Symptoms of Functional Intestinal Disorders Are Common in Patients with Celiac Disease Following Transition to a Gluten-Free Diet

Celiac disease and functional intestinal disorders may overlap, yet the natural history of functional symptoms in patients with celiac disease is unknown. To investigate the prevalence of irritable bowel syndrome (IBS), functional dyspepsia (FD), and functional bloating (FB) symptoms among patients with celiac disease at diagnosis and during the first year of a gluten-free diet. Adults with a new diagnosis of celiac disease were surveyed at baseline, 6 months and 1 year using standardized measures for intestinal symptoms [Rome III diagnostic questionnaire and celiac symptom index (CSI)] and gluten-free diet adherence [gluten-free eating assessment tool (GF-EAT) and celiac diet adherence test]. At diagnosis, two-thirds fulfilled Rome III diagnostic questionnaire symptom criteria for IBS (52%), functional dyspepsia (27%), and/or functional bloating (9%). One year post-diagnosis, there was high adherence to a gluten-free diet as 93% reported gluten exposure less than once per month on the GF-EAT and only 8% had ongoing celiac disease symptoms (CSI score > 45). The rates of those meeting IBS (22%) and functional dyspepsia (8%) symptom criteria both decreased significantly on a gluten-free diet. The prevalence of functional symptoms (any of IBS, FD or FB) at 1 year was 47%. Long-term follow-up of patients with celiac disease is necessary because many patients with celiac disease who are adherent to a gluten-free diet have persistent gastrointestinal symptoms.