Inverse relationship between luteinizing hormone and body mass index in polycystic ovarian syndrome: investigation of hypothalamic and pituitary contributions

CONTEXT: Patients with polycystic ovarian syndrome (PCOS) have increased LH relative to FSH, but LH is modified by body mass index (BMI). OBJECTIVE: The objective of the study was to determine whether the impact of BMI on neuroendocrine dysregulation in PCOS is mediated at the hypothalamic or pituitary level. PARTICIPANTS/INTERVENTIONS/SETTING: Twenty-four women with PCOS across a spectrum of BMIs underwent frequent blood sampling, iv administration of GnRH (75 ng/kg), and sc administration of the NAL-GLU GnRH antagonist (5 microg/kg) in the General Clinical Research Center at an academic hospital. MAIN OUTCOME MEASURES: LH pulse frequency and LH response to submaximal GnRH receptor blockade were used as measures of hypothalamic function; LH response to GnRH was used as a measure of pituitary responsiveness. RESULTS: BMI was negatively correlated with mean LH, LH/FSH, and LH pulse amplitude. There was no effect of BMI on LH pulse frequency. Percent inhibition of LH was decreased in PCOS, compared with normal women (53.9 +/- 1.5 vs. 63.1 +/- 4.1, respectively; P < 0.01), suggesting an increase in the amount of endogenous GnRH, but was not influenced by BMI. Pituitary responsiveness to GnRH was inversely correlated with BMI (peak LH, R = -0.475, P < 0.02; and LH area under the curve R = -0.412, P < 0.02). CONCLUSIONS: LH pulse frequency and quantity of GnRH are increased in PCOS, but there is no influence of BMI on either marker of hypothalamic function. The pituitary response to a weight-based dose of GnRH is inversely related to BMI in PCOS. These studies suggest that the effect of BMI on LH is mediated at a pituitary and not a hypothalamic level in PCOS.     

PCOS患者血清脂联素水平与体质量指数、胰岛素抵抗的相关性探讨

目的 探讨多囊卵巢综合征(PCOS)患者血清脂联素水平与体质量指数(BMI)、胰岛素抵抗(IR)的关系.方法 选择206例PCOS患者(PCOS组)和同期收治的74例非PCOS患者(对照组),测定其BMI、血清脂联素水平;PCOS组同时测定血糖、胰岛素,计算胰岛素指数(HOMA-IR,≥1.66为IR).结果 随BMI增加,两组血清脂联素水平呈递减趋势(正常体质量>超重>肥胖);PCOS组合并糖耐量异常(IGT)者和IR者脂联素分别为(3.97±1.27)和(4.90±2.62)mg/L,明显低于无IGT者和无IR者的(6.50±3.11)和(6.82±4.40)mg/L,P<0.01.结论 PCOS患者血清脂联素水平与BMI及IR密切相关,此为更深入了解脂联素在代谢中的作用及影响因素提供了理论依据.     

Dairy consumption and body mass index: an inverse relationship

OBJECTIVE: To assess the relationship between consumption of dairy products and body mass index (BMI) in Tehranian adults. DESIGN: Cross-sectional study. SUBJECTS: A total of 462 healthy subjects (223 men and 239 women) aged over 16 y selected randomly from among participants of the Tehran Lipid and Glucose Study (TLGS). MEASUREMENTS: Dietary data were collected by means of a food frequency questionnaire for 1 y and two 24-h dietary recalls. Height and weight were measured and BMI was calculated. Physical activity was assessed by the Lipid Research Clinic (LRC) questionnaire. RESULTS: Consumption of dairy products was 3.7+/-1.0 and 2.9+/-1.2 servings per day in men and women, respectively. As the servings of dairy consumption increased per day, the proportion of normal-weight subjects rose and that of obese ones declined. As BMI increased, the proportion of subjects with lower consumption of dairy products increased, whereas that of those with higher consumption decreased. There was a significant inverse correlation between the servings of dairy consumption per day and BMI after controlling for the effect of age, physical activity, energy, carbohydrate, dietary fiber, protein and fat intake (r=-0.38, P<0.05). After adjustment for potential confounding variables, men and women in the top quartile of dairy consumption had lower chances for being overweight (OR=0.78, 95% CI=0.43-0.92 for men and OR=0.89, 95% CI=0.53-0.95 for women) and obese (OR=0.73, 95% CI=0.40-0.83 for men and OR=0.69, 95% CI=0.34-0.80 for women) compared to those in the first quartile. CONCLUSION: The results suggest an inverse relationship between dairy consumption and BMI. It is recommended that further studies address this issue by focusing on the dairy components responsible for this effect.     

