Introduction The imposition of COVID-19 restrictions in Spring 2020 was followed by a drop in asthma exacerbations in the UK.¹ Temporal trends in asthma exacerbations following relaxation of these restrictions have not yet been described.

Objectives To describe temporal trends in use of face coverings, social mixing, incidence of acute respiratory infections (ARI) and risk of exacerbations in a UK cohort of adults with asthma between November 2020 and April 2022.

Methods Participants (n=2740) were adult UK residents with doctor-diagnosed asthma who took part in a national population-based longitudinal study of COVID-19 (COVIDENCE UK). Details of face covering use, social mixing, and incidence of RT-PCR- or antigen test-confirmed COVID-19, non-COVID ARI (RT-PCR- or antigen test-negative for SARS-CoV-2) and moderate/severe asthma exacerbations (i.e. those requiring treatment with systemic corticosteroids and/or hospitalisation) were collected via monthly on-line questionnaires. Changes in these parameters over time were visualised using generalised additive models. Multivariate mixed logistic regression was used to calculate adjusted odds ratios (aOR) for associations between incident ARI and risk of asthma exacerbations, adjusting for age, sex, ethnicity, sociodemographic factors, self-rated health, asthma severity and asthma exacerbation history prior to enrolment.

Results COVID-19 restrictions were relaxed between April and December 2021. This period coincided with reduced use of face coverings (p<0.001), increased frequency of indoor visits to public places and other households (p<0.001) and rising incidence of COVID-19 (p<0.001), non-COVID ARI (p<0.001) and asthma exacerbations (p=0.006; figure 1). After adjustment for multiple potential confounders, incident non-COVID ARI associated with an increased risk of asthma exacerbation (aOR 7.04, 95% CI 5.73 to 8.65), as did incident COVID-19, both prior to emergence of the omicron variant of SARS-CoV-2 in December 2021 (aOR 5.56, 95% CI 2.85 to 10.81) and subsequently (aOR 6.73, 95% CI 4.59 to 9.85).

• Download figure
• Open in new tab
• Download powerpoint

Abstract P80 Figure 1

Generalised additive models showing trends in behaviours and acute respiratory infections (ARI) from November 2020 to April 2022 in UK adults with asthma. A, visits to indoor public places. B, visits to other households. C, use of face coverings. D, RT-PCR or antigen test-confirmed COVID-19. E, ARI testing negative for SARS-CoV-2 by RT-PCR or antigen test. F, asthma exacerbations requiring treatment with systemic corticosteroids and/or hospitalisation. Dotted lines show 95% confidence intervals

Conclusions Relaxation of COVID-19 restrictions coincided with decreased use of face coverings, increased social mixing and a rebound in ARI and asthma exacerbations. Associations between incident ARI and risk of exacerbation were similar for non-COVID ARI and COVID-19, both before and after emergence of the omicron variant of SARS-CoV-2.

Reference

1. Thorax, 2021. 76(9): p. 867–873.

ReferencePlease refer to page A214 for declarations of interest related to this abstract.