Pancreatic insulin secretion in women with polycystic ovary syndrome
Jana Vrbikova, Radovan Bilek, Marketa Vankova, Karel Vondra & Bela Bendlova
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; 0180 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; 0180 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; 0120 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.
1. Van Cauter E, Mestrez F, Sturis J & Polonsky KS. Estimation of insulin secretion rates from C-peptide levels. Comparison of individual and standard kinetic parameters for C-peptide clearance. Diabetes 1992 41 (3) 368377.