Insulin Sensitivity in Women with Polycystic Ovary Syndrome

Abstract

The aim of our study was to compare insulin sensitivity in lean and obese European polycystic ovary syndrome (PCOS) women with lean healthy women. We performed the euglycemic hyperinsulinemic clamp in 83 women with PCOS [53 lean with body mass index (BMI) of 21.5 ؎ 1.8 kg/m 2 and 30 obese with BMI of 29.6 ؎ 3.7 kg/m 2 ] and in 15 healthy women with BMI of 21.6 ؎ 1.8 kg/m 2 to determine glucose disposal (M) and the insulin sensitivity index (ISI). Statistical evaluation was done using Kruskal-Wallis ANOVA followed by Kruskal-Wallis multiple-comparison z-value test. The basal blood glucose was significantly higher in lean and obese PCOS women than in controls (P < 0.02). Fasting insulin was significantly higher in both lean and obese PCOS women than in controls (P < 0.000001). Obese PCOS women were more insulin resistant than controls (P < 0.02 for M and P < 0.0008 for ISI); lean PCOS women did not differ from controls in M or ISI. Posthepatic insulin delivery was significantly higher in both lean and obese PCOS women compared with controls (P < 0.000008). We conclude that lean PCOS women are not more insulin resistant than healthy controls. Insulin hypersecretion, on the other hand, is present even in lean PCOS women. IT IS GENERALLY accepted that women with polycystic ovary syndrome (PCOS) have a high prevalence of insulin resistance, with a consequent increased risk of metabolic diseases later in life. It is well established that obese PCOS women are insulin-resistant in excess of their adiposity (1, 2). In lean PCOS women, however, the situation is not so clear. To date, there have been two studies using the euglycemic hyperinsulinemic clamp that were not able to demonstrate a difference in insulin sensitivity between lean PCOS women and healthy controls in Europe (3, 4), whereas a study in the United States described significantly impaired insulin action in lean PCOS in comparison with healthy women matched for body fat and fat-free mass (2). Similar results were obtained by another group in Turkey (5). All these studies were conducted on small groups of lean women with PCOS (from 7-11 patients). These discrepancies are not easy to explain; ethnic origin of the patients could probably account for part of the differences.In the present study, we thus examined large groups of both lean and obese women fulfilling the generally accepted diagnostic criteria of PCOS, using an euglycemic clamp, which is considered the gold standard in evaluating insulin sensitivity. The aim of our study was to compare insulin sensitivity in lean and obese European PCOS women with lean controls. Subjects and MethodsThe study group consisted of 83 oligo/amenorrheic women with PCOS matching the National Institutes of Health criteria (6). All had clinical manifestation of hyperandrogenemia presenting as hirsutism and/or acne and with the elevation of the free testosterone (T) index more than six and/or androstenedione (A) above the upper limit of the normal range. Women were in good health condition, without any other serious disorder....

Incretin levels in polycystic ovary syndrome

“…Similar insulin sensitivity is consistent with other reports employing the euglycemic clamp (24,25). Other authors have also described increased C-peptide levels during OGTT, which were not accompanied by decreased insulin sensitivity as measured by euglycemic clamp in PCOS women (26).…”

The CC genotype of the GNAS T393C polymorphism is associated with obesity and insulin resistance in women with polycystic ovary syndrome

“…In women with PCOS, the impairment of insulin metabolism is thought to be influenced by both environmental (4) and genetic factors (5,6). Recently published studies from the Czech Republic (7) and Finland (8) have shown that insulin resistance and metabolic abnormalities are related to obesity rather than to PCOS per se. Obesity is a common feature of women with PCOS in different ethnic cohorts affecting about half of the entire PCOS population (9,10).…”

Resistência insulínica e perfil metabólico em pacientes com síndrome dos ovários policísticos de peso normal e sobrepeso/obesidade

“…Contudo, a TL não se correlacionou com os índices de RI (HOMA-IR), nem com a secreção insulínica (HOMA-β). Os dados da literatura são controversos: alguns (29) não encontraram correlação entre a RI (avaliada pelo HOMA-IR) e a TL, mas sim da secreção insulínica (aferida pelo HOMA-β) com a TL, reforçando o papel da hiperinsulinemia na patogênse do hiperandrogenismo na SOP (30)(31)(32). Outros (33) encontraram relação tanto dos índices de RI quanto da secreção insulínica com a TL.…”