Increasing prevalence of coeliac disease in Denmark: a linkage study combining national registries

Aim: To determine the prevalence and incidence of diagnosed coeliac disease (CD) in Danish children and adolescents and to describe trends over time. Methods: All children with a CD diagnosis registered in the Danish National Patient Registry (DNPR) were included in the study. Data were validated by combining this information with registrations of small-bowel biopsies in the National Registry of Pathology (NRP) and with a selected sample of hospital records. Results: Data were obtained from 1996 to 2010. The prevalence of CD registered in DNPR increased from 43.2 [95% CI 39.3-47.1] to 83.6 [95% CI 78.4-88.7] per 100 000, and the incidence increased from 2.8 [95% CI 1.9-3.9] to 10.0 [95% CI 8.412.0] per 100 000; 56% of the children had at least one biopsy compatible with CD registered in NRP. The incidence of biopsy-verified CD increased from 0.8 [95% CI 0.3-1.4] to 6.9 [95% CI 5.4-8.4] per 100 000. The mean age at diagnosis increased from 5.1 [95% CI 3.5-6.6] to 8.1 [95% CI 7.2-9.0] years of age. The proportion of children with associated diseases did not change over time. Conclusion: The prevalence of diagnosed CD in Danish children and adolescents has increased over the last 15 years.