What after-effects one year after hospitalisation?

The COVID-19 pandemic remains a major problem for public health. It has infected more than 200 million people and there have been more than 4,3 million deaths. Post SARS-CoV-2 infection after-effects have already been reported, and this is becoming a matter for concern in view of the large number of cases. Until recently, 2 studies had been published involving only 120 patients who had been infected by the virus and were monitored over 12 months, but they reported only respiratory problems. In general, the long-term consequences of COVID-19 are little known in patients having been hospitalised. However, Chinese researchers have just reported on after-effects in patients 6 months and 12 months after hospitalisation.  

The researchers studied a cohort of 1 276 infected patients who were admitted to Wuhan hospital between the 7^th of January and the 29^th of May 2020, with an average age of 59. After 6 and 12 months, the patients filled out a questionnaire on their symptoms and their quality of life. They also had a medical examination, a test of their walking, and laboratory analyses. In addition, their work activity was logged during the 12 month visit.  

What were the results? The proportion of patients experiencing at least one after-effect reduces between 6 and 12 months, from 68 to 49%, no matter how severe the illness. Some of the most widely reported after-effects include muscle weakness and fatigue. These symptoms, like others (difficulties in sleeping, hair loss, problems with taste and smell) disappear, in the majority of cases, in between 6 and 12 months.

However, certain symptoms affect more people after 12 months than after 6 months, such as anxiety or depression (26% at 12 months as opposed to 23% at 6 months). The researchers also noted that respiratory difficulties continue in certain patients, but principally in those who had been critically ill.

Before COVID-19, 53% of these individuals had retired, and 38% were in full-time or part-time employment. After 12 months, 88% of them had restarted their former jobs. 12% of people no longer worked as before, and for 32% in this group, it was because they felt they no longer had the physical capacity.

Overall, what was the quality of life of these patients? When the researchers compared them to other people, in a control group of 3 383 people who had been hospitalised for other reasons, it appeared that the declared quality of life for COVID-19 patients was less good.

But are these results systematic? In reality, they vary according to the type of treatment received. The scientists noted that treatment by corticosteroids during the acute phase of COVID-19 increased the risk of fatigue and muscular weakness in the following months. However, treatment by therapeutic antibodies reduced this risk. These 2 treatments were not, however, linked to an increased risk of anxiety or depression, unlike the risk factor of age.  

This study is the largest carried out on after-effects suffered by patients who have been infected by SARS-CoV-2 and hospitalised. In general, patients recovered well and were able to take up their former work. However, a certain number of after-effects did persist and individuals who have been infected are generally in less good health than people who have not had COVID-19. It will be necessary to continue to monitor these patients over an extended period to try and understand the long-term pathogenesis of this virus.