A Dutch study released on Saturday reports that one in eight adults who are infected with COVID-19 experience long-term symptoms or what is often known as long COVID.
Long COVID refers to any of more than two dozens symptoms that linger, recur or first appear at least one month after a coronavirus infection. These can affect all parts of the body and may include fatigue, shortness of breath, brain fog and blood clots.
The study, which was published in The Lancet, found that of its 76,422 participants, had persisting COVID-19 symptoms, including “chest pain, difficulties with breathing, pain when breathing, painful muscles, ageusia or anosmia, tingling extremities, lump in throat, feeling hot and cold alternately, heavy arms or legs, and general tiredness.”
The study added that in “12.7 per cent of patients, these symptoms could be attributed to COVID-19, as 381 (21.4 per cent) of 1782 COVID-19-positive participants experienced at least one new or severely increased symptom three to five months post-infection compared to before infection, compared to 8.7 per cent of uninfected people surveyed during the same time period, suggesting one in eight COVID-19 patients (12.7 per cent) in the general population experience long term symptoms due to COVID-19.”
In a statement released Thursday, the lead author, Judith Rosmalen from the University of Groningen in the Netherlands, said the study called the “Persistence of somatic symptoms after COVID-19 in the Netherlands” looks into the symptoms most often associated with long COVID, including breathing problems, fatigue and loss of taste or smell, both before a COVID-19 diagnosis and in people who have not been diagnosed with the virus.
“This method allows us to take pre-existing symptoms and symptoms in non-infected people into account to offer an improved working definition for long COVID and provide a reliable estimate at how likely long COVID-19 is to occur in the general population,” said Rosmalen.
She said there is an “urgent need” for data that can inform the scale and scope of the long-term symptoms experienced by some patients after COVID-19 illness.
“However, most previous research into long COVID has not looked at the frequency of these symptoms in people who haven’t been diagnosed with COVID-19 or looked at individual patients’ symptoms before the diagnosis of COVID-19,” Rosmalen added.
Researchers identify core symptoms of long COVID-19
According to the press release, in this study, researchers collected data by asking participants to regularly fill out digital questionnaires on 23 symptoms commonly associated with long COVID.
The questionnaire was sent out 24 times to the same individuals between March 2020 and August 2021.
“Most of the data were collected before the COVID-19 vaccine rollout in The Netherlands so the number of vaccinated participants was too small to analyze in this study,” the press release stated.
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Researchers said by looking at the symptoms of individuals both before and after a COVID-19 infection they were able to identify core symptoms of long COVID-19.
These core symptoms are chest pain, difficulties breathing, pain when breathing, painful muscles, loss of taste and smell, tingling extremities, lump in throat, feeling hot and cold, heavy arms and/or legs, and general tiredness.
“The severity of these symptoms plateaued at three months after infection with no further decline,” the release said.
“Other symptoms that did not significantly increase three to five months after a COVID-19 diagnosis included headache, itchy eyes, dizziness, back pain and nausea,” it added.
PhD candidate and first author of the study, Aranka Ballering, said that “these core symptoms have major implications for future research, as these symptoms can be used to distinguish between post-COVID-19 condition and non-COVID-19-related symptoms.”
Ballering said that as a result of the study she and her teammates were able to identify symptoms that stem from people experiencing stress caused by the pandemic, which are more mental than physical.
“Post-COVID-19 condition, otherwise known as long COVID, is an urgent problem with a mounting human toll. Understanding the core symptoms and the prevalence of post-COVID-19 in the general population represents a major step forward for our ability to design studies that can ultimately inform successful healthcare responses to the long-term symptoms of COVID-19,” she said.
-With files from Reuters