Increased prevalence of coeliac disease in autoimmune thyroiditis is restricted to aged patients.

Patients with autoimmune thyroiditis (AT) have an increased prevalence of coeliac disease (CD), an immune-mediated enteropathy. It is unknown, however, whether prevalence of CD in AT is affected by age. Sera from 514 patients with AT aged <65 yr (46+/-12 yr), 223 patients with AT aged >or=65 yr (71+/-5 yr), 300 controls aged <65 yr (45+/-12 yr), and 300 controls aged >or=65 yr (71+/-6 yr) were tested for IgA anti-tissue transglutaminase (anti-tTG) and antiendomysial antibodies (EmA). If anti-tTG or EmA IgA were positive, jejunal biopsy was performed to confirm CD diagnosis. Prevalence of CD was significantly higher in patients with AT aged >or=65 yr (3.6%, P=0.024) than in patients with AT aged <65 yr (0.6%), controls aged <65 yr and controls aged >or=65 yr (both 0.3%). Prevalence of CD did not significantly differ across patients with AT aged <65 yr, controls aged <65 yr and controls aged >or=65 yr. In conclusion, prevalence of CD is increased in AT but the association is limited to patients aged 65 years or older. Serological screening including anti-tTG-IgA is recommended in these patients.