AIMS: This study analysed potential sex differences in glucose metabolism of European subjects with different degrees of glucose tolerance impairment. METHODS: Subjects with impaired glucose metabolism, IGM (n = 735), or type 2 diabetes, T2DM (n = 415), were compared to subjects with normal glucose tolerance, NGT (n = 422), with similar BMI. For both males (M) and females (F), 50 years threshold was used for estimation of menopausal/andropausal state. Subjects underwent 75-g OGTT for measurements of insulin sensitivity (OGIS), beta-cell function (insulinogenic index, IGIC), and overall metabolic condition, disposition index (DI). RESULTS: In IGM, OGIS did not change with age in both sexes, whereas marked reduction of IGIC was seen in F (p = 0.0003). In T2DM, again OGIS did not change with age, but M ≥ 50 yrs had reduced IGIC and DI (p < 0.002) compared to M < 50 yrs. CONCLUSIONS: IGM did not reveal relevant changes of insulin resistance with age, but early phase insulin release deteriorated, with higher change in women. T2DM men featured age-related deterioration of glucose metabolism. In women, sex advantage seen in NGT vanished in T2DM, since glucose metabolism was overall not different than in men, both young and elderly.

Gender Medicine Unit Division of Endocrinology and Metabolism Department of Internal Medicine 3 Medical University of Vienna Waehringer Guertel 18 20 1090 Vienna Austria

Institute of Endocrinology Národní 8 PRAGUE 1 CZ 116 94 Prague Czech Republic

Internal Medicine Regional Hospital Via Castello 6777 30122 Venice Italy

Metabolic Unit CNR Institute of Neuroscience Corso Stati Uniti 4 35127 Padova Italy

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