QT dispersion in patients with polycystic ovary syndrome

Cardiac risk factors are observed more frequently in patients with polycystic ovary syndrome (PCOS). On the other hand, increased QT dispersion, which is a risk factor for cardiac arrhythmias and sudden death, has not been investigated in this syndrome. In this study, we evaluated QT dispersion in PCOS patients without overt heart disease. Thirty-six consecutive women with PCOS (mean age 24+/-5 years) and 36 healthy women of similar ages (mean age 24+/-4 years) participated in this study. PCOS was diagnosed if there were polycystic ovaries by ultrasound (enlarged ovaries with > or =8 cysts 2-8 mm in diameter), oligoamenorrhea (intermenstrual interval >35 days), hirsutism (Ferriman-Gallwey score, > or =7) and elevated serum levels of testosterone (> or =2.7 nmol/L). Electrocardiograms were recorded at a paper speed of 50 mm/s. QT intervals were manually measured by a cardiologist. All intervals were corrected for heart rate according to Bazett's formula: QTc interval=QT interval/square root of the RR interval. Mean values of body mass index, heart rate, and blood pressure were not significantly different between the two groups (P>0.05). No significant differences in QT intervals (maximum QT, minimum QT, QT dispersion, minimum corrected QT, maximum corrected QT, and corrected QT dispersion) were observed between the two groups (P>0.05). Our results suggest that the risk of ventricular arrhythmias or sudden cardiac death is not increased in PCOS patients.     

Circulating ghrelin levels in patients with polycystic ovary syndrome

The syndrome of polycystic ovaries (PCOS) is associated with adiposity and metabolic changes predisposing to insulin resistance and diabetes mellitus. Because the recently discovered GH secretagogue, ghrelin, is intimately involved in the control of appetite and weight regulation, we studied ghrelin levels in a group of 26 otherwise healthy women with PCOS. They were compared with 61 healthy female control subjects and 5 gastrectomized women. Insulin sensitivity was assessed by homeostasis model assessment (HOMA) and continuous infusion of glucose with model assessment (CIGMA) in all patients. In PCOS women, serum ghrelin levels were significantly lower than in healthy lean or obese controls (P < 0.001). In insulin-sensitive PCOS women, ghrelin concentrations compared well with the healthy controls, whereas in insulin-resistant PCOS ghrelin levels were significantly lower and indistinguishable from the low levels found in the gastrectomized women. There was a close correlation of ghrelin to insulin sensitivity (HOMA, r(2) = 0.330, P < 0.002; CIGMA, r(2) = 0.568, P < 0.0001). Treatment of 10 insulin-resistant PCOS women with metformin significantly increased circulating fasting ghrelin concentrations (P < 0.02). Ghrelin levels did not correlate to any of the parameters of hyperandrogenemia, to the LH/FSH ratio, to body mass index, or to fasting insulin and glucose concentrations. In summary, ghrelin levels are decreased in PCOS women and are highly correlated to the degree of insulin resistance. This suggests that ghrelin could be linked to insulin resistance in PCOS women. However, whether low ghrelin in PCOS is a cause or the consequence of insulin resistance awaits further investigations.     

多囊卵巢综合征卵巢局部胰岛素抵抗的生物学效应

多囊卵巢综合征(PCOS)是生殖功能障碍与代谢异常并存的一种特殊疾病.生殖功能障碍包括卵巢排卵功能障碍和雄激素过多,是PCOS患者临床表现的核心内容;代谢异常主要表现为胰岛素抵抗和高胰岛素血症.近期研究发现PCOS患者除胰岛素作用的经典靶组织--骨骼肌、脂肪和肝脏存在胰岛素抵抗之外,卵巢局部也存在胰岛素抵抗 [1].同时2型糖尿病患者存在胰岛素抵抗和外周高胰岛素血症的表现,但并不常见卵巢功能障碍,很显然以卵巢组织外的胰岛素抵抗和外周的高胰岛素血症来解释卵巢本身的功能异常是不确切的.因此,卵巢本身的胰岛素抵抗对PCOS患者卵巢功能改变有更重要的意义.     

