In the largest and longest follow-up study conducted to date investigating the lingering effects of COVID-19, researchers have found more than two-thirds of hospitalized patients report at least one ongoing symptom six months after contracting the disease.
Across much of 2020, doctors noted they were seeing some COVID-19 patients display enduring symptoms beyond the few weeks of acute disease. This condition is informally known as long COVID.
As 2020 progressed, a number of studies began to appear exploring the phenomenon of long COVID. But considering how fundamentally new this disease was, there was no clinical data to offer insights into how many people could experience persistent symptoms.
A new study, published recently in The Lancet, presents the largest and longest insight into long COVID published to date. The study encompasses 1,733 hospitalized COVID-19 patients from Wuhan, China. Each patient was followed for at least six months.
"Because COVID-19 is such a new disease, we are only beginning to understand some of its long-term effects on patients' health,” says Bin Cao, corresponding author on the new study. “Our analysis indicates that most patients continue to live with at least some of the effects of the virus after leaving hospital, and highlights a need for post-discharge care, particularly for those who experience severe infections.”
A striking 76 percent of all patients reported at least one continuing symptom six months later. The most common lasting problem was fatigue or muscle weakness, reported by 63 percent of all patients. Around a quarter of the cohort also reported sleep difficulties and anxiety or depression.
A smaller subset of the cohort completed comprehensive pulmonary testing and more than half displayed persistent chest imaging abnormalities. The degree of ongoing lung damage six months later correlated with the severity of the disease during the patients’ acute phase of hospitalization.
“Our work also underscores the importance of conducting longer follow-up studies in larger populations in order to understand the full spectrum of effects that COVID-19 can have on people,” says Cao.
A number of surveillance studies are ongoing, tracking the long-term effects of COVID-19. This particular new analysis is limited to hospitalized patients so it doesn’t offer any insight into how the disease can linger in milder cases.
As more time passes, the long-term impact of COVID-19 will hopefully become much clearer. Frances Williams, from King’s College London, suggests it will take time to separate the direct impact of the virus from the broader impact of the pandemic. But either way, Williams adds, the public health fall-out from COVID-19 will persist for years, if not decades.
“With so much having happened over the last year, we will need to tease apart which impacts stem from the virus itself versus which might be the consequence of the massive social disruption wrought by this pandemic,” writes Williams in a recent piece for The Conversation. “What is clear, however, is that long-term symptoms after COVID-19 are common, and that research into the causes and treatments of long COVID will likely be needed long after the outbreak itself has subsided.”
The new study was published in The Lancet.
Source: The Lancet