Total body fat and central fat mass independently predict insulin resistance but not hyperandrogenemia in women with polycystic ovary syndrome.
OBJECTIVE
Obesity is a common feature of women with polycystic ovary syndrome (PCOS). The aim of this study was to assess the role of body fat on insulin resistance and androgen excess in these subjects.


METHODS
One hundred sixteen consecutive Caucasian women with PCOS, diagnosed by the Rotterdam criteria, underwent accurate assessment of clinical, anthropometric, hormonal, and metabolic features. In particular, total fat mass and fat distribution were assessed by dual-energy x-ray absorptiometry, serum-free T by liquid chromatography mass spectrometry and equilibrium dialysis and insulin sensitivity by the glucose clamp technique.


RESULTS
Total fat mass and truncal fat were significantly higher in insulin-resistant than in insulin-sensitive PCOS subjects (+89% and +127%, respectively, both P < .001), and both tended to be higher in hyperandrogenemic than in normoandrogenemic women (+22% and +28%, respectively, P = .087 and P = .090). All parameters of adiposity correlated inversely with insulin sensitivity (P < .001) and directly with serum-free T (P ≤ .001). A statistically significant inverse relationship was observed between insulin sensitivity and serum-free T concentrations (r = -0.527, P < .001). In a multiple regression analysis, either total fat mass or truncal fat, in addition to serum-free T and age, were independent predictors of insulin sensitivity. However, insulin sensitivity, but not total fat mass or truncal fat, was an independent predictor of free T concentrations.


CONCLUSIONS
These data suggest that body fat contributes to determining insulin resistance in PCOS women. However, the association between body fat and hyperandrogenism seems to be to a large extent explained by insulin resistance.
Departments of Endocrinology, Diabetes, and Metabolism (F.T., D.D., R.M., E.B., P.M.), and Obstetrics and Gynaecology (C.B.), University of Verona and Azienda Ospedaliera Universitaria Integrata of Verona, 37126 Verona, Italy; Laboratory for Hormonology and Department of Endocrinology (J.-M.K.), Ghent University Hospital, 9000 Ghent, Belgium; and Department of Public Health and Community Medicine (E.Z.), University of Verona, 37129 Verona, Italy.
Flavia
F
Tosi
Daniela
D
Di Sarra
Jean-Marc
JM
Kaufman
Cecilia
C
Bonin
Rosa
R
Moretta
Enzo
E
Bonora
Elisabetta
E
Zanolin
Paolo
P
Moghetti
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D001823:Body Composition / Q000502:physiology*; D005260:Female; D006801:Humans; D017588:Hyperandrogenism / Q000150:complications* / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D011085:Polycystic Ovary Syndrome / Q000150:complications* / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D055815:Young Adult
D007328:Insulin; D013739:Testosterone