Risk of cardiovascular events in patients with polycystic ovary syndrome

Women with polycystic ovary syndrome (PCOS) have increased prevalence of cardiovascular (CV) risk factors. However, data on the incidence of CV events are lacking in this population. Using Rochester Epidemiology Project resources, we conducted a retrospective cohort study comparing CV events in women with PCOS with those of women without PCOS in Olmsted County, Minnesota. Between 1966 and 1988, 309 women with PCOS and 343 without PCOS were identified. Mean (SD) age at PCOS diagnosis was 25.0 (5.3) years; mean age at last follow-up was 46.7 years. Mean (SD) follow-up was 23.7 (13.7) years. Women with PCOS had a higher body mass index (29.4 kg÷m2 vs 28.3 kg÷m2; p=.01). Prevalence of type 2 diabetes mellitus and hypertension and levels of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides were similar in the two groups. We observed no increase in CV events, including myocardial infarction (adjusted hazard ratio [HR] 0.74; 95% confidence interval [CI] 0.32 to 1.72; p=.48); coronary artery bypass graft surgery (adjusted HR 1.52; 95% CI 0.42 to 5.48; p=.52); death (adjusted HR 1.03; 95% CI, 0.29 to 3.71; p=.96); death due to CV disease (adjusted HR 5.67; 95% CI 0.51 to 63.7; p=.16); or stroke (adjusted HR 1.05; 95% CI 0.28 to 3.92; p=.94). Although women with PCOS weighed more than controls, there was no increased prevalence of other CV risk factors. Furthermore, we found no increase in CV events. While prospective studies are needed to confirm these findings, women with PCOS do not appear to have adverse CV outcomes in midlife.     

Altered multihormone synchrony in obese patients with polycystic ovary syndrome

Luteinizing hormone (LH) concentrations and pulsatility are increased in obese women with polycystic ovary syndrome (PCOS). In addition, patients have hyperandrogenemia and insulin resistance. The mechanisms involved in aberrant hormone regulation in PCOS are still unclear. We investigated 15 obese PCOS women with a body mass index between 30 and 54 kg/m² and 9 healthy obese controls (body mass index, 31-60 kg/m²) with regular menstrual cycles. Subjects underwent 24-hour blood sampling at 10-minute intervals for later measurements of LH, leptin, testosterone, and insulin concentrations. Data were analyzed with a new deconvolution program, approximate entropy (and bivariate approximate entropy), and a cross-correlation network. Patients had increased LH pulse frequency and more than 2-fold greater daily LH secretion, with diminished pattern regularity. Testosterone secretion was increased 2-fold, but pattern regularity was similar to that in controls. In the network construct, insulin was correlated positively with LH, whereas leptin and testosterone were correlated negatively with LH. Bivariate synchrony of LH with insulin was decreased. Short-term caloric restriction paradoxically increased LH secretion by 1.5-fold and pattern irregularity, and reduced interpulse variability. Testosterone secretion and fasting concentrations of estradiol and sex hormone-binding globulin levels remained unchanged. Correlations between LH and insulin, leptin, and calculated free testosterone decreased. This study demonstrates marked alterations in the control of LH secretion in PCOS in the fed and calorie-restricted states. The ensemble results point to abnormal feedback control of not only the GnRH-gonadotrope complex, but also LH's relationships with leptin, insulin, and testosterone.     