Specific factors predict the response to pulsatile gonadotropin-releasing hormone therapy in polycystic ovarian syndrome

Ovulation induction is particularly challenging in patients with polycystic ovarian syndrome (PCOS) and may be complicated by multifollicular development. Pulsatile GnRH stimulates monofollicular development in women with anovulatory infertility; however, ovulation rates are considerably lower in the subgroup of patients with PCOS. The aim of this retrospective study was to determine specific hormonal, metabolic, and ovarian morphological characteristics that predict an ovulatory response to pulsatile GnRH therapy in patients with PCOS. Subjects with PCOS were defined by chronic amenorrhea or oligomenorrhea and clinical and/or biochemical hyperandrogenism in the absence of an adrenal or pituitary disorder. At baseline, gonadotropin dynamics were assessed by 10-min blood sampling, insulin resistance by fasting insulin levels, ovarian morphology by transvaginal ultrasound, and androgen production by total testosterone levels. Intravenous pulsatile GnRH was then administered. During GnRH stimulation, daily blood samples were analyzed for gonadotropins, estradiol (E(2)), progesterone, inhibin B, and androgen levels, and serial ultrasounds were performed. Forty-one women with PCOS underwent a total of 144 ovulation induction cycles with pulsatile GnRH. Fifty-six percent of patients ovulated with 40% of ovulatory patients achieving pregnancy. Among the baseline characteristics, ovulatory cycles were associated with lower body mass index (P < 0.05), lower fasting insulin (P = 0.02), lower 17-hydroxyprogesterone and testosterone responses to hCG (P < 0.03) and higher FSH (P < 0.05). In the first week of pulsatile GnRH treatment, E(2) and the size of the largest follicle were higher (P < 0.03), whereas androstenedione was lower (P < 0.01) in ovulatory compared with anovulatory patients. Estradiol levels of 230 pg/mL (844 pmol/L) or more and androstenedione levels of 2.5 ng/mL (8.7 nmol/L) or less on day 4 and follicle diameter of 11 mm or more by day 7 of pulsatile GnRH treatment had positive predictive values for ovulation of 86.4%, 88.4%, and 99.6%, respectively. Ovulatory patients who conceived had lower free testosterone levels at baseline (P < 0.04). In conclusion, pulsatile GnRH is an effective and safe method of ovulation induction in a subset of patients with PCOS. Patient characteristics associated with successful ovulation in response to pulsatile GnRH include lower body mass index and fasting insulin levels, lower androgen response to hCG, and higher baseline FSH. In ovulatory patients, high free testosterone is negatively associated with pregnancy. A trial of pulsatile GnRH therapy may be useful in all PCOS patients, as E(2) and androstenedione levels on day 4 or follicle diameter on day 7 of therapy are highly predictive of the ovulatory response in this group of patients.     

Insulin-like factor 3: a new circulating hormone related to luteinizing hormone-dependent ovarian hyperandrogenism in the polycystic ovary syndrome

