PT - JOURNAL ARTICLE AU - Syed A Shah AU - Jennifer K Quint AU - Bright I Nwaru AU - Aziz Sheikh TI - Impact of COVID-19 national lockdown on asthma exacerbations: interrupted time-series analysis of English primary care data AID - 10.1136/thoraxjnl-2020-216512 DP - 2021 Sep 01 TA - Thorax PG - 860--866 VI - 76 IP - 9 4099 - http://thorax.bmj.com/content/76/9/860.short 4100 - http://thorax.bmj.com/content/76/9/860.full SO - Thorax2021 Sep 01; 76 AB - Background The impact of COVID-19 and ensuing national lockdown on asthma exacerbations is unclear.Methods We conducted an interrupted time-series (lockdown on 23 March 2020 as point of interruption) analysis in asthma cohort identified using a validated algorithm from a national-level primary care database, the Optimum Patient Care Database. We derived asthma exacerbation rates for every week and compared exacerbation rates in the period: January to August 2020 with a pre-COVID-19 period and January to August 2016–2019. Exacerbations were defined as asthma-related hospital attendance/admission (including accident and emergency visit), or an acute course of oral corticosteroids with evidence of respiratory review, as recorded in primary care. We used a generalised least squares modelling approach and stratified the analyses by age, sex, English region and healthcare setting.Results From a database of 9 949 387 patients, there were 100 165 patients with asthma who experienced at least one exacerbation during 2016–2020. Of 278 996 exacerbation episodes, 49 938 (17.9%) required hospital visit. Comparing pre-lockdown to post-lockdown period, we observed a statistically significant reduction in the level (−0.196 episodes per person-year; p<0.001; almost 20 episodes for every 100 patients with asthma per year) of exacerbation rates across all patients. The reductions in level in stratified analyses were: 0.005–0.244 (healthcare setting, only those without hospital attendance/admission were significant), 0.210–0.277 (sex), 0.159–0.367 (age), 0.068–0.590 (region).Conclusions There has been a significant reduction in attendance to primary care for asthma exacerbations during the pandemic. This reduction was observed in all age groups, both sexes and across most regions in England.Data may be obtained from a third party and are not publicly available. The dataset for this work can be accessed from OPCRD (https://opcrd.co.uk/) subject to protocol approval from an independent scientific advisory committee, ADEPT (Anonymized Data Ethics and Protocol Transparency committee). The code used in the analysis in our current work will be made available at https://github.com/syedahmar/Covid19-ImpactAsthmaExacerbations under Creative Commons License.