Objectives: The aim of this study was to describe the occurrence of clinically diagnosed coeliac disease in children ages 0 to 12 years in Norway, including regional variation and coexisting type 1 diabetes mellitus, thyroid disease, and Down syndrome.
Methods: The Norwegian Patient Register (NPR) contains individual-level hospital data from 2008 onward. Small-bowel biopsies for establishing the coeliac disease diagnosis are only performed at public hospitals reporting to the NPR. Data on all hospital contacts during 2008-2011 when a diagnosis of coeliac disease was registered were retrieved from the NPR for patients born between 1999 and 2011, allowing estimation of the proportion registered with coeliac disease at ages 0 to 12 years in a cohort study.
Results: A total of 3006 individuals (58.2% girls) were recorded as having coeliac disease among 797,360 children, corresponding to a proportion of 3.8/1000 (95% confidence interval [CI] 3.7-3.9/1000) children, 4.5 (CI 4.3-4.7) among girls and 3.1 (CI 2.9-3.3/1000) among boys (P < 0.001). The proportion increased with age up to approximately 6 years and was 5.0/1000 (CI 4.5-5.6) at the age of 12 years, and was slightly higher in the south/west (3.9/1000) as compared to the middle/north (3.5/1000) regions of Norway (P = 0.013). A total of 214 of 3006 (7.1%) patients with coeliac disease were registered with coexisting conditions: type 1 diabetes mellitus (n = 142, 4.7%), Down syndrome (n = 47, 1.6%), or thyroid disease (n = 41, 1.4%).
Conclusions: In this first nationwide study of clinically diagnosed coeliac disease in Norwegian children, we found a high occurrence, comparable with that in Sweden. Comorbidity was common, but routine screening of high-risk groups contributed to a limited number of cases.