By LAURAN NEERGAARD AP Medical Writer
WASHINGTON (AP) — About 10% of people appear to suffer from COVID long after an omicron infection, a lower estimate than at the start of the pandemic, according to a study of nearly 10,000 Americans that aims to help untangle the mysterious condition.
Early results from the National Institutes of Health study highlight a dozen symptoms that most distinguish long COVID, the catch-all term for sometimes debilitating health conditions that can last months or years after even a mild case of COVID-19.
Millions of people around the world have had a long COVID, with dozens of widely varying symptoms, including fatigue and brain fog. Scientists still don’t know what causes it, why it only strikes certain people, how to treat it – or even how best to diagnose it. Better defining the condition is essential for research to get those answers.
“Sometimes I hear people say, ‘Oh, everyone’s a little tired,'” said Dr. Leora Horwitz of NYU Langone Health, one of the study’s authors. “No, there’s something different about people who have long COVID and that’s important to know.”
The new research, published Thursday in the Journal of the American Medical Association, includes more than 8,600 adults who had COVID-19 at different times during the pandemic, comparing them to 1,100 others who had not been infected.
By some estimates, about 1 in 3 patients with COVID-19 have had a long period of COVID. This is similar to NIH study participants who reported falling ill before the omicron variant began spreading in the United States in December 2021. This is also when the study s is open, and the researchers noted that people who already had long COVID symptoms might have been more likely to enroll.
But around 2,230 patients had their first coronavirus infection after the study began, allowing them to report symptoms in real time – and only around 10% experienced long-term symptoms after six months.
Previous research has suggested that the risk of long COVID has decreased since omicron emerged; its descendants are still spreading.
The big question is how to identify and help those who already have long COVID.
The new study focused on a dozen symptoms that can help define long COVID: fatigue; brain fog; dizziness; gastrointestinal symptoms; Heart palpitations; sexual problems; loss of smell or taste; the thirst; a chronic cough; chest pain; worsening of symptoms after abnormal activity and movement.
The researchers assigned symptom scores, seeking to establish a threshold that could potentially help ensure that similar patients are enrolled in studies of possible long-term COVID treatments, within the NIH study or elsewhere, for a apples to apples comparison.
Horwitz stressed that doctors shouldn’t use this list to diagnose someone with long COVID — it’s only a potential research tool. Patients may have one or more of these symptoms – or other symptoms not listed – and still suffer long-term consequences of the coronavirus.
Everyone is doing studies on long COVID, but “we don’t even know what that means,” Horwitz said.
The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Science and Education Media Group. The AP is solely responsible for all content.