Celiac Disease and the Susceptibility of COVID-19 and the Risk of Severe COVID-19: A Mendelian Randomization Study

Abstract

INTRODUCTION:Previous observational studies have found that the susceptibility of coronavirus disease 2019 (COVID-19) and the risk of severe COVID-19 are not increased in patients with celiac disease (CeD). However, the findings of observational studies are prone to bias due to reverse causation and confounding factors, especially in the case of a newly emerged disease. In this study, we aimed to further clarify the underlying relationship by both observational and Mendelian randomization (MR) analysis.METHODS:This observational study was conducted in the UK Biobank cohort. Univariate and multivariate logistic regression analyses were performed to identify the risk factors of COVID-19 susceptibility and severe COVID-19. To understand the causality between CeD and COVID-19 susceptibility and severe COVID-19, we performed a 2-sample MR analysis.RESULTS:Our observational study showed that patients with CeD had a lower susceptibility of COVID-19 (odds ratio [OR] = 0.699, P = 0.006) while CeD was not significantly associated with severe COVID-19 (P > 0.05). The findings from our MR study further demonstrated that both the susceptibility to COVID-19 (OR = 0.963, P = 0.006) and severe COVID-19 (OR = 0.919, P = 0.049) were lower in patients with CeD, although the former seemed to be specific to the UK Biobank cohort.DISCUSSION:Our results suggested that it may be unnecessary to take extra COVID-19 precaution in patients with CeD.

Prevalence and clinical outcomes of COVID‐19 in patients with pre‐existing celiac disease: A systematic review and meta‐analysis

“…930 articles were further excluded after considering the title and abstract, generating 68 papers for satisfactory article review for plausible consideration in this analysis. Eventually, 11 articles consisting of 44,378 celiac patients were incorporated into this meta‐analysis based on exhaustive evaluation and inclusion criteria 8,14–23 . The baseline characteristics of the incorporated studies are summarised in Table 1.…”

“…Eventually, 11 articles consisting of 44,378 celiac patients were incorporated into this meta-analysis based on exhaustive evaluation and inclusion criteria. 8,[14][15][16][17][18][19][20][21][22][23] The baseline characteristics of the incorporated studies are summarised in Table 1. Four of these included studies were from Italy, followed by the USA with two reports and one from Iran, Sweden, and the United Kingdom.…”

COVID-19 and the gastrointestinal tract in children

“…Lastly, observational studies examined the risk of severe COVID-19 and mortality in patients with celiac disease. These studies were not specific to pediatrics, but overall, they did not find an increased risk of severe COVID-19 in individuals with celiac disease and compliant with a gluten-free diet [27 ▪ ,29].…”

“…During the COVID-19 pandemic, studies explored SARS-CoV-2 as a potential trigger for different autoimmune conditions. Although type 1 diabetes became more frequently diagnosed [25 ▪ ], studies failed to demonstrate an increased incidence of celiac disease during the pandemic [26,27 ▪ ]. It is unclear if this was the result of the increased hygienic measures leading to decreased exposure to SARS-COV-2 and other viruses typically associated with an increased risk of developing celiac disease such as enteroviruses, adenoviruses, and rotaviruses.…”

Coronavirus disease 2019 and gastrointestinal disorders in children

“…83 Also adult studies have unequivocally shown a similar incidence of COVID-19 in CeD as in the general journals.sagepub.com/home/tag TherapeuTic advances in Gastroenterology population. [84][85][86] Likewise, a large US study (TriNETX) found no significantly increased risk of hospital admission, critical care, or death from COVID-19. 87…”