Develop. Find out more details and book on by clicking on the button below.

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