Associated thyrogastric autoimmunity increases the prevalence of low erythrocyte magnesium in type 1 diabetes

A group of 230 type 1 (insulin-dependent) diabetic patients were screened for the presence of thyrogastric autoantibodies (aTPO and PCA) and magnesium depletion. Thirty-seven per cent presented with significant levels of 1 autoantibody and 7 per cent were positive for both. Exactly 25 per cent of the subjects had low levels of erythrocyte Mg (RBC-Mg < 5.5 mg/dl). Female patients were more prone to lower RBC-Mg and had a significant higher prevalence of aTPO and, although actually euthyroid, had a more pronounced history of thyroid disease. The presence of both antibodies was accompanied with the highest prevalence of low RBC-Mg. However, PCA positivity with hypergastrinaemia alone did not show a significant increase of the Mg depletion. The mechanisms involved in this phenomenon remain unclear but besides gender, duration of diabetes and the metabolic consequences of the disease, the presence of associated thyroid and gastric dysfunction can play a supplementary role in the maintenance of the chronic Mg problems in type 1 diabetes.