Which Kids Are More Likely to Develop MIS-C?

— Large U.S. pediatric cohort examined variables that contribute to higher risk

MedicalToday
A little Black boy wearing a protective mask gives the thumbs down gesture

After a SARS-CoV-2 infection, several demographic and clinical factors were more likely to predict multisystem inflammatory syndrome in children (MIS-C), some of which overlapped with risks for severe COVID-19, analysis of a large pediatric cohort found.

Male sex, Black race, age younger than 12 years, and obesity were all associated with increased odds of MIS-C versus acute COVID-19 infection, reported Blake Martin, MD, of the University of Colorado School of Medicine in Aurora, and colleagues.

MIS-C was also associated with a more severe clinical phenotype, with higher rates of invasive ventilation and cardiovascular support, they noted in .

The National COVID Cohort Collaborative was characterized as "the largest U.S. pediatric SARS-CoV-2 cohort at the time of the study." Martin and colleagues collected data from 56 facilities through Sept. 24, 2021, which included some data on the Delta variant wave, for children ages 18 and younger who were tested for SARS-CoV-2.

Overall, 1,068,410 children were tested, with 15.6% of results coming back positive. Median age of patients was 11.9, with an even gender split. Of the 167,262 who tested positive, 6.1% were hospitalized.

Among the 10,245 hospitalized kids, 13.9% had severe disease, 7.8% of these patients required mechanical ventilation, 8.5% required vasopressor-inotropic support, 0.4% required extracorporeal membrane oxygenation, and 1.3% died.

In this study, 707 children met the criteria for MIS-C, and 36.9% met criteria for severe disease. Martin's group found that certain variables were associated with increased risk of MIS-C versus acute COVID (all P<0.001):

  • Male sex (OR 1.59, 95% CI 1.33-1.90)
  • Black race (OR 1.44, 95% CI 1.17-1.77)
  • Age under 12 (OR 1.81, 95% CI 1.51-2.18)
  • Obesity (OR 1.76, 95% CI 1.40-2.22)

Certain factors were protective for MIS-C, such as not having a pediatric complex chronic condition (OR 0.72, 95% CI 0.65-0.80), the authors noted.

A higher proportion of kids with MIS-C required invasive ventilation (16.5% vs 6.2% of those with acute COVID) and vasoactive-inotropic support (27.0% vs 5.2%, respectively; P<0.001 for both). For all 18 laboratory tests, kids with MIS-C had a higher proportion of abnormal values versus those with acute COVID.

While the majority of the study took place outside of the time period when the Delta variant was predominant, Martin and team did look at Delta era data versus pre-Delta era data, and found that of the nearly 30,000 encounters in the Delta era, there was no significant difference in the proportion of children hospitalized (6.0% vs 6.2%, respectively, P=0.18).

Limitations to the study included the fact that the data were aggregated from a number of health systems, some respiratory data were not fully available, and timing of specimens was inconsistently provided by laboratory sites.

Martin and colleagues added that they also could not definitively attribute the reason for hospital admission to COVID versus an unrelated cause, given the number of asymptomatic to minimally symptomatic pediatric infections and more adoption of universal testing for pediatric hospitalizations.

  • author['full_name']

    Molly Walker is deputy managing editor and covers infectious diseases for . She is a 2020 J2 Achievement Award winner for her COVID-19 coverage.

Disclosures

Multiple institutes of the NIH sponsored the study.

The National Center for Advancing Translational Sciences is the primary steward of the N3C data and created the underlying architecture of the N3C Data Enclave, manages the data transfer agreements and data use agreements, houses the data access committee, and supports contracts to vendors to help build various aspects of the N3C Data Enclave.

Martin disclosed no conflicts of interest.

Other co-authors disclosed support from the NIH, NIH/National Center for Advancing Translational Sciences, Oregon Health and Science Institution, University of Colorado-Anschutz, Pryzm Health, the National Institute of Allergy and Infectious Diseases, and the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

Primary Source

JAMA Network Open

Martin B, et al "Characteristics, outcomes, and severity risk factors associated with SARS-CoV-2 infection among children in the US National COVID Cohort Collaborative" JAMA Netw Open 2022; DOI: 10.1001/jamanetworkopen.2021.43151.