Hyperinsulinemia and decreased insulin-like growth factor-binding protein-1 are common features in prepubertal and pubertal girls with a history of premature pubarche

High frequency of autoimmune thyroiditis in euthyroid girls with premature adrenarche

Objective

The purpose of this study was to investigate the frequency of autoimmune thyroiditis (AT) among euthyroid prepubertal girls presenting with premature adrenarche (PA). We also aimed to identify the clinical, metabolic, and endocrine profile of girls with AT and concurrent PA and compare them to girls with AT without PA, PA alone and healthy controls.

Methods

Ninety-one prepubertal girls aged 5-10 years, who attended our department for AT, PA and normal variants of growth and puberty were recruited for the study: 73 girls had PA, 6 AT without PA and 12 were referred for investigation of growth. All girls underwent clinical examination, detailed biochemical and hormonal screen. Standard dose Synachten stimulation test (SDSST) and oral glucose tolerance test (OGTT) were performed in all girls with PA. The whole study population was divided in 4 groups: Group PA-/AT+ included 6 girls with AT without PA; Group PA+/AT- PA subjects without AT; Group PA+/AT+ girls with PA and concomitant AT; Group PA-/AT- twelve healthy girls without PA nor AT (controls).

Results

Among 73 girls presenting with PA 19 had AT (26%). BMI, systolic blood pressure (SBP) and the presence of goiter significantly differed between the four groups (p = 0.016, p = 0.022 and p < 0.001, respectively). When comparing hormonal parameters among the four groups significant differences were found in leptin (p = 0.007), TSH (p = 0.044), anti-TPO (p = 0.002), anti-TG (p = 0.044), IGF-BP1 (p = 0.006), Δ4-Α (p = 0.01), DHEA-S (p = <0.001), IGF-1 (p = 0.012) and IGF-BP3 (p = 0.049) levels. TSH levels were significantly higher in Group PA+/AT+ compared to PA+/AT- and PA-/AT- (p = 0.043 and p = 0.016, respectively). Moreover, girls with AT (Groups PA-/AT+ and PA+/AT+) had higher TSH levels than those in Group PA+/AT- (p = 0.025). Girls in Group PA+/AT + showed higher cortisol response at 60 min post-SDSST than girls in Group PA+/AT- (p = 0.035). During the OGTT, insulin concentrations at 60 min were significantly higher in Group PA+/AT + compared to Group PA+/AT- (p = 0.042).

Conclusion

A high frequency of AT among euthyroid prepubertal girls with PA was observed. The combination of PA with AT even in euthyroid state may be associated with a greater degree of insulin resistance, than PA alone.

A brief insight into the etiology, genetics, and immunology of polycystic ovarian syndrome (PCOS)

Polycystic ovarian syndrome (PCOS) is a prevailing endocrine and metabolic disorder occurring in about 6-20% of females in reproductive age. Most symptoms of PCOS arise early during puberty. Since PCOS involves a combination of signs and symptoms, thus it is considered as a heterogeneous disorderliness. The most accepted diagnostic criteria is Rotterdam criteria which involves two of the latter three features: (a) hyperandrogenism, (b) oligo- or an-ovulation, and (c) polycystic ovaries. The persistent hormonal imbalance leads to multiple small antral follicles formation and irregular menstrual cycle, ultimately causing infertility among females. Insulin resistance, cardiovascular diseases, abdominal obesity, psychological disorders, infertility, and cancer are also related to PCOS. These pathophysiologies associated with PCOS are interrelated with each other. Hyperandrogenism causes insulin resistance and hyperglycemia, leading to ROS formation, oxidative stress, and abdominal adiposity. In consequence, inflammation, ROS production, insulin resistance, and hyperandrogenemia also increase. Elevation of AGEs in the body either produced endogenously or consumed from diet exaggerates PCOS symptoms and is also related to ovarian dysfunction. This review summarizes how AGE formation, inflammation, and oxidative stress are significantly essential in PCOS progression. Alterations during prenatal development like exposure to excess AMH, androgens, or toxins (bisphenol-A, endocrine disruptors, etc.) may also be the etiologic mechanism behind PCOS. Although the etiology of this disorder is unclear, environmental and genetic factors are primarily involved. Physical inactivity, as well as unhealthy eating habits, has a vital role in the progression of PCOS. This review outlines a collection of specific genes phenotypically linked with PCOS. Furthermore, beneficial effect of metformin in maintaining endocrine abnormalities and ovarian function is also mentioned. Kisspeptin is a protein which helps in onset of puberty and increases GnRH pulsatile release during ovulation as well as role of KNDy neurons in GnRH pulsatile signal required for reproduction are also elaborated. This review also focuses on the immunology related to PCOS involving chronic low-grade inflammation, and how the alterations within the follicular microenvironment are intricated in the development of infertility in PCOS patients. How PCOS develops following antiepileptic and psychiatric medication is also expanded in this review. Initiation of antiandrogen treatment in early age (≤ 25 years) might be helpful in spontaneous conception in PCOS women. The role of BMP (bone morphogenetic proteins) in folliculogenesis and their expression in oocytes and granulosa cells are also explained. GDF8 and SERPINE1 expression in PCOS is given in detail.

NMR-based metabolic profiling of children with premature adrenarche

INTRODUCTION

Premature adrenarche (PA) for long time was considered a benign condition but later has been connected to various diseases in childhood and adulthood which remains controversial.

OBJECTIVE

To investigate the effect of premature adrenarche on the metabolic phenotype, and correlate the clinical and biochemical data with the metabolic profile of children with PA.

METHODS

Nuclear magnetic resonance (NMR)-based untargeted and targeted metabolomic approach in combination with multivariate and univariate statistical analysis applied to study the metabolic profiles of children with PA. Plasma, serum, and urine samples were collected from fifty-two children with Idiopathic PA and forty-eight age-matched controls from the division of Pediatric Endocrinology of the University Hospital of Patras were enrolled.

RESULTS

Metabolomic results showed that plasma and serum glucose, myo-inositol, amino acids, a population of unsaturated lipids, and esterified cholesterol were higher and significantly different in PA children. In the metabolic profiles of children with PA and age-matched control group a gradual increase of glucose and myo-inositol levels was observed in serum and plasma, which was positively correlated their body mass index standard deviation score (BMI SDS) values respectively. Urine ¹H NMR metabolic fingerprint of PA children showed positive correlation and a clustering-dependent relationship with their BMI and bone age (BA) respectively.

CONCLUSION

This study provides evidence that PA driven metabolic changes begin during the childhood and PA may has an inductive role in a BMI-driven increase of specific metabolites. Finally, urine may be considered as the best biofluid for identification of the PA metabolism as it reflects more clearly the PA metabolic fingerprint.

