A study of nearly 2 million coronavirus patients across the country found that about a quarter developed at least one long-COVID symptom such as “brain fog,” breathing difficulties or high cholesterol 30 days or more after initially testing positive.
However, 19% who never felt sick during their infection later became a long-hauler, as those who go on to experience persistent symptoms for more than four weeks after diagnosis have come to be called.
Meanwhile, about 28% of those who had symptoms but were not hospitalized and 50% of patients who were admitted to the hospital went on to develop long-COVID, according to the study published Tuesday by the nonprofit FAIR Health.
As for risks of death among long-haulers, the odds were 46 times higher for people who were hospitalized and later discharged than those who were never admitted.
The study was based on data of over 34 billion private health care claim records of patients who got infected with the virus between February and December 2020, containing “the largest population of COVID-19 patients ever studied for long-haul COVID,” according to FAIR Health.
Because only those with private insurance or Medicare Advantage (only Part C) were included in the research, the findings may not fully represent the true scope of long-COVID health problems in the U.S. population.
“Even as the COVID-19 pandemic wanes, long-haul COVID persists as a public health issue affecting many Americans,” FAIR Health President Robin Gelburd said in a statement. “The findings in our new study shed significant light on this emerging issue for all individuals who have long-haul COVID, as well as for policy makers, providers, payors and researchers.”
The most common long-COVID conditions found across all age groups were muscle pain, breathing difficulties, high cholesterol, fatigue and high blood pressure, most of which were more associated with females than males.
Mental health conditions that long-haulers most often experienced were anxiety, depression, adjustment disorders and tourette’s disorders that involve compulsive, repetitive sounds or movements that are often difficult to control.
Patients with certain preexisting conditions such as cancer or chronic kidney disease were excluded from the study. However among those that were included, people with intellectual disabilities faced the highest risks of death during their bout with long-COVID.
Doctors still don’t know what causes people to experience symptoms months after initial infection, but some speculate small levels of the coronavirus hiding in the body are to blame. Others think people’s immune systems may be stuck on auto-pilot or that damage from the coronavirus may have injured nerve pathways that are slow to heal.