While the severity of Covid-19 infection can vary greatly, new research suggests it is not an indicator of who is most likely to suffer from long-term symptoms.
To date, little has been known about long-term lung health following infection with SARS-CoV-2, the virus that causes Covid-19.
But now, researchers from Trinity College Dublin have presented a new study to assess lung function and respiratory symptoms in patients across the full range of initial Covid-19 severity.
The team found that while symptoms such as fatigue, ill-health and breathlessness were all common following Covid-19, ongoing symptoms appeared to be unrelated to the severity of the initial infection.
The study, detailed in a peer-reviewed paper published today (8 January) in the Annals of the American Thoracic Society, looked at a number of measures for recovery for 153 patients who were followed in an outpatient clinic for a median of 75 days after their Covid-19 diagnoses.
The research found that 62pc of patients felt they had not returned to full health, while 47pc were classified as having fatigue. However, the results suggested that Covid-19 does not cause significant fibrosis, with lung scarring seen on CT scans of only 4pc of participants.
While the findings show significant symptom burden, there is a relatively low rate of abnormal objective findings.
These results add to previously published work which suggests that there is no simple diagnostic test for so-called long-haul symptoms, and that the diagnosis is based on patient’s own reported symptoms.
Dr Liam Townsend, research fellow at Trinity College Dublin who led the research, said the team was surprised by the findings. “We expected a greater number of abnormal chest x-rays. We also expected the measures of ongoing ill-health and abnormal findings to be related to severity of initial infection, which was not the case,” he said.
“Our findings have implications for clinical care, in that they demonstrate the importance of following up all patients who were diagnosed with Covid-19, irrespective of severity of initial infection. It is not possible to predict who will have ongoing symptoms.”