Understanding the impact of long COVID to improve future treatment


A study into long COVID has highlighted the need for greater research, diagnostic procedures, and pandemic preparedness moving forward.

For the foreseeable future, the coronavirus is something we must learn to live with. Yet, while for many this means adhering to varying safety measures that are in place, for others it is learning to live with the symptoms of the virus for weeks or even months following the initial onset of infection. ‘Long COVID’ or ‘post-COVID-19 syndrome’ can manifest itself in multiple ways and affect those who experienced both mild and severe symptoms. According to a recent review by the National Institute for Health Research Centre for Engagement and Dissemination (NIHR), 20% to 30% of people who were not hospitalised experienced long-term COVID symptoms and at least 10% of those have still not fully recovered three months later.

The range of symptoms incurred and diagnostic ambiguity surrounding long COVID presents many challenges for healthcare providers who do not have the necessary tools or knowledge to recommend the best treatment for the patient. To find out more about the impact of long COVID, Health Europa Quarterly (HEQ) spoke to Dr Amitava Banerjee who is an Associate Professor in Clinical Data Science and Honorary Consultant Cardiologist at University College London. Along with a team of researchers, he conducted a study to understand the long-term effects of COVID-19 by comparing the rate of multiorgan dysfunction between individuals discharged from hospital after contracting the disease and a control group from the general population.

What are the most prevalent symptoms of long COVID?

There is a really wide range of symptoms that people might present within various studies, including research studies and studies from actual clinics. There are cardiorespiratory symptoms, such as breathlessness, a persistent cough and chest pain. There are also what you might call constitutional symptoms which include tiredness, lack of energy, low mood and in some cases, a loss of appetite. Some people have also reported various neurological symptoms including brain fog, insomnia, or dizziness.

The challenge now is trying to clarify which symptoms relate to which risk of impairment, in terms of an organ or abnormalities on blood tests or scans and then trying to look at clusters or subtypes of symptoms. A colleague of mine who runs a post-COVID service at the University College London calls it building the plane while it is flying. It is a new disease that we are still trying to define and therefore it is difficult to design a care pathway for that not-fully-defined disease. Then of course, this is all against the backdrop of a health system that is already stretched, not just for COVID, but the backlog of non-COVID services, too.

We have several studies going on around the world that will shed light on this disease, but I think everybody feels that there is likely to be a range of different symptoms recorded. It is not simply a one-on-one condition. For example, at the University College London, we have looked at people who have been hospitalised and those that were not hospitalised after contracting COVID and there seems to be a difference in the symptoms both groups presented.

What external factors – such as age, environment, and previous conditions – need to be considered in a study of this nature?

With mortality or hospital admission acutely from COVID-19 it has been clear since Wuhan that age and underlying conditions are the main drivers. With long COVID in the post hospitalised group, there is a signal that underlying conditions are an important factor but actually, the thing with long- COVID is, the severity of the initial disease is not so relevant and the age groups that are affected include much younger people. In terms of other factors, there is not a particular underlying condition that we have drawn up. There have been signals from different studies about asthma being a contributing factor, but that is not a hard and fast finding to my knowledge. The other thing is that some of the patterns that we have seen with regards to ethnicity and those that were more at risk of hospital admission and mortality in the first two waves are not necessarily the same for long COVID. We have more questions than answers at the moment.

© iStock/gorodenkoff
People have reported a wide range of symptoms for long COVID, from extreme tiredness to high temperature, loss of appetite and difficulty sleeping.

Are there links or similarities between post-COVID syndrome and post-intensive care syndrome?

There is an area of research and clinical practice which is trying to define what is going on at the moment with regard to this. Post intensive-care syndrome means anybody who is still experiencing health problems after having been treated in an intensive care unit. They can experience long-term psychological, neurological, and respiratory symptoms, similar to those people who were hospitalised with COVID.

Some people think of COVID as one of the main conditions that lead people to develop a post-intensive care type syndrome. There are other comparisons that are often made between post-COVID syndrome and other post-viral syndromes, such as chronic-fatigue syndrome (ME), as well as cardiorespiratory symptoms where people may feel dizzy and faint. There is also a syndrome called postural tachycardia syndrome (PoTS) that has been likened to long COVID. It is not easy to distinguish between post-COVID syndrome and post intensive-care syndrome, we need to compare different types of COVID and the patients who go on to develop post-COVID syndrome. We also need to compare with health and controls and those other diseases. The most important thing at the moment is that we do not have an effective treatment for post-COVID syndrome.

If you look around the world, the NHS is probably ahead in terms of trying to set up dedicated services for post-COVID syndrome, but those services are really limited due to the diagnostic uncertainty and the lack of proven treatments that are available. We think that rehabilitation strategies work, but we do not have trials to show that yet. I think the most sensible thing we have learned is that the best way to avoid developing post-COVID syndrome is to avoid COVID in the first place. Even now, with the easing and delaying of restrictions, there is no dialogue or mention from the Prime Minister regarding long- COVID which undoubtedly has a massive impact on society. The reason New Zealand does not have to do any research and devote resources to this is because they had an infection suppression strategy. Whereas any country that has let the infection run amok is faced with this issue, so the best way to avoid it going forward, whether it is a new or old variant, is to keep the infection rate down which seems obvious, but I think it is worth saying every time we talk about it.

Is there a possibility of additional longer-term issues associated with long COVID which have yet to be identified?

In the post-hospitalised group, we did the first study in the world using data from the Office for National Statistics (ONS) and among the 45,000 people hospitalised with COVID-19 and later discharged, there was still a high-rate of mortality. We found that after four or five months of being discharged, there were one in 10 to one in 12 deaths. Our study showed that 20% of people were readmitted and there were new chronic diseases – cardiovascular, kidney, liver, respiratory – all in the sub 10% range, but sufficient that there might be long-term conditions that we need to look for.

© iStock/solarseven
With long COVID, the severity of the initial disease is not so relevant and the age group that is affected includes much younger people.

Is there a need for additional or more targeted research into post-COVID syndrome?

The UK has now had two rounds of dedicated funding calls, but I would like to see it as part of the policy research clinical strategy for COVID in general. Beyond research, this is clearly part of pandemic preparedness. When we consider SARS or Ebola, we have not really thought about preparing our services for longer-term conditions. Thinking about non-COVID or non-infectious disease conditions – because post-COVID syndrome does not behave like your average infectious disease – you need multidisciplinary care, you need physiotherapists, occupational therapists and potentially psychologists. There is much more chronic disease management required. That is part of emergency preparedness beyond just modelling cases of deaths. Going forward that has to be part of our way of doing things.

Dr Amitava Banerjee
Associate Professor in Clinical Data Science and Honorary Consultant Cardiologist
Institute of Health Informatics, University College London

This article is from issue 18 of Health Europa. Click here to get your free subscription today.

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