Carbohydrate metabolism in subacute thyroiditis: effect of acute elevation of thyroid hormones.

Carbohydrate metabolism was studied in nine patients with subacute thyroiditis before treatment and after recovery. The mean fasting free fatty acid level before treatment was significantly higher than that after the recovery, although the mean fasting blood glucose and insulin levels were not significantly different. Seven out of nine patients showed glucose intolerances. They returned to normal after the recovery except two cases with family histories of diabetes mellitus, whose glucose intolerances remained even 6 months after the recovery. Glucose area during oral glucose tolerance test was significantly correlated with the elevated thyroxine (r = 0.8, p less than 0.01), and triidothyronine (r = 0.66, p less than 0.05). The results indicated the importance of follow-up study of glucose tolerance in subacute thyroiditis as well as similarity of carbohydrate metabolism abnormalities in hyperthyroidism.