The association between severe asthma exacerbations and incident acute respiratory infection (ARI) and was similar for COVID-19 and other ARIs, both before and after the emergence of the Omicron variant, according to study findings published in the journal Thorax.
Researchers sought to determine the relationship between asthma exacerbations, ARIs (both COVID-19 and non-COVID-19-related ARIs), the use of face coverings, and in-person social mixing, through analysis of data collected while COVID-19 pandemic restrictions were fully in force as well as when those restrictions began to relax.
The analysis involved 2312 adults with asthma who had taken part in COVIDENCE UK, a longitudinal clinical trial (ClinicalTrials.gov identifier: NCT04330599), conducted between May 1, 2020, and October 6, 2021. COVIDENCE UK, a population-based study of UK residents, employed a national media campaign to invite people to complete a detailed online baseline questionnaire that captured self-reported information associated with their sociodemographic characteristics, occupation, quality of life, lifestyle, height, weight, medical conditions, vaccination status, medication use, and dietary and supplemental micronutrient intake. Monthly follow-up questionnaires subsequently collected data regarding: (1) behaviors that possibly influenced respondents’ risk for acquisition or transmission of ARIs; (2) incident ARI symptoms; (3) results of reverse transcription polymerase chain reaction and antigen testing for respiratory viruses; (4) incident exacerbations of asthma and chronic obstructive pulmonary disease; and (5) participants’ total number of SARS-CoV-2 vaccine doses.
The current asthma-related analysis included only COVIDENCE UK participants with asthma who (1) reported using at least 1 prescribed asthma treatment and/or having at least 1 severe asthma exacerbation in the 12 months prior to enrollment; (2) completed at least 1 COVIDENCE UK monthly follow-up questionnaire; and (3) completed at least 1 monthly follow-up questionnaire between November 12, 2020, and April 21, 2022, after the conclusion of COVIDENCE UK.
Results of the analysis showed that the relaxation in COVID-19 restrictions beginning in April 2021 coincided with a significant reduction in the use of face coverings (P <.001) and a significant increase in the frequency of indoor visits to public places and other households (P <.001), along with a significant rise in the incidence of COVID-19 (P <.001), non-COVID-19 ARIs (P <.001), and severe asthma exacerbations (P =.007).
Incident non-COVID-19 ARI was associated with an increased likelihood of reporting an asthma exacerbation, following adjustment for multiple potential confounders (adjusted odds ratio [aOR], 5.75; 95% CI, 4.75-6.97). In a similar fashion, incident COVID-19 was associated with increased odds of severe asthma exacerbations — both prior to the dominance of the Omicron SARS-CoV-2 variant in December 2021 (aOR, 5.89; 95% CI, 3.45-10.04) and subsequently (aOR, 5.69; 95% CI, 3.89-8.31).In conclusion, this large prospective population-based study shows for the first time that relaxation of COVID-19 restrictions in the UK coincided with increased risk of COVID-19 and non-COVID-19 ARI, which in turn associated independently with increased risk of severe asthma exacerbations.
Several limitations of the current study should be noted. Because no asthma outcomes data were obtained before November 2020, information prior to the pandemic and its early phases is thus lacking. Further, temporal associations among trends in behaviors, infections, and asthma exacerbations should not necessarily be interpreted as being causal, based on the observational design of the current study.
“In conclusion, this large prospective population-based study shows for the first time that relaxation of COVID-19 restrictions in the UK coincided with increased risk of COVID-19 and non-COVID-19 ARI, which in turn associated independently with increased risk of severe asthma exacerbations,” said study authors.
Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Tydeman F, Pfeffer PE, Vivaldi G, et al. Rebound in asthma exacerbations following relaxation of COVID-19 restrictions: a longitudinal population-based study (COVIDENCE UK). Thorax. Published online November 23, 2022. doi:10.1136/thorax-2022-219591