Even as national institutions struggle to coordinate meaningful trials of possible long-term COVID treatments, researchers continue to count the damage. New findings suggest that the disease’s reach isn’t just long: it’s still growing.
Three years after their first bouts of COVID-19, patients who had been hospitalized with the virus remained at a “significantly elevated” level.» risk of death or worsening health due to prolonged COVID complications, according to an article published May 30 in Natural medicine.
Even among those whose initial cases did not require a hospital stay, the threat of long COVID and many of its associated problems remain real, the researchers found. And cumulatively, at three years, long COVID gives 91 disability-adjusted life years (DALYs) per 1,000 people – DALYs being a measure of years lost due to poor health or premature death. This is a higher incidence than heart disease or cancer.
“People develop a new disease following an infection they had three years ago,” says Dr. Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis and lead author of the study. “This challenges the idea that these viruses are somehow self-sustaining or that after the first acute phase they become inconsequential. »
With more than 130,000 patients, the study is by far the largest conducted to date to track the progression of the virus over a full three-year period. It expands on work by Al-Aly and others over the past two years, which found that patients were at high risk of long-term COVID-related illnesses, including diabetes, lung problems, fatigue, blood clots and gastrointestinal and musculoskeletal disorders.
At three years old, Al-Aly says Fortune, The main complications among people with mild initial cases of COVID were found in the neurological, gastrointestinal and pulmonary systems. The continuing risk among those who had been hospitalized extended across seven organ systems and included serious illnesses such as strokes, heart attacks, heart failure and even Alzheimer’s disease.
The study included nationally renowned researchers Al-Aly and co-author Dr. Eric Topol, executive vice president and professor of molecular medicine at Scripps Research. He relied on patients from the St. Louis Veterans Affairs health system. As such, the scientists note, the demographics are more male, white, and slightly older than other patient studies.
“The data is encouraging in that no new adverse health problems were noted during the third year after infection. » says Akiko Iwasaki, director of the Center for Infection and Immunity at Yale University School of Medicine. But Iwasaki, who was not involved in the study, cautioned that some post-acute infectious diseases can appear years later. “We will need to keep these types of long-term follow-up studies going for extended periods of time,” she says.
More health challenges for hospitalized patients
Unsurprisingly, those whose first cases of COVID required hospitalization faced the greatest challenges during the three-year study, a grim reminder that interventions such as vaccination and antivirals are essential, says Al-Aly. (Those who participated in the study were all recruited in 2020, meaning they were infected largely before vaccines and antivirals were available.)
“The story of those hospitalized is darker,” explains the researcher. “They are at greater risk and a longer risk horizon, with a disease burden astronomically higher than that of uninfected individuals and higher than that of non-hospitalized individuals. Preventing hospitalizations is very important.
The risk of new long COVID complications decreased over time for both hospitalized and non-hospitalized patients, the study found. “That’s the good news,” says Al-Aly. The risk of death, meanwhile, became “insignificant” after the first year among those who did not need to go to hospital, i.e. most of us who already been infected with COVID.
However, for those whose cases required hospitalization, the threat of death “remained consistently high even into the third year,” the researchers said. This group also faced a much greater health burden: about 90 DALYs per 1,000 people, compared to about 10 DALYs per 1,000 for the nonhospitalized group. (For context, heart disease and cancer cause about 50 DALYs per 1,000 people.)
“The difference in DALYs between the two groups should not be interpreted to mean that people with long COVID from less severe acute illness are not suffering much due to their long COVID symptoms,” says Dr. David Putrino, director of the Cohen Center. for Recovery from Complex Chronic Illness at Mount Sinai School of Medicine. “This simply means that after three years, they suffer fewer obviously life-threatening aftereffects” than those who initially had to be hospitalized.
The stubborn presence of long COVID reinforces the idea that this is no ordinary virus. Scientists believe viral persistence, chronic inflammation and immune system dysfunction come into play, although more study is needed.
What are the prospects for fighting long COVID?
As for the question of what the term long COVID actually means — that is, how long it lasts — the science is still developing, Al-Aly says. He describes long COVID as “this sort of complex web of 80 or more different health conditions,” some of which, like stroke or heart disease, could negatively impact patients for the rest of their lives.
“We don’t know what we don’t know,” says Al-Aly. “It’s only after three years… We don’t know what’s going to happen in 10 years.” The research group hopes to persuade its funders to continue following the patient cohort for at least that long, he said.
For these and other reasons, researchers have taken the initiative to accelerate the pace of trials of long-term COVID treatments, early efforts of which were criticized for wasting money and critical time. Appearing before a U.S. Senate committee in January, Al-Aly told committee members that at least 20 million people in the country had been affected by long COVID. Globally, this number is estimated to be at least 65 million.
This meeting was notable in part because it represented the first congressional hearing on long COVID since the pandemic began. Researchers hope this latest study will bring renewed attention to a long-tail disease with an unknowable future, and perhaps prompt the National Institutes of Health to further address the problem.
“We need to be much bolder and more ambitious in our trials,” says Al-Aly. “At the glacial pace at which they are evolving, we are unlikely to get definitive answers for decades to come.”