Association between changes in oestradiol and follicle-stimulating hormone levels during the menopausal transition and risk of diabetes

Menopause and Diabetes Risk Along with Trajectory of β-Cell Function and Insulin Sensitivity: A Community-Based Cohort Study

BACKGROUND

The relationship between menopause and diabetes risk is unclear, with some studies indicating a weak association. This study examined changes in diabetes risk, β-cell function, and insulin sensitivity in relation to menopause.

METHODS

In this community-based cohort study, data from 6684 visits to 1224 women over a 16-year follow-up were analyzed. Diabetes risk changes were assessed in relation to the different menopausal phases: premenopausal (≥3 years before menopause), perimenopausal (2 years before to 1 year after menopause), and postmenopausal (≥2 years after menopause). Changes in β-cell function and insulin sensitivity indices were tracked, and their relationship with diabetes risk was assessed. Generalized estimating equations and linear mixed models were used, adjusting for covariates including age at menopause and obesity.

RESULTS

Diabetes incidence was 18.6% among participants. The odds ratio (OR) of diabetes increased by 1.03 times annually during the premenopausal period (OR 1.03; 95% CI 1.02-1.04) and decreased during the postmenopausal period (OR 0.96; 95% CI 0.95-0.97). The incident diabetes groups showed a decline in insulin sensitivity and β-cell function, resulting in a decrease in the disposition indices over time. A large change in insulin sensitivity, especially during the period immediately before the onset of diabetes, increased the risk of diabetes (OR 1.88; 95% CI 1.33-2.67).

CONCLUSIONS

This study indicates an increased diabetes risk during the premenopausal periods, compared with that in the postmenopausal period, independent of age at menopause and obesity. Additionally, a decrease in insulin sensitivity followed by a subsequent decrease in β-cell function depending on the time of onset was related to the risk of diabetes. These findings enhance the understanding of diabetes risk and associated changes in insulin indices in relation to menopause, emphasizing the importance of health management and diabetes prevention for women in menopausal transition.

The role of estrogen in the sex difference for the risk factors of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is a major subtype of heart failure, primarily characterized by a normal or mildly reduced left ventricular ejection fraction along with left ventricular diastolic dysfunction. Recent studies have shown that the prevalence of HFpEF is higher in women than that in men, particularly in postmenopausal women. Concurrently, it has been observed that the incidence of risk factors contributing to HFpEF (such as obesity, hypertension, diabetes, and atrial fibrillation) also notably increases post-menopause, affecting the incidence of HFpEF. This review aimed to examine the relationship between estrogen and risk factors associated with HFpEF, clarifying the underlying mechanisms through which estrogen affects these risk factors from epidemiological and pathophysiological perspectives. This review also provides a comprehensive understanding of the association between estrogen and the risk factors for HFpEF, thus helping explore potential targets for HFpEF treatment.

Estradiol impacts Müller glia and endothelial cell responses in hyperglycemic microenvironments with advanced glycation end products

Diabetic retinopathy is a leading cause of vision loss in working adults, with disproportionate impact on women with lowered estrogen. Sex hormones and their receptors are significant to neuroprotection of the inner blood-retinal barrier (iBRB), a tissue that regulates transport across the neuroretina and vasculature. Moreover, high glucose levels in diabetes lead to the formation of advanced glycation end products (AGEs), which promote inflammation and iBRB breakdown to result in vision loss. This study examined the effects of supplemental estradiol on cell reactivity and cell barrier resistance within an in vitro model of hyperglycemia. Changes in morphology and expression of reactive oxygen species were examined when cells were exposed to a hyperglycemic medium containing AGEs, with and without supplemental estradiol. Cell morphology was assessed via changes in cell area and cell shape index, while intracellular ROS levels were measured using a ROS-sensitive dye. In addition, trans endothelial resistance (TEER) assays were used to measure changes in cell barrier function in response to hyperglycemic conditions, with and without supplemental estradiol. Results show that ROS levels in Müller glia in hyperglycemic conditions significantly decreased in response to supplemental estradiol. The estradiol further increased the resistivity of Müller glia and endothelial cell barriers cultured in high glucose and AGEs. This project illustrates the restorative effects of estradiol in collective responses of cell barriers formed by endothelial cells and Müller glia.

Sex hormone-binding globulin, testosterone and type 2 diabetes risk in middle-aged African women: exploring the impact of HIV and menopause

Objectives

Sex hormone-binding globulin (SHBG) and testosterone are differentially associated with type 2 diabetes (T2D) risk. We investigated whether these associations differ by HIV and menopausal status in Black South African women living with (WLWH) and without HIV (WLWOH).

Design

Cross-sectional observational.

Methods

Eighty one premenopausal (57 WLWOH, 24 WLWH) and 280 postmenopausal (236 WLWOH, 44 WLWH) women from the Middle-Aged Soweto Cohort (MASC) completed the following measures: circulating SHBG and sex hormones, body composition (dual energy x-ray absorptiometry), oral glucose tolerance test to estimate insulin sensitivity (Matsuda index), secretion (insulinogenic index, IGI) and clearance, and beta-cell function (disposition index, DI). Dysglycaemia was defined as either impaired fasting or postprandial glucose or T2D.

