Even two years after their initial infection, the majority of people who were hospitalized with Covid-19 early in the pandemic had lingering symptoms, according to a new study that may be one of the longest and largest on record to follow people with long Covid.
The study, published Wednesday in The Lancet, found that 55% of patients still had at least one Covid-19 symptom two years later. That was actually an improvement from six months after infection, when 68% had symptoms.
The researchers from China-Japan Friendship Hospital looked at the records of 1,192 people who had been hospitalized at Jin Yin-tan Hospital in Wuhan, China, and were discharged between January 7 and May 29, 2020.
The researchers checked in six months, 12 months and two years after the patients were discharged and asked for their subjective assessment of symptoms. The participants were also assessed using more objective medical tests including pulmonary function tests, CT scans and six-minute walk tests.
In general, the participants had poorer health two years later. Those who had lingering Covid-19 symptoms listed pain, fatigue, problems sleeping and trouble with their mental health. Patients who had higher-level respiratory support while hospitalized had more lung problems than others in the long term.
The participants with lingering symptoms also went to the doctor more often than they did pre-pandemic. They had a harder time exercising and generally reported a poorer quality of life. Most were back at work, but it’s not clear whether they were working at the same level as before they got sick.
Study co-author Dr. Bin Cao of China-Japan Friendship Hospital hopes the research will encourage doctors to ask follow-up questions with their patients who had Covid-19, even years after their initial infection.
“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 in a news release.
The study has some limitations. The researchers did not compare the results to people who were hospitalized for non-Covid reasons to see if they too had lingering symptoms. They compared the hospitalized group to people in the community who never had Covid-19; that group also had health problems a year later, but that happened in only about half as many people as in the hospitalized group.
Another limitation was that the research involved a single hospital, so the results may not be universal for all hospitalized Covid-19 patients. Earlier in the pandemic, patients were typically kept in the hospital for longer than they are now, and that could have an effect on how long someone had symptoms. And because the research was done early in the pandemic, it’s unclear whether there would be similar results in people who got sick with later variants of the coronavirus or in those who had been vaccinated.
Dr. Devang Sanghavi, a critical care specialist who does research on long Covid and works with long Covid patients at Mayo Clinic in Jacksonville, Florida, hopes future long Covid studies will include vaccination status.
“The only thing I know that I can safely offer long Covid patients is vaccination,” said Sanghavi, who was not involved in the study. “When we compare nonvaccinated patients to vaccinated patients and see the incidence of symptoms of long Covid, vaccinated patients have less severe symptoms and less commonly have long Covid.”
Like the authors, Sanghavi hopes the study will help policymakers realize how important it is to fund research on long Covid and build out infrastructure to better accommodate long-haul patients. There could be millions of people with long Covid, studies suggest.
“Right now, these patients sometimes seem to be an afterthought,” Sanghavi said.
“The study points out potentially how many people will need help. I don’t know if you’ve tried to get an appointment for primary care visit, but it takes potentially weeks or even months in many places. And that’s just for a simple wellness check – forget about long Covid. That’s a lot longer,” he said.
Sanghavi said more doctors will also need to be trained in how to help people with long Covid. “Our health-care system is not prepared for the kind of influx of patients that this condition will bring,”
Dr. Kristine Erlandson, an associate professor of medicine and infectious disease specialist at the University of Colorado, has been doing her part by recruiting participants for a study of the long-term impact of Covid-19. The initiative is a part of the National Institutes of Health’s RECOVER trial.
Erlandson said that so many people want to know more about long Covid that her colleagues haven’t even had to advertise the trial; there’s a waiting list to get in.
The new research lines up with what staffers are seeing at those long-haul clinics.
“This is similar to what we hear patients in the US saying, that they’re still experiencing symptoms at two years out, particularly in that first spate of patients in the pandemic. We’ve been hearing this anecdotally, so it’s always nice to see things published,” said Erlandson, who was not involved in the study. Patients in her clinic also have similar symptoms, with sleeping difficulties and fatigue the most common.
She emphasized that people don’t have to be hospitalized for Covid-19 to have lingering symptoms, and she hopes future research will capture how long nonhospitalized people experience symptoms.
Erlandson also noted that some of the study participants got better after 12 months but then worse again after two years.
“I think these long studies are interesting to see it’s not a progressive improvement. People are kind of fluctuating in terms of their improvements,” she said.
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Erlandson said she will be curious about whether the participants got better beyond those two years or whether Covid-19 will turn out to be a chronic condition. Doctors can treat certain symptoms, but there is no specific treatment for long Covid.
“Unless they have some kind of treatments, I do worry that it is going to have some long-term impact on on disability and in function for some patients,” she said.