Increased odds ratio for COVID-19 in patients with recurrent aphthous stomatitis.

The ACE2 receptor, the binding sites for the COVID-19, is expressed abundantly in the oral cavity, raising the question of whether the mouth is a target for the virus in addition to organs such as kidneys and lungs. Recently, a flurry of individual case reports on oral manifestation of COVID-19 including ulceration, blistering lesions, and stomatitis were published. However, it is not clear whether the oral presentations that are not unique to the virus are indeed related to the virus and appear at a higher prevalence than in the general population. We used the i2b2 platform of hospital patient's registry to determine the odds ratio for COVID-19 in patients that were diagnosed with recurrent aphthous stomatitis, an entity restricted to the oral cavity. The overall odds ratio for COVID-19 in patients with recurrent aphthous stomatitis before adjustments was 14 and after adjustment for gender, race, and age was 13.9, 6.5, and 2.93, respectively. The odds ratio remained increased after adjustments of the comorbidities such as respiratory disease, endocrine disease, obesity, diabetes, circulatory disease, and smoking and was 3.66, 7.46, 4.6, 10.54, 7.37, and 7.52, respectively. When adjusted for recurrent aphthous stomatitis, the respiratory disease had an odd ratio of 8.56 to be associated with COVID-19. African American race and age-group 18-34 were additional significant risk factors. The present study has demonstrated a significant association between COVID-19 and RAS; however, additional longitudinal and laboratory studies are necessary to establish a cause and effect relationship between these 2 conditions.