Results

SHBG was higher and total and free testosterone were lower in postmenopausal WLWH than WLWOH (all p≤0.023). Irrespective of HIV serostatus, SHBG was positively associated with Matsuda index, insulin clearance and DI and inversely with HOMA-IR (all p<0.011). The association between SHBG and Matsuda index was stronger in premenopausal than postmenopausal women (p=0.043 for interaction). Free testosterone (and not total testosterone) was only negatively associated with basal insulin clearance (p=0.021), and positively associated with HOMA-IR in premenopausal and not post-menopausal women (p=0.015 for interaction).

Conclusions

We show for the first time that midlife African WLWH have higher SHBG and lower total and free testosterone than WLWOH, which corresponded to their higher beta-cell function, suggesting a putative protective effect of SHBG on T2D risk in WLWH.

Cardiovascular and physiological risk factors in women at mid-life and beyond

Cardiovascular disease (CVD) is the leading cause of death in women. After menopause, sex-specific and gender-specific factors may play an important role in increasing CVD risk, with changes in sex hormones, body fat distribution, lipid and metabolic profile, and structural and functional vascular modifications. Premature and early-onset menopause are detrimental to cardiovascular health due to the early cessation of the protective effect of endogenous estrogen. An independent association of menopause with an increased risk of CVD has been documented in early menopause (<45 years). Sex-related differences are relevant in pharmacokinetics and pharmacodynamics; different enzyme formations, drug compatibility, efficacy, and side effects vary for different sexes. Despite some progress in sex and gender research in CVD, disparities remain. Menopausal hormone therapy (MHT) is available at mid-life for symptoms of menopause and may impact cardiovascular risk. Taken early, MHT may reduce CVD morbimortality. However, this is balanced against the risk of increased thrombosis. This paper reviews physiologic changes that contribute to cardiovascular risk in postmenopausal women and discusses clinical implications. Specifically, it explores the atheroprotective effects of estrogen and MHT and the associations between menopause with lipid levels, hypertension, body composition, and diabetes for women at mid-life and beyond.

Gonadal dysfunction in women with diabetes mellitus

It is well known that both type 1 and type 2 diabetes mellitus (DM) are related to increased risk for cardiovascular (CV) and chronic kidney disease (CKD). However, besides these prominently presented complications, DM has also been associated with reproductive dysfunctions. It seems that these disorders are met in up to 40% of women with DM and consist of delayed menarche, all types of menstrual disorders, such as amenorrhea, oligomenorrhea, menstrual irregularity, as well as menorrhagia, infertility, characteristics of polycystic ovary syndrome (PCOS) and early (or rarely late) menopause. In type 1 DM (T1DM), insulin treatment, although it has reduced the rates of insulinopenic-induced hypogonadotropic hypogonadism, an entity commonly presented in many women with the disease in the past decades, when it is used in excess it can also promote hyperandrogenism. Regarding type 2 DM (T2DM), insulin resistance (IR) and hyperinsulinemia have mainly been implicated in the pathogenesis of reproductive dysfunctions, as insulin can act as gonadotropin on the theca cells of the ovary and can lead to hyperandrogenism and inhibition of proper ovulation. This review aims to detail the reproductive dysfunctions associated with DM and provide scientific data to enlighten the underlying pathogenetic mechanisms.

Follicle-Stimulating Hormone and Diabetes in Postmenopausal Women: A Systematic Review and Meta-Analysis

CONTEXT

The co-occurrence of hormonal changes during menopause and the risk of cardio-metabolic disorders has been well studied.

OBJECTIVE

We explored the association of circulating levels of follicle-stimulating hormone (FSH) with diabetes (DM) among postmenopausal women.

METHOD

In this systematic review and meta-analysis, the search was performed in PubMed, Scopus, Web of Sciences, Epistemonikos, and Cochrane Library up to September 2023. Risk of bias was assessed by Newcastle-Ottawa Quality Assessment Scale. Pooled estimates of mean differences in FSH levels were compared between postmenopausal women with and without DM. Correlations between FSH and fasting blood glucose (FBG)/insulin/homeostatic model assessment for insulin resistance (HOMA-IR) as well as pooled effect sizes with their 95% CIs for risk of DM were calculated.

RESULTS

In this study, 14 articles, including 7878 postmenopausal women, met eligibility criteria. Most of the included studies had a low/moderate risk of bias. Women with DM had significantly lower FSH levels than those without DM (standardized mean difference [SMD] -0.751 [95% CI, -1.129 to -.372], I2 = 82.46%, n = 1416). The pooled effect size for diabetes was 0.861 (95% CI, 0.740-1.001; I2 = 80.11%). The pooled risk estimate for DM based on the categorical FSH levels (high vs low) was (HR = 0.550; 95% CI, 0.356-0.850, I2 = 0). The significant inverse correlation was found between FSH levels and glycemic parameters: FBG (r= -0.285 [95% CI -0.441 to -0.113]; n = 1229), HOMA-IR (r = -0.241[-0.378 to -0.0924]; n = 1229) and insulin (r = -0.337 [-0.434 to -0.232]; n = 959)]. There were no statistically significant differences between estradiol levels among diabetic and nondiabetic groups; however, the SMD for luteinizing hormone was similar to that reported for FSH.

