The nonprofit FAIR Health analyzed the health insurance claims of 1.96 million US residents who contracted COVID-19 between February and December 2020. Scientists tracked how they use their health insurance until February 2021.
The study found that within one month or later after infection, 23% of people needed treatment for new health problems. This has been experienced by people of all ages, including children.
About half of the patients who were hospitalized for the infection turned to doctors for help with the consequences of COVID-19. After an illness of moderate or mild severity, 27% of patients needed help, after an asymptomatic infection – 19%.
More than half of the people included in the study suffered asymptomatic COVID-19. The high prevalence of long covid in this group of patients came as a surprise to the researchers.
The most common postcoid health problems, according to this study, were pain (for example, in muscles), difficulty breathing, high blood cholesterol, weakness, and high blood pressure.
The most common problems people faced after COVID-19 varied across different age groups. For example, in children, intestinal disorders were the third most important, and not high cholesterol, as in adults. Most of the postcoid complaints and illnesses were more common in women. However, there were a few exceptions. For example, men were slightly more likely to suffer from inflammation of the heart muscle.
Among the mental problems following COVID-19, anxiety was the most common. It was followed by depression and adjustment disorder.
Among the limitations of this study is the lack of a control group of people who have never had a coronavirus infection. Such a comparison would help to understand how strongly the symptoms that appear after it are associated with COVID-19.