Epidemiology of Celiac Disease

Celiac disease (CD) is characterized by changes in duodenal and small bowel mucosa that are caused by gluten intolerance. These changes include an increase in intra-epithelial lymphocytes, partial or complete villous atrophy, and hypoplasia of the small bowel architecture. CD usually responds to a gluten-free diet (GFD). In epidemiologic studies CD is often diagnosed serologically with positive anti-enomysium and/or anti-tissue transglutaminase antibodies. CD is found in most populations but is commonest in those of Northern European origin with a prevalence of approximately 1%. There is a strong genetic susceptibility with almost universal association with HLA class II DQ2 or DQ8 haplotypes. Classically CD presents with diarrhea and malabsorption but it is increasingly recognized that the presentation can be atypical with vague abdominal complaints, fatigue, arthralgia, or abnormal laboratory tests such as iron deficiency anemia. Patients with undiagnosed CD have a lower quality of life than the general population and possibly an increased all-cause mortality. It is therefore important for the clinician to have a low threshold for screening for CD with serology. Further studies are needed to better define the risk of undiagnosed CD and whether a GFD ameliorates this risk. Studies evaluating the impact and cost-effectiveness of population screening for CD are also required.