CONTEXT: Insulin-like factor 3 (INSL3), a member of the relaxin-insulin family, is produced in the Leydig cells and at reduced levels in ovarian theca interna cells of antra follicles as well as in the corpora lutea and ovarian stroma. Among the factors potentially involved in the stimulation of gonadal expression of INSL3, recent data obtained in rats show an important role of LH. Ovaries from most women affected by polycystic ovary syndrome (PCOS) are characterized by hyperplasia of the theca interna and of cortical stroma and by an increased number of small antral follicles, and the majority of women with PCOS, particularly normal-weight subjects, have LH levels that are above the normal range. OBJECTIVE: The objective of this study was to investigate INSL3 circulating levels in both normal-weight and overweight-obese PCOS women and the association of INSL3 with gonadotropin and androgenic pattern and with ovarian morphology. DESIGN: This was a controlled study. SETTING: The study took place at an academic hospital. PARTICIPANTS: The participants included 44 PCOS patients (22 normal-weight and 22 overweight-obese) and 44 controls comparable for age and body weight. MAIN OUTCOME MEASURES: The main outcome measures included INSL3 serum concentrations, measured by RIA, in PCOS patients and controls and their correlation with clinical and biochemical phenotype and with ovarian morphology. RESULTS: INSL3 serum concentrations were significantly higher in PCOS patients with respect to controls (P = 0.003), particularly in normal-weight (P = 0.001) but not in overweight-obese (P = 0.312) PCOS patients. INSL3 serum concentrations were positively correlated with total and free testosterone and with LH levels in all women (total testosterone, P < 0.001; free testosterone, P = 0.001; LH, P = 0.002) as well as in PCOS patients (total testosterone, P = 0.024; free testosterone, P = 0.045; LH, P = 0.049). Moreover, in the PCOS group, INSL3 levels were related to a greater 17OH-progesterone response to buserelin (P = 0.015), an index of ovarian hyperandrogenism. Finally, in PCOS women, INSL3 levels were positively correlated with ovarian follicle number (P = 0.028). CONCLUSIONS: INSL3 could be considered a new circulating hormone related to LH-dependent ovarian hyperandrogenism, particularly in normal-weight PCOS women.     

非酒精性脂肪性肝病和多囊卵巢综合征的关系

非酒精性脂肪性肝病(NAFLD)是一种与胰岛素抵抗(insulin resistance,IR)和遗传易感密切相关的代谢应激性肝脏损伤,其病理学改变与酒精性肝病相似,以肝细胞脂肪变性和脂肪贮存为特征,但患者无过量饮酒史的综合征.疾病谱包括非酒精性单纯性脂肪肝(nonalcoholic simply fatty liver,NAFL)、非酒精性脂肪性肝炎(nonalcoholic steatohepatitis,NASH)及其相关肝硬化和肝细胞癌[1-3].近年来,NAFLD发病率呈上升趋势,成为危害全球公共健康的重要疾病之一.目前我国NAFLD的发病呈现低龄化趋势,上海、广州、香港等发达地区成人NAFLD患病率在15%左右.NAFL患者10～20年肝硬化发生率为0.6%～3.0%,而NASH患者10～15年肝硬化发生率高达15%～25%[4].     

Evidence for insulin suppression of baseline luteinizing hormone in women with polycystic ovarian syndrome and normal women

CONTEXT: In women with polycystic ovarian syndrome (PCOS), the relationship of insulin to LH secretion and responses to GnRH remains unresolved. A rigorous analytical examination of this relationship has not been performed. OBJECTIVE: Our objective was to determine the relationship of basal LH secretion and responses to GnRH, insulin, and other endocrine variables in normal and PCOS women. DESIGN: In PCOS and normal women, mean composite 12-h LH secretion was analyzed for correlating factors. LH responses to varying doses of GnRH during a fixed rate of insulin infusion and LH responses to a fixed dose of GnRH during varying doses of insulin infusion were analyzed for contributing factors. PATIENTS AND SETTING: Eighteen PCOS and 21 normal women underwent studies of frequent blood sampling and GnRH stimulation before and during insulin infusion at the General Clinical Research Center, University of California, San Diego. MAIN OUTCOME MEASURES: Group mean composite 12-h LH levels were assessed with respect to other endocrine variables. In addition, LH responses to GnRH with or without insulin infusion were assessed. RESULTS: In normal women, insulin negatively predicted mean LH. In PCOS, the combined effect of body mass index (negative) and testosterone (positive) predicted LH. The best predictor of LH was body mass index and insulin combined. Basal LH and LH responses to GnRH were unaltered by insulin infusion in normal women. These measures were reduced during insulin infusion in PCOS women. CONCLUSIONS: In PCOS, insulin infusion suppresses pituitary response to GnRH. In normal women, insulin negatively correlates with mean LH and suppresses GnRH response at a high infusion rate.     

