Background and aims: Celiac disease is considered rare in North America. However, an increasing incidence and widening clinical spectrum have been reported in many countries, and serologic screening suggests a higher prevalence of minimally symptomatic disease. This study reports temporal trends in the incidence of celiac disease in Olmsted County, Minnesota.
Methods: All county residents diagnosed with celiac disease between 1950 and 2001 were identified through the Rochester Epidemiology Project. Incidence rates were calculated assuming a Poisson distribution, and changes in incidence by calendar year, age, and gender were assessed by using Poisson regression.
Results: Altogether, 82 new cases of celiac disease were identified during the 50-year period. There was a marked female predominance (P < 0.005), and the incidence rates increased with age (P < 0.001) and calendar period (P < 0.001). The overall annual incidence of celiac disease was 2.1 per 100,000 (95% confidence interval [CI], 1.7-2.6) but increased from 0.9 per 100,000 (CI, 0.5-1.2) in 1950-1989 to 3.3 per 100,000 (95% CI, 2.2-4.4) in the 1990s. The incidence was 9.1 per 100,000 (95% CI, 5.2-13.0) in the final 2 years of the study. Serology prompted biopsy in a substantial proportion of recent diagnoses. Clinical features also changed over time, with less diarrhea and weight loss at presentation.
Conclusions: Celiac disease has increased recently in this well-characterized population. Milder clinical features and use of serology suggest an increased detection rate, although a true increase in incidence may have also occurred. Celiac disease is not rare in North America.