Association between Aphthous/Intraoral Ulcers and Body Mass Index

Recurrent aphthous stomatitis (RAS) is characterized by cyclic ulcers (aphthae or canker sores) of unknown etiology. Body mass index (BMI; Kg/m2) is a reliable indicator of body fat in most people. Although clinically many RAS patients appear to be thin, the association between RAS and BMI has not been explored.

Objectives: We hypothesize that aphthae/intraoral ulcers (IOU) and body mass index are associated.

Methods: We performed secondary statistical analyses of National Health and Nutrition Examination Survey III (NHANES III). Participants were asked if they had a history of IOU in the past 12 months (yes/no) and underwent body mass measurements (height and weight). We analyzed data separately from young (n=12,134; aged 8-39) and old (n=9,658; aged 40 and over) participants using PROC RLOGIST in SUDAAN v9.01.

Results: Fourteen percent of young and 9% of old participants reported a history of IOU. Young IOU participants had lower BMI than controls. The OR (95% CI) of having had an IOU in the past 12 months vs. not having had IOU were 1.25 (1.04-1.50) for every 10-unit decrease in BMI, after controlling for age, race/ethnicity and gender. The association weakened in participants 40 years and older (adjusted OR, 95%CI = 1.14, 0.96-1.37).

Conclusion: These results suggest a possible link between factors associated with energy homeostasis and predisposing factors for RAS. This association is only apparent in young adults. Although reduced food intake due to the presence of long-lasting painful aphthae may explain in part a lower BMI in patients with major RAS, transient pain in the majority of patients with minor RAS may not be the primary reason for the BMI differential. Further research is needed to confirm these findings and establish the exact underlying reasons for this association.