老年高血压与体重指数关系的研究

目的 探讨体重指数（BMI）对老年人群血压水平和高血压患病率的影响。方法 对5113例老年居民采用统一表格、方法及质量控制调查得到的高血压及其危险因素调查资料，按BMl分为BMI〈18．5；18．5≤BMI〈24；24≤BMI〈28（超重组）；BMI≥28（肥胖组）四组，按年龄分为60-64；65-69；70～79；≥80四组对高血压患病率进行分析对比。结果 老年高血压患病率随BMI的上升而上升（P〈0．05），但在≥80岁老人，不同BMI老人高血压患病率间无显著性差异（P〉0．05）。正常和超重组老年人的高血压患病率各年龄段间有显著性差异，提示在〈80岁人群中，高血压患病率随年龄增长而上升。对老年人来说，BMI随年龄的增大而下降（P〈0．05）。结论 对60～79岁的老年人，高血压患病率与其BMI呈正相关；对于≥80岁的高龄老人，年龄已取代体重等诸因素成为影响高血压患病的首要因素，BMI宜控制在肥胖标准之内。     

The relationship between body mass index and per cent body fat in the severely obese

BacKGROUND: International standards define clinical obesity according to body mass index (BMI) without reference to age and gender. Recent studies among adults in the normal to mildly obese BMI ranges have shown that the relationship between BMI and per cent body fat (% fat) differs by age and gender. The extent to which age and gender affect the relationship between BMI and % fat among more severely obese individuals is less known. AIM: The aim was to examine the age-gender association between measured BMI and % fat from a large cohort of adults, including a large number of severely obese subjects (1862 with a BMI > or = 35 kg/m(2)). METHODS: BMI was computed from measured height and weight, and % fat was estimated from bioelectrical impedance in 3068 adults. Two impedance equations, the Sun equation and the Heath equation (specific to severe obesity), were used to calculate % fat. RESULTS: Average age for 991 men and 2077 women was 46 +/- 15 vs. 44 +/- 14 years respectively (p = 0.0003). The average BMI was 36 +/- 9 kg/m(2) for men and 39 +/- 10 kg/m(2) for women (p < 0.0001), with a combined gender BMI range of 19-74 kg/m(2). Using the Sun equation, average % fat was 31 +/- 8 vs. 46 +/- 8% (p < 0.0001) for all men and women respectively. With the Sun equation, age-adjusted Spearman correlations between all BMI and % fat values were r = 0.80 and r = 0.83 for men and women, respectively, but only 0.60 (n = 479) and 0.61 (n = 1383) in severely obese participants (BMI > or = 35 kg/m(2)). Using the Heath equation, only for participants with BMI > or = 35 kg/m(2), the age-adjusted Spearman correlations improved to r = 0.82 (n = 479) and r = 0.70 (n = 1383) for men and women respectively. Finally, by combining the Sun equation for subjects with BMI < 35 kg/m(2) and the Heath equation for those with BMI > or = 35 kg/m(2), correlations improved to 0.89 for men and 0.87 for women. Using these combined equations, the relationship between BMI and % fat was best fit as a linear function for men and curvilinear function (both p < 0.001) for women across the range of BMI. The % fat was approximately 10% higher for any BMI value among women vs. men even among the severely obese (p < 0.0001). CONCLUSIONS: These data that include a large cohort of severely obese individuals demonstrated a linear association between BMI and % fat for men and a curvilinear association between BMI and % fat for women when Sun and Heath equations were combined. Assuming disease risk is driven by adiposity, this study suggests a need to further explore the appropriateness of gender-specific BMI cutpoints for clinical risk assessment due to the marked difference in the BMI-per cent fat relation observed in men and women across the entire range of BMI.     

