Metabolic syndrome in young Czech women with polycystic ovary syndrome

METHODS: Sixty-nine young women with polycystic ovary syndrome (PCOS) [age 25.2+/- 4.7 years, with body mass index (BMI) 24.3 +/- 4.8 kg/m2; mean 6 SD] and 73 age-matched healthy females (BMI 22.3 +/- 3.3 kg/m2; mean +/- SD) were evaluated for the occurrence of features of metabolic syndrome according to the Adult Treatment Panel III. RESULTS: Overt metabolic syndrome (the presence of three and more risk factors) was not more common in PCOS women (1/64, 1.6%) than in healthy controls (0/73, 0%). On the other hand, in nearly 50% of PCOS women isolated features of metabolic syndrome, most often a decrease in high-density lipoprotein (HDL) cholesterol, were found. Women with at least one feature of metabolic syndrome were, in comparison with women without any of these features, significantly more obese (P = 0.0001), with lower insulin sensitivity (P = 0.05). When comparing PCOS women according to the degree of insulin sensitivity, as determined by euglycaemic clamp, isolated features of metabolic syndrome were found in 8/17 women above the upper quartile, compared with 11/16 women below the lower quartile of insulin sensitivity (P = 0.20). CONCLUSIONS: Overt metabolic syndrome is only rarely encountered in young Czech females affected by PCOS but its isolated features are relatively frequent, both in young PCOS patients and in age-matched control women.     

Evidence of subpopulations with different levels of insulin resistance in women with polycystic ovary syndrome

BACKGROUND: Polycystic ovary syndrome (PCOS) is non-uniformly associated with insulin resistance (IR). We examined IR in women with PCOS. METHODS: Sixty-nine PCOS women were subjected to the insulin suppression test (IST) to determine their steady-state plasma glucose (SSPG) as a direct measure of insulin sensitivity. RESULTS: SSPG exhibited a multimodal distribution suggesting the existence of subpopulations. The heterogeneous distribution of plasma glucose at 180 min (P = 0.011), with three modes, suggested differences in the plasma glucose level trajectories during the IST. Hence, the population was separated into three groups: (i) (n = 33), subjects with SSPG < or = 152.5 mg/dl, corresponding to the first to fifth deciles; (ii) (n = 29), subjects in the interval 152.5 mg/dl < SSPG < or = 300 mg/dl; (iii) (n = 7), subjects with SSPG > 300 mg/dl, corresponding to the tenth decile. Plasma glucose distributions at 180 min showed differences in their mean values and ranges among groups (P < 0.0001). The trajectories of the groups differed significantly during the IST (P < 0.0001). CONCLUSIONS: insulin sensitivity in our patients exhibited a discontinuous distribution, implying that PCOS is a heterogeneous disorder possessing subpopulations regarding IR.     

Leptin, polycystic ovaries and polycystic ovary syndrome.

As soon as leptin was discovered four years ago, its potential as a player in the polycystic ovary syndrome (PCOS) was explored in a primitive way, though little light was shed on the enigma that is PCOS. As a second wave of leptin research is now available, we review how the expanded role of the cytokine in reproduction might yet impact upon our understanding of PCOS.     

Serum visfatin in relation to insulin resistance and markers of hyperandrogenism in lean and obese women with polycystic ovary syndrome

