COVID-19 is associated with increased risks of post-viral illness, fatigue, embolism, depression, anxiety and respiratory conditions, according to new research led by Swansea University.
As the pandemic continues, there are growing concerns around the long-term symptoms experienced by people who have had COVID-19. However, there is little research into long-term COVID and its impact on healthcare.
About the study
This study, published in MedRxiv, looked to establish whether testing positive for COVID-19 resulted in increased use of primary and secondary care in the first six months following the test compared to those who had not tested positive.
Robust comparison
This study used propensity matching, a technique that looks to reduce bias and unfairness in research. Using this technique, the study matched people who tested positive for COVID with people with similar characteristics such as gender, age, and local authority area who did not test positive for COVID – creating a robust comparison group.
The study used the Secure Anonymised Information Linkage (SAIL) Databank in Wales, which includes nationwide GP data, hospital in- and out-patient records, and death records collected by the Office of National Statistics (ONS).
The team studied data from over 41,000 individuals living in Wales who tested positive for COVID between 28/02/20 and 26/08/21. Researchers looked at healthcare contact in the 1-4 weeks and 5-24 weeks following a positive COVID-19 test.
Results
Compared to people who tested negative, positive individuals were:
- 212% more likely to die in the first four weeks.
- 28% less likely to die between five and twenty-four weeks if they were tested in the community but, 22% more likely to die if they tested positive in hospital.
- 204% more likely to receive a sick note in the first four weeks if tested in the community.
- 17% less likely to attend a healthcare setting for anxiety or depression in the first four weeks. However, individuals who tested positive in the hospital were 20% more likely to attend for anxiety and depression between five and twenty-four weeks.
- More likely to attend healthcare for post-viral illness (365%), fatigue (65%), and embolism (50%) after 5 weeks if tested in the community.
Despite the strong associations found between testing positive for COVID and healthcare use in the short and long term, the overall number of individuals attending a healthcare setting was very low. However, the study cannot capture the needs of people who have illnesses associated with COVID but did not seek healthcare.
Understanding the long-term effects
Jon Kennedy, the Lead Researcher and Data Analyst at the National Centre for Population Health & Wellbeing Research, said:
“Long COVID is poorly understood. Therefore, research in this area is essential in understanding the consequences of the disease.
Our findings show that a significantly greater proportion of people who had COVID-19 are suffering from long-term illness such as fatigue, post-viral disease, and embolisms, compared to those who were not infected,
Based on our findings, we recommend that people, especially the vulnerable, continue to protect themselves from COVID-19 and the long-term effects of the disease.”
This research was a collaboration between the National Centre for Population Health & Wellbeing Research (Swansea University), Datalab (Nuffield Department of Primary Care Health Science), Bristol Medical School (Bristol University), Institute of Health Informatics (UCL London) and the MRC Social and Public Sciences Unit (University of Glasgow).
The National Centre for Population Health and Wellbeing Research is funded by the Welsh Government through Health and Care Research Wales.