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Largest Study of Lingering COVID-19 Effects Suggests a Looming Problem

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In the largest long-term study of COVID-19 patients yet to be published, researchers in China report in the Lancet worrying results of the disease’s lingering impact on people’s health.

The scientists, led by Dr. Bin Cao from the China-Japan Friendship Hospital in Beijing, studied 1,276 people discharged between January to May 2020 from Jin Yin-Tan Hospital in Wuhan after being hospitalized for COVID-19. The patients all agreed to health visits at six and 12 months after their symptoms first appeared; at each of those points, the researchers compared the health status of the study participants with that of comparable people from the Wuhan area who did not experience COVID-19 infection.

Among those hospitalized for COVID-19, 68% reported at least one continued, COVID-19-related symptom six months after their first symptoms appeared. While this percentage decreased by the 12-month mark, it remained relatively high, at 49%. And overall, patients who had been hospitalized for COVID-19 self-reported being in poorer health and having lower quality of life—including mobility issues— compared to controls.

The most common symptom patients reported 12 months later was fatigue or muscle weakness; other issues included sleep disturbances, changes in taste and smell, dizziness, headache and shortness of breath. Certain symptoms were actually worse at the 12-month mark than they were earlier on in the study: the proportion of patients reporting breathing problems increased slightly, from 26% to 30%, from six months to a year following their first symptoms. The patients also filled out questionnaires about their mental health, and while 23% reported feeling anxious or depressed six months after their first symptoms appeared, 30% did so at a year.

The findings highlight the complicated nature of COVID-19’s effects on people’s health, and the range of longer-term consequences emerging in what some experts are referring to as Long COVID. This recent study is the largest to date of such extended effects among hospitalized patients; while it suggests that about half of patients with serious COVID-19 recover from their symptoms, the other half—and especially those who were sicker during their hospitalization—may continue to battle the mental and physical effects of the virus for over a year.

“I would not say this is a glass-half-full story,” says David Putrino, director of rehabilitation innovation at Mount Sinai Health Systems who oversees the network’s Long COVID rehabilitation program. “After most hospital stays, including for, say, walking pneumonia, I would not be expecting people at 12 months to still be reporting symptoms to me.”

The increase in the proportion of patients experiencing anxiety or depression is especially “worrying,” say the authors, and they speculate that in addition to the isolation, unemployment, and loss of physical health that could be fueling these conditions, the virus itself may be driving abnormal immune responses that could affect the delicate work of brain chemicals contributing to people’s mental states.

“Taken together, the implications are that people with persistent COVID-19 symptoms are looking at a long recovery,” says Putrino. At Mount Sinai’s Long COVID program that involves a personalized approach to addressing patients’ diverse symptoms, which could range from kidney, heart and lung problems to generalized fatigue and muscle weakness. For the latter, rehabilitation might include a tedious process of gradually stimulating the autonomic nervous system with carefully supervised exercises to slowly stimulate normal nerve activation, which could take as long as three to four months before patients feel better.

“This virus doesn’t end once you get discharged from the hospital or once you get over the initial acute symptoms,” says Putrino. “This virus persists.” He notes that while the recent Lancet study only focused on hospitalized COVID-19 patients, other, albeit smaller, studies have shown that COVID-19 symptoms may linger in around 20% of those who get infected but don’t get sick enough to go to the hospital.

That means the issue of persistent COVID-19 symptoms looms over any post-COVID-19 public health plan; currently, there isn’t much clarity about whether, or how much, insurers will cover rehabilitation for these patients. And that’s if patients know of and can access these services to begin with. “It’s the tip of the iceberg of enormous potential inequity and disparities in health,” says Putrino. “Most persistent symptoms are invisible symptoms, and walking into a doctor’s office and saying you have extreme fatigue”—a symptom many COVID-19 sufferers have reported experiencing months after infection—”[only] gets treated seriously when you’re not a member of a historically excluded group. And when you are, in many cases you don’t bother to even go to the doctor’s office because who is going to believe you?”

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