Antithyroglobulin Antibodies in Diabetes Mellitus

Tanned red-cell hemagglutination studies for antithyroglobulin antibodies revealed prevalences of 10.1 per cent clinically significant positive tests (titers 1/25 or greater) in a group of 317 euthyroid diabetic patients free of thyroid dysfunction and of 4.0 per cent positives in a control group of 424 nondiabetic, similarly euthyroid individuals. In both groups the positive tests were more common in the females than in the males and were almost all in those of forty years of age and over. Below age forty the prevalences of tests in the diabetic and nondiabetic subjects were almost equal and of low titer. The positive tests occurred most often in the fifty- and sixty-year age group in the diabetic patients and were less frequent in the aged (seventy and over), approaching the levels observed in the corresponding age bracket in the control group. The bulk of the increase in positive tests in the diabetic group was borne by the white female (23.9 per cent) and, to a lesser degree, by the negro female (12.3 per cent) in the fifty to sixty-nine age bracket. The findings do not permit any conclusion that the thyroid gland in diabetics is involved in autoimmune disease.