These Are The Risk Factors For Long Covid

If you’re a woman or you experienced multiple Covid-19 symptoms in the first week of infection, you’re more likely to experience long Covid, according to new research.

New analysis by researchers at King’s College London, using data from the Covid Symptom Study app, shows that one in 20 people with Covid-19 are likely to suffer symptoms for eight weeks or more – so-called long Covid.

This potentially adds up to many hundreds of thousands of people in the UK and millions worldwide.

Now, the researchers have identified the long Covid risk factors, providing some insight into who is most likely to be affected. 

Having more than five different symptoms in the first week of infection was one of the key risk factors. Headache, fatigue, loss of smell, fever and a persistent cough are the five most common symptoms of Covid-19 people have reported to the app. Other possible symptoms include a rash, diarrhoea and vomiting.  

Women under the age of 50 were 50% more likely to suffer from long covid than men (14.5% compared with 9.5%). However, this gender difference wasn’t seen in the older age categories. 

Overall, the chance of being impacted by long covid increased with age. Long covid was found to affect around 10% of 18-49 year olds who become unwell with coronavirus, rising to 22% of over 70s.

Weight also plays a role, with people developing long covid having a slightly higher average BMI than those with short covid. 

The study focused on data from 4,182 Covid Symptom Study app users who had been consistently logging their health and tested positive for Covid-19 through swab PCR testing.

The team found that while most people with Covid-19 reported being back to normal in 11 days or less, around one in seven (13.3%) had Covid-19 symptoms lasting for at least four weeks, with around one in 20 (4.5%) staying ill for eight weeks and one in 50 (2.3%) suffering for longer than 12 weeks.

Dr Claire Steves, clinical academic and senior author from King’s, thanked everyone who’s used the app so far and urged for more people to take part.  

Professor Tim Spector, Covid Symptom Study lead and professor of Genetic Epidemiology from King’s, added: “Covid-19 is a mild illness for many, but for one in 50 symptoms can persist for longer than 12 weeks.

“So it’s important that, as well as worrying about excess deaths, we also need to consider those who will be affected by long Covid if we don’t get the pandemic under control soon.”