CONCLUSION

The available data indicated an indirect association between FSH levels and glucose disturbances among postmenopausal women, notwithstanding heterogeneity among included studies, and the complexity of various influential factors needs to be considered. Further efforts should be made to clarify the underlying mechanisms.

Menopausal Hormone Therapy in Women with Type 2 Diabetes Mellitus: An Updated Review

Menopause is accompanied by several metabolic adaptations, which are related to insulin resistance, increased total body fat mass, and central abdominal fat accumulation, predisposing women to type 2 diabetes mellitus (T2DM) development. Metabolic syndrome has a high prevalence in postmenopausal women, indicating the loss of estrogen protection on metabolic and cardiovascular health. Moreover, earlier age at menopause has been related to increased risk of T2DM. Menopausal hormone therapy (MHT) has favorable results in glucose metabolism. Indeed, it reduces the risk of T2DM in women without this condition and improves glycemic control in women with T2DM. Before MHT initiation in women with clinical indications, it is imperative to assess their cardiovascular disease (CVD) risk, using official electronic algorithms for score calculation. The latter will determine regimen, dose, and administration route of MHT. Oral estrogens are preferable in women with low CVD risk, while transdermal administration is indicated in those with moderate and high CVD risk, as the risk of stroke and venous thromboembolism (VTE) is increased with oral administration. Oral 17β-estradiol is usually preferred in women with T2DM, as this route has more beneficial effects on glucose metabolism. Oral estrogens are also suggested in perimenopausal or recently postmenopausal women with low CVD risk. Although oral estrogens have favorable effects when indicated, the risk of VTE or stroke should always be considered. Micronized progesterone, dydrogesterone, and transdermal norethisterone are the progestogens used in postmenopausal women with T2DM and intact uterus. MHT should not be initiated in women > 60 years or > 10 years in menopause, as there is an increased thromboembolic risk in women with established atherosclerosis and no additional cardiovascular benefit in women without atherosclerosis. In conclusion, MHT administration in postmenopausal women with T2DM can be safe and effective as long as the therapeutic regimen has been properly selected according to their cardiovascular, metabolic, and fracture risk.

Elevated circulating follicle stimulating hormone level is associated with dyslipidemia in male type 2 diabetes mellitus patients: A cross-sectional study

AIMS

Type 2 diabetes mellitus (T2DM) commonly combines with dyslipidemia, and both are known as the risk factors of cardiovascular events and aggravate the arteriosclerosis progression. In this study, we investigated the relationship between follicle-stimulating hormone (FSH) and lipid profiles in male T2DM patients.

MATERIALS AND METHODS

We collected clinical data of male T2DM patients in the Chinese Han population hospitalised from January 2018 to June 2020. A total of 963 patients with a mean age of 58.89 ± 12.25 years old were enroled in this study.

RESULTS

The results showed that the levels of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL)-C levels were decreased gradually from the highest quartile groups (Q4) to Q1 group relevant to luteinising hormone and FSH, and no significant difference was observed in high-density lipoprotein-C levels among Q4-Q1 groups. Sub-groups analysis showed that, with the increased FSH level, TC, TG, and LDL-C levels were increased in the elder group (40-59 years old) than those in the younger group (20-39 years old). Spearman's analysis revealed a positive correlation between FSH and the levels of TC, TG, and LDL-C (r = 0.354, r = 0.336, r = 0.312, p < 0.001, respectively). The effect of FSH is independent of the changes in total testosterone level. Multivariate analysis found that increased FSH levels (≥9.26 mIU/mL) and decreased total testosterone levels (<13.30 nmol/L) were positively correlated with high TC, TG, and LDL-Cemia (OR = 4.014, 1.565, 1.602, 1.660, 2.127, 1.322, respectively, p < 0.05).

CONCLUSIONS

Our data suggest that high serum FSH level in male T2DM patients could be a potential independent risk factor correlated with the elevated TC, TG, and LDL-C.

Sex and Sleep Disruption as Contributing Factors in Alzheimer's Disease

Alzheimer's disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.

Ethnic Differences in the Association Between Age at Natural Menopause and Risk of Type 2 Diabetes Among Postmenopausal Women: A Pooled Analysis of Individual Data From 13 Cohort Studies

OBJECTIVE

To investigate associations between age at natural menopause, particularly premature ovarian insufficiency (POI) (natural menopause before age 40 years), and incident type 2 diabetes (T2D) and identify any variations by ethnicity.

RESEARCH DESIGN AND METHODS

We pooled individual-level data of 338,059 women from 13 cohort studies without T2D before menopause from six ethnic groups: White (n = 177,674), Chinese (n = 146,008), Japanese (n = 9,061), South/Southeast Asian (n = 2,228), Black (n = 1,838), and mixed/other (n = 1,250). Hazard ratios (HRs) of T2D associated with age at menopause were estimated in the overall sample and by ethnicity, with study as a random effect. For each ethnic group, we further stratified the association by birth year, education level, and BMI.

