Adults with asthma had, at one point, an approximately doubled risk of a severe asthma attack after COVID-19 restrictions were relaxed in the UK, according to new research from Queen Mary University of London.

Episodes of progressive worsening of asthma symptoms, termed exacerbations or asthma attacks, are the major cause of illness and death in this condition. Asthma affects more than 5 million people in the UK and more than 300 million globally. Symptoms include breathlessness and chest tightness as well as wheezing and coughing.

Published in Thorax and presented at today’s British Thoracic Society meeting, the research found an increased risk of these attacks after COVID-19 restrictions were relaxed. When restrictions were lifted, fewer people wore face coverings and there was more social mixing, and subsequently a higher risk of COVID-19 and other acute respiratory infections. The research also found that COVID-19 was not significantly more likely to trigger asthma attacks than other respiratory infections.

In April 2021, when authorities began to relax social mixing restrictions and the need for face coverings, 1.7 percent of participants reported having had a severe asthma attack in the previous month. In January 2022, this proportion more than doubled, going up to 3.7 percent.

The study analyzed data from 2,312 UK adults with asthma, participating in Queen Mary’s COVIDENCE UK study between November 2020 and April 2022. Details on face covering use, social mixing, and asthma symptoms were collected via monthly online questionnaires.

Professor Adrian Martineau, lead author of the research and Clinical Professor of Respiratory Infection and Immunity at Queen Mary University of London, said, “This research shows that relaxation of COVID-19 restrictions coincided with an increased risk of severe asthma attacks. Our study was observational, so it can’t prove cause and effect. But our findings do raise the possibility that certain elements of the public health measures introduced during the pandemic—such as wearing face masks—could help in reducing respiratory illnesses moving forward.”

Dr. Florence Tydeman, first author on the paper, added, “It is also reassuring to see that COVID-19 was not significantly more likely to trigger asthma attacks than other respiratory infections in our study participants.”

The study is the first to compare the influence of COVID-19 to that of other respiratory infections on the risk of asthma exacerbations. It is also one of few studies that looks at the impact on people with asthma of lifting national restrictions.