High prevalence of autoimmune thyroiditis in patients with polycystic ovary syndrome

OBJECTIVE: To investigate the prevalence of autoimmune thyroiditis (AIT) in patients with polycystic ovary syndrome (PCOS). DESIGN: Over a period of 30 months, 175 patients with PCOS were recruited to a prospective multicenter study to evaluate thyroid function and morphology; 168 age-matched women without PCOS were studied as a control group. METHODS: PCOS was defined as a- or oligomenorrhea, hyperandrogenism and exclusion of other disturbances of estrogen or androgen synthesis. All laboratory parameters were determined with automated immunoassays. Thyroid morphology was assessed by ultrasound. RESULTS: PCOS patients were characterized by an increased LH/FSH ratio, low progesterone, elevated testosterone and a high prevalence of hirsutism (PCOS 83%, control 3%; mean hirsutism score 12+/-5 and 3+/-2 respectively), but no differences in estrogen levels were found. Thyroid function and thyroid-specific antibody tests revealed elevated thyroperoxidase (TPO) or thyroglobulin (TG) antibodies in 14 of 168 controls (8.3%), and in 47 of 175 patients with PCOS (26.9%; P<0.001). On thyroid ultrasound, 42.3% of PCOS patients, but only 6.5% of the controls (P<0.001) had a hypoechoic tissue typical of AIT; while thyroid hormone levels were normal in all subjects, PCOS patients had a higher mean TSH level (P<0.001) and a higher incidence of TSH levels above the upper limit of normal (PCOS 10.9%, controls 1.8%; P<0.001). CONCLUSION: This prospective study demonstrates a threefold higher prevalence of AIT in patients with PCOS, correlated in part with an increased estrogen-to-progesterone ratio and characterized by early manifestation of the disease.     

Thyroidal effect of metformin treatment in patients with polycystic ovary syndrome

Objective Metformin is widely used for the treatment of type 2 diabetes. Growing evidence supports the beneficial effects of metformin also in patients with polycystic ovary syndrome (PCOS). It was recently reported that metformin has a TSH‐lowering effect in hypothyroid patients with diabetes being treated with metformin. Design Aim of this study was to evaluate the effect of metformin treatment on the thyroid hormone profile in patients with PCOS. Patients and measurements Thirty‐three patients with PCOS were specifically selected for being either treated with levothyroxine for a previous diagnosis of hypothyroidism (n = 7), untreated subclinically hypothyroid (n = 2) or euthyroid without levothyroxine treatment (n = 24) before the starting of metformin. The serum levels of TSH and FT₄ were measured before and after a 4‐month period of metformin therapy. Results Thyroid function parameters did not change after starting metformin therapy in euthyroid patients with PCOS. In the 9 hypothyroid patients with PCOS, the basal median serum levels of TSH (3·2 mIU/l, range = 0·4–7·1 mIU/l) significantly (P < 0·05) decreased after a 4‐month course of metformin treatment (1·7 mIU/l, range = 0·5–5·2 mIU/l). No significant change in the serum levels of FT4 was observed in these patients. The TSH‐lowering effect of metformin was not related to the administered dose of the drug, which was similar in euthyroid as compared with hypothyroid patients with PCOS (1406 ± 589 vs 1322 ± 402 mg/day, respectively; NS). Conclusions These results indicate that metformin treatment has a TSH‐lowering effect in hypothyroid patients with PCOS, both treated with l ‐thyroxine and untreated.     

Role of ovary and adrenal glands in hyperandrogenemia in patients with polycystic ovary syndrome.

Ovary is the main source of the hyperandrogenism in polycystic ovary syndrome (PCOS). Adrenal glands may also be involved in the pathogenesis of the development of PCOS. To investigate this possibility and to find out if buserelin test is able to distinguish PCOS patients from the patients with idiopathic hirsutism (IH), ACTH and buserelin tests were performed in 29 women with PCOS, 21 women with IH, and 20 control subjects (CS). We also aimed to determine the role of dysregulation of 17 hydroxylase in the development of PCOS. Basal and stimulated dehydroepiandrosterone sulfate (DHEA-S) and stimulated cortisol (F) levels after ACTH administration were significantly higher in PCOS group than in IH and CS groups (p<0.0001 and p<0.05, respectively). PCOS patients also possessed significantly higher basal and stimulated 17-hydroxyprogesterone (17-OH P) levels, including the peak levels (p<0.02), during buserelin testing when compared with IH patients and CS. There was no significant correlation between the ACTH-stimulated and the buserelin-stimulated peak 17-OH P values. In conclusion, significantly higher basal and ACTH-stimulated levels of F and DHEA-S in PCOS compared with controls and patients with IH, reflect that adrenal hyperactivity also plays a role in hyperandrogenemia seen in PCOS. Because of the lack of the correlation between ACTH-stimulated and buserelin-stimulated 17-OH P levels, it is hard to say that adrenal hyperactivity seen in PCOS is the result of the dysregulation of cytochrome P450c17-alpha enzyme. Our results suggest that buserelin test which is an GnRH analogue could distinguish at least some of the patients with PCOS from the other patients presenting with the common symptoms of hyperandrogenemia.     