Association of dehydroepiandrosterone sulfate, birth size, adiposity and cardiometabolic risk factors in 7-year-old children

BACKGROUND

Low birth size (BS) and obesity have been associated with higher dehydroepiandrosterone sulfate (DHEAS) levels in childhood, insulin acting as a mediator, despite contradictory findings. To further explore these issues, we studied the associations between DHEAS, BS, adiposity, maternal characteristics, and cardiometabolic risk indicators, in participants of Generation XXI, a population-based birth cohort.

METHODS

A sample of 700 children (mean age 7.1 yr) was randomly selected. Data on maternal characteristics, BS, body mass index (BMI), waist-to-height ratio, body fat (dual-energy X-ray absorptiometry), insulin, lipid profile, and high-sensitivity C-reactive protein were analyzed in relation to DHEAS.

RESULTS

DHEAS was negatively associated with BS and positively associated with all adiposity indicators, with no sex differences. DHEAS was positively associated with insulinemia independently of the child's BS or BMI. No significant association was found between DHEAS, maternal characteristics, lipid profile, or high-sensitivity C-reactive protein. Including insulin in the model did not affect the association between BS and DHEAS but reduced the magnitude of the BMI effect by 24% for boys and 30% for girls.

CONCLUSION

Higher DHEAS levels at 7 years old were associated with lower BS and higher adiposity. DHEAS levels were positively associated with insulinemia independently of BS or BMI.

IMPACT

Low birth weight and obesity have been associated with higher dehydroepiandrosterone sulfate (DHEAS) levels in prepuberty. Insulin has been suggested as a mediator, despite previous studies failing to show an association between DHEAS and insulin levels. In a randomly selected population of 700 7-year-old children from the Generation XXI birth cohort, higher DHEAS levels were associated with a lower birth size and higher adiposity, with no sex differences. DHEAS was positively related to insulinemia independently of the child's birth size or body mass index. No association was found between DHEAS and other cardiometabolic risk factors.

Insulin-resistance in paediatric age: Its magnitude and implications

Insulin resistance (IR) is insulin failure in normal plasma levels to adequately stimulate glucose uptake by the peripheral tissues. IR is becoming more common in children and adolescents than before. There is a strong association between obesity in children and adolescents, IR, and the metabolic syndrome components. IR shows marked variation among different races, crucial to understanding the possible cardiovascular risk, specifically in high-risk races or ethnic groups. Genetic causes of IR include insulin receptor mutations, mutations that stimulate autoantibody production against insulin receptors, or mutations that induce the formation of abnormal glucose transporter 4 molecules or plasma cell membrane glycoprotein-1 molecules; all induce abnormal energy pathways and end with the development of IR. The parallel increase of IR syndrome with the dramatic increase in the rate of obesity among children in the last few decades indicates the importance of environmental factors in increasing the rate of IR. Most patients with IR do not develop diabetes mellitus (DM) type-II. However, IR is a crucial risk factor to develop DM type-II in children. Diagnostic standards for IR in children are not yet established due to various causes. Direct measures of insulin sensitivity include the hyperinsulinemia euglycemic glucose clamp and the insulin-suppression test. Minimal model analysis of frequently sampled intravenous glucose tolerance test and oral glucose tolerance test provide an indirect estimate of metabolic insulin sensitivity/resistance. The main aim of the treatment of IR in children is to prevent the progression of compensated IR to decompensated IR, enhance insulin sensitivity, and treat possible complications. There are three main lines for treatment: Lifestyle and behavior modification, pharmacotherapy, and surgery. This review will discuss the magnitude, implications, diagnosis, and treatment of IR in children.

Predictive factors of polycystic ovary syndrome in girls with precocious pubarche

OBJECTIVE

The aim of this study is to clarify, in girls with premature pubarche (PP), the influence of premature androgenization on the prevalence of polycystic ovary syndrome (PCOS).

DESIGN AND PATIENTS

Ninety-nine PP girls, 63 who developed PCOS and 36 who did not develop PCOS, were retrospectively included. Clinical, anthropometric, and metabolic parameters were evaluated at the time of diagnosis of PP and after 10 years from menarche to find predictive factors of PCOS.

RESULTS

Young females with PP showed a PCOS prevalence of 64% and showed a higher prevalence of familial history of diabetes (P = 0.004) and a lower prevalence of underweight (P = 0.025) than PP-NO-PCOS. In addition, girls with PP-PCOS showed higher BMI (P < 0.001), waist circumference (P < 0.001), total testosterone (P = 0.026), visceral adiposity index (VAI) (P = 0.013), total cholesterol (P < 0.001), LDL-cholesterol (P < 0.001), non-HDL cholesterol (P < 0.001) and lower age of menarche (P = 0.015), ISI-Matsuda (P < 0.001), DIo (P = 0.002), HDL cholesterol (P = 0.026) than PP-NO-PCOS. Multivariate analysis showed that WC (P = 0.049), ISI-Matsuda (P < 0.001), oral disposition index (DIo) (P < 0.001), VAI (P < 0.001), total testosterone (P < 0.001) and LDL-cholesterol (P < 0.001) are independent predictive factors for PCOS in girls with PP.

CONCLUSIONS

Our study established a strong association between multiple risk factors and development of PCOS in PP girls. These risk factors are predominantly related to the regulation of glucose, lipid, and androgen metabolism. Among these factors, WC, ISI-Matsuda, DIo, VAI, total testosterone, and LDL-cholesterol predict PCOS.

Polycystic Ovary Syndrome: Ontogeny in Adolescence

The pathophysiology of symptomatic polycystic ovary syndrome (PCOS) often unfolds across puberty, but the ontogeny of PCOS is difficult to study because, in general, its pathophysiology is well entrenched before the diagnosis can be confirmed. However, the study of high-risk groups (daughters of women with PCOS, girls with premature pubarche, and girls with obesity) can offer insight in this regard. Available data support the hypothesis that the pubertal development of PCOS involves various combinations of genetic predisposition, intrauterine programming, hyperinsulinism, and numerous other abnormalities that provoke reproductive symptoms (eg, hyperandrogenism, ovulatory dysfunction) in response to the pubertal increase in gonadotropin secretion.

