The Association between Allergic Rhinitis and COVID-19: A Systematic Review and Meta-Analysis.

Objective: Previous studies have yielded conflicting results regarding the association of coronavirus disease 2019 (COVID-19) with allergic rhinitis (AR). Data on AR prevalence in COVID-19 patients are limited. Consequently, whether AR is a harmful or protective factor for COVID-19 patients remains controversial. Therefore, we analyzed the relationship between COVID-19 and AR. Methods: We systematically searched PubMed, Embase, Cochrane, and Web of Science databases for studies published between January 1, 2020 and January 11, 2022. We included studies reporting the epidemiological and clinical characteristics of COVID-19 and its incidence in patients with AR. We excluded letters, case reports, literature review articles, non-English language article, and non-full-text articles. The raw data from these studies were pooled into a meta-analysis. Results: We analyzed the results of nine studies. The prevalence of AR in patients with COVID-19 was 0.13 (95% confidence interval [CI] 0.04-0.25), with an overall I 2 of 99.77%, P=0.24. COVID-19 patients with AR are less prone to severe disease (odds ratio [OR] = 0.79, 95% CI, 0.52-1.18, P=0.25) and hospitalization (OR = 0.23, 95%CI, 0.02-2.67, P ≤ 0.0001) than patients without AR. Conclusion: Our data suggest that allergic rhinitis is a protective factor in patients with COVID-19.

Asthma does not influence the severity of COVID-19: a meta-analysis.

OBJECTIVE: Previous studies have reported a correlation between coronavirus disease-2019 (COVID-19) and asthma. However, data on whether asthma constitutes a risk factor for COVID-19 and the prevalence of asthma in COVID-19 cases still remain scant. Here, we interrogated and analyzed the association between COVID-19 and asthma. METHODS: In this study, we systematically searched PubMed, Embase, and Web of Science databases for studies published between January 1 and August 28, 2020. We included studies that reported the epidemiological and clinical features of COVID-19 and its prevalence in asthma patients. We excluded reviews, animal trials, single case reports, small case series and studies evaluating other coronavirus-related illnesses. Raw data from the studies were pooled into a meta-analysis. RESULTS: We analyzed findings from 18 studies, including asthma patients with COVID-19. The pooled prevalence of asthma in COVID-19 cases was 0.08 (95% CI, 0.06-0.11), with an overall I2 of 99.07%, p < 0.005. The data indicated that asthma did not increase the risk of developing severe COVID-19 (odds ratio [OR] 1.04 (95% CI, 0.75-1.46) p = 0.28; I2=20%). In addition, there was no significant difference in the incidence of asthma with age in COVID-19 infections [OR] 0.77(95% CI, 0.59-1.00) p = 0.24; I2=29%). CONCLUSION: Taken together, our data suggested that asthma is not a significant risk factor for the development of severe COVID-19.