Gluten-free diet and autoimmune thyroiditis in patients with celiac disease. A prospective controlled study.

OBJECTIVE: Early diagnosis and dietary treatment with a gluten-free diet might slow down the progression of associated autoimmune diseases in celiac disease, but the data are contradictory. We investigated the course of autoimmune thyroid diseases in newly diagnosed celiac disease patients before and after gluten-free dietary treatment. MATERIAL AND METHODS: Twenty-seven consecutive adults with newly diagnosed celiac disease were investigated at the time of diagnosis and after 1 year on gluten-free diet. Earlier diagnosed and subclinical autoimmune thyroid diseases were recorded and examined. Thyroid gland volume and echogenicity were measured by ultrasound. Autoantibodies against celiac disease and thyroiditis, and thyroid function tests were determined. For comparison, 27 non-celiac controls on normal gluten-containing diet were examined. RESULTS: At the time of diagnosis, the celiac disease patients had more manifest (n = 7) or subclinical (n = 3) thyroid diseases than the controls (10/27 vs. 3/27, p = 0.055). During the follow-up, the thyroid volume decreased significantly in the patients with celiac disease compared with the controls, indicating the progression of thyroid gland atrophy despite the gluten-free diet. CONCLUSIONS: Celiac patients had an increased risk of thyroid autoimmune disorders. A gluten-free diet seemed not to prevent the progression of autoimmune process during a follow-up of 1 year.