BACKGROUND: Visfatin, a protein secreted by adipose tissue, is suggested to play a role in pathogenesis of insulin resistance. In polycystic ovary syndrome (PCOS), insulin resistance might be involved in the development of endocrine and metabolic abnormalities. The aim of the study was to asses the relation between serum visfatin concentration and insulin sensitivity and markers of hyperandrogenism in lean and obese PCOS patients. METHODS: The study group consisted of 70 women with PCOS (23 lean and 47 obese) and 45 healthy women (25 lean and 20 obese). Euglycemic hyperinsulinemic clamp and the measurements of serum visfatin, sex hormones were performed. RESULTS: The PCOS group had lower insulin sensitivity (P=0.00049) and higher serum visfatin (P=0.047) in comparison to the control group. The decrease in insulin sensitivity was present in both the lean (P=0.019) and obese (P=0.0077) PCOS subjects, whereas increase in serum visfatin was observed only in lean PCOS subjects (P=0.012). In the whole group, serum visfatin was negatively correlated with insulin sensitivity (r=-0.27, P=0.004). This relationship was also observed in the subgroup of lean (r=-0.30, P=0.038), but not obese women. Additionally, in lean women, visfatin was associated with serum testosterone (r=0.47, P=0.002) and free androgen index (r=0.48, P=0.002), independently of other potential confounding factors. CONCLUSIONS: Visfatin is associated with insulin resistance and markers of hyperandrogenism in lean PCOS patients.     

多囊卵巢综合征胰岛素抵抗相关治疗进展

 胰岛素抵抗（IR）是多囊卵巢综合征（PCOS）重要发病机制之一。临床上应用二甲双胍或噻唑烷二酮类药物可改善PCOS患者IR,纠正其代谢紊乱和高雄激素血症,故有助于恢复正常月经,增加排卵率及妊娠率,且孕期应用二甲双胍可能减少流产、妊娠高血压病、妊娠糖尿病等并发症。     

Follicular hyperandrogenism and insulin resistance in polycystic ovary syndrome patients with normal circulating testosterone levels

Polycystic ovary syndrome (PCOS) is a common reproductive disease with high heterogeneity. The role of excess androgen in PCOS etiology remains disputed, since around 20%–50% of PCOS women do not display hyperandrogenemia. The microenvironment of the ovary critically influences follicular development. In the present study, we assessed the role of androgen in PCOS by investigating whether excessive follicular fluid androgen was present in PCOS patients with normal serum androgen levels and influenced by follicular fluid insulin resistance (IR). Follicular fluid samples of 105 women with PCOS and 105 controls were collected. Levels of steroid hormones, glucose and insulin in the follicular fluid were examined and compared with data from serum biochemistry tests. We found that 64.9% (63/97) of PCOS patients with normal serum androgen levels displayed abnormally high follicular fluid androgen level. The follicular fluid androgen level was positively correlated with follicular fluid IR within a certain range and follicular fluid estrogen-to-testosterone (E2/T) ratio was significantly reduced in these patients. These results indicated that there existed a subgroup of PCOS patients who displayed excessive follicular fluid androgen and IR despite their normal circulating testosterone (T) levels. Our study highlights the importance of ovary hyperandrogenism and IR in the etiology of PCOS.     

Endocrinology: Normal serum uric acid concentrations in women with polycystic ovary syndrome

Recently, an inverse correlation between serum uric acid concentrationsand insulin sensitivity has been described in subjects withvarying degrees of metabolic syndrome, suggesting that measurementof serum uric acid may provide a simple marker of insulin resistance.Several biochemical and clinical features of polycystic ovarysyndrome (PCOS) resemble those of metabolic syndrome: womenwith PCOS are often obese; they are also at increased risk forthe development of coronary artery disease, hypertension anddiabetes mellitus. The objective of the present study was toanalyse the usefulness of serum uric acid measurement in screeningfor the metabolic syndrome in women with PCOS. For that purposeserum concentrations of uric acid, insulin and triglycerideswere measured in 38 women with PCOS and 20 weight-matched controlwomen with regular menstrual cycles. No differences were foundin the uric acid concentrations between the PCOS and controlgroups. The mean concentrations of triglycerides and fastinginsulin were higher in the women with PCOS than in the healthycontrols. Serum uric acid concentrations were inversely relatedto serum hormone-binding globulin (SHBG) concentrations, andpositively with body mass index (BMI), insulin concentrationsand testosterone:SHBG ratio in the PCOS group. Our results suggestthat measurement of serum uric acid does not provide new meansfor identification of metabolic syndrome in patients with PCOS.     

