High prevalence of organ specific autoantibodies in Indian type 1 diabetic patients

Type 1 diabetes (T1D) is frequently associated with other autoimmune conditions such as autoimmune thyroiditis, coeliac disease (CD) and Addison's disease. There are sparse data on the prevalence of antibodies against these conditions in Indian patients with T1D. This study aims to evaluate prevalence of these T1D associated autoantibodies in Indian patients.

Two hundred and fifty-eight patients with T1D were recruited from the Bangalore Diabetes Hospital and the Vydehi Institute of Medical Sciences and Research Centre (VIMS) for the study. Participants diagnosed with diabetes before the age of 18 years, as per the American Diabetes Association (ADA) criteria, and who were classified as T1D based on clinical grounds were recruited for the study. Anti-thyroid peroxidase antibody (TPO) and IgA tissue transglutaminase antibody (tTG) were estimated in all the patients. 21-Hydroxylase antibody (21-OHAb) were estimated in 170 patients. All assays were done by commercial immunoassay. Eighty-eight unrelated age-matched healthy controls were chosen for comparison.

The mean age of T1D patients was 14.33 years. The mean duration of diabetes was 4.88 years. Anti-TPO was positive in 43 (16.7%) patients with T1D as compared to 3 (3.4%) in controls. IgA tTG was positive in 12 (4.65%) patients with T1D and was absent in controls. 21-OHAb was positive in two (1.1%) patients with T1D and was absent in controls. Both patients who had positive 21-OHab had the other two antibodies. Five patients had positive anti-TPO and IgA-tTG antibodies.

Anti-TPO antibody was the most prevalent antibody in patients with T1D. Anti-TPO and IgA-tTG antibodies were significantly higher than in the control population. Further studies will be required to assess the clinical significance of these positive antibodies.