RESULTS

Over 9 years of follow-up, 20,064 (5.9%) women developed T2D. Overall, POI (vs. menopause at age 50-51 years) was associated with an increased risk of T2D (HR 1.31; 95% CI 1.20-1.44), and there was an interaction between age at menopause and ethnicity (P < 0.0001). T2D risk associated with POI was higher in White (1.53; 1.36-1.73), Japanese (4.04; 1.97-8.27), and Chinese women born in 1950 or later (2.79; 2.11-3.70); although less precise, the risk estimates were consistent in women of South/Southeast Asian (1.46; 0.89-2.40), Black (1.72; 0.95-3.12), and mixed/other (2.16; 0.83-5.57) ethnic groups. A similar pattern, but with a smaller increased risk of T2D, was observed with early menopause overall (1.16; 1.10-1.23) and for White, Japanese, and Chinese women born in 1950 or later.

CONCLUSIONS

POI and early menopause are risk factors for T2D in postmenopausal women, with considerable variation across ethnic groups, and may need to be considered in risk assessments of T2D among women.

Association between follicle-stimulating hormone and nonalcoholic fatty liver disease in postmenopausal women with type 2 diabetes mellitus

BACKGROUND AND AIM

Follicle-stimulating hormone (FSH) was negatively associated with nonalcoholic fatty liver disease (NAFLD) in women older than 55 years old. People with obesity and diabetes had higher prevalence of NAFLD. Thus, we aimed to explore the association between FSH and NAFLD in postmenopausal women with type 2 diabetes mellitus (T2DM).

METHODS

A total of 583 postmenopausal women with T2DM with an average age of 60.22 ± 6.49 were recruited in this cross-sectional study through January 2017 to May 2021. Anthropological data, biochemical indexes, and abdominal ultrasound results were retrospectively collected. Abdominal ultrasound was used to diagnose NAFLD. FSH was measured by enzymatic immunochemiluminescence and divided into tertiles for further analysis. The logistic regression was used to assess the association of FSH with prevalent NAFLD. Likelihood ratio tests were used to assess the interactions between groups.

RESULTS

A total of 332 (56.94%) postmenopausal women had NAFLD. Compared with postmenopausal women in the lowest tertile of FSH, postmenopausal women in the highest tertile of FSH had lower prevalence of NAFLD (p < .01). After adjusting for age, diabetes duration, metabolism-related indicators, and other sex-related hormones, FSH was inversely associated with NAFLD (odds ratio: 0.411, 95% confidence intervals: 0.260-0.651, p < .001). In subgroup analysis, there were no significant interactions of FSH with strata of metabolic factors on the association of NAFLD.

CONCLUSION

FSH was negatively and independently associated with NAFLD in postmenopausal women with type 2 diabetes mellitus. It might be a potential index for screening and identifying individuals with high risk of NAFLD in postmenopausal women.

Menopause and diabetes

In the last 20 years, the prevalence of type 2 diabetes mellitus (T2DM) has tripled in adults aged 20-79 years, affecting more than 25% of people over 50 years of age and especially women during menopause. After the menopause transition, women gain weight, increasing abdominal fat and decreasing lean body mass, with a significant reduction in energy expenditure. Increased insulin resistance and hyperinsulinism characterize this period, aggravated by an increase in plasma proinflammatory cytokines and free fatty acids, and a state of relative hyperandrogenism. Previous recommendations systematically excluded women with T2DM from menopause hormone therapy (MHT); new evidence confirms that MHT significantly reduces the diagnosis of new-onset T2DM and may be beneficial in terms of glycemic control when used for menopause symptom management in patients with pre-existing T2DM. A comprehensive and individualized approach is considered the first line of management for women during this period, especially in T2DM patients or in women at risk of developing the disease. The objectives of this presentation are to review the etiopathogenic factors involved in the increased incidence of new cases of T2DM during menopause, the impact of menopause on T2DM and the role of MHT.

Exposure to heavy metals and hormone levels in midlife women: The Study of Women's Health Across the Nation (SWAN)

Exposure to heavy metals may alter the circulating levels of sex hormones. However, epidemiologic studies on heavy metals and sex hormones have been limited, and results have been inconsistent. We assessed the associations of heavy metals assayed in urine, including arsenic, cadmium, lead, and mercury, with repeated measures of serum estradiol (E2), follicle-stimulating hormone (FSH), testosterone, and sex hormone-binding globulin (SHBG) levels in the Study of Women's Health Across the Nation Multi-Pollutant Study. The sample included 1355 White, Black, Chinese, and Japanese women, aged 45-56 years at baseline (1999-2000), whose serum hormone levels were repeatedly measured through 2017. Urinary metal concentrations were measured at baseline. Linear mixed effect models were used to calculate percent changes in serum hormone levels per doubling of urinary metal concentrations, adjusting for demographics, socioeconomic status, lifestyle, health-related factors, and urinary creatinine. After multivariable adjustment, a doubling of urinary metal concentration was associated with lower E2 levels by 2.2% (95% CI: 4.0%, -0.3%) for mercury and 3.6% (95% CI: 5.7%, -1.6%) for lead; higher FSH levels by 3.4% (95% CI: 0.9%, 5.9%) for lead; and higher SHBG levels by 3.6% (95% CI: 1.3%, 5.9%) for cadmium. The overall joint effect using the Bayesian kernel machine regression showed that metal mixtures were inversely associated with E2 and positively associated with FSH levels. No association was found between metals and testosterone levels. Results from this prospective cohort study demonstrate that environmental heavy metal exposures, including cadmium, mercury, and lead, may disturb circulating levels of E2, FSH, and SHBG in midlife women.