未发现多囊样卵巢的多囊卵巢综合征的临床特征

选择2004年9月至2006年10月在本中心就诊的多囊卵巢综合征(PCOS)患者876例,根据B超检查分为两组:多囊样卵巢组800例,无多囊样卵巢组76例.结果 发现无多囊样卵巢组多毛评分、睾酬、胆固醇和低密度脂蛋白明显高于多囊样卵巢组,差异有统计学意义.无多囊样卵巢组一级亲属中糖尿病、高血压病史的患病率明显增高.     

Assessment and management of anovulatory infertility in polycystic ovary syndrome.

PCOS is the most common cause of anovulatory infertility. Anovulation in PCOS is exacerbated by weight gain and improved by calorie restriction in overweight subjects. Fertility can usually be restored by appropriate choice of induction of ovulation, but careful monitoring is required, even when using clomiphene alone.     

Hypertension in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with multiple cardiovascular risk factors. The aims of this study are to investigate the prevalence of hypertension in a female population with PCOS and to correlate hypertension with her clinical and hormonal profile. MATERIALS AND METHODS: it is a transversal study of 79 PCOS patients with mean age of 25 +/- 7 years (range 13-44). PCOS diagnosis is made by Rotterdam consensus criteria's (2003). WHO definition of hypertension is used (BP 140/90 mmHg). Blood pressure is measured three times in each patient. Ovarian echography and biochemical assays (GnRH test, androgens, cholesterol, triglycerides, and oral glucose tolerance test) are made before the 5th day of the menstrual cycle. RESULTS: 12% of PCOS women have hypertension. Family history of hypertension is not a predictive factor of hypertension in our study. PCOS patients with hypertension are not significantly older than those without hypertension (28.4 +/- 6.5 vs. 25.2 +/- 7; p = 0.12). If compared to PCOS women without hypertension, those with hypertension have a significantly higher BMI (39.2 +/- 7 vs. 29.6; p = 0.0004). PCOS patients with and without hypertension do not differ significantly in their level of androgens and total cholesterol. Triglycerides level is higher in PCOS patients with hypertension (p = 0.06). In oral glucose tolerance test, areas under the curve of insulin and glucose are significantly higher in PCOS patients with hypertension (respectively p = 0.06 and 0.02). The area under the curve of LH during GnRH test is lower in PCOS patients with hypertension (p = 0.04).     

Prevalence of abnormalities of glucose metabolism in patients with polycystic ovary syndrome

Patients with polycystic ovary syndrome (PCOS) present a higher risk for abnormalities of glucose metabolism (AGM). For to study this in our population, we submitted 85 patients, with body mass index (BMI) of 28.5 +/- 6.6 kg/m(2) and aged 25.5 +/- 5.4 years old, to an oral glucose tolerance test (OGTT), and assessed the impact of BMI on the prevalence of impaired glucose tolerance (IGT) and of diabetes mellitus (DM). The states of glucose tolerance were classified considering fasting plasma glucose (FPG) according to the American Diabetes Association (ADA) criterion and plasma glucose at 120 minutes according to the Word Health Organization (WHO) criterion. According to the ADA criteria, 83.5% classified as normal and 16.5% as with AGM, with 15.3% presenting impaired fasting glucose and 1.2% DM, while according to the WHO criteria, 68.2% were classified as normal and 31.8% as with AGM, with 27.0% of them presenting IGT and 4.8% DM. Seventy-three percent of PCOS patients with IGT by WHO criterion had normal FPG by ADA criterion. The prevalence of AGM for both criteria increased with the body mass index. In conclusion, we found a higher prevalence of AGM in PCOS patients than that found in the general population, being the highest in obese patients. Glycemia at 120 minutes on the OGTT identified more patients with AGM than fasting glycemia. We recommended that the assessment of AGM must be done by the OGTT in all patients with PCOS.     

