Almost half of people that caught Covid-19 are still suffering from symptoms up to 18 months after being infected, a study has found.
The first results of a largescale study into the effects of long Covid carried out by Scottish researchers have been published.
It found that one in 20 people have not recovered from the virus and 42% of people infected reported feeling only partially better within six to 18 months.
The Long-CISS (Covid in Scotland study), led by the University of Glasgow, is one of the largest of its kind to date and was set up in May 2021 in order to understand the long-term impact of Covid-19.
Public Health Scotland, the NHS in Scotland, and the Universities of Aberdeen and Edinburgh also collaborated on the research which was funded by the Scottish Government Chief Scientist Office.
The first results reveal that one in 20 people who took part in the research had not recovered from having Covid-19 at their most recent follow up – between six and 18 months following infection.
The study found that the impact for people with long-Covid was wide-reaching, with a range of symptoms impacting their daily life and reducing the quality of their life.
Research revealed that long-Covid was more likely in cases of severe infection requiring hospitalisation.
The most common symptoms of long-Covid included breathlessness, chest pain, palpitations, and confusion, or ‘brain fog’.
Researchers also found that long-Covid was more common in people who were older, female and from deprived communities.
Those with pre-existing physical and mental health problems, such as respiratory disease and depression, were also more likely to suffer symptoms of the virus for a longer period.
The study found that whilst recovery status remained constant over the follow-up period for most participants, 13% of people reported improvement over time and 11% reported some deterioration.
However, the first results, published in Nature Communications, revealed that those with asymptomatic infection had no long-term impact; and people who had been vaccinated prior to infection with COVID-19 appeared to have protection from some long-term symptoms.
The study used a Scottish population cohort of 33,281 laboratory-confirmed coronavirus infections, matched with 62,957 who has never been infected.
Both groups were followed-up with six, 12 and 18-month questionnaires with researchers able to link to hospitalisation and death records.
Using NHS health data records, all Scottish adults who had a positive Covid test, as well a sample of people who tested negative for the disease, were sent an SMS message inviting them to take part in the CISS study.
Individuals were then asked to answer questions online about their health, both before and after COVID-19, to determine whether the virus has had any lasting effects on their lives.
Professor Jill Pell, professor of public health at the University of Glasgow, who leads the study, said: “While most people recover quickly and completely after infection with COVID-19, some people develop a wide variety of long-term problems. Therefore, understanding long-COVID is essential to inform health and social care support.
“Our study is important because it adds to our understanding of long-COVID in the general population, not just in those people who need to be admitted to hospital with COVID-19. By comparing symptoms with those uninfected, we were able to distinguish between health problems that are due to COVID-19 and health problems that would have happened anyway.”
Dr Andrew McAuley, consultant healthcare scientist at Public Health Scotland, said: “This study provides novel and important evidence on long-COVID in Scotland. We know that being fully vaccinated against COVID-19 can reduce the likelihood of developing long-COVID and therefore we encourage those who are eligible for the COVID vaccine to take the opportunity to enhance their protection by getting vaccinated.”
The study, ‘Outcomes among confirmed cases and a matched comparison group in the Long-COVID in Scotland Study’ is published in Nature Communications.
The study is funded by the Chief Scientist Office and Public Health Scotland.