Oral Manifestation in Postmenopausal Women of Maharashtra, Western Region

Introduction

Menopause in women is a physiological state that gives rise to adaptive changes at both the systemic and oral levels. The oral manifestations of postmenopausal women may vary for each patient. It occurs in the form of burning mouth syndrome, xerostomia, periodontitis, etc., We aimed to assess the prevalence of oral manifestations in the postmenopausal population, to know the nature and severity of oral manifestations occurring in postmenopausal women, and to assess the systemic conditions of these postmenopausal women with oral manifestations. The study was designed to assess the oral manifestation in postmenopausal women of Maharashtra, Western region.

Materials and Methods

The study was conducted in the department of oral medicine and radiology. A total of 90 patients were included. A detailed clinical examination was done using a mouth mirror and probe. The clinical pro forma recorded demographic data, including the duration of menopause and different oral manifestations like xerostomia, periodontitis, lichen planus, oral candidiasis, etc., Collected data were entered into MS Excel and subjected to statistical analysis.

Results

In the study, there were a total of 90 patients. These patients were distributed into three groups based on their age groups. The majority of the oral manifestations were reported in patients belonging to Group 2 (60-70 years age group).

Conclusion

Overall, 76.6% of patients reported oral mucosal changes; of which 20.2% of patients reported xerostomia, 15.9% reported periodontitis, 13% showed altered taste, 8.6% of patients had lichen planus, and 7.2% patients reported oral candidiasis and space infections.

Effects of Anterior Pituitary Adenomas' Hormones on Glucose Metabolism and Its Clinical Implications

Pituitary adenomas have recently become more common and their incidence is increasing yearly. Functional pituitary tumors commonly secrete prolactin, growth hormones, and adrenocorticotropic hormones, which cause diseases such as prolactinoma, acromegaly, and Cushing's disease, but rarely secrete luteinizing, follicle-stimulating, thyroid-stimulating, and melanocyte-stimulating hormones. In addition to the typical clinical manifestations of functional pituitary tumors caused by excessive hormone levels, some pituitary tumors are also accompanied by abnormal glucose metabolism. The effects of these seven hormones on glucose metabolism are important for the treatment of diabetes secondary to pituitary tumors. This review focuses on the effects of hormones on glucose metabolism, providing important clues for the diagnosis and treatment of related diseases.

The interplay between diabetes mellitus and menopause: clinical implications

The menopausal transition is an impactful period in women's lives, when the risk of cardiovascular disease is accelerated. Similarly, diabetes mellitus profoundly impacts cardiovascular risk. However, the interplay between menopause and diabetes mellitus has not been adequately studied. The menopausal transition is accompanied by metabolic changes that predispose to diabetes mellitus, particularly type 2 diabetes mellitus (T2DM), as menopause results in increased risk of upper body adipose tissue accumulation and increased incidence of insulin resistance. Equally, diabetes mellitus can affect ovarian ageing, potentially causing women with type 1 diabetes mellitus and early-onset T2DM to experience menopause earlier than women without diabetes mellitus. Earlier age at menopause has been associated with a higher risk of T2DM later in life. Menopausal hormone therapy can reduce the risk of T2DM and improve glycaemic control in women with pre-existing diabetes mellitus; however, there is not enough evidence to support the administration of menopausal hormone therapy for diabetes mellitus prevention or control. This Review critically appraises studies published within the past few years on the interaction between diabetes mellitus and menopause and addresses all clinically relevant issues, such as the effect of menopause on the development of T2DM, and the management of both menopause and diabetes mellitus.

Supplementation with omega-3 or omega-6 fatty acids attenuates platelet reactivity in postmenopausal women

Postmenopausal women are at increased risk for a cardiovascular event due to platelet hyperactivity. There is evidence suggesting that ω-3 polyunsaturated fatty acids (PUFAs) and ω-6 PUFAs have cardioprotective effects in these women. However, a mechanistic understanding of how these fatty acids regulate platelet function is unknown. In this study, we supplemented postmenopausal women with fish oil (ω-3 fatty acids) or evening primrose oil (ω-6 fatty acids) and investigated the effects on their platelet activity. The effects of fatty acid supplementation on platelet aggregation, dense granule secretion, and activation of integrin αIIbβ3 at basal levels and in response to agonist were tested in postmenopausal women following a supplementation and washout period. Supplementation with fish oil or primrose oil attenuated the thrombin receptor PAR4-induced platelet aggregation. Supplementation with ω-3 or ω-6 fatty acids decreased platelet dense granule secretion and attenuated basal levels of integrin αIIbβ3 activation. Interestingly, after the washout period following supplementation with primrose oil, platelet aggregation was similarly attenuated. Additionally, for either treatment, the observed protective effects post-supplementation on platelet dense granule secretion and basal levels of integrin activation were sustained after the washout period, suggesting a long-term shift in platelet reactivity due to fatty acid supplementation. These findings begin to elucidate the underlying mechanistic effects of ω-3 and ω-6 fatty acids on platelet reactivity in postmenopausal women. Hence, this study supports the beneficial effects of fish oil or primrose oil supplementation as a therapeutic intervention to reduce the risk of thrombotic events in postmenopausal women. https://clinicaltrials.gov/ct2/show/NCT02629497.

