A US study has found that as with adults, the same clinical factors affect COVID-19 severity and hospitalisation in children and adolescents.
The available evidence clearly shows that infection with COVID-19 is disproportionately higher in adults compared with children. Nevertheless, emerging data suggests that in children infection with COVID-19 can induce multisystem inflammatory syndrome and lead to serious illness. While the pandemic has revealed how several clinical factors such as older age, various co-morbidities and ethnicity, are all associated with a higher level of COVID-19 severity, much less is known about which factors lead to more severe disease in children.
This lack of information prompted a group of US researchers from the Division of Hospital Medicine, Monroe Carell Jr, Children’s Hospital, Vanderbilt, Nashville, Tennessee, US, to undertake a retrospective cohort study across 45 US children’s hospitals to assess factors associated with COVID-19 severity in paediatric patients. The researchers included patients as young as 30 days old to 18 years of age, discharged from either an emergency department (ED) or inpatient setting with a primary diagnosis of COVID-19. The researcher collected demographic data and information on the presence of any co-morbidities, particularly those which appeared to result in a worse prognosis among adults. The outcome of interest was COVID-19 severity which was categorised as mild (i.e., ED discharge), moderate (in-patient admission) and severe (intensive care (ICU) admission) and very severe (ICU admission with mechanical ventilation, shock or death). The results were analysed using regression analysis and presented as odds ratios adjusted for various factors including ethnicity and co-morbidities.
The study included 19,976 ED encounters of children with a median age of 6 years (51.2% male) with the most common ethnicities being Hispanic (48.8%) and non-Hispanic White (21.1%). In the majority of cases (79.9%) COVID-19 severity was mild (79.7%) and these individuals were discharged from the ED. However, among the 4063 (20.3%) patients who were hospitalised, the majority had moderate COVID-19 severity (79.3%) with 11.3% classed as severe and 9.4% as very severe. When compared with those who were discharged from the ED, the clinical factors associated with an increased odds of hospitalisation included obesity/type 2 diabetes (adjusted Odds ratio, aOR = 10.4, 95% CI 8.90 – 13.3), asthma (aOR = 1.40, 95% CI 1.3 – 1.60), cardiovascular disease (aOR = 5.0), an immunocompromised condition (aOR = 5.9) and pulmonary disease (aOR = 3.2). Only Black ethnicity impacted on the risk of hospitalisation compared to those of White ethnicity, (aOR = 1.52, 95% CI 1.20 – 1.93). With respect to age, compared to children aged 0 – 4 years, the risk of hospitalisation was lower among those aged 5 – 11 years (aOR = 0.50, 95% CI 0.45 – 56) and 12 – 17 years (aOR = 0.75, 95% CI 0.69 – 0.82). However, once hospitalised, the risk of higher COVID-19 severity increased in both groups: 5 – 11 group (aOR = 2.66) and 12 – 17 years (aOR = 2.09).
The authors concluded that while older children were at a lower risk of hospitalisation with COVID-19, once hospitalised, they appeared to be a higher risk of more severe disease. In addition, as with adults, similar co-morbidities were associated with a greater risk of hospitalisation and higher COVID-19 severity once admitted.
Antoon JW et al. Factors associated with COVID-19 disease severity in US children and adolescents. J Hosp Med 2021