Background: The prevalence of depression in celiac disease (CD) is high, and patients are often burdened socially and financially by a gluten-free diet. However, the relationship between depression, somatic symptoms and dietary adherence in CD is complex and poorly understood. We used a patient powered research network (iCureCeliac^®) to explore the effect that depression has on patients’ symptomatic response to a gluten-free diet (GFD). Methods: We identified patients with biopsy-diagnosed celiac disease who answered questions pertaining to symptoms (Celiac Symptom Index (CSI)), GFD adherence (Celiac Dietary Adherence Test (CDAT)), and a 5-point, scaled question regarding depressive symptoms relating to patients’ celiac disease. We then measured the correlation between symptoms and adherence (CSI vs. CDAT) in patients with depression versus those without depression. We also tested for interaction of depression with regard to the association with symptoms using a multiple linear regression model. Results: Among 519 patients, 86% were female and the mean age was 40.9 years. 46% of patients indicated that they felt “somewhat,” “quite a bit,” or “very much” depressed because of their disorder. There was a moderate correlation between worsened celiac symptoms and poorer GFD adherence (r = 0.6, p < 0.0001). In those with a positive depression screen, there was a moderate correlation between worsening symptoms and worsening dietary adherence (r = 0.5, p < 0.0001) whereas in those without depression, the correlation was stronger (r = 0.64, p < 0.0001). We performed a linear regression analysis, which suggests that the relationship between CSI and CDAT is modified by depression. Conclusions: In patients with depressive symptoms related to their disorder, correlation between adherence and symptoms was weaker than those without depressive symptoms. This finding was confirmed with a linear regression analysis, showing that depressive symptoms may modify the effect of a GFD on celiac symptoms. Depressive symptoms may therefore mask the relationship between inadvertent gluten exposure and symptoms. Additional longitudinal and prospective studies are needed to further explore this potentially important finding.

Background and Aims: Patients with celiac disease (CD) commonly use supplements for perceived health benefits despite scant evidence. We aimed to characterize the prevalence and predictors of probiotic use among CD patients. Methods: We analyzed data from iCureCeliac®; a patient-powered research network questionnaire distributed by the Celiac Disease Foundation. We included adults with self-reported CD who answered questions regarding demographics, diagnosis, symptoms, and treatment. We compared probiotic users versus probiotic non-users and subsequently performed multivariable logistic regression, assessing for independent predictors of probiotic use. Results: 4,909 patients met the criteria for inclusion in the study. Of these, 1,160 (23.6%) responded to a question regarding probiotic use. The mean age of participants was 38.8 years and 82% were female. 381 patients (33%) reported using probiotics. More probiotic users sought nutritional counseling at time of diagnosis (36% vs. 30%, p=0.05) and remained symptomatic despite a gluten-free diet (40% vs. 25%, p <0.001). Probiotic users had lower scores on the pain subscale of the SF36 (63.7±21.6 vs. 69.5±22.1, p=0.006). On multivariable analysis, patients diagnosed after age 50 (OR=2.04, 95%CI: 1.37-3.04), and those with persistent symptoms despite a gluten-free diet (OR=1.94, 95%CI: 1.44-2.63) were more likely to use probiotics. Conclusion: In this large study of a national CD registry, roughly one-third of CD patients reported using probiotics. Patients diagnosed later in life were more likely to use probiotics and those who remained symptomatic despite a gluten-free diet were twice as likely to take probiotics. Patients may be seeking additional means of treatment for persistent symptoms.