Insulin sensitivity and beta-cell function in women with polycystic ovary syndrome.
OBJECTIVE
To evaluate insulin sensitivity (IS) and beta-cell function (beta F) in lean and obese women with polycystic ovary syndrome (PCOS), either separately or by using a disposition index (DI).


METHODS
A total of 64 women with PCOS and 20 healthy women were examined by anthropometry, oral glucose tolerance tests (OGTTs), and insulin tolerance tests. Statistical analysis used one-way ANOVA, Kruskal-Wallis, and Mann-Whitney U tests, as appropriate.


RESULTS
A significantly higher waist-to-hip ratio (P < 0.0001) was found in both lean and obese women with PCOS. Higher basal blood glucose (P < 0.004) and blood glucose values at 3 h of OGTT (P < 0.008) were found in lean and obese PCOS subjects in comparison with control subjects. Insulin resistance by homeostasis model assessment (P < 0.007) was significantly higher in obese PCOS than in control or lean PCOS subjects. Early-phase insulin secretion (insulinogenic index [Delta I/Delta G(30-0), where I is insulin and G is glucose]; P < 0.0007) was significantly higher in both lean and obese PCOS subjects than in healthy women. All tested combinations of parameters of IS and beta F (DIs) followed a physiological hyperbolic relationship. Significantly lower values of the fasting state-derived DIs were found (all P < 0.05) in obese PCOS subjects. Significantly higher values of all of these indexes derived from nonfasting values were found in lean PCOS as compared with control and obese PCOS subjects (all P < 10(-3)).


CONCLUSIONS
Increased beta F was found even in lean individuals with PCOS. Insulin hypersecretion is thus probably connected to the pathogenesis of PCOS.
Vrbíková
Jana
J
Institute of Endocrinology, Prague, Czech Republic. jvrbikova@endo.cz
Bendlová
Bela
B
Hill
Martin
M
Vanková
Markéta
M
Vondra
Karel
K
Stárka
Luboslav
L
D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D005951:Glucose Tolerance Test; D006706:Homeostasis; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D008954:Models, Biological; D009765:Obesity / Q000097:blood / Q000503:physiopathology; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000503:physiopathology*
D001786:Blood Glucose; D007328:Insulin