Researchers found that more than three-quarters of a cohort of COVID-19 patients still had at least one symptom 6 months after they were discharged from the hospital.
In their study, the researchers found that 76% of COVID-19 patients from a hospital in Wuhan, China, were still not symptom-free at a 6-month follow-up.
The research, which appears in the journal The Lancet, identifies the most common symptoms that the study participants continued to experience.
It also highlights the possible effects of COVID-19 on the participants’ cardiopulmonary health and identifies potential risk factors associated with the long-term effects of COVID-19.
It can range considerably in severity, with some people not noticing that they have the disease and others requiring hospital admission and mechanical ventilation. To date, data show that COVID-19 is responsible for more than 1.9 million deaths.
While the immediate symptoms and disease progression of COVID-19 have been well-documented, the longer term effects of COVID-19 have received less attention.
Dubbed “long COVID,” symptoms that people frequently report experiencing include fatigue, coughing, muscle aches, chest pain, heart palpitations, and rashes.
The researchers behind the present article wanted to get a better understanding of just how prevalent these symptoms are and the associated risk factors that make a person more likely to experience them months after discharge.
With these aims in mind, the researchers conducted a study involving 1,733 patients who had been discharged from a hospital in Wuhan, China, between January 7 and May 29, 2020, after receiving a COVID-19 diagnosis.
The participants had a follow-up appointment an average of 186 days after their discharge. During the appointment, each individual had a face-to-face interview with a doctor to determine what symptoms they were still experiencing. They also underwent laboratory tests, a physical examination, and a 6-minute walking test.
In addition, a subset of 349 participants completed a lung function test, and 94 individuals who had received antibody tests when their infection was most severe had a follow-up antibody test.
The researchers found that 76% of the participants were still experiencing at least one symptom of COVID-19 at their follow-up appointment.
The most common symptom was muscle weakness or fatigue, which affected 63% of the study participants. The authors report that 26% of the participants had difficulty sleeping, and 23% had anxiety or depression.
Of those who completed the lung function test, the researchers found a correlation between the severity of the person’s initial COVID-19 infection and their lung function at the follow-up.
As many as 56% of the people who required ventilation at the hospital experienced a reduced flow of oxygen to the bloodstream at their follow-up. Of those who did not require oxygen, this affected 22%.
There was also a correlation between disease severity and the results of the 6-minute walking test: 29% of people who required ventilation performed below the lower normal range limit compared with 24% of those who did not require oxygen.
In a sample of 822 of the participants, 13% had worse kidney functioning than when they were in the hospital.
Finally, when they looked at the data from the 94 people who had an antibody test, the researchers found that the number of people testing positive for neutralizing antibodies dropped from 96.2% to 58.5%. The average levels of neutralizing antibodies had also dropped — by 47%.
Corresponding author Prof. Bin Cao — from the National Center for Respiratory Medicine, China-Japan Friendship Hospital, and Capital Medical University, Beijing, China — notes, “[b]ecause COVID-19 is such a new disease, we are only beginning to understand some of its long-term effects on patients’ health.”
“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 postdischarge care, particularly for those who experience severe infections.”
– Prof. Bin Cao
“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,” Prof. Cao adds.
The research had some limitations. Firstly, the sample size of those who had antibody level tests was small, so further research is necessary to confirm these findings.
Also, the lung function and exercise capacity of the participants were unknown prior to their infection, making it impossible to confirm that COVID-19 was the cause of the issues related to these factors.
Finally, the study does not show whether the symptoms had remained consistent or whether they had only appeared or worsened after the infection.
Nonetheless, the research is the biggest study of its kind to date, and it supports anecdotal and observational evidence that the medical community needs to take the longer term effects of COVID-19 seriously.