Many ‘Long Covid’ patients had no symptoms of their initial infection

Many people with long-term symptoms of the coronavirus did not feel sick at all when they were first infected, according to a new study that adds compelling information to the growing question of l lasting impact of Covid-19 on health.

The study, one of the first to focus exclusively on people who never needed hospitalization when infected, analyzed the electronic medical records of 1,407 people in California who tested positive for the coronavirus. More than 60 days after their infection, 27%, or 382 people, were struggling with post-Covid symptoms such as shortness of breath, chest pain, cough or abdominal pain.

Nearly a third of patients with such long-term problems had no symptoms of their initial coronavirus infection within 10 days of testing positive, the researchers found.

Understanding the long-term symptoms of Covid is an increasingly urgent priority for doctors and researchers as more people report debilitating or painful sequelae that hamper their ability to work or function as they once did. . Last month, the Director of the National Institutes of Health, Dr Francis S. Collins, announced a major initiative “to identify the causes and ultimately the means of prevention and treatment of people with Covid-19, but not recovering completely 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 the Mount Sinai post-Covid care center were seeing a pattern similar.

“Many people with asymptomatic Covid can also develop post-acute Covid syndrome,” said Dr Putrino, who is co-author of a smaller study on the subject published last year. “It doesn’t always correspond to the severity of acute symptoms, so you may have no symptoms while having a very aggressive immune response.”

The new study is posted on the MedRxiv pre-print site and has not finished undergoing peer review. Its strengths include that it is larger than many long-term symptom studies published so far and that the researchers used electronic records from the University of California system, allowing them to obtain information. on the health and demographics of patients statewide. The researchers also excluded from the study symptoms that patients had reported in the year before their infection, a step intended to ensure a focus on post-Covid symptoms.

Among their findings: Long-term problems affect all age groups, including children. “Of the 34 children in the study, 11 were long haul,” said one of the authors, Melissa Pinto, 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 issues, and rapid heart rate. The researchers identified five groups of symptoms that seemed most likely to occur together, such as chest pain and cough or abdominal pain and headache.

Most previous studies of long-term symptoms have tended to involve people sick enough from their initial infection to be hospitalized. One of the largest revealed that more than three-quarters of 1,700 patients hospitalized in Wuhan, China had at least one symptom six months later.

But increasingly, people who have never been hospitalized are seeking care in post-Covid clinics, and scientists are recognizing the need to understand their situation.

Last month, researchers at the University of Washington reported on a survey of 177 people who had tested positive for the coronavirus. Most of them had not been hospitalized. About a third of people who had been hospitalized and people who had only mild initial illnesses reported having at least one lasting symptom six months later, the researchers found.

Unlike some recent surveys, like one conducted by a patient-led research team, the new study failed to capture one of the most commonly reported ‘long covid’ issues: cognitive issues such as brain fog , memory problems and difficulty concentrating. One of the co-authors, Natalie Lambert, an associate research professor at Indiana University School of Medicine, said this could be because doctors at the time did not know maybe not that they included diagnostic codes for these cognitive issues in the medical records of Covid patients. The team is seeking funding for a larger and more comprehensive study that combines information from medical records, doctor’s notes and patient reports, she said.

In the new study, about 59 percent of patients with long-term symptoms were female, and about half of the patients were Hispanic and 31 percent were white. The authors and Dr Putrino cautioned that any reliable demographic conclusion would require larger studies of national scope.

Dr Lambert said it was likely that the medical records used in the study only reflected a percentage of people who had asymptomatic Covid infections and sequelae of Covid. “For some people, if they’re asymptomatic and they don’t know they’re sick, they’re not going to get tested,” she said.

“Another important point is that we know that some of the long-term symptoms show up much later than two months,” said Dr Lambert. “So there is potential for a wide range of long-term symptoms that they will not associate with Covid.”

Dr Pinto said it would be important to study the disease over time, rather than in a static snapshot. “The long term is a very dynamic process and the symptoms can change from day to day,” she says. “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 pain. We need to capture the trajectory and evolution of symptoms over time, and we need it in a larger sample that represents America. “