BACKGROUND AND AIMS Duration of gluten exposure seems to predispose adolescents with coeliac disease to autoimmune diseases. In a retrospective cohort study, we assessed the relationship between autoimmune disorders and actual gluten exposure in patients in whom coeliac disease was diagnosed in adult life (⩾16 years).

RESULTS The prevalence of autoimmunity was threefold higher (p<0.00001) in patients than in controls. Mean duration of gluten exposure was 31.2 and 32.6 years for patients with or without autoimmunity. Logistic regression showed that increased age at diagnosis of coeliac disease was related to the prevalence of autoimmune disease while “actual gluten exposure” which takes into account diet compliance, follow up, and age at diagnosis of autoimmune disorders were not predictive for the risk of developing autoimmune diseases (odds ratio 0.82 per year).

CONCLUSION The prevalence of autoimmune diseases in patients with a late coeliac disease diagnosis does not correlate with duration of gluten intake. Early exposure to gluten may modify the immunological response. Gluten withdrawal does not protect patients with a late diagnosis from autoimmune diseases.