The Role of Fetal, Infant, and Childhood Nutrition in the Timing of Sexual Maturation

Puberty is a crucial developmental stage in the life span, necessary to achieve reproductive and somatic maturity. Timing of puberty is modulated by and responds to central neurotransmitters, hormones, and environmental factors leading to hypothalamic-pituitary-gonadal axis maturation. The connection between hormones and nutrition during critical periods of growth, like fetal life or infancy, is fundamental for metabolic adaptation response and pubertal development control and prediction. Since birth weight is an important indicator of growth estimation during fetal life, restricted prenatal growth, such as intrauterine growth restriction (IUGR) and small for gestational age (SGA), may impact endocrine system, affecting pubertal development. Successively, lactation along with early life optimal nutrition during infancy and childhood may be important in order to set up timing of sexual maturation and provide successful reproduction at a later time. Sexual maturation and healthy growth are also influenced by nutrition requirements and diet composition. Early nutritional surveillance and monitoring of pubertal development is recommended in all children, particularly in those at risk, such as the ones born SGA and/or IUGR, as well as in the case of sudden weight gain during infancy. Adequate macro and micronutrient intake is essential for healthy growth and sexual maturity.

11-Oxygenated androgens in health and disease

The adrenal gland is a source of sex steroid precursors, and its activity is particularly relevant during fetal development and adrenarche. Following puberty, the synthesis of androgens by the adrenal gland has been considered of little physiologic importance. Dehydroepiandrosterone (DHEA) and its sulfate, DHEAS, are the major adrenal androgen precursors, but they are biologically inactive. The second most abundant unconjugated androgen produced by the human adrenals is 11β-hydroxyandrostenedione (11OHA4). 11-Ketotestosterone, a downstream metabolite of 11OHA4 (which is mostly produced in peripheral tissues), and its 5α-reduced product, 11-ketodihydrotestosterone, are bioactive androgens, with potencies equivalent to those of testosterone and dihydrotestosterone. These adrenal-derived androgens all share an oxygen atom on carbon 11, so we have collectively termed them 11-oxyandrogens. Over the past decade, these androgens have emerged as major components of several disorders of androgen excess, such as congenital adrenal hyperplasia, premature adrenarche and polycystic ovary syndrome, as well as in androgen-dependent tumours, such as castration-resistant prostate cancer. Moreover, in contrast to the more extensively studied, traditional androgens, circulating concentrations of 11-oxyandrogens do not demonstrate an age-dependent decline. This Review focuses on the rapidly expanding knowledge regarding the implications of 11-oxyandrogens in human physiology and disease.

The Unique Role of 11-Oxygenated C19 Steroids in Both Premature Adrenarche and Premature Pubarche

INTRODUCTION

Recent studies have shown 11-oxygenated androgens (11oAs) are the dominant androgens in premature adrenarche (PA). Our objective was to compare 11oAs and conventional androgens in a well-defined cohort of children with PA or premature pubarche (PP) and correlate these androgens with metabolic markers.

METHODS

A prospective cross-sectional study was conducted at a university hospital. Fasting early morning serum steroids (including 11oAs) and metabolic biomarkers were compared and their correlations determined in children ages 3-8 years (F) or 3-9 years (M) with PA or PP (5 M and 15 F) and healthy controls (3 M and 8 F).

RESULTS

There were no differences between PA, PP, and controls or between PA and PP subgroups for sex, BMI z-score, or criteria for childhood metabolic syndrome. Dehydroepiandrosterone sulfate (DHEAS) was elevated only in the PA subgroup, as defined. 11oAs were elevated versus controls in PA and PP although no differences in 11oAs were noted between PA and PP. Within the case cohort, there was high correlation of T and A4 with 11-ketotestosterone and 11β-hydroxyandrostenedione. While lipids did not differ, median insulin and HOMA-IR were higher but not statistically different in PA and PP.

CONCLUSIONS

PA and PP differ only by DHEAS and not by 11oAs or insulin sensitivity, consistent with 11oAs - rather than DHEAS - mediating the phenotypic changes of pubarche. Case correlations suggest association of 11oAs with T and A4. These data are the first to report the early morning steroid profiles including 11oAs in a well-defined group of PA, PP, and healthy children.

Interpretation of androgen and anti-Mullerian hormone profiles in a Hispanic cohort of 5- to 8-year-old girls with premature adrenarche

PURPOSE

Premature adrenarche (PA) often leads to polycystic ovary syndrome (PCOS). Higher anti-mullerian hormone (AMH) levels are reported in PCOS. We studied the androgen profile and AMH profiles in Hispanic girls with PA (aged 5-8 years) and age and body mass index (BMI) matched controls.

METHODS

Retrospective review of electronic medical records of girls who met the inclusion criteria for premature adrenarche were done.

RESULTS

PA girls (n=76) were matched to control girls (n=12) for age (mean±standard deviation) (6.7±1 years vs. 6.2±1.3 years) and BMI (20±10 kg/m2 vs. 17.8±2.7 kg/m2). Dehydroepiandrostenedione sulfate (63.3±51.3 μg/dL vs. 29.8±17.3 μg/dL, P&lt;0.001) and testosterone levels (11.4±4.8 ng/dL vs. 8.2±2.9 ng/dL, P=0.001) were significantly higher in the PA group than controls. AMH values (&lt;14 years: reference range, 0.49-3.15 ng/mL) were 3.2±2.2 ng/mL vs. 4.6± 3.2 ng/mL respectively in the PA and control groups and were not different (P=0.4). AMH did not show a correlation with bone age (P=0.1), and testosterone (P=0.9) in the PA group. 17-hydroxyprogesterone levels (17-OHP ng/dL) were 39.5±30.5 ng/dL vs. 36.8±19.8 ng/dL in PA versus control girls. The concentration of 17-OHP was not statistically different between the control and PA groups.

CONCLUSION

Higher AMH was not observed in PA girls and no correlation with BA and androgen levels was observed.

Roles of Oxidative Stress in Polycystic Ovary Syndrome and Cancers

Oxidative stress (OS) has received extensive attention in the last two decades, because of the discovery that abnormal oxidation status was related to patients with chronic diseases, such as diabetes, cardiovascular, polycystic ovary syndrome (PCOS), cancer, and neurological diseases. OS is considered as a potential inducing factor in the pathogenesis of PCOS, which is one of the most common complex endocrine disorders and a leading cause of female infertility, affecting 4%–12% of women in the world, as OS has close interactions with PCOS characteristics, just as insulin resistance (IR), hyperandrogenemia, and chronic inflammation. It has also been shown that DNA mutations and alterations induced by OS are involved in cancer pathogenesis, tumor cell survival, proliferation, invasion, angiogenesis, and so on. Furthermore, recent studies show that the females with PCOS are reported to have an increasing risk of cancers. As a result, the more serious OS in PCOS is regarded as an important potential incentive for the increasing risk of cancers, and this study aims to analyze the possibility and potential pathogenic mechanism of the above process, providing insightful thoughts and evidences for preventing cancer potentially caused by PCOS in clinic.