Pioglitazone and metformin in obese women with polycystic ovary syndrome not optimally responsive to metformin

BACKGROUND: In an observational study of 13 women with polycystic ovary syndrome (PCOS) not optimally responsive to metformin diet, we assessed the efficacy and safety of addition of pioglitazone. We also compared these 13 women to 26 women with PCOS, who were responsive to metformin diet, matched by age and by pre- treatment menstrual history and not different by obesity categories. METHODS: Prospectively, as outpatients, with diet constant [1500-2000 calorie (depending on entry body mass index), 26% protein, 44% carbohydrate, 30% fat], metformin (2.55 g/day) was given for 12 months to 39 women, 13 not optimally responsive, 26 responsive to metformin diet, followed by addition of pioglitazone (45 mg/day) for 10 months in the 13 non-responders. Outcome measures included changes in sex hormones, insulin, insulin resistance (IR), insulin secretion, high density lipoprotein cholesterol, weight, and menstrual status. RESULTS: In 13 non-responders, on metformin diet, median serum insulin fell (21 to 16 microIU/ml, P<0.05) and insulin secretion fell from 251 to 200 (P<0.01); weight, dehydroepiandrosterone sulphate (DHEAS), testosterone and IR were unchanged (P> or =0.07). Compared with 14% pre- treatment, on metformin diet, expected menses occurred 46% of the time at 3 months (P=0.05), 38% at 6 months (P=0.07), 27% at 9 months, and 24% at 12 months. In 26 responders, on metformin diet, median weight fell (93 to 87 kg), testosterone fell (50 to 32 ng/dl), insulin fell (26 to 16 microIU/ml), IR fell (5.32 to 3.45) and insulin secretion fell (351 to 271) (P< or =0.017 for all). The occurrence of expected menses in the 26 responders was 2.5-fold higher than in the 13 non-responders (P<0.0001). In 11 non-responders, on pioglitazone + metformin diet over 10 months versus antecedent metformin diet, DHEAS fell (211 to 171 microg/dl, P=0.02), insulin fell (16 to 10 microIU/ml, P= 0.001), IR fell (3.37 to 1.73, P=0.002), insulin secretion fell (217 to 124, P=0.004), sex hormone-binding globulin rose (31 to 43 nmol/l, P=0.006), and HDL cholesterol rose (38 to 42 mg/dl, P=0.003). On pioglitazone + metformin diet, the occurrence of expected menses was 2-fold higher than on metformin diet (P<0.0001). CONCLUSIONS: In women with PCOS who failed to respond optimally to metformin, when pioglitazone was added, insulin, glucose, IR, insulin secretion, and DHEAS fell, HDL cholesterol and sex hormone-binding globulin rose, and menstrual regularity improved, without adverse side-effects.     

Association between polycystic ovary syndrome and female-to-male transsexuality

BACKGROUND: The aim of this study is to understand the relationship between polycystic ovary syndrome (PCOS), altered hormonal characteristics and insulin resistance in female-to-male (FTM) transsexual patients. METHODS: We studied 69 Japanese FTM cases, aged 17-47 years, who were seen in the Gender Identity Disorder Clinic of Sapporo Medical University Hospital between December 2003 and May 2006. The subjects had never received hormonal treatment or sex re-assignment surgery. Prior to treatment, they received physical examinations entailing measurement of anthropometric, metabolic and endocrine parameters, after which we compared the values obtained according to the presence or absence of PCOS and/or obesity. Insulin resistance was determined using the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Of the 69 participating FTM cases, 40 (58.0%) were found to have PCOS. Of the 49 for whom HOMA-IR was calculated, 15 (30.6%) also showed insulin resistance, whereas of the 59 for whom adiponectin was measured, 18 (30.5%) showed hypoadiponectinaemia. Of 69 for whom androgens were measured, 29 (39.1%) showed hyperandrogenaemia. Insulin resistance was associated with obesity but not with PCOS. In contrast, hyperandrogenaemia was associated with both PCOS and obesity. CONCLUSION: FTM transsexual patients have a high prevalence of PCOS and hyperandrogenaemia.     