Estradiol (E2) Improves Glucose-Stimulated Insulin Secretion and Stabilizes GDM Progression in a Prediabetic Mouse Model

Female New Zealand obese (NZO) mice are an established model of preconceptional (pc.) prediabetes that progresses as gestational diabetes mellitus (GDM) during gestation. It is known that NZO mice show improvement in insulin sensitivity and glucose-stimulated insulin secretion (GSIS) during gestation in vivo. The latter is no longer detectable in ex vivo perifusion experiments in isolated islets of Langerhans, suggesting a modulation by extrapancreatic factors. Here, we demonstrated that plasma 17β-estradiol (E2) levels increased markedly in NZO mice during gestation. The aim of this work was to determine whether these increased E2 levels are responsible for the improvement in metabolism during gestation. To achieve this goal, we examined its effects in isolated islets and primary hepatocytes of both NZO and metabolically healthy NMRI mice. E2 increased GSIS in the islets of both strains significantly. Hepatic glucose production (HGP) failed to be decreased by insulin in NZO hepatocytes but was reduced by E2 in both strains. Hepatocytes of pregnant NZO mice showed significantly lower glucose uptake (HGU) compared with NMRI controls, whereby E2 stimulation diminished this difference. Hepatocytes of pregnant NZO showed reduced glycogen content, increased cyclic adenosine monophosphate (cAMP) levels, and reduced AKT activation. These differences were abolished after E2 stimulation. In conclusion, our data indicate that E2 stabilizes and prevents deterioration of the metabolic state of the prediabetic NZO mice. E2 particularly increases GSIS and improves hepatic glucose utilization to a lower extent.

Menopausal status, age at natural menopause and risk of diabetes in China: a 10-year prospective study of 300,000 women

BACKGROUND

Menopause characteristics have been implicated in future health consequences, yet little is known about its relevance to diabetes. We examined the associations of menopausal status and age at natural menopause with diabetes risk in Chinese women.

METHODS

We used prospective data of the China Kadoorie Biobank study that recruited 302,522 women aged 30-79 years in 2004-2008 from 10 areas across China. During average 10.8 years of follow-up, 11,459 incident diabetes cases were recorded among 281,319 women without prior diabetes diagnosis at baseline. Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for incident diabetes associated with menopausal status and age at natural menopause.

RESULTS

Overall, the mean (SD) age at natural menopause was 48.2 (4.4) years among 141,789 post-menopausal women. Naturally peri-, or post-menopausal women were at higher risk of diabetes, with HRs of 1.17 (95% CI 1.06-1.29) and 1.15 (1.06-1.25) compared with pre-menopausal women, adjusting for several potential confounders. Among women who had natural menopause, the HR of diabetes was 1.14 (1.01-1.30), 1.01 (0.93-1.09), 1.10 (1.04-1.16), and 1.10 (1.01-1.20) for menopause at ages less than 40, 40-44, 50-53, and 54 years or older, respectively, relative to 45-49 years.

CONCLUSIONS

In this study, we found that women with naturally peri-, or post-menopausal status had higher risk of developing diabetes. Besides, among the post-menopausal women, both earlier and later age at natural menopause were associated with increased risk of diabetes.

Change in metabolic parameters and reproductive hormones from baseline to 6-month hormone therapy

Adequate evidence showed hormone therapy (HT) reduces the risk of new-onset diabetes in midlife women by decreasing fasting glucose and insulin. However, the improvement of these diabetic biomarkers varied with each individual in clinical observations. The objective of our study was to investigate potential baseline factors associated with the change of fasting glucose and insulin during HT.A retrospective cohort study was performed among 263 midlife participants aged 40 to 60 years with menopausal symptoms who have received 6-month individualized HT. Demographic information and laboratory indicators including reproductive hormone, lipid profiles, diabetic indicators were collected and measured at baseline and were followed-up. A series of statistical analyses were performed to confirm the effectiveness of HT and compare the baseline factors between participants with different glycemic or insulinemic response. Multivariable linear regression model with stepwise variable selection was further used to identify the associated factor with the change of fasting glucose and insulin.Of all participants, fasting glucose (P = .001) and fasting insulin (P < .001) were significantly decreased after individualized HT. Significant differences in baseline reproductive hormones were observed in participants with different glycemic response to HT (P < .001 for both follicle stimulating hormone [FSH] and estradiol). Stepwise linear regression model showed that in addition to baseline fasting glucose levels, baseline FSH was also independently associated with the change of fasting glucose (β = -0.145, P = .019 for baseline FSH) but not fasting insulin. Greater reduction in fasting glucose in women with higher FSH levels was observed even though they have already been in better metabolic conditions (P = .037).Midlife women with higher baseline FSH levels have greater reduction in fasting glucose but not fasting insulin. FSH could be an independent predictor of glycemic response to HT in peri- and postmenopausal women.