The Diagnosis of Polycystic Ovary Syndrome during Adolescence

BACKGROUND/AIMS

The diagnostic criteria for polycystic ovary syndrome (PCOS) in adolescence are controversial, primarily because the diagnostic pathological features used in adult women may be normal pubertal physiological events. Hence, international pediatric and adolescent specialty societies have defined criteria that have sufficient evidence to be used for the diagnosis of PCOS in adolescents.

METHODS

The literature has been reviewed and evidence graded to address a series of questions regarding the diagnosis of PCOS during adolescence including the following: clinical and biochemical evidence of hyperandrogenism, criteria for oligo-anovulation and polycystic ovary morphology, diagnostic criteria to exclude other causes of hyperandrogenism and amenorrhea, role of insulin resistance, and intervention.

RESULTS AND CONCLUSION

Features of PCOS overlap normal pubertal development. Hence, caution should be taken before diagnosing PCOS without longitudinal evaluation. However, treatment may be indicated even in the absence of a definitive diagnosis. While obesity, insulin resistance, and hyperinsulinemia are common findings in adolescents with hyperandrogenism, these features should not be used to diagnose PCOS among adolescent girls. © 2015 S. Karger AG, Basel.

Childhood environment influences adrenarcheal timing among first-generation Bangladeshi migrant girls to the UK

Background

Adrenarche is a key early life event that marks middle childhood at approximately 7 years of age. Earlier work with British-Bangladeshi migrant women suggested that environmental conditions experienced before adrenarche influence adult reproductive function. We therefore investigated whether Bangladeshi children who migrate to the United Kingdom (UK) reach adrenarche earlier than non-migrants in Bangladesh or the United Kingdom.

Methods and Findings

Healthy girls, aged 5–16 years, were recruited from schools in Sylhet, Bangladesh and London, England comprising four groups: Sylhetis (n = 165), first-generation migrants to the United Kingdom (n = 42), second-generation girls (n = 162), and British girls of European origin (n = 50). Anthropometric measurements were collected together with questionnaire data for migration and socioeconomic characteristics. Saliva samples were assayed for dehydroepiandrosterone (DHEAS) using enzyme-linked immunosorbent assays. Multiple linear regressions tested for group differences in anthropometric and socioeconomic variables and DHEAS levels. Median ages at adrenarche (DHEAS>400 pg/ml) were estimated using Weibull regression models for parametric survival analysis. Hazard ratios for reaching adrenarche earlier and 95% confidence intervals (CI), both unadjusted and adjusted for anthropometric variables, were estimated from the survival analyses. First-generation migrants had a median age at adrenarche (5.3 years) that was significantly earlier than Sylheti (7.2), second-generation (7.4), and European (7.1) girls. In univariate analyses, first-generation girls reached adrenarche significantly earlier than Sylhetis [HR (CI): 2.8 (1.4–5.5]. In multivariate models, first generation girls still reached adrenarche earlier than Sylhetis after adjusting for height [HR(CI): 1.9 (0.9–4.1)] and weight [HR(CI):1.7 (0.8–3.8)], but these results were attenuated.

Conclusions

We suggest that rapid catch-up growth experienced by first generation girls during early childhood may explain their advanced adrenarche. The environmental conditions leading to an earlier adrenarche, as well as the health implications of this early transition, merit further exploration.

The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1)

The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction.

Obesity is positively associated with dehydroepiandrosterone sulfate concentrations at 7 y in Chilean children of normal birth weight

BACKGROUND

In low-birth-weight girls, obesity increases the risk of premature adrenarche and metabolic complications. However, the consistency of this association in normal-birth-weight children and its potential mediators remain unknown.

OBJECTIVES

The objectives were to assess the associations between obesity indicators and dehydroepiandrosterone sulfate (DHEAS) at 7 y of age and to evaluate the role of hormonal markers on these associations.

DESIGN

We assessed in 969 participants (6.9 y; 48% girls; all Tanner I) in the Growth and Obesity Chilean Cohort Study the associations between DHEAS and weight, BMI, waist circumference (WC), waist-to-height ratio, skinfold thickness, and percentage total fat (bioimpedance) and determined whether these associations were related to insulin, insulin-like growth factor I (IGF-I), and leptin. We also compared BMI and height growth from 0 to 7 y of age in nonobese and obese children with normal and high DHEAS (≥75th percentile) at 7 y.

RESULTS

DHEAS concentrations were similar between girls (30.3 ±1.86 μg/dL) and boys (29.4 ±1.73 μg/dL) (P > 0.05); 17.3% of children were obese (BMI-for-age z score ≥2 SD). Adiposity indicators were positively and similarly associated with DHEAS [ie, BMI, β standardized regression coefficient: 0.23 (95% CI: 0.17, 0.29); WC, β standardized regression coefficient: 0.23 (95% CI: 0.16, 0.30)]; these associations were only partially related to IGF-I and leptin. Obese children had twice the risk of high DHEAS (OR: 2.16; 95% CI: 1.51, 3.09); at 7 y, obese children with high DHEAS were fatter and more centrally obese than their counterparts (P < 0.05), although their previous growth was similar (P > 0.05). None of the results differed by sex (P > 0.05).

CONCLUSION

In children of normal birth weight, obesity is positively associated with DHEAS at 7 y of age.

Age at menarche, the leg length to sitting height ratio, and risk of diabetes in middle-aged and elderly Chinese men and women

AIMS

To evaluate the associations of age at menarche and the leg length-to-sitting-height ratio, markers of adolescent growth, with risk of diabetes in later life.

MATERIALS AND METHODS

Information from 69,385 women and 55,311 men, aged 40-74 years from the Shanghai Women's Health Study and Shanghai Men's Health Study, were included in the current analyses. Diabetes status was ascertained through biennial in person follow-up. Cox models, with age as the time scale, were used.

RESULTS

There were 2369 cases of diabetes (1831 women; 538 men) during an average of 7.3 and 3.6 years of follow-up of the women and men, respectively. In females, menarche age was inversely associated with diabetes risk after adjustment for birth cohort, education, and income (HR = 0.95, 0.92-0.98). In both genders, leg length-to-sitting-height ratio was inversely related to diabetes (HR = 0.88, 0.80-0.97 for men; HR = 0.91, 0.86-0.96 for women) after adjustment for birth cohort, education, and income. Further adjustment for adult BMI at study enrollment completely eliminated the associations of age at menarche (HR = 0.99, 0.96-1.02) and the leg length-to-sitting-height ratio (HR = 1.00, 0.91-1.10 for men; HR = 1.01, 0.96-1.07 for women) with diabetes risk.

CONCLUSIONS

Our study suggests that markers of an early age at peak height velocity, i.e. early menarche age and low leg-length-to-sitting height ratio, may be associated with diabetes risk later in life and this association is likely to be mediated through obesity.

