Endocrine Abstracts

The aim of the study was to evaluate the effects of hyperthyroidia on glycemic control in patients with diabetes mellitus.

Research design and methods: We retrospectively evaluated the patients with diabetes and hyperthyroidism. We analysed clinical data, thyroid ultrasound exploration, laboratory analyses (glycosylated hemoglobin, free thyroxin FT4, triiodothyronine T3, thyroid stimulating hormone TSH).

Results: We evaluated 48 patients (42 women/ 6 men), mean age was 55.7±15.3 years and duration of diabetes 8.8±7.9 years; 24 patients with Graves diseases (50%), 14 with toxic multinodular goiter (29%), 7 with autonomous hyperfunctioning adenoma (14.5%), and 3 with amiodarona induced hyperthyroidism (6.5%). The treatment used for diabetes: insulin 30 (62.5%) patients, antidiabetic oral agents 11 (23%), diet 7 patients (14.5%). In the context of hyperthyroidism mean value of glycosylated hemoglobin was 9.4%±2.2% (poor glycemic control) versus 7.1%±1.6% after the treatment of hyperthyroidism. Among insulin-treated patients, the average needs of insulin in the context of hyperthyroidism was 0.72 u/kg versus 0.55 u/kg in the context of stable thyroid function (P<0.01). We found a significant association between type 1 diabetes mellitus and Graves disease compared to toxic multinodular goiter (80% vs 50%, P<0.01)

Conclusions: The presence of hyperthyroidism aggravates glycemic control of the patients with diabetes and increases insulin need in insulin-treated patients. Once the thyroid function was stable, the insulin need decreased significantly (P<0.01). Hypethyroidism must be treated radical to obtain a good glycemic control. Type 1 diabetes is significant associated to Graves disease by autoimmune mechanism.