Hyperglycaemia in hyperthyroidism predictive factors

Glucose abnormalities are frequent in hyperthyroidism; the aim of our study is to determine the predisposing factors of glucose disturbances in hyperthyroidism. Subjects and methods: it is a retro and prospective study including 376 hyperthyroid subjects. Patients having fasting glycaemia < 1 g/L and/or glycaemia after 75 gr-Oral Glucose Tolerance Test (OGTT) < 1.40 g/L were compared to patients having fasting glycaemia ≥ 1 g/L and/or glycaemia after OGTT ≥ 1.40 g/L. Results: 44% had glucose abnormalities (12% diabetes and 32% prediabetes). Hyperglycemic patients were older, were more frequently hypertensive and have more familial background of diabetes than normoglycemic patients. Conclusion: Ageing, underlying hypertension and familial diabetes are risk factors for glucose abnormalities in hyperthyroid subjects whereas the severity of hyperthyroidism is not, which suggest that hyperthyroidism may worsen glucose metabolism in patients at risk of type 2 diabetes.