State of the Art Review: Emerging Therapies: The Use of Insulin Sensitizers in the Treatment of Adolescents with Polycystic Ovary Syndrome (PCOS)

PCOS, a heterogeneous disorder characterized by cystic ovarian morphology, androgen excess, and/or irregular periods, emerges during or shortly after puberty. Peri- and post-pubertal obesity, insulin resistance and consequent hyperinsulinemia are highly prevalent co-morbidities of PCOS and promote an ongoing state of excess androgen. Given the relationship of insulin to androgen excess, reduction of insulin secretion and/or improvement of its action at target tissues offer the possibility of improving the physical stigmata of androgen excess by correction of the reproductive dysfunction and preventing metabolic derangements from becoming entrenched. While lifestyle changes that concentrate on behavioral, dietary and exercise regimens should be considered as first line therapy for weight reduction and normalization of insulin levels in adolescents with PCOS, several therapeutic options are available and in wide use, including oral contraceptives, metformin, thiazolidenediones and spironolactone. Overwhelmingly, the data on the safety and efficacy of these medications derive from the adult PCOS literature. Despite the paucity of randomized control trials to adequately evaluate these modalities in adolescents, their use, particularly that of metformin, has gained popularity in the pediatric endocrine community. In this article, we present an overview of the use of insulin sensitizing medications in PCOS and review both the adult and (where available) adolescent literature, focusing specifically on the use of metformin in both mono- and combination therapy.

Clinical features, investigations and management of adolescents with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is defined as chronic anovulation with evidence of hyperandrogenism, after the exclusion of secondary causes. It is commonly linked to obesity and the presence of the metabolic syndrome.

OBJECTIVES

To review the clinical features and medical assessment of adolescents referred for PCOS to gynecology or endocrinology services at The Hospital for Sick Children (Toronto, Ontario).

METHODS

A chart review was conducted of all adolescents with PCOS referred during a one-year period. Measures included clinical findings, investigations and management.

RESULTS

Forty-one adolescent girls, with a mean age +/- SD of 14.7+/-1.5 years, were reviewed. Common presenting complaints were menstrual irregularities in 35 of 41 girls (85%) and hirsutism in 28 of 41 girls (68%), with 32 of 41 adolescents (78%) having more than one complaint. The majority (31 of 38 [82%]) were overweight or obese. Features associated with the metabolic syndrome (hypertension, dyslipidemia, insulin resistance and obesity) were identified in some adolescents, but were not consistently assessed. Blood pressure was assessed in 38 adolescents, fasting plasma glucose in 27, triglycerides in 22 and cholesterol in 21. Only four of 28 adolescents (15%) who underwent pelvic ultrasound demonstrated ovarian cysts. Investigations and management differed somewhat between endocrinologists and gynecologists. Most adolescents (34 of 41 [83%]) received pharmacological treatment: oral contraceptive pill (21 of 34 [62%]); intermittent medroxyprogesterone acetate to induce withdrawal bleeding (nine of 34 [26%]); metformin (two of 34 [6%]); or oral contraceptive pill and antiandrogen (two of 34 [6%]).

CONCLUSIONS

Adolescents with PCOS are at risk of developing metabolic abnormalities. Polycystic ovaries were not a consistent finding. The most commonly prescribed treatment was the oral contraceptive pill. Greater attention should be placed on screening adolescents with PCOS for diabetes, hypertension and dyslipidemia, allowing for earlier identification and management of potentially modifiable cardiovascular risk factors.

Approach to the girl with early onset of pubic hair

Premature pubarche, or the development of pubic hair before the age of 8 in girls or 9 in boys, is most commonly caused by premature adrenarche. Adrenarche is the maturation of the adrenal zona reticularis in both boys and girls, resulting in the development of pubic hair, axillary hair, and adult apocrine body odor. Although originally thought to be a benign variant of normal development, premature adrenarche has been associated with insulin resistance and the later development of metabolic syndrome and polycystic ovary syndrome. Although further studies are needed to confirm these relationships, the case presented herein argues for periodic assessment of children at risk. Indeed, recognition of these associations may allow for early preventive measures.

Polycystic ovary syndrome in the pediatric population

Polycystic ovary syndrome (PCOS) is a common disorder characterized by hyperandrogenism and disordered gonadotropin secretion, often associated with insulin resistance. The syndrome, which modulates both hormonal and metabolic processes, is the most common endocrinopathy in reproductive-age women and increases a woman's risk of infertility, endometrial pathology, and cardiometabolic disease. As it is currently defined, PCOS most likely encompasses several distinct diseases with similar clinical phenotypes but different underlying pathophysiological processes. However, hyperandrogenism remains the syndrome's clinical hallmark. The clinical manifestations of PCOS often emerge during childhood or in the peripubertal years, suggesting that the syndrome is influenced by fetal programming and/or early postnatal events. However, given that the full clinical spectrum of PCOS does not typically appear until puberty, a "two-hit" hypothesis has been proposed: (1) a girl develops hyperandrogenism via one or more of many different potential mechanisms; (2) the preexisting hyperandrogenism subsequently disturbs the hypothalamic–pituitary–ovarian axis, resulting in ovulatory dysfunction and sustained hyperandrogenism. No consensus guidelines exist regarding the diagnosis and management of PCOS in the pediatric population; however, because the syndrome is a diagnosis of exclusion, the clinical evaluation of girls suspected of having PCOS is aimed at excluding other causes of androgen excess and menstrual dysfunction. For the syndrome's management, emphasis is placed on lifestyle and symptom-directed treatment.

Insulin resistance in children: consensus, perspective, and future directions

OBJECTIVE

Emerging data indicate that insulin resistance is common among children and adolescents and is related to cardiometabolic risk, therefore requiring consideration early in life. However, there is still confusion on how to define insulin resistance, how to measure it, what its risk factors are, and whether there are effective strategies to prevent and treat it. A consensus conference was organized in order to clarify these points.

PARTICIPANTS

The consensus was internationally supported by all the major scientific societies in pediatric endocrinology and 37 participants.

EVIDENCE

An independent and systematic search of the literature was conducted to identify key articles relating to insulin resistance in children.

CONSENSUS PROCESS

The conference was divided into five themes and working groups: background and definition; methods of measurement and screening; risk factors and consequences; prevention; and treatment. Each group selected key issues, searched the literature, and developed a draft document. During a 3-d meeting, these papers were debated and finalized by each group before presenting them to the full forum for further discussion and agreement.

