ABSTRACT
BACKGROUND: Individual case series and cohort studies have reported conflicting results in people with asthma on the vulnerability to and risk of mortality from coronavirus disease 2019 (COVID-19). RESEARCH QUESTION: Are people with asthma at a higher risk of being infected or hospitalised or poorer clinical outcomes from COVID-19? METHODS: A systematic review and meta-analysis based on five main databases including the World Health Organization COVID-19 database between 1 December 2019 and 11 July 2021 on studies with a control (non-asthma) group was conducted. Prevalence and risk ratios were pooled using Sidik-Jonkman random-effects meta-analyses. FINDINGS: 51 studies with an 8.08% (95% CI 6.87-9.30%) pooled prevalence of people with asthma among COVID-19 positive cases. The risk ratios were 0.83 (95% CI 0.73-0.95, p=0.01) for acquiring COVID-19; 1.18 (95% CI 0.98-1.42, p=0.08) for hospitalisation; 1.21 (95% CI 0.97-1.51, p=0.09) for intensive care unit (ICU) admission; 1.06 (95% CI 0.82-1.36, p=0.65) for ventilator use; and 0.94 (95% CI 0.76-1.17, p=0.58) for mortality for people with asthma. Subgroup analyses by continent revealed a significant difference in risk of acquiring COVID-19, ICU admission, ventilator use and death between the continents. INTERPRETATION: The risk of being infected with severe acute respiratory syndrome coronavirus 2 was reduced compared to the non-asthma group. No statistically significant differences in hospitalisation, ICU admission and ventilator use were found between groups. Subgroup analyses showed significant differences in outcomes from COVID-19 between America, Europe and Asia. Additional studies are required to confirm this risk profile, particularly in Africa and South America, where few studies originate.
Subject(s)
Asthma , COVID-19 , Asthma/epidemiology , Hospitalization , Humans , Intensive Care Units , SARS-CoV-2ABSTRACT
OBJECTIVE: As COVID-19 spreads across the world, there are concerns that people with asthma are at a higher risk of acquiring the disease, or of poorer outcomes. This systematic review aimed to summarize evidence on the risk of infection, severe illness and death from COVID-19 in people with asthma. DATA SOURCES AND STUDY SELECTION: A comprehensive search of electronic databases including preprint repositories and WHO COVID-19 database was conducted (until 26 May 2020). Studies reporting COVID-19 in people with asthma were included. For binary outcomes, we performed Sidik-Jonkman random effects meta-analysis. We explored quantitative heterogeneity by subgroup analyses, meta regression and evaluating the I2 statistic. RESULTS: Fifty-seven studies with an overall sample size of 587 280 were included. The prevalence of asthma among those infected with COVID-19 was 7.46% (95% CI = 6.25-8.67). Non-severe asthma was more common than severe asthma (9.61% vs. 4.13%). Pooled analysis showed a 14% risk ratio reduction in acquiring COVID-19 (95% CI = 0.80-0.94; p < 0.0001) and 13% reduction in hospitalization with COVID-19 (95% CI = 0.77-0.99, p = 0.03) for people with asthma compared with those without. There was no significant difference in the combined risk of requiring admission to ICU and/or receiving mechanical ventilation for people with asthma (RR = 0.87 95% CI = 0.94-1.37; p = 0.19) and risk of death from COVID-19 (RR = 0.87; 95% CI = 0.68-1.10; p = 0.25). CONCLUSION: The findings from this study suggest that the prevalence of people with asthma among COVID-19 patients is similar to the global prevalence of asthma. The overall findings suggest that people with asthma have a lower risk than those without asthma for acquiring COVID-19 and have similar clinical outcomes.