Asthma and COVID-19 risk: a systematic review and meta-analysis

Abstract

BackgroundIndividual case series and cohort studies have reported conflicting results on the vulnerability to and risk of mortality of people with asthma from COVID-19.Research QuestionAre people with asthma at a higher risk of being infected, hospitalised or of poorer clinical outcomes from COVID-19?MethodsA systematic review and meta-analysis based on five main databases including the WHO COVID-19 database between December 1, 2019 to July 11, 2021 on studies with a control (non-asthma) group was conducted. Prevalence and risk ratios were pooled using Sidik-Jonkman random effects meta-analyses.FindingsFifty-one 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 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.InterpretationThe risk of being infected with SARS-CoV-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.

Impact of asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap on the prognosis of coronavirus disease 2019

“…This suggests that prompt diagnosis and effective preparation for oxygen demand may affect patient mortality when treating patients with COVID-19 and chronic obstructive airway diseases. Several studies have shown that asthma has no effect on the severity of COVID-19, and that ACO and COPD seem to be increased the mortality and morbidity of COVID-19 [ 21 22 23 ]. Nonetheless, the CDC still reports that “severe asthma” is associated with the severity of COVID-19.…”

Impact of asthma on COVID-19 mortality in the United States: Evidence based on a meta-analysis

“…Previous meta-analyses have investigated the association between asthma and COVID-19 mortality in the whole regions [1] , [2] , [3] , but the conclusions were inconsistent, which might suffer limitations from substantial variation of asthma prevalence among different countries. Moreover, a previous meta-analysis by Sunjaya et al reported that COVID-19 patients with asthma had a significantly increased risk for mortality in Asia, but not in Europe, North America and South America [4] . Taken together, those urged us to investigate the association between asthma and COVID-19 mortality in a specific country or region.…”

Insights into potential mechanisms of asthma patients with COVID-19: A study based on the gene expression profiling of bronchoalveolar lavage fluid

“…Thus, the restrictions imposed by COVID‐19 pandemic have severely affected the management of asthma. According to the results of the two systematic reviews, the risk of SARS-CoV-2 infection and mortality after infection for asthma sufferers are reduced compared with non-asthma patients [ 33 , 34 ]. However, a Korean cohort study shows that the incidence of asthma is related to the severity and mortality of COVID-19 [ 7 ].…”