Endocrinology: Insulin resistant and non-resistant polycystic ovary syndrome represent two clinical and endocrinological subgroups

We studied the clinical and endocrine features of 35 patientswith polycystic ovary syndrome (PCOS) who are either insulinresistant or non-insulin resistant. The occurrence of insulinresistance was determined by measuring insulin and glucose concentrationsfollowing a standard 75 g oral glucose load. All patients wereevaluated by anthropometric measurements: body mass index (BMI),percentage of body fat (BCF) and waist-to-hip ratio (W/H), degreeof hirsutism (Ferriman-Gallwey method) and endocrine profile.Fourteen patients had insulin resistance of unknown origin whereasfour were due to a type A insulin receptor mutation, and 17were non-insulin resistant. The insulin resistant patients weresignificantly more obese (higher BMI P < 0.0001, BCF P <0.002 and W/H ratio P < 0.005) and were more hirsute (P <0.002) than the non-insulin resistant patients. Testosteroneconcentrations were significantly higher in the insulin resistantgroup than in the non-insulin resistant group (2.65 versus 1.37nmol/l; P < 0.027), whereas sex hormone-binding globulinwas lower in insulin resistant patients (30.61 versus 19.48nmol/l; P < 0.02). Non-insulin resistant patients showeda high luteinizing hormone to follicle stimulating hormone ratio,while a normal ratio was found in the insulin resistant subpopulation(2.94 versus 1.34; P < 0.0001). We concluded that PCOS comprisestwo subpopulations, one with insulin resistance of differentaetiologies and the other which has no insulin resistance. Thesetwo groups differ in their anthropometric and endocrine features.The diagnosis of insulin resistance in PCOS can be easily determinedby the insulin response to an oral glucose tolerance test.     

Elevated ambulatory day-time blood pressure in women with polycystic ovary syndrome: a sign of a pre-hypertensive state?

The aim of this study was to evaluate office and 24 h bloodpressures in women with polycystic ovary syndrome (PCOS) andnormal controls in relation to insulin sensitivity. Office bloodpressure, insulin sensitivity (euglycaemic hyperinsulinaemicclamp) and body fat distribution (skin-folds, waistrhip ratio)were investigated in 36 women with PCOS and 55 controls [bodymass index (BMI) for PCOS patients, mean (confidence interval)263 (24.6–282); controls, 25.1 (24.0–26.9)], andambulatory 24 h blood pressure was recorded in representativesubgroups of 17 and 16 women respectively. Compared with thecontrols, the women with PCOS had higher day-time systolic (meanSD,12611 versus 11912 mm Hg, P < 0.05) and mean arterial bloodpressures (927 versus 867 mm Hg, P < 0.05) in ambulatoryrecordings, and greater increases in pulse rate (70%; P <0.05) from night to day-time recordings, whereas the groupsdid not differ significantly in day-time diastolic blood pressure(746 versus 706 mm Hg, P = 0.05) or in night-time recordings.The women with PCOS had a more pronounced truncal-abdominalfat distribution (P < 0.05) and a lower insulin-mediatedglucose disposal (P < 0.01) during the clamp. The increasedday-time blood pressures in women with PCOS persisted afteradjusting for BMI, body fat distribution and insulin resistance.It is concluded that women with PCOS have an increased prevalenceof labile blood pressure, which may indicate a pre-hypertensivestate, adding a further risk factor for cardiovascular diseasein these women.     

