Two years after infection with Covid-19, half of patients who were admitted to hospital still have at least one symptom, according to the study published in The Lancet Respiratory Medicine.
The study followed 1,192 participants in China infected with SARS-CoV-2 during the first phase of the pandemic in 2020.
While physical and mental health generally improved over time, the analysis suggests that Covid-19 patients still tend to have poorer health and quality of life than the general population.
This is especially the case for participants with long Covid, who typically still have at least one symptom including fatigue, shortness of breath, and sleep difficulties two years after initially falling ill.
"Our findings indicate that for a certain proportion of hospitalised Covid-19 survivors, while they may have cleared the initial infection, more than two years is needed to recover fully from it," said lead author Professor Bin Cao, of the China-Japan Friendship Hospital, China.
Six months after initially falling ill, 68 per cent of participants reported at least one long Covid symptom. By two years after infection, reports of symptoms had fallen to 55 per cent.
Fatigue or muscle weakness were the symptoms most often reported and fell from 52 per cent at six months to 30 per cent at two years.
Covid-19 patients were also more likely to report a number of other symptoms including joint pain, palpitations, dizziness, and headaches, pain or discomfort and anxiety or depression than non-Covid-19 participants.
Long Covid participants also more often reported problems with their mobility or activity levels than those without long Covid.
The authors also acknowledge limitations such as lack of control group of hospital survivors unrelated to Covid-19 infection.
The team emphasised the need for follow-up of Covid survivors, particularly those with symptoms of long Covid.
"There is a clear need to provide continued support to a significant proportion of people who've had Covid-19, and to understand how vaccines, emerging treatments, and variants affect long-term health outcomes," Cao said.
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