The Incidence and Severity of COVID-19 in the Liverpool Severe Asthma Population Undergoing Biologic Therapy

Background The coronavirus disease 2019 (COVID-19) infection can have a variable impact on patients. Various host factors have been identified that play a significant role in the risk of COVID-19 infection and its severity. Patients with severe asthma have been clinically vulnerable since the first wave of the pandemic and the resurgence of COVID-19 in the United Kingdom in January 2020. In addition, those on treatment with monoclonal antibodies (mAbs) have been identified as being vulnerable to COVID-19 infection and severity by the World Health Organization and the Department of Health. However, the evidence to support this notion is limited, and there has been contrary evidence to suggest severe asthma is protective against COVID-19. In this study, a retrospective review of severe asthma patients in the Liverpool population between 1st January 2020 and 31st January 2021 was conducted. This study aimed to determine the association between asthma severity and the risk of COVID-19 infection and/or its severity for patients on mAb treatment. Methodology We conducted a review of all patients from the Liverpool severe asthma database/spreadsheet who tested positive in the community and at the hospital. Admission records, primary records, emails, and microbiological data for Anglia ICE were reviewed at the Royal Liverpool and Aintree University Hospital. A COVID-19 diagnosis was predefined as a positive lateral flow test and a positive polymerase chain reaction test. The proportion of patients with COVID-19 pneumonia and severe COVID-19 disease requiring hospital admission and escalation to intensive care (observation, intubation, continuous positive airway pressure) was noted. Other patient characteristics were recorded including age, weight, body mass index (BMI), gender, smoking status (never, former, current smoker), bronchiectasis, and the forced expiratory volume. Results In total, 760 patients were identified to have severe asthma, of whom 59 (7.8%) tested positive for COVID-19 and 701 (92.2%) tested negative. A total of 244 (32%) patients were taking mAbs, and 516 (68%) were not on mAb treatment. Patients were more susceptible to COVID-19 on an mAb (13.5%) versus non-mAb (5%) (odds ratio (OR) = 2.95; 95% confidence interval (CI) = 1.72 to 5.05) . A larger proportion of severe asthma patients on mAb treatment testing positive for COVID-19 were current smokers and had a higher BMI. Furthermore, severe asthmatics taking mAbs did not have a higher risk of severe COVID-19 disease, hospitalisation, and intensive care admission. Conclusions In the Liverpool severe asthma population, patients undergoing mAb therapy had a higher incidence of COVID-19 compared to non-mAb groups; however, they were not at a higher risk of severe disease progression. These findings suggest that continuing biologic therapy in severe asthmatics with COVID-19 appears to be safe to prevent exacerbations.