Significant inverse relationship between serum free T4 concentration and body mass index in euthyroid subjects: differences between smokers and nonsmokers

Objective There are conflicting data regarding the relationship between thyroid function and body mass index (BMI) in euthyroid subjects, and it is uncertain whether tobacco smoking modifies this relationship. The objective of this study was to examine the relationships between thyroid function, BMI and smoking in euthyroid subjects. Design Linear regression models were used to examine the relationships between serum free T4, serum TSH, BMI and smoking in a cross‐sectional, community‐based sample of 1853 euthyroid subjects in Busselton, Western Australia. Results There was a significant negative relationship between free T4 and BMI: after adjustment for age and sex, each 1 pmol/l increase in free T4 was associated with a decrease in BMI of 0·12 kg/m² (95% CI 0·06, 0·18; P < 0·001). The mean BMI ± SD of subjects in the highest quintile of free T4 concentration was 24·4 ± 3·5 kg/m², compared with 26·1 ± 3·8 kg/m² for the lowest quintile. The relationship between free T4 and BMI was statistically significant (adjusted for age and sex) in subjects who had never smoked (P = 0·001) and former smokers (P = 0·011), but not in current smokers (P = 0·77). There was no significant relationship between TSH and BMI: after adjustment for age and sex, each 1 mU/l increase in TSH was associated with an increase in BMI of 0·08 kg/m² (95% CI –0·16, 0·32; P = 0·53). Conclusions In euthyroid subjects, small differences in free T4 are associated with differences in BMI. This relationship is not present in current smokers. We speculate that this may be relevant to weight changes associated with smoking cessation.     

Sympathetic activity and body mass index contribute to blood pressure levels.

The purpose of this study was to clarify the relationships between obesity (BMI) and BP levels, leptin levels, sympathetic activity, and insulin sensitivity in a Japanese male population. In 912 young, non-diabetic, Japanese men with a wide range of BMI (16.5-33.6 kg/m2), blood pressure (BP), fasting plasma norepinephrine (NE), insulin and leptin levels were measured after an overnight fast. The cohort consisted of 603 normotensive and 309 hypertensive subjects. The study was carried out using a cross-sectional design. When the subjects were subdivided by tertile in relation to BMI, the 101 subjects in the heaviest group (BMI > 27.9 kg/m2) had a significantly higher systolic BP (p< 0.05) and pulse rate (p< 0.05) as well as higher NE (p< 0.01), insulin (p< 0.01), and leptin (p< 0.01) levels than 86 subjects in the leanest group (BMI < 22.2 kg/m2). In the whole cohort, BMI correlated with mean BP (p< 0.01), plasma NE (p< 0.05), insulin (p< 0.001) and leptin (p< 0.001). The mean BP correlated with BMI (p< 0.001), plasma NE (p< 0.01), insulin (p< 0.01) and leptin (p< 0.05). Plasma leptin levels correlated with fasting plasma insulin levels (p < 0.05), but not with plasma NE levels (NS). As analyzed by multiple regression analysis, only plasma NE (p< 0.05) and BMI (p< 0.001), but not plasma insulin levels, were significant, independent predictors of BP levels (r2=0.125, F= 10.51, p=0.0001). These results suggest that obesity (BMI) and heightened sympathetic nervous system activity contribute to BP elevation (hypertension).     

Disruption of the joint synchrony of luteinizing hormone, testosterone, and androstenedione secretion in adolescents with polycystic ovarian syndrome

The present study explores the postulate that the polycystic ovarian syndrome (PCOS) is marked by failure of physiological feedforward and feedback signaling between pituitary LH and ovarian androgens. To this end, we appraised the 3-fold simultaneous overnight release of LH (assayed by high precision immunofluorometry), testosterone (RIA), and androstenedione (RIA) in 12 an- or oligoovulatory adolescents with PCOS (mean +/- SEM age, 16.4 +/- 0.47 yr) and 10 eumenorrheic girls (age, 16.5 +/- 0.45 yr). Gynecological (postmenarchal) ages (years) were also comparable at 4.8 +/- 0.39 (PCOS) and 4.0 +/- 3.6 (control; P = NS). Body mass index and fasting serum insulin and estradiol concentrations were indistinguishable in the two study cohorts. Mean overnight serum concentrations of LH (assayed by both immunofluorometry and Leydig cell bioassay), testosterone, androstenedione, and 17alpha-hydroxyprogesterone were each elevated significantly in patients with PCOS (all P 相似文献   

