NEW YORK (NYTIMES) - One year after becoming ill with the coronavirus, nearly half of patients in a large new study were still experiencing at least one lingering health symptom, adding to evidence that recovery from Covid-19 can be arduous and that the multifaceted condition known as "long Covid" can last for months.
The study, published Thursday (Aug 26) in the journal Lancet, is believed to be the largest to date in which patients were evaluated one year after being hospitalised for Covid-19.
It involved 1,276 patients admitted to Jin Yin-tan Hospital in Wuhan, China, who were discharged between Jan 7 and May 29, 2020.
The researchers, who also evaluated the patients six months after hospitalisation, found that while many symptoms improved over time and many of the 479 people who had been employed when they got Covid-19 had returned to their original job, 49 per cent of patients still had at least one health problem.
And shortness of breath and mental health issues such as anxiety or depression were slightly more prevalent 12 months later than at the six-month mark, the researchers reported, saying the reasons for that "worrying" increase were unclear.
The researchers also compared the patients in the study with people in the community who had not had Covid-19 but had similar pre-existing health conditions and other characteristics.
After 12 months, Covid-19 survivors had worse overall health than people who had not been infected.
They were also much more likely to be experiencing pain or discomfort, anxiety or depression, and mobility problems than those who had not had the disease.
The patients, whose median age was 57, were given physical exams, lab tests and a standard measure of endurance and aerobic capacity called a six-minute walk test. They were also interviewed about their health.
The study involved patients who were sick enough to be hospitalised, but who were generally not the most severely debilitated.
About 75 per cent required supplemental oxygen when they were hospitalised, but most did not need intensive care, ventilators or even high-flow nasal oxygen, a noninvasive method.
Women were more likely than men to have some lingering symptoms, including mental health issues and lung function problems.
One of the most common symptoms was fatigue or muscle weakness, reported by 20 per cent of patients.
But that represented a significant decrease from the 52 per cent who reported such symptoms six months after hospitalisation.
Some issues, such as shortness of breath, were more common in people who had been more severely ill.
But some issues did not correlate to severity of the initial illness. For example, 244 patients underwent a lung-function test, which found that from six months to one year after hospitalisation, there was no decrease in the proportion of patients with reduced flow of oxygen from their lungs to their bloodstream - regardless of how ill the patients had been initially.
"The need to understand and respond to long Covid is increasingly pressing," said an editorial that Lancet published about the study.
"Symptoms such as persistent fatigue, breathlessness, brain fog and depression could debilitate many millions of people globally."
It added: "Long Covid is a modern medical challenge of the first order."