Effects of two antiandrogen treatments on hirsutism and insulin sensitivity in women with polycystic ovary syndrome

Thirty-two women with polycystic ovary syndrome (PCOS) wereallocated to two antiandrogen treatment regimens; 28 women completedthe trial. Twenty women were treated with ethinyloestradioland cyproterone acetate (EO-CA) cyclically for 6 months andeight women were treated with the gonadotrophin releasing hormone(GnRH) analogue, goserelin for 6 months. Effects on hirsutism,insulin sensitivity (estimated by glucose clamp technique),blood lipids and hormones were measured. Women treated withEO-CA showed a reduction in hirsutism (P <0.05), and decreasedserum androgen concentrations (P <0.001) as well as reducedinsulin sensitivity (P <0.05). In women treated with goserelin,serum androgen concentrations also decreased (P <0.001),but there was no significant reduction of hirsutism. This group,however, showed an improved insulin sensitivity (P <0.05)despite an unchanged body mass index. Bone mineral density wasunaltered in both treatment groups. The reduction in androgenconcentrations caused by EO-CA was not paralleled by increasedinsulin sensitivity, most probably due to the effect of ethinyloestradiolper se. In contrast, the reduction in androgen concentrationsby goserelin was accompanied by an improved insulin sensitivity.     

The excess in 2-5 mm follicles seen at ovarian ultrasonography is tightly associated to the follicular arrest of the polycystic ovary syndrome

BACKGROUND: We previously hypothesized that the excess of 2–5 mmfollicles seen at ovarian ultrasonography might be involvedin the follicular arrest (FA) of polycystic ovary syndrome (PCOS),independently from the main putative contributors of FA, namelyhyperandrogenism and hyperinsulinism. METHODS: A multivariate statistical analysis was applied retrospectivelyto clinical, biological and ultrasound data that were consecutivelycollected during 5 years in 457 patients with polycystic ovariesand in 188 age-matched non-hyperandrogenic and regularly cyclingcontrols without PCO at ultrasound. RESULTS: Stepwise discriminant analysis indicated that in PCOS the 2–5 mmfollicle number (FN) gave the strongest correlation to severityof the FA, followed by age and then by fasting insulin level.The other variables [waist circumference (WC), 6–9 mmFN, serum testosterone, FSH, LH and ovarian area] were rejectedby the analysis. Multiple linear regression indicated a significantand independent negative relationship between the 2–5and 6–9 mm FN in the PCOS (r = – 0.186, P <0.01) and control groups (r = – 0.281, P < 0.01). InPCOS only, the 6–9 mm FN was negatively and independentlyrelated to the WC (r = – 0.108, P < 0.05). CONCLUSIONS: The size of the 2–5 mm follicle pool is an independentand important contributor to the FA of PCOS. This result couldbe explained by an exaggerated physiological inhibitory effectfrom this pool on the terminal follicle growth. The metabolicderangement of PCOS that also contributes to the FA would actthrough a different mechanism.     

Adipocyte resistin mRNA levels are down-regulated by laparoscopic ovarian electrocautery in both obese and lean women with polycystic ovary syndrome

BACKGROUND: The aim of this study was to investigate serum and adipocyte mRNA expression of resistin in lean and obese women with polycystic ovary syndrome (PCOS) before and 3 months after laparoscopic ovarian electrocauterization (LOE). METHODS: Adipose tissue obtained from 12 women with PCOS (six obese and six lean, body mass index > 27 kg m(-1) as threshold point) before and after LOE was analysed. Gene expression of resistin was measured by semi-quantitative RT-PCR. Ten lean, age-matched healthy women served as controls. RESULTS: Both lean and obese women with PCOS had significantly higher fasting and 2 h insulin and homeostasis model insulin resistance index (HOMA(IR)) values and lower fasting glucose-to-insulin ratios (G(0)/I(0)) than did the controls. The serum levels of glucose and insulin and HOMA(IR) were significantly decreased, and the G(0)/I(0) ratio was significantly increased 3 months after LOE. No difference was found in serum resistin levels between controls and either obese or lean women with PCOS before LOE, nor between PCOS patients before and after LOE. However, resistin mRNA expression levels in both lean and obese women with PCOS before LOE were significantly higher than that in controls and were decreased significantly after LOE back to control levels. CONCLUSION: Local resistin activity may be actively involved in the pathogenesis of PCOS. LOE reduces insulin resistance and down-regulates resistin mRNA expression in lean and obese women with PCOS.     

