Introduction: the prevalence of autoimmune diseases is increased in patients with coeliac disease. Duration of gluten exposure seems to predispose adolescents with coeliac disease to autoimmune diseases. Aim: In a retrospective cohort study, we assessed the relationship between autoimmune disorders and actual gluten exposure in patients with coeliac disease. Patients and methods: the frequency of autoimmune disorders was evaluated in 64 patients (53 females, 11 males, mean age 29 years, range 16-63) with coeliac disease. The effect of age at the end of follow up, age at diagnosis of coeliac disease, actual gluten-exposure time, gender and diagnostic delay was assessed. Results: the prevalence of autoimmune diseases was 17%. Mean duration of gluten exposure was 26 and 25 years for patients with and without autoimmunity, respectively. Logistic regression showed that a longer mean follow up (P ¼ 0.044) was related to the prevalence of autoimmune disorders while actual gluten exposure was not predictive. Conclusion: in this study, the prevalence of autoimmune diseases in patients with late coeliac disease diagnosis does not correlate with duration of gluten intake. Confirmatory prospective, multicentre studies of the effect of gluten-free diet are needed in adults.