A retroactive study found multisystem inflammatory syndrome in children was more common and more severe than previously reported.
The study, published in JAMA Network Open on Jan. 5, looked at COVID-19 and MIS-C hospitalizations in 31 states between February and October 2021 for individuals younger than 21. There were 4,107 individuals with MIS-C and 23,686 individuals with COVID-19 without MIS-C.
The study compared reported numbers in their analysis. They found the following as the number of organ systems affected increased from two to six or more:
- Mortality from MIS-C increased from 1 percent to 6 percent.
- Adverse medication events due to MIS-C increased from 5 percent to 18 percent.
- The length of stay doubled from four to eight days for MIS-C patients.
- Median costs for MIS-C increased from $16,225 to $53,359.
- The percentage of patients with MIS-C who were Black doubled from 16 percent to 32 percent.
- Hospital stays for MIS-C increased by one day for Black patients compared with White patients, with Black patients moving from the bottom to top quartile of socioeconomic vulnerability, with no disparity with COVID-19.
- Researchers concluded that relying on mean outcomes for MIS-C from past studies can be misleading, because outcomes and disparities varied widely with the number of multiorgan dysfunctions, according to the report.