Celiac Disease and Risk of Autoimmune Disorders: A Population-Based Matched Birth Cohort Study.

Objectives To estimate the relative risk of developing type 1 diabetes mellitus (T1DM) and autoimmune thyroid disease in children with celiac disease (CD). Study design A matched cohort design with linkage of administrative data was adopted. A total of 1215 cases of CD and 6075 references matched by sex and year of birth born in Friuli Venezia Giulia Region (Italy) between 1989 and 2011 were included. Cox regression models were used to estimate hazard ratios (HRs) for autoimmune diseases in patients with CD compared with references, stratified by sex and age at diagnosis. Results Individuals with CD had an increased risk of subsequent hypothyroidism (HR 4.64 [95% CI 2.88-7.46]) and T1DM (HR 2.50 [95% CI 0.94-6.66]), the latter not statistically significant. Risk of hypothyroidism was higher in males (HR 20.00; 95% CI 5.64-70.87) than females (HR 3.21; 95% CI 1.85-5.57) (P value <.01). No differences were observed between males and females risks for diabetes or age at CD diagnosis. The small number of hyperthyroidism cases identified precluded any statistical analysis. Conclusions Children and youth with CD are at increased risk of developing autoimmune hypothyroidism and to some extent T1DM. This suggests the need for surveillance of children with CD in order to timely detect the onset of such comorbidities.