"Longer follow-up studies in a larger population are necessary to understand the full spectrum of health consequences from Covid-19." the researchers conclude.
The participants underwent a series of questionnaires, physical examinations, a six-minute walking test and blood tests by trained healthcare professionals to gather the data.
"Our analysis indicates that most patients continue to live with at least some of the effects of the virus after leaving the hospital, and highlights a need for post-discharge care, particularly for those who experience severe infections", said Bin Cao, Professor at the Capital Medical University in Beijing, China.
Follow-up blood antibody tests from 94 patients after six months revealed that levels of neutralising antibodies were 52.5 per cent lower than at the height of infection.
The study found that 76% of COVID-19 patients had at least one symptom six months after the initial onset of the illness.
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It is still unclear whether many of these persistent symptoms are directly caused by the disease or other underlying health issues, Cao said.
Nearly two-thirds of those followed still experienced fatigue or muscle weakness half a year after their acute illness, while 26% had sleep difficulties and 23% had anxiety or depression, according to the peer-reviewed study of 1,733 patients in The Lancet medical journal. Sleep difficulties, anxiety, and depression were also commonly reported.
"The decline of neutralizing antibodies observed in the present study and other studies raises concern for SARS-CoV-2 reinfection", the researchers wrote, adding that "the risk of re-infection should be monitored for patients who present with compatible symptoms of Covid-19".
Nevertheless, they described the study by Huang and colleagues as "relevant and timely", noting that more than half of the cohort presented with residual chest imaging abnormalities and that disease severity during acute illness was independently associated with extent of lung diffusion at follow-up. But the coronavirus has been found to affect almost every part of the body, and the first sign of your infection can be a pretty obscure one (or you could have no coronavirus symptoms at all).
The findings also suggest that patients with more severe disease performed worse in the six-minute walking test. Researchers also found that 13 per cent of the patients whose kidney function was normal while in the hospital had reduced kidney function in their follow-up.
The new study included 1,733 Covid-19 patients discharged from Jinyintan Hospital in Wuhan between January and May past year.
A total of 1 733 of discharged Covid-19 patients from Jin Yin-tan Hospital between 7 January and 29 May 2020 were enrolled in the study.
Fred Pelzman, an associate medical director of Weill Cornell Internal Medicine Associates, a hospital in NY that was not involved in the study, said the experience of patients in China is similar to what has been seen in the US.