CONCLUSIONS

Given the current childhood obesity epidemic, insulin resistance in children is an important issue confronting health care professionals. There are no clear criteria to define insulin resistance in children, and surrogate markers such as fasting insulin are poor measures of insulin sensitivity. Based on current screening criteria and methodology, there is no justification for screening children for insulin resistance. Lifestyle interventions including diet and exercise can improve insulin sensitivity, whereas drugs should be implemented only in selected cases.

A single nucleotide polymorphism in STK11 influences insulin sensitivity and metformin efficacy in hyperinsulinemic girls with androgen excess

OBJECTIVE

Serine-threonine kinase STK11 catalyzes the AMP-activated protein kinase complex. We tested the hypothesis that a gene variant in STK11 contributes to variation in insulin sensitivity and metformin efficacy.

RESEARCH DESIGN AND METHODS

We studied the effects of a single nucleotide polymorphism (SNP) (rs8111699) in STK11 on endocrine-metabolic and body composition indexes before and after 1 year of metformin in 85 hyperinsulinemic girls with androgen excess, representing a continuum from prepuberal girls with a combined history of low birth weight and precocious pubarche over to postmenarchial girls with hyperinsulinemic ovarian hyperandrogenism. Metformin was dosed at 425 mg/day in younger girls and 850 mg/day in older girls. STK11 rs8111699 was genotyped. Endocrine-metabolic features were assessed in the fasting state; body composition was estimated by absorptiometry.

RESULTS

Genotype effects were similar in younger and older girls. At baseline, the mutated G allele in STK11 rs8111699 was associated with higher insulin and IGF-I levels (both P < 0.005). The response to metformin differed by STK11 genotype: GG homozygotes (n = 24) had robust metabolic improvements, GC heterozygotes (n = 38) had intermediate responses, and CC homozygotes (n = 23) had almost no response. Such differences were found for 1-year changes in body composition, circulating insulin, IGF-I, free androgen index, and lipids (all P < 0.005).

CONCLUSIONS

In hyperinsulinemic girls with androgen excess, the STK11 rs8111699 SNP influences insulin sensitivity and metformin efficacy, so that the girls with the least favorable endocrine-metabolic profile improve most with metformin therapy.

Utility of early insulin response and proinsulin to assess insulin resistance

OBJECTIVE

To determine whether obesity and premature adrenarche are additive events increasing the risk of insulin resistance and beta-cell failure, using early insulin response (EIR) or the insulinogenic index and proinsulin (PI) as markers.

STUDY DESIGN

This was a prospective case-control study conducted at a tertiary care academic medical center involving 81 prepubertal, predominantly Hispanic children (34 males, 47 females), classified as lean controls (4 males, 6 females; mean age, 6.5 +/- 1.2 years; mean body mass index [BMI] z-score, 0.08 +/- 0.6), obese controls (20 males, 10 females; mean age, 7.2 +/- 1.5 years; mean BMI z-score, 2.5 +/- 0.5), lean premature adrenarche (3 males, 11 females; mean age, 7.1 +/- 1.2 years; mean BMI z-score, 0.09 +/- 0.6), and obese premature adrenarche (7 males, 20 females; mean age, 7.3 +/- 1.0; mean BMI z-score, 2.2 +/- 0.4). Fasting glucose (G(0)), insulin (I(0)), PI(0), androgen levels, insulin-like growth factor 1, insulin-like growth factor binding protein 1, and lipid levels were obtained. An oral glucose tolerance test was performed. EIR was calculated as (I(30) - I(0))/(G(30) - G(0)). Between-group differences were assessed by 2-way analysis of variance, with interactions and associations explored with correlation/regression.

RESULTS

EIR was greater in the obese subjects with and without premature adrenarche. Combined analysis of the independent variables obesity and premature adrenarche showed that the obese premature adrenarche group had the highest EIR. The obese subjects with premature adrenarche had greater fasting PI levels than their lean counterparts. The differences in fasting PI/I ratio among the groups were not statistically significant.

CONCLUSIONS

Using EIR and PI as markers to assess the risk of insulin resistance and impaired insulin secretion indicates that obese children with premature adrenarche may be at greater risk for the development of prediabetes and type 2 diabetes mellitus compared with their lean counterparts.

Metabolic and reproductive features before and during puberty in daughters of women with polycystic ovary syndrome

CONTEXT

A significant proportion of the first-degree female relatives of women with polycystic ovary syndrome (PCOS) may be at risk for developing PCOS. However, it is not known at which stage of pubertal development the hormonal and metabolic abnormalities ensue in PCOS.

OBJECTIVE

The aim of the study was to assess the reproductive and metabolic profiles of daughters of women with PCOS (PCOSd) during the peripubertal period, a stage during which the gonadal axis is activated and PCOS may become clinically manifest.

DESIGN

Ninety-nine PCOSd [30 prepubertal and 69 pubertal (Tanner II-V)] and 84 daughters of control women (Cd) (20 prepubertal and 64 pubertal) were studied. An oral glucose tolerance test, a GnRH agonist test (leuprolide acetate, 10 microg/kg sc), and a transabdominal ultrasound were performed. Gonadotropins, sex steroids, SHBG, glucose, insulin, and lipids were determined.

RESULTS

Both groups had similar chronological ages and body mass index sd scores according to Tanner stage distribution. Ovarian volume and 2-h insulin were significantly higher in PCOSd compared to Cd at all Tanner stages. In Tanner stages IV and V, basal testosterone and poststimulated LH, testosterone, and 17-hydroxyprogesterone concentrations were significantly higher in PCOSd compared to Cd.

CONCLUSIONS

Hyperinsulinemia and an increased ovarian volume are present in PCOSd before the onset of puberty and persist during pubertal development. The biochemical abnormalities of PCOS appear during late puberty. Considering the early onset and the nature of the alterations, PCOSd constitute a high-risk group for metabolic and reproductive derangements.

Body composition in premature adrenarche by structural MRI, 1H MRS and DXA

BACKGROUND

Premature adrenarche (PA) is recognized to be a possible precursor of polycystic ovarian syndrome, type 2 diabetes mellitus and cardiovascular disease. Visceral adiposity and increased intramyocellular lipid (IMCL) are associated with insulin resistance and increased risk of cardiovascular disease.

AIM

To determine whether prepubertal girls with PA have altered visceral adiposity and/or increased muscle lipid content compared to prepubertal girls without PA using proton magnetic resonance imaging (MRI) and spectroscopy (1H MRS).

PATIENTS AND METHODS

We performed total body dual energy X-ray absorptiometry (DXA) scans, MRI of the trunk, and MRS of the tibialis anterior muscle in the right calf on six girls with PA and eight prepubertal controls.

RESULTS

Amount of visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT), and VAT to SAT ratio did not differ significantly between the PA and control girls. Those with PA, however, had significantly greater IMCL than controls (p = 0.004).