Menopausal Hormone Replacement Therapy and Reduction of All-Cause Mortality and Cardiovascular Disease: It Is About Time and Timing

ABSTRACT

The totality of evidence indicates menopausal hormone replacement therapy (HRT) effects are determined by timing of initiation according to age and/or time since menopause, underlying health of target tissue, and duration of therapy. Initiated in women at younger than 60 years and/or at or near menopause, HRT significantly reduces all-cause mortality and cardiovascular disease (CVD), whereas other primary CVD prevention therapies such as lipid-lowering fail to do so. The magnitude and type of HRT-associated risks, including breast cancer, stroke, and venous thromboembolism, are rare (<10 events/10,000 women), not unique to HRT, and comparable with other medications. Hormone replacement therapy is a sex-specific and time-dependent primary CVD prevention therapy that concomitantly reduces all-cause mortality, as well as other aging-related diseases with an excellent risk profile. Keeping in mind that prevention strategies must be personalized, health care providers and patients can use cumulated HRT data in making clinical decisions concerning chronic disease prevention including CVD and mortality reduction.

Obesity and Risk of Diabetes Mellitus by Menopausal Status: A Nationwide Cohort Study

Although both obesity and menopause are associated with increased risk of diabetes mellitus (DM), the association between obesity and DM according to menopausal status remains uncertain. Therefore, we conducted a study to examine the relationship between obesity and incidence of diabetes mellitus (DM) in premenopausal and postmenopausal women. Total of 926,196 premenopausal and 1,193,881 postmenopausal women who underwent health examinations from 2009 to 2014 were identified using the database of the Korean National Health Insurance Service. We compared the incidence and risk of DM according to body mass index (BMI) and waist circumference (WC) in the two groups of women. Cox proportional hazards analyses were performed to evaluate the association between the presence of obesity and risk of DM according to menopausal state. During the 7.8-year follow-up period, 37,736 (4.1%) premenopausal women and 121,102 (10.1%) postmenopausal women were diagnosed with DM. Compared to the reference group (BMI 18.5-23), a stronger association between obesity and risk of DM was observed in both pre- and postmenopausal women: multivariable-adjusted hazard ratios and 95% confidence intervals for BMI subgroups <18.5, 23-25, 25-30, and >30 were 0.62 (0.54, 0.70), 1.91 (1.85, 1.97), 3.38 (3.28, 3.47), and 6.25 (6.02, 6.48), respectively (p trend < 0.001) in premenopausal women and 0.87 (0.82, 0.92), 1.44 (1.41, 1.46), 2.00 (1.97, 2.03), and 2.96 (2.89, 3.02) in postmenopausal women (p trend < 0.001, p-interaction < 0.001). A similar trend was observed for WC. Subgroup analyses of women aged 45 to 55 also showed a stronger association with DM in premenopausal than in postmenopausal women. In conclusion, the association between obesity and DM was stronger in premenopausal women than in postmenopausal women. As estrogens are synthesized in adipose tissue by aromatization of androgens after menopause, increased estrogen levels in obese postmenopausal might have a protective effect against DM.

Menopause and cardiometabolic diseases: What we (don't) know and why it matters

This narrative review discusses the current understanding, knowledge gaps and challenges in expanding our knowledge of the association between menopause and the reproductive aging process and cardiometabolic disease (CMD) in women, with a focus on type 2 diabetes and cardiovascular disease. The physiological changes that occur at different stages of the reproductive life span, as well as type of menopause and timing, are factors widely associated with CMD risk; however, the underlying mechanisms remain either unclear or insufficiently studied. Decreased ovarian estrogen production and relative androgen excess around menopause onset are the most studied factors linking menopause and cardiometabolic health; nevertheless, the evidence is not persuasive and other hypotheses might explain the changes in CMD risk during menopausal transition. In this context, hormone therapy has been widely adopted in the treatment and prevention of CMD, although uncertainty regarding its cardiometabolic effects has raised the need to optimize therapeutic modalities. Mechanisms such as the "iron overload theory" and new "omics" platforms could provide new insights into potential pathways underlying the association between menopause and cardiometabolic health, such as the DNA damage response. Although it has been widely reported that environmental and lifestyle factors affect both menopause and cardiometabolic health, there is little evidence on the role of these exposures in menopause-associated CMD risk.

