To Örebro University

OBJECTIVES: The prevalence of celiac disease (CD) varies greatly, potentially because of incomplete ascertainment of cases and small study samples with limited statistical power. Previous reports indicate that the incidence of CD is increasing. We examined the prevalence of CD in a well-defined US county. METHODS: Population-based study in Olmsted County, Minnesota, USA. Using the infrastructure of the Rochester Epidemiology Project, medical, histopathology, and CD serology records were used to identify all new cases of CD in Olmsted County since 2000. Age-and sex-specific and adjusted (to the US white 2000 population) incidence rates for CD were estimated. Clinical presentation at diagnosis was also assessed. RESULTS: Between 2000 and 2010, 249 individuals (157 female or 63%, median age 37.9 years) were diagnosed with CD in Olmsted County. The overall age-and sex-adjusted incidence of CD in the study period was 17.4 (95% confidence interval (CI) = 15.2-19.6) per 100,000 person-years, increasing from 11.1 (95 % CI = 6.8-15.5) in 2000-2001 to 17.3 (95% CI = 13.3-21.3) in 2008-2010. The temporal trend in incidence rates was modeled as a two-slope pattern, with the incidence leveling off after 2004. Based on the two classic CD symptoms of diarrhea and weight loss, the relative frequency of classical CD among incident cases decreased over time between 2000 and 2010 (P=0.044). CONCLUSIONS: The incidence of CD has continued to increase in the past decade in a North-American population.