CONCLUSIONS

This study adds further evidence that PA is not a benign condition, and future studies investigating early intervention with dietary and exercise counseling may help diminish potential risk for diabetes mellitus and/or cardiovascular disease.

Clinical spectrum of premature pubarche: links to metabolic syndrome and ovarian hyperandrogenism

Premature pubarche-defined as the appearance of pubic hair before age 8 years in girls and 9 years in boys-has been traditionally considered a benign entity. However, recent evidence supports the notion that premature pubarche in girls may be a forerunner of the metabolic syndrome, and may precede the development of clinical ovarian androgen excess in adolescence. This sequence seems to occur more frequently when premature pubarche was preceded by reduced fetal growth and followed by excessive postnatal catch-up in height and particularly in weight; hyperinsulinemia appears to be a key factor in the development of this sequence of events. In girls with premature pubarche and a history of a low birth weight, puberty tends to start earlier and to have a faster course, so that final height may be moderately reduced. In these girls, metformin therapy may reverse the progression to clinical ovarian hyperandrogenism, normalize body composition and excess visceral fat, and delay pubertal progression without attenuating linear growth and bone mineralization, suggesting that adult height may be improved. Long-term follow-up of these patients is needed to fully determine the ultimate effects of insulin sensitization as well as the maintenance of these benefits after discontinuation of therapy.

Breast size and risk of type 2 diabetes mellitus

BACKGROUND

Elevated waist circumference and body mass index (BMI), both traditional measures of obesity, are accepted risk factors for type 2 diabetes mellitus. Girls who are obese experience earlier onset of puberty and possibly greater breast development. We sought to evaluate whether a woman's breast size in late adolescence is associated with an increased risk of type 2 diabetes mellitus in adulthood.

METHODS

In conjunction with the ongoing Nurses' Health Study II [corrected], we conducted a prospective cohort study involving 92,106 of the participants. We assessed the risk of type 2 diabetes mellitus in relation to self-reported bra cup sizes, categorized as < or = A, B, C and > or = D cups, among participants at age 20.

RESULTS

The mean age of participants at baseline was 38.1 years. A total of 1844 new cases of type 2 diabetes mellitus arose at a mean age of 44.9 years during 886,443 person-years of follow-up. Relative to bra cup size < or = A, the respective age-adjusted hazard ratios (and 95% confidence intervals [CIs]) were 2.30 (1.99-2.66) for B cup, 4.32 (3.71-5.04) for C cup and 4.99 (4.12-6.05) for > or = D cup. Upon further adjustments for age at menarche, parity, physical activity, smoking status, diet, multivitamin use, family history of diabetes mellitus, BMI at age 18 and current BMI, the corresponding hazard ratios (and 95% CIs) were 1.37 (1.18-1.59) for B cup, 1.80 (1.53- 2.11) for C cup and 1.64 (1.34-2.01) for > or = D cup. The addition of waist circumference to this model minimally changed the hazard ratios (and 95% CIs): 1.32 (1.14-1.53) for B cup, 1.71 (1.46-2.01) for C cup and 1.58 (1.29-1.94) for > or = D cup.

INTERPRETATION

A large bra cup size at age 20 may be a predictor of type 2 diabetes mellitus in middle-aged women. Whether this relation is independent of traditional indicators of obesity remains to be determined.

Diagnosis and treatment of polycystic ovarian syndrome and insulin resistance

PCOS is a complex syndrome that includes clinical and biochemical evidence of hyperandrogenism and hyperinsulinism. Adolescents with PCOS are affected by the diagnosis with both short-term and long-term consequences. Adolescents with PCOS report lower self-esteem and quality of life, based on standard assessments, when compared with age matched peers. These young women also are concerned about future fertility, which may affect psychological well being and health behaviors. In addition, patients with PCOS are at an increased risk for development of insulin resistance, type 2 diabetes, metabolic syndrome, and cardiovascular disease. Therefore, this identified at-risk group requires rigorous evaluation, treatment and long-term counseling and management by healthcare providers.

High neutrophil count in girls and women with hyperinsulinaemic hyperandrogenism: normalization with metformin and flutamide overcomes the aggravation by oral contraception

BACKGROUND

The endocrine hallmark of polycystic ovary syndrome (PCOS) is hyperinsulinaemic hyperandrogenism; another facet of PCOS is low-grade inflammation.

METHODS

In adolescents and young women with hyperinsulinaemic hyperandrogenism (n = 118; mean age 16 years, body mass index 22 kg/m(2)), we analysed whether the PCOS-associated rise in leukocyte count is already detectable at young age and, if so, whether such elevation is lowered by metformin, flutamide-metformin, oral contraception (OC), or their combination.

RESULTS

Leukocyte count (x 1000/mm(3)) in patients was high versus controls (7.5 +/- 0.1 versus 6.4 +/- 0.1; P < 0.001) due to a rise in neutrophils (4.2 +/- 0.1 versus 3.0 +/- 0.1; P < 0.001). Randomized studies at mean ages of 12.5 years (n = 24) and 15.2 years (n = 33) demonstrated normalizing effects of metformin (850 mg/day; P < 0.001) and, respectively, metformin plus flutamide (62.5 mg/day) on neutrophil counts; in young women (18.3 years; n = 41), the neutrophil count rose further on OC monotherapy (P = 0.003), but normalized on the same OC plus flutamide-metformin (P < 0.001 versus OC alone).

CONCLUSIONS

(i) A high leukocyte count is already present in girls with hyperinsulinaemic hyperandrogenism, and this is due to a raised neutrophil count; (ii) this hyperneutrophilia is attenuated by metformin or flutamide-metformin, and is amplified by OC monotherapy; (iii) if these treatments are combined, the normalizing effect of flutamide-metformin overcomes the OC effect on neutrophil count.

Absence of hepatotoxicity after long-term, low-dose flutamide in hyperandrogenic girls and young women

BACKGROUND

Flutamide is a pure non-steroidal anti-androgen that may be hepatotoxic, when given in high-dose (750 mg/d). Low- to ultralow-doses (250-62.5 mg/day) have been recently explored in patients with Polycystic Ovary Syndrome (PCOS), and these lower doses were found to confer benefit on multiple PCOS markers. There is a need for evidence on the potential hepatotoxicity of low- and ultralow-dose flutamide therapy.

METHODS

We assessed circulating levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as markers of hepatotoxicity in a total of 190 hyperandrogenic girls and young women receiving low- or ultralow-dose flutamide because of established (n = 150) or incipient (n = 40) PCOS without obesity. Assessments were performed before start of flutamide, after 3 months, and subsequently at least twice yearly.

