Hundreds of research studies have now investigated long COVID, in which symptoms of COVID-19 and other health issues linger for months after the acute phase of infection has passed. Long COVID can occur in people who have had any type of COVID-19, from mild to severe. Researchers have been categorizing various symptoms of long COVID and have proposed that there are subtypes of the disease. Scientists have also been following long COVID cases to determine how long symptoms might last.
In a new report published in the Journal of the Royal Society of Medicine, scientists have shown that organ damage continued to occur in 59 percent of long COVID patients twelve months after their symptoms started. This was true even for some people who had not experienced severe COVID-19.
This research included 536 long COVID patients, 13 percent of whom had been hospitalized when diagnosed with COVID-19. Patients who had reported poor quality of life, extreme breathlessness, and cognitive dysfunction were the focus of this study.
Out of 536 study participants, 331 (62 percent) had persistent organ dysfunction six months after they'd been initially diagnosed. There was a follow-up with the study volunteers six months later, in which they received an organ MRI scan. This revealed that 29 percent of long COVID patients had trouble with multiple organs, such as reduced function and other symptoms specific to the organ. At the one-year follow-up, there was impairment in a single organ in 59 percent of the study participants.
Symptoms of breathlessness began to go away between six and twelve months, but only for some patients; the individuals reporting breathlessness at six months was 38 percent, and it dropped to 30 percent at one year; cognitive dysfunction decreased from affecting 48 to 38 percent of participants; quality of life disruption was experienced by 57 percent, then 45 percent of patients.
"Several studies confirm persistence of symptoms in individuals with long COVID up to one year. We now add that three in five people with long COVID have impairment in at least one organ, and one in four have impairment in two or more organs, in some cases without symptoms," said study co-author Professor Amitava Banerjee of the UCL Institute of Health.
More research will still be needed to understand the mechanisms underlying the development of long COVID.