More than half of patients reported not being fully recovered seven months after onset of Covid-19 symptoms in new research. Of these patients, the worst affected were middle-aged, white females with two or more comorbidities, and more severe acute illness.

Two studies were carried out. The first was led by the University of Leicester and followed up more than 1,000 patients who had been admitted to hospital with Covid-19 in the past year. It found that 70% had not fully recovered after an average of five months after leaving hospital.

These patients experienced a range of symptoms, including fatigue, muscle aches, breathlessness and “brain fog” for a prolonged period after contracting the virus.  

These ‘long Covid’ symptoms had a severe impact on the quality of life of these patients. For example, the illness stopped 18% of people returning to work and forced 19% to change their job.

The study found that there was no obvious connection linking how ill people were originally to the severity of their long Covid symptoms. Many patients who had relatively short hospital stays still had ongoing problems.

The researchers found that those who were least likely to make a full recovery were female, white, aged between 40 and 60, had two or more comorbidities and had been on a ventilator.

No obvious connection between disease severity and long Covid symptoms

The research is yet to be peer reviewed, but has been described by England’s chief medical officer, Chris Whitty, as “useful”. He said: “We are in the foothills of our understanding of long-term effects of Covid.

“It is important that we work out what exactly the various elements of what is currently termed long Covid are so we can target actions to prevent and treat people suffering with long-term effects.

“This research provides useful information on the effects of Covid some people are living with months after being hospitalised.”

The second study, which was smaller in terms of scale, was led by Glasgow university. The results found that women under 50 were seven times more likely to be more breathless. They were also twice as likely to report worse fatigue than men of the same age who had coronavirus, up to seven months after hospital treatment.  

Women in this age group were also more likely to have a new disability than men of the same age who had also had the illness. These new difficulties often related to memory, mobility, vision and hearing.

Why are women more likely to experience long Covid symptoms?

The reason why women were less likely to make a quick, full recovery could be explained by a potential biological factor. In many of the most severe long Covid cases, elevated levels of a chemical called CRP (which is associated with inflammation) were found.

Professor Louise Wain, chair in respiratory research at the University of Leicester and co-investigator for the PHOSP-COVID study, said: "It is known that systemic inflammation is associated with poor recovery from illnesses across the disease spectrum.

"We also know that autoimmunity, where the body has an immune response to its own healthy cells and organs, is more common in middle-aged women.

"This may explain why post-COVID syndrome seems to be more prevalent in this group, but further investigation is needed to fully understand the processes."

The patients in the study will be assessed again at 12 months to help inform how the long-term effects of COVID can best be treated.

The researchers of the study say that the results represent a need for a pro-active approach with wide-access to Covid-19 holistic clinical services. By doing so, health professionals can identify ongoing health problems as a result of Covid-19 and provide personalised help and support for those suffering with long-term effects from the illness.