The relationship between body mass index and body cell mass in African-American, Asian, and Caucasian adults

The objective of this study was to investigate the relationship between body mass index (BMI, kg/m(2)) and body cell mass (BCM) estimated from total body potassium (TBK) measured by whole body (40)K counting in healthy 284 African-Americans (AA), 269 Asians (A) and 536 Caucasians (C) aged 18-107 years and to study the effects of age, sex, and race on the relationship. Body fat and fat-free mass (FFM) were measured by dual-energy X-ray absorptiometry (DXA). There was a significant positive correlation between BCM and BMI. For a given BMI, A had lower BCM but decreased less per year of age than AA and C, and males had higher BCM than females in each ethnic group. The fraction, BCM/FFM decreased with BMI in all subgroups by race, sex, and age, and males decreased more per age and AA decrease more than A and C. Not only the BCM-BMI relationship but also BCM/FFM vs. BMI is important to health.     

Impact of insulin and body mass index on metabolic and endocrine variables in polycystic ovary syndrome

To assess the differential impact of the insulin secretory pattern and obesity on the endocrinometabolic features of the polycystic ovary syndrome (PCOS), we studied 110 PCOS women. Patients underwent a gonadotropin-releasing hormone (GnRH) test, an oral glucose tolerance test (OGTT), and basal evaluation of hormonal and biochemical parameters. Basal androgens and lipids, basal and stimulated gonadotropins, insulin, and glucose levels were measured. Patients were classified into four groups according to the body mass index (BMI) and insulin secretion: normoinsulinemic-lean ([NL] n = 24), normoinsulinemic obese ([NO] n = 24), hyperinsulinemic lean ([HL] n = 17), hyperinsulinemic obese ([HO] n = 45). HL patients showed a higher luteinizing hormone (LH) area under curve (AUC) after GnRH stimulus compared with NL patients (HL v NL, 4,285 +/- 348 v 3,377 +/- 314 IU/L x 120 min, P < .05), whereas we failed to find a statistically significant difference in a similar comparison among obese subjects (HO v NO, 3,606 +/- 302 v 3,129 +/- 602 IU/L x 120 min). A trend toward increased plasma testosterone and decreased sex hormone-binding globulin (SHBG) was found in relation to hyperinsulinemia and obesity, thus resulting in a higher free androgen index (FAI) in groups HL and NO versus NL (HL, 5.54 +/- 0.51; NO, 5.64 +/- 0.49; NL, 4.13 +/- 0.33; P < .05 and P < .01, respectively). The presence of both exaggerated insulin secretion and obesity resulted in a synergistic additive effect on the FAI in the HO group (6.81 +/- 0.34). Concerning the lipoprotein lipid profile, the NL group showed lower plasma triglyceride levels compared with the other three groups, whereas no significant differences were found for nonesterified fatty acid (NEFA) concentrations. Higher low-density lipoprotein cholesterol (LDL-C) and very-low-density lipoprotein cholesterol (VLDL-C) and lower high-density lipoprotein cholesterol (HDL-C) levels were found in the obese groups compared with the lean counterparts, whereas the same parameters did not significantly differ in a comparison between normoinsulinemic and hyperinsulinemic groups. In conclusion, our data suggest an important role of hyperinsulinemia in the LH response to a GnRH stimulus and an independent and synergistic additive effect of obesity and hyperinsulinemia on the FAI in PCOS.     

The impact of body build on the relationship between body mass index and percent body fat.

