(ASPOT06) Comorbidity associated with COVID-19 hospitalisation among 135,000 children and adolescents with SARS-CoV-2 infection during their initial COVID-19 vaccination campaign in Spain

Background: Several clinical conditions have been previously associated with the severe prognosis of SARS-CoV-2 infection among the youngest population. The research on large populations is required to confirm it.

Objectives: To identify clinical factors associated with COVID-19 hospitalisation among children and adolescents with SARS-COV-2 infection using electronic health records.

Methods: The Spanish Database For Pharmacoepidemiological Research in the Public Setting (BIFAP) was used. Two cohorts (children aged 5-11 years and adolescents aged 12-18 years) from December 2021 and July 2021, respectively, were followed up to a SARS-CoV-2 positive test or May 2022. Among them, hospitalizations due to COVID-19 were identified through manual review of the clinical histories of patients admitted to hospital or ICU with a SARS-CoV-2 positive test from -30 to +120 days. Clinical factors measured at baseline were compared between hospitalised and non-hospitalised patients with SARS-CoV-2 infection through multivariate logistic regression (Odds Ratio-OR; 95% CI) adjusted by age, sex, region, calendar month, healthcare visits and polymedication.

Results: Among 731,461 children, 65,305 had a SARS-CoV-2 positive test and 228 of them required hospitalization/ICU. Among 741,585 adolescents, 70,314 had a positive test and 201 were hospitalized. The hospitalizations due to COVID-19 increased amongst children with epilepsy (3.69; 2.01-6.76), eating disorders (2.07; 1.12-3.85) and cardiovascular disease (CV) (1.59; 1.01-2.48). OR decreased in those vaccinated against COVID-19 (0.61; 0.45-0.81). Similarly, hospitalizations increased amongst adolescents with anaemia (1.66; 1.19-2.32), obesity (1.81; 1.27-2.56), epilepsy (2.46; 1.39-4.36) and immunodeficiency (4.74; 2.05-11.00). OR decreased amongst adolescents with asthma (0.61; 0.37-1.00) and vaccinated against COVID-19 (0.64; 0.43-0.93). Other factors (malignancy, asthma inhalers, vitamin D supply or deficiency) were not associated.

Conclusions: A history of immunodeficiency, CV or epilepsy increased the risk of COVID-19 hospitalizations among children and adolescent with SARS-CoV-2 infections during last Delta and early Omicron variant periods. That agrees with the literature and suggests vulnerability to COVID-19 complications. Disruption of essential nutrient intake produced by eating disorders or nutritional deficiencies can weaken the immune system and increase susceptibility to COVID-19. The protection suggested with the COVID-19 vaccination pointed towards the effectiveness observed previously. These findings provide information for decisions-making regarding public health recommendations for COVID-19 complications prevention among the paediatrics.