Many people who experience long-term symptoms of the coronavirus did not feel sick at all when they were initially infected, according to a new study that adds compelling information to the increasingly important issue of the lasting health impact of Covid-19.
The study, one of the first to focus exclusively on people who never had to be hospitalized when they were infected, analyzed electronic medical records of 1,407 people in California who tested positive for the coronavirus. More than 60 days after their infection, 27 percent or 382 people struggled with post-Covid symptoms such as shortness of breath, chest pain, cough or abdominal pain.
Nearly a third of the patients with such long-term problems had no symptoms of their initial coronavirus infection during the ten days after they tested positive, the researchers found.
Understanding long-term Covid symptoms is an increasingly urgent priority for physicians and researchers as more and more people report debilitating or painful side effects that impair their ability to work or function as in the past. Last month, the director of the National Institutes of Health, dr. Francis S. Collins, announces a major initiative “to identify the causes and ultimately the means of prevention and treatment of individuals affected by Covid-19, but not” to not fully recover in a few weeks . ”
David Putrino, director of rehabilitation innovation at Mount Sinai Health System in New York City, who was not involved in the new research, said he and his colleagues at Mount Sinai’s Center for Post-Covid Care have a similar pattern see.
“Many people who have had Covid asymptomatically may also develop post-acute Covid syndrome,” said Dr. Putrino said. He is co-author of a smaller study on the subject published last year. “It does not always correspond to the severity of acute symptoms, so you may have no symptoms, but still have a very aggressive immune response.”
The new study is published on the preprint website MedRxiv and has not yet undergone peer review. Its strengths are that it is larger than many studies on long-term symptoms published so far, and that the researchers used electronic records from the University of California so that they could obtain health and demographic information from patients from across the state. Acquire. The researchers also excluded the symptoms that patients reported in the year before their infection, a step aimed at ensuring a focus on post-Covid symptoms.
Among their findings: Long-term problems affect every age group, including children. “Of the 34 children in the study, 11 were long-distance caregivers,” said one of the authors, Melissa Pinto, an associate professor of nursing at the University of California, Irvine.
The study found more than 30 symptoms, including anxiety, low back pain, fatigue, insomnia, gastrointestinal problems and rapid heartbeat. The researchers identified five groups of symptoms that are most likely to occur together, such as chest pain and cough or abdominal pain and headaches.
Most previous studies of long-term symptoms tended to involve people who were sick enough from their initial infection to be admitted to the hospital. One of the largest found that more than three-quarters of approximately 1,700 patients in Wuhan, China, had at least one symptom six months later.
But increasingly, people who have never been admitted to the hospital seek out Covid clinics, and scientists are realizing the need to understand their circumstances.
Last month, researchers at the University of Washington reported on a survey among 177 people who tested positive for the coronavirus. Most of them had not yet been admitted to the hospital. About a third of both the people admitted to the hospital and the people who had only mild initial illnesses said they had at least one persistent symptom six months later, the researchers found.
Unlike some recent surveys, such as one by a patient-led research team, the new study did not capture one of the most reported “long Covid” problems: cognitive problems such as brain fog, memory problems, and difficulty concentrating. One of the co-authors, Natalie Lambert, associate professor at Indiana University School of Medicine, said it may be because doctors at the time may not have known they included diagnostic codes for such cognitive problems in the medical records of Covid patients. . The team is seeking funding for a larger and more comprehensive study that combines information in medical records, physician notes and patient reports, she said.
In the new study, about 59 percent of the patients with long-term symptoms were women, and about half of the patients were Hispanic and 31 percent were white. The authors and dr. Putrino warns that any reliable demographic conclusions need larger studies that are of national importance.
Dr Lambert said the medical records used in the study probably only reflect a percentage of people who have had asymptomatic Covid infections and experienced Covid side effects. “For some people, if they are asymptomatic and do not know they are sick, they are not going to be tested,” she said.
“Another important component is that we know that some of the long-distance symptoms appear much later than two months,” said Dr. Lambert said. “So there is a potential for a wide range of long-distance symptoms that they are not going to associate with Covid.”
Dr Pinto said it would be important to study the condition over time, rather than in a static snapshot. “The long distance is a very dynamic process and symptoms can change from day to day,” she said. ‘One day they may have chest pain and headaches, and the next day the chest pain and headaches are gone and they have back pain and muscle aches. We need to capture the trajectory and change of symptoms over time, and we need that in a larger sample that represents America. ‘