Indirect effects of the COVID-19 pandemic on paediatric healthcare use and severe disease: a retrospective national cohort study

Abstract

Objectives: To determine the indirect consequences of the COVID-19 pandemic on paediatric healthcare utilisation and severe disease at a national level following lockdown on 23 March 2020.

Design: National retrospective cohort study.

Setting: Emergency childhood primary and secondary care providers across Scotland; two national paediatric intensive care units (PICUs); statutory death records.

Participants: 273 455 unscheduled primary care attendances; 462 437 emergency department attendances; 54 076 emergency hospital admissions; 413 PICU unplanned emergency admissions requiring invasive mechanical ventilation; and 415 deaths during the lockdown study period and equivalent dates in previous years.

Main outcome measures: Rates of emergency care consultations, attendances and admissions; clinical severity scores on presentation to PICU; rates and causes of childhood death. For all data sets, rates during the lockdown period were compared with mean or aggregated rates for the equivalent dates in 2016-2019.

Results: The rates of emergency presentations to primary and secondary care fell during lockdown in comparison to previous years. Emergency PICU admissions for children requiring invasive mechanical ventilation also fell as a proportion of cases for the entire population, with an OR of 0.52 for likelihood of admission during lockdown (95% CI 0.37 to 0.73), compared with the equivalent period in previous years. Clinical severity scores did not suggest children were presenting with more advanced disease. The greatest reduction in PICU admissions was for diseases of the respiratory system; those for injury, poisoning or other external causes were equivalent to previous years. Mortality during lockdown did not change significantly compared with 2016-2019.

Conclusions: National lockdown led to a reduction in paediatric emergency care utilisation, without associated evidence of severe harm.

Keywords: COVID-19; epidemiology; mortality.

Figure 1

Annotated SARS-CoV-2 epidemic curve for Scotland (A) and key events during the lockdown period (B). (A) New positive SARS-CoV-2 RT-PCR cases by day, annotated with key dates and events of relevance for this study. Data from Scottish Government. (B) Date ranges for key social distancing measures in Scotland during the lockdown period.

Figure 2

Unscheduled primary care and emergency department (ED) attendances for Scottish children during/after lockdown. (A) Out-of-hours (OOH) unscheduled primary care consultations. Number of unscheduled primary care consultations by epidemiological week compared with mean number of consultations, with 95% CIs, for 2016–2019. Data shown from a total of 273 455 consultations (including telephone consultations). (B) ED attendances. Data shown as for (A) for a total of 462 437 attendances. (C) Emergency medical paediatric admissions. Number of emergency medical paediatric admissions in 2020, compared with admissions in 2018 and 2019. Data shown for a total of 51 596 admissions. (D) Emergency surgical paediatric admissions. Data presented as in (C) for a total of 2480 admissions. All data in (A)–(D) normalised by population at risk per year. (E) Proportion of hospital admissions to ED attendances.

Figure 3

Paediatric intensive care unit (PICU) admissions for Scottish children. (A) The overall number of emergency admissions to PICU requiring invasive mechanical ventilation in March to June 2020 fell when compared with the mean for previous years. Geometric mean and 95% CIs shown for 2016–2019, expressed as number of admissions per 100 000 children at risk. Data shown for a total of 413 admissions during the study period. (B) The reduction in admissions was most marked for diseases of the respiratory system. Geometric mean and 95% CIs shown for five most common International Classification of Diseases 11th Revision (ICD-11) chapters. There was a reduction in overall admissions for respiratory causes (77% reduction), and no change in admissions for injury, poisoning or other external causes. P values calculated from z-scores for 2020 compared with means and SD for 2016–2019. (C) A reduction in admissions was not associated with an increase in severity scores on arrival in the PICU. Median and IQRs shown for log₁₀ Paediatric Index of Mortality-2 Recalibrated (PIM2R) scores on admission for admissions between 23 March and 30 June 2020 compared with the equivalent period in 2016–2019. Distributions compared using a Kolmogorov-Smirnov test, p=0.23.

Figure 4

Childhood mortality during lockdown study period in Scotland. (A) There was no significant change in child mortality in the lockdown study period compared with the equivalent period in previous years. Number of deaths per 100 000 children in Scotland in epidemiological weeks 13–30 for 2020, compared with the 2016–2019. Horizontal lines show means with 95% CIs for years 2016–2019. P values calculated from z-scores for 2020 compared with means and SD for 2016–2020. (B) Childhood deaths by cause in 2020 compared with previous years. Deaths per 100 000 children classified by International Classification of Diseases 10th Revision (ICD-10) chapter. A number of deaths for 2019 and 2020 have not yet been classified by ICD-10 code and fall into the ‘Not yet classified’ group.