Women with polycystic ovary syndrome gain regular menstrual cycles when ageing

The aim of this study was to investigate if previously oligo- or amenorrhoeic polycystic ovary syndrome (PCOS) patients gain regular menstrual cycles when ageing. Women registered as having PCOS, based on the combination of oligo- or amenorrhoea and an increased LH concentration, were invited by letter to participate in a questionnaire by telephone. In this questionnaire we asked for the prevalent menstrual cycle pattern, which we scored in regular cycles (persistently shorter than 6 weeks) or irregular cycles (longer than 6 weeks). We interviewed 346 patients of 30 years and older, and excluded 141 from analysis mainly because of the use of oral contraceptives. The remaining 205 patients showed a highly significant linear trend (P < 0.001) for a shorter menstrual cycle length with increasing age. Logistic regression analysis for body mass index, weight loss, hirsutism, previous treatment with clomiphene citrate or gonadotrophins, previous pregnancy, ethnic origin and smoking showed no influence on the effect of age on the regularity of the menstrual cycle. We conclude that the development of a new balance in the polycystic ovary, solely caused by follicle loss through the process of ovarian ageing, can explain the occurrence of regular cycles in older patients with PCOS.     

Microvascular dysfunction in women with polycystic ovary syndrome

BACKGROUND: Polycystic ovary syndrome (PCOS) is associated with multiple cardiovascular risk factors and an increased prevalence of arterial dysfunction. However, microvascular dysfunction in PCOS has not been assessed. METHODS: Subjects comprised 12 women with PCOS and 12 age-matched controls with normal ovaries. Microvascular function was assessed by observing forearm skin microvascular erythrocyte flux responses, to cumulative iontophoretic doses of 1% (w/v) acetylcholine (ACh) and 1% (w/v) sodium nitroprusside (SNP), using laser Doppler imaging. RESULTS: Basal microvascular perfusion was comparable in PCOS and controls. The increase in skin microvascular perfusion in response to ACh was however generally blunted in PCOS women (P = 0.018). Peak ACh-induced erythrocyte flux was also less (p < 0.04) in PCOS women (125.1 +/- 21.7, i.e. 5.3-fold basal flux) than in controls (200.8 +/- 28.5, i.e. 8.3-fold basal flux). Analysis of covariance indicated this effect was unrelated to differences in body mass index or serum testosterone but serum insulin may be a weak confounder. No differences were noted between the PCOS and control groups in their response to SNP. CONCLUSION: Despite its limited sample size studied, this is the first demonstration that women with PCOS exhibit microvascular endothelial dysfunction, indicated by an inhibited vasodilatory response to ACh.     

Endocrinology: Subjects with polycystic ovaries without hyperandrogenaemia exhibit similar disturbances in insulin and lipid profiles as those with polycystic ovary syndrome

Polycystic ovaries (PCO) are detected using ultrasonographyin a proportion of women who do not have clinical symptoms ofthe polycystic ovary syndrome (PCOS). The aim of this studywas to compare the metabolic and endocrine differences betweenwomen with such ultrasound-detected PCO and women with PCOS,and to relate these changes to clinical presentation with particularreference to cycle irregularity. A group of 118 women showingPCO on vaginal ultrasound scan was divided into those who hadno hyperandrogenaemia (n = 21) and those who had increased androgensand a clinical presentation normally associated with PCOS (n= 97). These were compared with a reference group of 26 normalsubjects. Glucose tolerance, lipid concentrations and endocrineprofiles were compared between groups. Apart from higher concentrationsof androgens in the PCOS group, there were no significant differencesbetween the PCO and PCOS groups in either fasting and stimulatedinsulin and glucose or in concentrations of sex hormone-bindingglobulin, gonadotrophins and blood lipids or in ovarian volume.Both PCO and PCOS subjects with cycle irregularity had significantlyhigher concentrations of serum fasting and stimulated insulinindependent of androgens and body mass index than those withnormal cycles. It was concluded that: (i) PCO and PCOS patientshave equivalent disturbances in relation to insulin and glucosemetabolism as well as lipid and lipoprotein disturbances comparedto reference subjects; (ii) higher serum insulin values areassociated with menstrual irregularity in both groups; (iii)ultrasound evidence for PCO predicts similar metabolic sequelaeto PCOS and can therefore be used for studies of the geneticsand long term risks for this condition.     

