Those who had been hospitalized face higher risks of death and complications, but even those with milder infections could see organ damage, researchers say.
Researchers say it’s becoming more clear that symptoms of long covid and the risk of additional complications can endure for two years.
A new study published Monday in Nature Medicine sheds more light on the lingering effects of COVID-19.
Those who required hospital treatment for their initial COVID-19 infection faced greater risks of death and ongoing health challenges. But even those with less severe cases had higher risks of complications, including damage to the heart, lungs, kidneys and other organs.
Researchers say their findings offer more perspective on the health needs of those who have suffered COVID-19 infections.
Here are some of the highlights of the study.
Who was studied
Researchers examined more than 6 million individuals. They studied more than 138,000 with a COVID-19 infection and a control group of about 6 million, and the researchers followed them for two years.
The study also examined health risks and complications among those who were infected with COVID-19 but not hospitalized, and those who were infected and required treatment at a hospital.
Individuals who were hospitalized with a COVID-19 infection face a higher risk of death and hospitalization for two years after infection, the researchers found.
Among those hospitalized individuals, the risks of complications in every organ system remained statistically significantly elevated at two years, the study found. The authors said those findings illustrate “the difficult and protracted road to recovery” for those who required hospital treatment for COVID-19.
For those who didn’t require hospital care for a COVID-19 infection, the risk of death becomes statistically insignificant after six months, according to the study. But those patients still faced an elevated risk of hospitalization up to 19 months after infection.
Even among the group that wasn’t hospitalized, patients had greater risks of cardiovascular, lung, gastrointestinal, kidney, and musculoskeletal complications. They also exhibited higher risk of mental health challenges.
Ziyad Al-Aly, a clinical epidemiologist at Washington University and the senior author of the study, said in a news release that it’s important to understand the enduring symptoms of long covid.
“Our findings highlight the substantial cumulative burden of health loss due to long covid and emphasize the ongoing need for health care for those faced with long covid,” Al-Aly said in the release. “It appears that the effects of long covid for many will not only impact such patients and their quality of life, but potentially will contribute to a decline in life expectancy and also may impact labor participation, economic productivity, and societal well-being.”
The authors point to the need for up-to-date vaccines to lower the likelihood of persistent complications.
“Reducing the risk of infection and transmission with updated vaccines may be a critical strategic avenue to reduce the risk of long-term health loss in populations,” the authors wrote in the study. “Improved uptake of vaccines and antivirals, as well as facilitating access to these across the world, may also help reduce the burden of health loss and stem some of the long-term consequences of SARS-CoV-2 infection.”
Researchers have been working to unravel the mysteries of long covid and the impact on health.
In May, researchers said they identified 12 distinct symptoms of long covid. The findings were published by JAMA. Federal officials called it an important step in assessing patients.
Some patient advocates have been frustrated by the pace of progress in understanding long covid. Some advocate have also said they’d like to see more study on treatments for those suffering complications from infections.
In April 2022, U.S. Sens. Sheldon Whitehouse, D-R.I., and Ed Markey, D-Mass., wrote a letter to the NIH to express their dissatisfaction and urged the agency to move faster on studies of long covid.