Researchers find fewer than third of patients show much improvement 12 months after discharge
Fewer than one in three patients who have ongoing Covid symptoms after being hospitalised with the disease say they feel fully recovered a year later, according to a study that offers new insights into potential treatments.
As the pandemic has unfolded, a growing body of research has revealed that Covid not only causes health problems in the short-term, but also has long-term effects. Now a study has revealed many of those who had ongoing symptoms after hospitalisation are showing little improvement, with their condition similar at about 12 months after discharge to seven months earlier.
“Only one in three participants felt fully recovered at one year,” said Dr Rachel Evans, one of the co-leads of the post-hospitalisation Covid-19 study – or Phos-Covid – which is led by the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, although the team says missing data means the figure could be as low as two in 10 or as high as six in 10.
The research – which has yet to be peer-reviewed – reveals how the team collected both self-reported and objective measures of health, such as physical performance and organ function, among 2,320 adults about five months after they were discharged from hospital after having had Covid. They then looked at similar measures for 924 participants at about one year after discharge, 807 of whom had attended the previous follow-up.
Between five months and one year after discharge, the proportion of participants reporting feeling recovered remained very similar – at just under 30% at 12 months – as did the prevalence of symptoms including breathlessness, fatigue and pain. Little or no improvement was seen for areas including organ function, physical function and cognitive impairment – or “brain fog” – with about one in 10 participants having a significant degree of the latter 12 months after discharge.
“Unfortunately, we weren’t seeing improvements at one year from where people were at five months post-discharge,” said Evans.
Further work by the team revealed that participants grouped together in one of four “clusters”: very severe symptoms, severe symptoms, mild symptoms and those with severe brain fog and other moderate symptoms. While those in the “mild” group reported about four symptoms on average, those in the very severe group reported about 20.
Evans said the team found minimal or no change in any of the health outcomes between five months and one year across the four clusters, while questionnaires completed by participants rating their health compared with how they retrospectively viewed it before hospitalisation, revealed a significant drop in health-related quality of life at five months – with the impact larger for more severe ongoing symptoms – and then very little change again at one year.
The study cannot prove the cause of the ongoing symptoms, and stressed the need for approaches to improve the mental and physical impairments in patients. However, the team found that being female, obese, able to walk only a very short distance and having raised levels of certain inflammatory proteins in their blood – compared with the mild group – were all linked to having very severe symptoms. Some of the inflammatory proteins were also found to be raised in those with severe brain fog.
Chris Brightling, professor of respiratory medicine at the University of Leicester and chief investigator on the study, said the team is trying to unpick whether autoimmunity may be a driver, adding anti-inflammatory drugs could be tested to see if they aid improvement.
Evans added that weight management and improving walking distance are other areas to explore as possible interventions.
“One of the key messages we are keen to really get through is that none of us think long Covid has one mechanism and one treatment,” said Evans. “We need the groups to define their particular problem, and then target the management accordingly.”