Effects of the COVID-19 pandemic on the mental health of clinically extremely vulnerable children and children living with clinically extremely vulnerable people in Wales: A data linkage study
Authors: Cowley Laura E , Hodgson Karen , Song Jiao , Whiffen Tony , Tan Jacinta , John Ann , Bandyopadhyay Amrita , Davies Alisha R 
Published: September 2022

AbstractObjectivesTo determine whether clinically extremely vulnerable (CEV) children or children living with a CEV person in Wales were at greater risk of presenting with anxiety or depression in primary or secondary care during the COVID-19 pandemic compared with children in the general population, and to compare patterns of anxiety and depression during the pandemic (23rd March 2020–31st January 2021, referred to as 2020/21) and before the pandemic (March 23rd 2019–January 31st 2020, referred to as 2019/20), between CEV children and the general population.DesignPopulation-based cross-sectional cohort study using anonymised, linked, routinely collected health and administrative data held in the Secure Anonymised Information Linkage Databank. CEV individuals were identified using the COVID-19 Shielded Patient List.SettingPrimary and secondary healthcare settings covering 80% of the population of Wales.ParticipantsChildren aged 2–17 in Wales: CEV (3,769); living with a CEV person (20,033); or neither (415,009).Primary outcome measureFirst record of anxiety or depression in primary or secondary healthcare in 2019/20 and 2020/21, identified using Read and ICD-10 codes.ResultsA Cox regression model adjusted for demographics and history of anxiety or depression revealed that only CEV children were at greater risk of presenting with anxiety or depression during the pandemic compared with the general population (Hazard Ratio=2.27, 95% Confidence Interval=1.94–2.66, p<0.001). Compared with the general population, the risk amongst CEV children was higher in 2020/21 (Risk Ratio 3.04) compared with 2019/20 (Risk Ratio 1.90). In 2020/21, the cumulative incidence of anxiety or depression increased slightly amongst CEV children, but declined amongst the general population.ConclusionsDifferences in the cumulative incidences of recorded anxiety or depression in healthcare between CEV children and the general population were largely driven by a reduction in presentations to healthcare services by children in the general population during the pandemic.Strengths and limitations of this studyStrengths of this study include its novelty, national focus and clinical relevance; to date this is the first population-based study examining the effects of the COVID-19 pandemic on healthcare use for anxiety or depression amongst clinically extremely vulnerable (CEV) children and children living with a CEV person in WalesWe compared 2020/21 data with pre-pandemic 2019/20 data for CEV children and children in the general population, to place the impact of the COVID-19 pandemic in the context of longer-term patterns of healthcare useWe used a novel approach and linked multiple datasets to identify a cohort of children living with a CEV person in Wales during the COVID-19 pandemicThere was heterogeneity within the Shielded Patient List that was used to create the cohorts of children identified as CEV or living with a CEV person, in terms of the type and severity of individuals’ underlying conditions; the manner in which people were added to the list; the time point that people were added to the list; and the extent to which people followed the shielding guidanceRoutinely collected healthcare data does not capture self-reported health, and is likely to underestimate the burden of common mental disorders in the population