Comparison of the effects of acarbose and metformin use on ovulation rates in clomiphene citrate-resistant polycystic ovary syndrome

BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS.     

Leptin concentrations in hirsute women with polycystic ovary syndrome or idiopathic hirsutism: influence on LH and relationship with hormonal, metabolic, and anthropometric measurements.

BACKGROUND: The known association between leptin, obesity and insulin action suggests that leptin may have a role in polycystic ovarian syndrome (PCOS) but this has only been addressed peripherally. METHODS: We assessed the influence of leptin on LH and investigated the relationship between leptin and body mass index (BMI), waist:hip ratio (WHR), androgen concentrations, fasting insulin and insulin:glucose ratio (IGR) in 27 women with PCOS and in 20 age- and weight-matched women with regular, ovulatory menstrual cycles and idiopathic hirsutism (IH). RESULTS: Leptin concentrations were significantly higher in obese PCOS women than in normal weight women with either PCOS or IH (P = 0.0028), but did not differ between obese women with PCOS and IH. WHR, insulin concentrations and IGR were significantly higher in obese PCOS patients in comparison with the three other groups. In IH patients, the association between leptin concentrations and WHR was lost after adjustment for BMI. In PCOS patients, a significant correlation was observed between leptin and fasting insulin concentrations, IGR, WHR and LH. After adjustment for BMI, only the correlation with LH remained significant. A stepwise regression model was set up with LH as the dependent variable to test the hypothesis that the concentrations of leptin might be modulating the concentrations of LH in PCOS patients. The relationship of LH concentrations with IGR was found to be BMI dependent. In contrast, leptin concentrations contributed negatively and significantly to LH concentrations, independently of either BMI or IGR. CONCLUSIONS: We speculate that the known attenuation in basal or stimulated response of LH in obese PCOS patients might be related to leptin resistance, which could influence LH hypersecretion. In IH ovulatory patients, normal LH concentrations suggest the presence of preserved regulatory mechanisms of GnRH pulsatility. Further studies are needed to specifically investigate the proposed correlation between leptin and GnRH modulation in PCOS.     

The relationship between anti-Mullerian hormone, androgen and insulin resistance on the number of antral follicles in women with polycystic ovary syndrome

BACKGROUND: Anti-Müllerian hormone (AMH) is a biomarker that predicts the number of antral follicles and is involved in follicle arrest for women with polycystic ovary syndrome (PCOS). We investigated the association between the characteristic hyperandrogenemia, insulin resistance (IR), AMH, and the morphology and size of ovaries for women with PCOS. METHODS: A total of 99 Taiwanese women with PCOS who were willing to undergo vaginal ultrasonography were enrolled in this cross-sectional study. RESULTS: The number of antral follicles and the ovarian volume showed a significant correlation with AMH, total testosterone and the free androgen index, but not with age, body mass index (BMI) or the homeostasis model assessment of insulin resistance (HOMA-IR). AMH had a significant negative association with both BMI and HOMA-IR. Multiple stepwise regression analysis demonstrated that AMH, BMI and total testosterone were independently related to the number of antral follicles. AMH and total testosterone were the main determinants for ovarian volume in a stepwise regression model. CONCLUSIONS: Our results suggest that not only the AMH level, but also obesity, IR and elevated androgen levels may relate to the development of the large size of antral follicle pool and ovarian volume in women with PCOS. Obesity and IR may enhance the follicular excess through the dysregulation of AMH or through the pathway of hyperandrogenemia. These findings might partly explain why adequate body weight management and improvement in IR can improve the ovulatory function for women with PCOS.