RESULTS

AST and ALT results were normal at baseline, and they remained so on flutamide treatment, including between 3 months and last assessment, which was after a mean time of 19 months on low- or ultralow-dose flutamide (range 3-54 months). None of the AST or ALT levels at any time during flutamide treatment was > or = 45 U/L.

CONCLUSION

We found no evidence for hepatotoxicity in 190 hyperandrogenic girls or young women receiving low- or ultralow-dose flutamide for up to 54 months. These results may represent a first step in a long process whereby the status of low- and ultralow-dose flutamide may gradually evolve from 'absence of evidence on toxicity' towards 'evidence of absence of hepatic toxicity'. Ultralow-dose flutamide may become a key component within future therapies for hyperandrogenic states in girls and young women.

Precocious pubarche is associated with SGA, prematurity, weight gain, and obesity

BACKGROUND

Perinatal stress is thought to underlie the Barker sequelae of low birth weight, of which precocious pubarche may be a manifestation.

AIMS

To explore whether prematurity as well as smallness for gestational age (SGA) predisposes to precocious pubarche, and the potential role of excess weight gain during childhood.

METHODS

Retrospective chart review of 89 children (79 girls) with precocious pubarche.

RESULTS

Sixty five per cent were overweight/obese at diagnosis, compared with 19-24% of Australian children. Thirty five per cent had a history of SGA and 24% of prematurity. Weight SDS increased from birth to diagnosis in 91% of children. The mean change in weight SDS from birth to diagnosis was greater in those who were SGA (2.8, 95% CI 2.2 to 3.4) versus AGA (1.7, 95% CI 1.3 to 2.2), with no difference in the incidence of overweight/obesity. The latter was lower among children born premature (40% versus 72% term) but was associated with a mean increase in weight of 1.3 SDS during childhood. Nine out of ten girls and boys with precocious pubarche had at least one of the three risk factors studied.

CONCLUSIONS

Both prematurity and SGA were associated with precocious pubarche, as was overweight/obesity, irrespective of size or gestation at birth. Excess weight gain in childhood may predispose to precocious pubarche in susceptible individuals.

Prepubertal girls with premature adrenarche have greater bone mineral content and density than controls

Body composition in premature adrenarche (PA) has not been described. We hypothesized that the increased adrenal androgens in PA would have a trophic effect on lean body components. We studied 14 PA subjects and 16 controls, all prepubertal Hispanic girls. The body composition parameters tested included height, weight, bone mineral density (BMD), bone mineral content (BMC), nonbone fat-free mass, total body potassium, total body water, and extracellular water. Bone age was determined in all PA subjects. Compared with controls, PA subjects had significantly higher BMC (P = 0.02) and BMD (P = 0.03) when adjusted for age, weight, height, and fat mass, but were not different in the following lean body components: fat-free mass, total body potassium, total body water, and extracellular water. There was no difference in BMD or BMC between the PA subjects with and without advanced bone age. These data suggest a specific effect of PA on bone mineral, but not on other lean body components. The absence of a correlation between bone age and bone mineral in this small group leads us to propose there are separate promoters of bone age advancement and bone mineral accrual. Candidate hormones for these processes include adrenal androgens, E, and IGF-I. The findings of this study suggest that hormonal alterations associated with PA affect bone mineral accrual and may elucidate the mechanisms involved in this process.

Relations of insulin resistance and serum concentrations of estradiol and sex hormone-binding globulin to potential breast cancer risk factors

There is a hypothesis that hyperinsulinemia or insulin resistance may be a mediator for breast cancer risk factors. On the other hand, some, but not all, of the well-known risk factors of breast cancer have been associated with serum estrogen concentrations. We assessed the relationships of potential breast cancer risk factors to indicators of insulin resistance, fasting plasma insulin concentration and homeostasis model assessment insulin resistance (HOMA-R), in 88 postmenopausal Japanese women. We also examined whether insulin resistance would explain the association of breast cancer risk factors with serum estradiol and sex hormone-binding globulin (SHBG). Information on potential breast cancer risk factors, such as demographic characteristics, smoking and drinking habits, diet, exercise, menstrual and reproductive factors, was obtained by self-administered health questionnaire including a validated semiquantitative food frequency questionnaire. Body mass index (BMI) was significantly correlated with the ratio of estradiol to SHBG (Spearman r = 0.30, P = 0.0004), fasting plasma insulin (r = 0.45) and HOMA-R (r = 0.43, P = 0.0001) after controlling for age. The correlations were still significant between BMI and estradiol / SHBG ratio (r = 0.21, P = 0.047) after controlling for fasting plasma insulin and between BMI and fasting plasma insulin (r = 0.40, P = 0. 0001) as well as HOMA-R (r = 0.38, P = 0.0003) after controlling for estradiol / SHBG ratio. There is a possibility that effect of BMI on breast cancer risk is mediated by both insulin resistance and estrogen metabolism.

Premature pubarche, ovarian hyperandrogenism, hyperinsulinism and the polycystic ovary syndrome: from a complex constellation to a simple sequence of prenatal onset

Adolescent girls with a history of premature pubarche have an increased incidence of functional ovarian hyperandrogenism [a form of polycystic ovary syndrome (PCOS)] at adolescence, which is usually associated with hyperinsulinemia and dyslipemia. The hyperinsulinemia and lipid disturbances can often be detected in the prepubertal period and throughout puberty, and are associated with an exaggerated ovarian androgen synthesis. Birthweight SD scores are lower in premature pubarche girls than in control girls, and particularly so in those girls who show hyperinsulinemia and subsequently develop ovarian hyperandrogenism. Therefore, although the mechanisms interlinking the triad of premature pubarche, hyperinsulinism and ovarian hyperandrogenism remain enigmatic, these data indicate that the triad may result, at least in part, from a common early origin, rather than from a direct interrelationship later in life.

How possible is the prevention of polycystic ovary syndrome development in adolescent patients with early onset of hyperandrogenism

The polycystic ovary syndrome has a pubertal onset, with menstrual cycle irregularities and infertility in adulthood, as well as general health hazards such as increased risk for diabetes mellitus and myocardial infarction. Thus, prevention would be important. But as specific etiological factors are not known, nor is specific intervention. In order to use long-term intervention programs in children and adolescents, particularly rigid criteria must be used regarding proven safety and efficacy. In obese subjects, weight loss is very important, having beneficial effects on most aspects of the syndrome, such as subjective symptoms, infertility, hyperinsulinemia and related metabolic aberrations, and long-term health risks. Well controlled, long-term follow-up studies are needed on the role of prepubertal hyperandrogenism, hyperinsulinemia, gonadotropins, and ovarian morphological aspects in the development of PCOS, and possibilities of prevention.