We spoke with obesity expert Prof Francis Finucane from NUI Galway, on why people living with obesity are at increased risk of more severe illness if they contract Covid-19.

One of the many mysteries that still surround COVID-19 is why some people who contract the illness suffer more severe symptoms than others.

It’s important to remember that the majority or 80 per cent of people who get COVID-19 suffer a mild flu-like illness that can be successfully managed at home.

However, other groups such as the frail elderly and those with underlying conditions are at increased risk of more severe disease and death.

People living with severe obesity (BMI of over 35) are part of the at-risk group, and while they don’t seem to be at an increased risk of contracting COVID-19, if they do get it, they are at increased risk of being hospitalised, admitted to ICU and sadly dying from the virus.

Professor Francis Finucane is a Consultant Endocrinologist at Galway University Hospital and Honorary Professor of Medicine at NUI Galway; he also has a specialist interest in obesity.

According to Prof Finucance, while research to date has confirmed the increased risk from COVID-19 in those worst affected by obesity, it isn’t yet clear if the risk applies to those with a BMI under 35.

“It may just be that the problem is so new that those data aren’t available yet. For now, it seems sensible to regard excess weight as a marker of risk, and the more excess weight there is, the higher we suppose the risk will be. But it would be nice to confirm whether or not this is true in large studies in different populations so that we can work out how best to identify those who might be worst affected. “

“That may just be because we haven’t done enough studies. It seems likely that if severe obesity confers a very high risk and it does, then there is probably a dose dependent effect. It is probable that any obesity is bad and any obesity confers risk but that just hasn’t been shown yet. This is a new disease that first emerged in December 2019. We are very much trying to catch up and learn as much as we can about the apparent relationship between overweight, obesity and COVID-19 severity.”

Prof Finucane said it was critically important to understand and identify patients who are at particularly high risk from severe COVID-19 so healthcare professionals can intervene earlier in people who may have significant illness.

So why are people living with obesity at increased risk of more severe illness if they contract COVID-19?

Prof Finucane explained that often people with obesity are also living with other conditions that in themselves, put individuals at increased risk of more severe disease in COVID-19. These include diabetes, high blood pressure and cardiovascular disease.

“All of these are factors that are independently and more strongly associated with COVID-19 risk than someone’s body mass index category alone. So I think we need to focus on these other factors which are probably the reason why people with significant excess body weight are at higher risk from COVID-19,” he said.

While people living with severe obesity are increased risk of more severe illness if they contract the coronavirus, Prof Finucane said studies have suggested that this may be due to metabolic rather than mechanical factors.

This means that it is unlikely that people with obesity will have increased difficulty breathing for example due to excess weight on the lungs or the chest but that rather something else was at play. Intensive care specialists have noticed that the problem is not with getting oxygen into the lungs, but with getting it from the lungs to the blood.

“It’s really important that we don’t just look at an individual and say well because that person appears to me to be overweight, just eyeballing them or looking at them on the television, then they are of high risk, that is really over-simplistic and unhelpful,” Prof Finucane said.

While it doesn’t seem that the physical effect of excess weight on the body is to blame for more increased risk of severe disease in people with obesity, what does seem to be involved are inflammation and insulin resistance.

When under attack from a virus the body emits an inflammatory response in an effort to fight infection. However, in obesity this inflammatory response is heightened due to cells in excess fat tissue, causing a more severe inflammatory reaction in the lungs.

Insulin resistance is a condition that occurs when the body doesn’t use the insulin it produces properly.

Prof Finucane explained that insulin resistance was associated with diabetes and overweight and obesity as well as cardiovascular disease and means that the metabolism is not working very well.

He suggested that this deficit might make it easier for the COVID-19 virus to get into the lungs resulting in more severe disease in patients with obesity. Prof Finucane has recently published a paper on this in the journal Frontiers in Public Health (published: 12 May 2020 doi: 10.3389/fpubh.2020.00184) )

“What we think might happen is insulin resistance, through working on the receptors and cells, makes it easier for the virus to get into lung cells. That is an idea and it is speculative but it would account for the variation in severity that we see in patients who have obesity, “ he explained.

While we are still learning about why people living with obesity are more likely to get more severe symptoms of COVID-19 and as mentioned above, it may be because some individuals with overweight and obesity may also have heart disease, diabetes or high blood pressure, Prof Finucane said it was important to note that people who are normal weight also get type 2 diabetes and there are many people living with overweight and obesity who are “perfectly healthy in every other way.“

“They don’t get high blood pressure or diabetes or cholesterol or arthritis, so it’s crazily over simplistic to suggest the be all and end all is the category of weight that you are in. But all other things being equal, there is an association with excess body weight and these other problems.”

Finally Prof Finucane said it was important to remember that we still have much to learn about COVID-19 and what it means for people with overweight or obesity.

However, he added that based on early observations people with obesity seem to be at higher risk. Therefore it is important that they adhere to public health advice around social distancing, good cough etiquette and hand washing and to seek help if they feel unwell.

He also advised that people try to eat as healthily as possible and be as physically active as they can reasonably be in the current circumstances, so that their metabolic health is as good as possible, irrespective of their weight.

“Rather than focusing on what the numbers on the weighing scales are saying, they need to look at how healthy they are eating but that applies to everybody not just people with weight problems,” Prof Finucane stated.

We are here for you

The Irish Heart Foundation’s nurse support line is available five days a week. Anyone living with heart disease and stroke who has concerns or questions about the coronavirus can contact the nurse support line on 01 668 5001 or support@irishheart.ie.

The Irish Heart Foundation’s new heart support group is on Facebook. Anyone who lives with heart failure or another heart condition or has a family member living with a heart condition can join here: www.facebook.com/groups/heartsupportnetwork/

The Irish Heart Foundation runs 21 stroke support groups and 5 heart failure groups around the country. All these groups have moved to telephone and online support. For more information, see https://irishheart.ie/get-support/.

The Irish Heart Foundation in conjunction with the HSE National Stroke Programme, has launched a new telephone support service for stroke patients who have recently been discharged from hospital. For more information, see here.