Risk Factors for Multisystem Inflammatory Syndrome in Children: A Case-control Investigation

Pediatr Infect Dis J. 2023 Jun 1;42(6):e190-e196. doi: 10.1097/INF.0000000000003900. Epub 2023 Mar 16.


Background: In a 2020 pilot case-control study using medical records, we reported that non-Hispanic Black children were more likely to develop multisystem inflammatory syndrome in children (MIS-C) after adjustment for sociodemographic factors and underlying medical conditions. Using structured interviews, we investigated patient, household, and community factors underlying MIS-C likelihood.

Methods: MIS-C case patients hospitalized in 2021 across 14 US pediatric hospitals were matched by age and site to outpatient controls testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within 3 months of the admission date. Caregiver interviews queried race/ethnicity, medical history, and household and potential community exposures 1 month before MIS-C hospitalization (case-patients) or after SARS-CoV-2 infection (controls). We calculated adjusted odds ratios (aOR) using mixed-effects multivariable logistic regression.

Results: Among 275 case patients and 496 controls, race/ethnicity, social vulnerability and patient or family history of autoimmune/rheumatologic disease were not associated with MIS-C. In previously healthy children, MIS-C was associated with a history of hospitalization for an infection [aOR: 4.8; 95% confidence interval (CI): 2.1-11.0]. Household crowding (aOR: 1.7; 95% CI: 1.2-2.6), large event attendance (aOR: 1.7; 95% CI: 1.3-2.1), school attendance with limited masking (aOR: 2.6; 95% CI: 1.1-6.6), public transit use (aOR: 1.8; 95% CI: 1.4-2.4) and co-resident testing positive for SARS-CoV-2 (aOR: 2.2; 95% CI: 1.3-3.7) were associated with increased MIS-C likelihood, with risk increasing with the number of these factors.

Conclusions: From caregiver interviews, we clarify household and community exposures associated with MIS-C; however, we did not confirm prior associations between sociodemographic factors and MIS-C.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • COVID-19* / epidemiology
  • Case-Control Studies
  • Child
  • Crowding
  • Family Characteristics
  • Humans
  • Risk Factors
  • SARS-CoV-2
  • Systemic Inflammatory Response Syndrome / epidemiology

Supplementary concepts

  • pediatric multisystem inflammatory disease, COVID-19 related