Long coronavirus disease 2019 (COVID-19) is a term that is used to describe the persistence of certain symptoms for more than four weeks after patients have recovered from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
Study: Impact of long-COVID on health-related quality of life in Japanese COVID-19 patients. Image Credit: fizkes / Shutterstock.com
This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources
What is long COVID?
To date, over 4.8 million around the world have died as a result of COVID-19. Furthermore, over 233 million individuals have been infected with SARS-CoV-2, of which an estimated 80% of them, according to some studies, have developed one or more symptoms reflecting long-COVID.
Long COVID symptoms can include pain, general fatigue, “brain fog,” trouble sleeping, headaches, shortness of breath, fever, chronic cough, depression, cognitive and mental health disorder, and anxiety. According to the National Institute for Health and Care Excellence (NICE) in the United Kingdom, long COVID encompasses ongoing symptomatic COVID-19 from four to 12 weeks post-infection, as well as post-COVID-19 syndrome extending beyond 12 weeks post-infection.
Since there remains a lack of available and effective treatments for long COVID, these symptoms can affect work and interfere with daily tasks, resulting in a poor quality of life. Long COVID is also further complicated by the fact that this condition can vary significantly between individuals in terms of its duration and symptomology. In addition to a lack of medications available to treat long COVID, a quantitative assessment of the disease burden by long COVID is also unavailable.
To obtain empirical information on the health-related quality of life due to long COVID, researchers recently conducted a survey-based study and assessed the impact of long COVID on the health-related quality of life in Japanese COVID-19 patients.
About the study
In the current study, which is published on the preprint server medRxiv*, the researchers conducted a cross-sectional self-report questionnaire survey of 530 eligible patients who had recovered from acute COVID-19 in April 2021.
These patients were recruited from the outpatient service of the Disease Control and Prevention Center (DCC) in the National Center for Global Health and Medicine (NCGM) in Tokyo, Japan, where they had obtained pre-donation screening tests for COVID-19 convalescent plasmapheresis. Of the eligible patients, 457 participants were included in the current analysis.
The study showed a lower value on a Visual Analogue Scale (VAS) and the EQ-5D-3L for those participants who reported any of the symptoms of long COVID than those reporting no symptoms. VAS is a psychometric response scale that is used as a measurement instrument for subjective characteristics or attitudes that cannot be measured directly.
The EQ-5D-3L comprises five dimensions, of which include mobility, self-care, usual activities, pain/discomfort, depression/anxiety. Each question had three possible responses of no problems, some problems, and extreme problems.
Study findings
Upon comparison of the health-related quality of life scores estimated by the EQ-5D-3L questionnaire between these participants with no symptoms (n=349) and those suffering from long COVID (n=108), the study found a substantial disease burden caused by COVID-19.
Notably, the number of females appeared to be more afflicted as observed in the ‘any symptom’ group, as compared to the no symptoms group. Apart from this, there was no overall difference between the groups in terms of their age and medical history. However, the values were lower in the ‘any symptoms’ group than the no symptom group.
Further, the researchers tabulated the characteristics of “long COVID” symptoms in the paper. In this study, 44% of the participants reported at least one symptom after four weeks have passed since their COVID-19 symptom onset. The most common symptom of long COVID was reported to be ‘general fatigue,’ which was followed by ‘alopecia’ (hair loss).
Due to the varying duration of long COVID, the researchers explained that the quality of life lost attributed to long COVID is far greater than influenza-like illnesses (ILIs). In a previous study in Japan, the quality of life of long COVID patients was higher than that of the acute phase of ILIs.
Based on the results from this study, the researchers recommend effective preventative countermeasures for COVID-19, as the role of the COVID-19 vaccines in long-COVID has not yet been demonstrated.
Some of the limitations of the current study include possible recall biases, a small study cohort, and selection biases. Thus, the researchers call for studies focusing on the frequency and severity of long COVID symptoms following infection with the new SARS-CoV-2 variants, as well as those evaluating the influence of vaccination on long-COVID.
This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources
Journal references:
- Preliminary scientific report.
Tsuzuki, S/. Miyazato, Y., Terada, M., et al. (2021). Impact of long-COVID on health-related quality of life in Japanese COVID-19 patients. medRxiv. doi:10.1101/2021.09.27.21264225. https://doi.org/10.1101/2021.09.27.21264225.
- Peer reviewed and published scientific report.
Tsuzuki, Shinya, Yusuke Miyazato, Mari Terada, Shinichiro Morioka, Norio Ohmagari, and Philippe Beutels. 2022. “Impact of Long-COVID on Health-Related Quality of Life in Japanese COVID-19 Patients.” Health and Quality of Life Outcomes 20 (1). https://doi.org/10.1186/s12955-022-02033-6. https://hqlo.biomedcentral.com/articles/10.1186/s12955-022-02033-6.
Article Revisions
- Apr 29 2023 - The preprint preliminary research paper that this article was based upon was accepted for publication in a peer-reviewed Scientific Journal. This article was edited accordingly to include a link to the final peer-reviewed paper, now shown in the sources section.