Acknowledgement is important

For the study, we investigated so-called routine care data: existing anonymous data from the electronic patient files of GPs and hospitals. Each year, the Netherlands Institute for Health Services Research (Nivel) collects these data from 10 percent of the population. We also issued questionnaires to people who had experienced a COVID-19 infection, and we conducted interviews with patients and GPs. We therefore chose a mixed methods approach. We posed questions such as: how often does Long COVID occur, what are the symptoms, what are the risk factors, which care have people received, and how did they experience that care?

We formulated several definitions. For example, a strict definition according to which somebody must have visited the GP with several symptoms within 3 months after the COVID-19 infection. And a flexible definition according to which a single persistent complaint is enough to satisfy the definition of Long COVID. If you play around with such a definition, you gain a better understanding of the extent of the problem. For the three data sources – electronic patient files, questionnaires and interviews – we used a different definition. This allows us to see what the influence is on the method.

Our study revealed, for example, that about 15 to 33 percent of people who experienced a COVID-19 infection suffered from persistent symptoms. Interestingly, this mainly concerns middle-aged women, independent of the definition used and the data source. We also know which questions they went to the GP with. These are often psychological complaints such as despondency and anxiety, but also abdominal pain and breathing problems. Conversely, tiredness, muscle ache and brain fog (symptoms associated with the ability to think) were mainly reported in the questionnaire. Therefore, people do not go to the GP with these symptoms or the GP does not code these as such.

We obtained yet other data from the interviews. There, patients mainly reported their experiences with care providers. Some care providers still consider Long COVID to be a questionable diagnosis, and they share this opinion as well. In such cases, patients do not feel that they are taken seriously. That is very difficult for them and it does not have a positive effect on the recovery process. Acknowledgement is important. Patients also experienced little after-care and supervision in the entire trajectory. This is despite the fact that they can benefit a lot from online contact groups where they can share their experiences with other patients. It helps them to find a way to deal with the illness.

A number of research results are already known. For example, in the data from interviews, we see a division among patients with Long COVID. There is a group with an extensive medical history and a group that, on the contrary, always used to be very fit. GPs state that these two groups deal differently with Long COVID and may therefore need a different approach. They think the first group will benefit from a slightly more active lifestyle and a focus on the underlying problems in particular. According to the GPs, the other group needs to slow down. This group would benefit from rest and planning activities better.

The outcomes of our research says something about Long COVID after an infection with the original virus. But what do the data say about persistent symptoms after an infection with virus variants such as the Omicron variant? We would like to investigate that because some people still develop Long COVID. It is not known how large that group is. That is what we need to investigate and the data for that are available. Patients still have many questions about Long COVID. Therefore funding is important.

Corona has caught us by surprise. Researchers therefore feel under pressure to do everything quickly. For example, the definition of Long COVID had to be produced within six months. I used to do research into dementia. There it took decades to come up with a definition that is usable for the clinical field. Politicians and policymakers sometimes underestimate how complex things are. And healthcare insurers make the same mistake. Some of them already reimburse the costs for Long COVID treatment, whereas it is still uncertain which therapy works and for whom. Some insurers ask us to swiftly provide results. I understand that they want to be able to help their patients quickly. However, now they are trying to achieve things a bit too fast.

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