OBJECTIVE: The objective of the study was to test the hypothesis that differences in the relationship between percent body fat (%BF) and body mass index (BMI) between populations can be explained (in part) by differences in body build. DESIGN: Cross-sectional, comparative study. SUBJECTS: 120 age, gender and BMI matched Singapore Chinese, Beijing Chinese and Dutch (Wageningen) Caucasians. MEASUREMENTS: From body weight and body height, BMI was calculated. Relative sitting height (sitting height/height) was used as a measure of relative leg length. Body fat was determined using densitometry (underwater weighing) in Beijing and Wageningen and using a three-compartment model based on densitometry and hydrometry in Singapore. Wrist and knee widths were measured as indicators for frame size and skeletal mass was calculated based on height, wrist and knee width. In addition, a slenderness index (height/sum of wrist and knee width) was calculated. RESULTS: For the same BMI, Singapore Chinese had the highest %BF followed by Beijing Chinese and the Dutch Caucasians. Singaporean Chinese had a more slender frame than Beijing Chinese and Dutch Caucasians. Predicted %BF from BMI, using a Caucasian prediction formula, was not different from measured %BF in Wageningen and in Beijing, but in Singapore the formula underpredicted %BF by 4.0 +/- 0.8% (mean +/- s.e.m.) compared to Wageningen. The difference between measured and predicted %BF (bias) was related to the level of %BF and with measures of body build, especially slenderness. Correction for differences in %BF, slenderness and relative sitting height, decreased the differences between measured and predicted values compared to the Dutch group from 1.4 +/- 0.8 (not statistically significant, NS) to -0.2 +/- 0.5 (NS) in Beijing and from 4.0 +/- 0.8 (P < 0.05) to 0.3 +/- 0.5 (NS) in Singapore (all values mean +/- s.e.m.). CONCLUSIONS: The study results confirm the hypothesis that differences in body build are at least partly responsible for a different relationship between BMI and %BF among different (ethnic) groups.     

Impact of body mass index on blood pressure levels in patients with polycystic ovary syndrome

As there is controversy about the prevalence of hypertension in patients with polycystic ovary syndrome (PCOS) and, up to the present moment, no studies have evaluated the impact of body mass index (BMI) on blood pressure levels (BP) in these patients, we studied retrospectively sixty-nine patients with PCOS, with BMI of 29.0 +/- 6.7 kg/m(2) and aged 25.6 +/-5.6 yr, subdivided into three groups according to BMI (normal, overweight and obese) and evaluated regarding BP (mercury sphygmomanometer), basal hormonal profile, fasting glucose, and insulin sensitivity (HOMA-IR). Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were normal (118.1 +/- 17.0 and 74.7+/- 11.5 mmHg, respectively), with a hypertension prevalence of 20.3%. Of these patients, 78.6% were obese and 21.4% were overweight. When the groups were compared according to BMI, a significant increase in SBP and DBP was observed (higher in overweight and obese patients for SBP and higher in obese for DBP), as well as a significant progressive increase in glucose, insulin, homeostatic model assessment, and a significant progressive decline in LH levels. When the patients were subdivided as normotensive or hypertensive, a significant difference was observed only for BMI (28.2 +/- 6.1 and 34.7 +/- 8.6 kg/m(2), respectively; p = 0.007). In conclusion, we observed a significant and progressive impact of BMI on blood pressure levels in our patients with polycystic ovary syndrome.     

Pituitary and adrenal response to ovine corticotropin-releasing hormone in women with polycystic ovarian syndrome

It has been hypothesized that there is an adrenal abnormality in the polycystic ovary syndrome (PCO). This study was undertaken to examine this hypothesis in a more physiological way, by enhancing the ACTH secretion in response to ovine corticotropin releasing hormone (oCRH) injection so that adrenal androgen and glucocorticoid responsiveness to endogenous stimulation could be examined. Plasma ACTH and the ACTH and cortisol (F) response to oCRH were normal. The plasma T and dehydroepiandrosterone (DHEA) responses were also normal. The androstenedione (A) response, however, was exaggerated. This study supports the hypothesis that the adrenal gland in patients with PCO produces increased amounts of androstenedione in response to ACTH stimulation.     

The relationship between social status and body mass index in the Minnesota Heart Health Program

This study investigated relationships between social variables and body mass index (BMI) in 2465 men and 2792 women aged 25 to 74 in six upper midwestern communities. After controlling for age and cigarette smoking status, BMI was significantly related to education, income, occupation, and marital status in both men and women. SES variables tended to be inversely related to BMI, with a steeper gradient for women than for men. A curvilinear trend was noted, however, in that social status tended to be lower at both ends of weight distribution than in the middle. The relationship between marital status and BMI was also found to be curvilinear. Highest rates of marriage were in the middle portion of the weight distribution for both sexes.