One in eight adult covid patients, 12.7 percent, still have long-term, new complaints after three months that can be attributed to the infection with the coronavirus, also known as lung covid or post-covid syndrome. A Dutch study now accurately unravels for the first time which long-term complaints were already present in those patients before SARS-CoV-2 struck, and which are also present in people who did not contract Covid-19.
Previous estimates of the percentage of Covid patients who have long-term complaints varied widely. Often people register themselves in those studies, and are only asked whether there are complaints, not whether they are new or greatly aggravated. The new study does, making it the most reliable estimate to date. The medical-scientific journal The Lancet released the findings Friday.
Aggravated symptom
Of all Covid patients, 21.4 percent had at least one new or significantly worsened symptom three to five months after infection. In people who were not infected, this was 8.7 percent – those complaints were caused, for example, by another pathogen or by stress from the pandemic. In 12.7 percent of Covid patients, the long-term complaints can be regarded as post-covid syndrome (also known as PASC, Post-Acute Sequelae or SARS-CoV-2 Infection).
In particular, loss of smell or taste, breathing problems, chest pain, fatigue and muscle aches were significantly more reported by this group. Heavy arms and legs and hot and cold chills were also reported more often after three to five months than before, or than uninfected people. Complaints such as headache, dizziness and back pain were just as common after three months as before the infection and in the control group.
The research was done at a time when the original virus and the alpha variant were circulating, and virtually no one had yet been vaccinated. The results are therefore not necessarily valid for the current situation. The risk of lung covid now appears to be somewhat lower. From the scientific studies that have been done to date, the picture emerges that people who have been vaccinated are less likely to have long-term complaints from a corona infection than unvaccinated people. An analysis by the British Bureau of Statistics even suggests that vaccination can help to alleviate long-term complaints in people who already have long covid. The risk of lung covid also appears to be lower after infection with Omikron compared to previous variants.
Long walking
The study is based on data collected in Lifelines, a long-term study that has followed 167,000 people of all ages from the three northern Dutch provinces since 2006. They regularly fill in questionnaires about their lifestyle and come to the hospital every five years for all kinds of tests, such as a blood pressure measurement, a heart film, cognitive tests and a lung function test.
“When the pandemic started, we quickly switched and emailed all adults a questionnaire about corona from March 31, 2020,” says study leader Judith Rosmalen, professor of psychosomatics at UMC Groningen. More than 76,000 people took part – 61 percent were women, the average age 54 years, almost everyone white. “We initially sent a questionnaire every week, then every two weeks and now monthly.” The lists include 12 symptoms already surveyed in Lifelines, including headache, breathing problems, back pain, chest pain, fatigue, dizziness, and tingling in the hands or feet, as well as 11 covid symptoms known at the start of the pandemic, such as a runny nose, sore throat, loss of smell or taste.
Until August 2, 2021, 5.5 percent of the participants had Covid-19, determined by a PCR test or by a doctor during the period when little was still being tested. In each of them, the researchers looked for data from two age- and gender-matched individuals who did not have Covid-19.
Recognition
The findings will strengthen people with long-term complaints after Covid-19 in their fight for recognition of their complaints. These are sometimes dismissed as psychological, or caused by stress. “All complaints can have different causes, including stress. But we show that people who are not infected, but who experienced the same stress of the pandemic, have significantly fewer complaints,” says Rosmalen. “Biomedical factors play a role in all long-term complaints and other factors, such as psychological ones, always play a role. But just because we don’t know the physical yet, doesn’t mean we’re dealing with a psychological problem here. It’s not either-or, it’s both-and.” Scientists have to look for the physical mechanisms, says Rosmalen, “and at the same time they have to look at what those complaints mean for people, and how we can help them to work again and how can we support them with all the consequences of those complaints.”
A disadvantage of the rapid action at the start of the pandemic is that ‘long covid’ was not yet known at all. Characteristic post-covid symptoms such as the aggravated complaints after exercise and cognitive problems such as ‘brain fog’ were therefore not asked in this study. “We will later, but we don’t have enough data on that yet,” says Rosmalen.
Not all long-term complaints in the reported 12.7 percent of patients are so limiting that people can no longer function, Rosmalen emphasizes. “But even if only a quarter of them were seriously disabled, about 3 percent, that would still be a very large group, because a lot of people in the Netherlands have had Covid-19. These people need to be properly helped.”
Tilt table test
In Groningen, the researchers will continue to follow the group of people in the study for a long time to come. Rosmalen: “We take extra measurements, such as an exercise test and a tilt table test to look at the function of the heart and blood vessels and the autonomic nervous system. We are looking for indications of organ damage and of inflammatory processes.”
As miserable as the prolonged symptoms after Covid-19 are for some people, it is scientifically valuable. “There have always been people who developed long-lasting symptoms after an infection, such as after Q fever, mononucleosis, sometimes with ME-CFS. That was difficult to investigate,” says Rosmalen. “We are now in a unique situation in which a very large group of people have received a completely new virus that we all had no defense against. For the first time, this provides the opportunity to examine the long-term complaints after such an infection in detail and from the outset. We may also learn more about those long-term complaints after other infections.”
Also read: Long trapped by the coronavirus: a riddle with no quick solution