二甲双胍在多囊卵巢综合征患者妊娠期的应用

二甲双胍通过改善胰岛素抵抗（IR）、降低雄激素水平、调节脂代谢等作用,调节多囊卵巢综合征（PCOS）患者月经周期、促进排卵、减轻体重,从而增加妊娠率,在临床治疗中广泛应用.PCOS患者妊娠后由于IR加重,面临妊娠早期流产、妊娠糖尿病（GDM）、妊娠高血压及子痫前期等不良并发症,二甲双胍能减少PCOS患者妊娠早期流产、延缓GDM的发生,且对胎儿结局及出生后生长发育无明显影响.     

多囊卵巢综合征患者对ACTH反应的差异及其机制探讨

目的 观察多囊卵巢综合征(PCOS)患者ACTH兴奋试验后17羟孕酮(17OHP)的不同反应,及其与21羟化酶(CYP21)启动子区单核苷酸多态性的关系,初步探讨PCOS患者肾上腺源性高雄激素的产生机制.方法 对30名正常女性和101例PCOS患者进行ACTH兴奋试验,将PCOS患者分为高反应组(HR-PCOS)和正常反应组(NR-PCOS).比较两亚组基本情况、激素水平.对其中87例PCOS患者和30名正常女性进行CYP21启动子区-710 bp-1 bp测序,了解其单核苷酸多态性与ACTH兴奋后17OHP水平之间的关系.结果 在101例PCOS患者中,21例(20.8%)ACTH兴奋试验后17OHP水平高于正常,为HR-PCOS组;其余80例(79.2%)反应正常,为NR-PCOS组.HR-PCOS组血清总睾酮水平高于NR-PCOS组(P<0.05),NR-PCOS组高于对照组(P<0.01).HR-PCOS组基础17OHP、硫酸脱氢表雄酮(DHEAS)和兴奋后17OHP、DHEAS均显著高于NR-PCOS组和对照组(均P<0.05),NR-PCOS组与对照组之间没有差异.CYP21启动子区-535 C>T与17OHP高反应有关,-535位点的基因型与兴奋后170HP水平存在较好的相关性(r=0.20,P=0.03).其少见基因型(T/T型)和等位基因型T在高反应组中多见(P<0.05或P<0.01).该位点等位基因存在T者,发生17OHP高反应的相对危险度为3.69(95%CI 1.69～8.06).结论 约有20%PCOS患者ACTH兴奋试验后17OHP反应增高,并伴有血清总睾酮、肾上腺源性雄激素增高,提示PCOS患者17OHP对ACTH兴奋试验的高反应可能是肾上腺源性高雄激素产生的机制之一.CYP21A2启动子区-535位点的基因变异与17OHP对ACTH兴奋试验的反应性有关.     

多囊卵巢综合征患者子宫内膜非典型增生的研究进展

多囊卵巢综合征(polycystic ovary syndrome,PCOS)是与女性生殖和代谢相关的常见内分泌障碍性疾病,各种内分泌激素通过子宫内膜受体或(和)受体结合发挥作用,使PCOS患者子宫内膜可能表现为分泌期反应不良、单纯性增生、复杂性增生、不典型性增生甚至癌变等.PCOS对子宫内膜的影响机理的研究是国外近年研究的热点之一.