The risks of long COVID-19 have been “distorted” due to a flawed body of research, according to experts.
Researchers are pointing to overly broad definitions and a lack of comparison groups, among other factors in studies looking at the incidence, prevalence and control of long COVID for the distortion.
The paper, published Monday in BMJ Evidence-Based Medicine, looked at the working definitions of the condition provided by multiple global health organizations, including the Centers for Disease Control and Prevention, the World Health Organization and the UK National Institute for Health.
None of the definitions required a “casual link” between the virus and a range of symptoms.
The “flaws” have led to consequences such as increased public anxiety, misdiagnoses, increased healthcare spending and a “diversion of funds” from those who are actually suffering from long-term effects of COVID-19, researchers suggest.
“Ultimately, biomedicine must seek to aid all people who are suffering. In order to do so, the best scientific methods and analysis must be applied. Inappropriate definitions and flawed methods do not serve those whom medicine seeks to help,” they study authors wrote in the paper.
Some of the repercussions of being infected with COVID-19 include shortness of breath following pneumonia and post-ICU syndrome, an array of health conditions that are present while in intensive care and persist after discharge — but experts pointed out that these symptoms are very commonly associated with many upper respiratory viruses.
Though it was recently reported that symptoms of the new COVID-19 variant are noticeably weaker than previous waves, and a long-term study of COVID symptoms based in the UK, a sore throat was connected to the illness significantly more often following the Omicron variant of 2021.
However, the researchers argue that the umbrella term “long COVID” should be replaced by different terms for the specific long-term effects.
During the early days of the pandemic when testing wasn’t as widely available, studies mostly included a non-representative sample of patients who tested positive — including those with mild or no symptoms.
This potentially limited the generalization of the findings in these studies due to sampling bias — when certain members of a population are more likely to be included in a study sample than others.
Researchers said that control groups should be included in studies for long COVID, and they should also be “properly matched” to cases based on factors such as age, sex, geography, socioeconomic status and, underlying health and health behaviors — aspects that aren’t typically considered.
“Our analysis indicates that, in addition to including appropriately matched controls, there is a need for better case definitions and more stringent [‘long COVID’] criteria, which should include continuous symptoms after confirmed SARS-CoV-2 infection and take into consideration baseline characteristics, including physical and mental health, which may contribute to an individual’s post COVID experience,” the researchers wrote.
“Improving standards of evidence generation is the ideal method to take long COVID seriously, improve outcomes, and avoid the risks of misdiagnosis and inappropriate treatment,” they added.