Risk of Severe Covid-19 in Patients with Celiac Disease: A Population-Based Cohort Study

Background: Patients with celiac disease (CeD) are at increased risk of certain viral infections and of pneumococcal pneumonia, raising concerns that they may be susceptible to severe coronavirus disease 2019 (Covid-19). We aimed to quantify the association between CeD and severe outcomes related to Covid-19. Methods: We performed a population-based cohort study, identifying individuals with CeD in Sweden, as defined by small intestinal villus atrophy diagnosed at all (n=28) Swedish pathology departments during the years spanning 1969-2017, and alive on February 1, 2020. We compared these patients to controls matched by sex, age, county, and calendar period. We performed Cox proportional hazards with follow-up through July 31, 2020, assessing risk of 1) hospital admission with a primary diagnosis of laboratory-confirmed Covid-19 (co-primary outcome); and 2) severe disease as defined by admission to intensive care unit and/or death attributed to Covid-19 (co-primary outcome). Results: Among patients with CeD (n=40,963) and controls (n=183,892), the risk of hospital admission for Covid-19 was 2.9 and 2.2 per 1000 person-years respectively. After adjusting for comorbidities, the risk of hospitalization for Covid-19 was not significantly increased in patients with CeD (HR 1.10; 95% CI 0.80-1.50), nor was the risk of severe Covid-19 increased (HR 0.97; 95% CI 0.59-1.59). Results were similarly null when we compared CeD patients to their non-CeD siblings with regard to these outcomes. Among all patients with CeD and controls hospitalized with a diagnosis of Covid-19 (n=58 and n=202, respectively), there was no significant difference in mortality (HR for CeD compared to controls 0.96; 95% CI 0.46-2.02). Conclusion: In this population-based study, CeD was not associated with an increased risk of hospitalization for Covid-19 or intensive care unit and/or death attributed to Covid-19.