Endocrine Abstracts

Aim: To study the insulin sensitivity and secretion in women with polycystic ovary syndrome (PCOS).

Subjects and methods: Thirty-eight women with PCOS (age 26.1±4.1 years, BMI 20.9±2.0 kg/m²) and 81 control healthy women (age 25.8±5.2 years, BMI 21.1±2.3 kg/m²) underwent oral glucose tolerance test (OGTT). Insulin resistance was evaluated as oral glucose index (OGIS); Matsuda and HOMA-IR, insulin secretion was calculated with our own deconvolution method based on⁽¹⁾. The time (in min) when blood glucose returned to the basal concentration was calculated for each subject and is marked as T.

Results: PCOS had higher levels of blood glucose (0-Tmin: 715.8±315 vs 594.9±262.5 nmol/l, P<0.04), insulin (0-Tmin: 34.8±18 vs 24±21.6 nmol/l; 0–180 min: 43.9±15.8 vs 34.6±21.3 nmol/l; P<0.03) and C-peptide (0-Tmin: 263.9±123.4 vs 210.9±121.9 nmol/l, P<0.03; 0–180 min: 376.7±70 vs 343.7±94.3 nmol/l; P<0.05) and had higher calculated pancreatic insulin secretion (0-Tmin: 246.9±78.4 vs 213.7±72.7 nmol/l, P<0.02; 0–120 min: 250±29.3 vs 239.8±26.8 nmol/l; P<0.07). On the other hand, HOMA-IR, Matsuda and OGIS did not significantly differ between PCOS and controls.

Conclusions: Increased insulin secretion is present in lean women with PCOS even when insulin sensitivity is not decreased in comparison with healthy women.

Supported by grant IGA MH CR NS/9839-4 and NS/9831-4.

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