Total testosterone is not associated with lean mass or handgrip strength in pre-menopausal females

The aim of this study was to examine the relationship between endogenous testosterone concentrations and lean mass and handgrip strength in healthy, pre-menopausal females. Testosterone has been positively associated with lean mass and strength in young and older males. Whether this relationship exists in pre-menopausal females is unknown. Secondary data from the 2013-2014 National Health and Nutrition Examination Survey were used to test this relationship. Females were aged 18-40 (n = 716, age 30 ± 6 years, mean ± SD) and pre-menopausal. Multivariate linear regression models were used to examine associations between total testosterone, lean mass index (LMI) and handgrip strength. Mean ± SD testosterone concentration was 1.0 ± 0.6 nmol L-1 and mean free androgen index (FAI) was 0.02 ± 0.02. In pre-menopausal females, testosterone was not associated with LMI (β = 0.05; 95%CI - 0.04, 0.15; p = 0.237) or handgrip strength (β = 0.01; 95%CI - 0.11, 0.12; p = 0.926) in a statistically significant manner. Conversely, FAI was associated with LMI (β = - 0.03; 95%CI - 0.05, - 0.02; p = 0.000) in a quadratic manner, meaning LMI increases with increasing FAI levels. Handgrip strength was not associated with FAI (β = 0.06; 95%CI - 0.02, 0.15; p = 0.137). These findings indicate that FAI, but not total testosterone, is associated with LMI in pre-menopausal females. Neither FAI nor total testosterone are associated with handgrip strength in pre-menopausal females when testosterone concentrations are not altered pharmacologically.

Ovariectomy Impaired Hepatic Glucose and Lipid Homeostasis and Altered the Gut Microbiota in Mice With Different Diets

The lower incidence of metabolic diseases of women than men and the increasing morbidity of metabolic disorders of menopausal women indicated that hormones produced by ovaries may affect homeostasis of glucose and lipid metabolism, but the underlying mechanisms remain unclear. To explore the functions of ovaries on regulating glucose and lipid metabolism in females, 8 weeks old C57BL/6 mice were preformed ovariectomy and administrated with normal food diet (NFD) or high fat diet (HFD). Six weeks after ovariectomy, blood biochemical indexes were tested and the morphology and histology of livers were checked. The expression levels of genes related to glucose and lipid metabolism in liver were detected through transcriptome analysis, qPCR and western blot assays. 16S rDNA sequence was conducted to analyze the gut microbiota of mice with ovariectomy and different diets. The serum total cholesterol (TC) was significantly increased in ovariectomized (OVX) mice fed with NFD (OVXN), and serum low density lipoprotein-cholesterol (LDL-C) was significantly increased in both OVXN mice and OVX mice fed with HFD (OVXH). The excessive glycogen storage was found in livers of 37.5% mice from OVXN group, and lipid accumulation was detected in livers of the other 62.5% OVXN mice. The OVXN group was further divided into OVXN-Gly and OVXN-TG subgroups depending on histological results of the liver. Lipid drops in livers of OVXH mice were more and larger than other groups. The expression level of genes related with lipogenesis was significantly increased and the expression level of genes related with β-oxidation was significantly downregulated in the liver of OVXN mice. Ovariectomy also caused the dysbiosis of intestinal flora of OVXN and OVXH mice. These results demonstrated that hormones generated by ovaries played important roles in regulating hepatic glucose and lipid metabolism and communicating with the gut microbiota in females.

The midlife transition and the risk of cardiovascular disease and cancer Part I: magnitude and mechanisms

Heart disease and cancer are the leading causes of death in the United States. In women, the clinical appearance of both entities-coronary heart disease and cancer (breast, endometrium, and ovary)-escalate during the decades of the midlife transition encompassing the menopause. In addition to the impact of aging, during the interval between the age of 40 and 65 years, the pathophysiologic components of metabolic syndrome also emerge and accelerate. These include visceral adiposity (measured as waist circumference), hypertension, diabetes, and dyslipidemia. Osteoporosis, osteoarthritis, sarcopenia, depression, and even cognitive decline and dementia appear, and most, if not all, are considered functionally related. Two clinical reports confirm the interaction linking the emergence of disease: endometrial cancer and metabolic syndrome. One describes the discovery of unsuspected endometrial cancer in a large series of elective hysterectomies performed in aged and metabolically susceptible populations. The other is from the Women's Health Initiative Observational Study, which found a positive interaction between endometrial cancer and metabolic syndrome regardless of the presence or absence of visceral adiposity. Both provide additional statistical support for the long-suspected causal interaction among the parallel but variable occurrence of these common entities-visceral obesity, heart disease, diabetes, cancer, and the prevalence of metabolic syndrome. Therefore, 2 critical clinical questions require analysis and answers: 1: Why do chronic diseases of adulthood-metabolic, cardiovascular, endocrine-and, in women, cancers of the breast and endometrium (tissues and tumors replete with estrogen receptors) emerge and their incidence trajectories accelerate during the postmenopausal period when little or no endogenous estradiol is available, and yet the therapeutic application of estrogen stimulates their appearance? 2: To what extent should identification of these etiologic driving forces require modification of the gynecologist's responsibilities in the care of our patients in the postreproductive decades of the female life cycle? Part l of this 2-part set of "expert reviews" defines the dimensions, gravity, and interactive synergy of each clinical challenge gynecologists face while caring for their midlife (primarily postmenopausal) patients. It describes the clinically identifiable, potentially treatable, pathogenic mechanisms driving these threats to quality of life and longevity. Part 2 (accepted, American Journal of Obstetrics & Gynecology) identifies 7 objectives of successful clinical care, offers "triage" prioritization targets, and provides feasible opportunities for insertion of primary preventive care initiatives. To implement these goals, a reprogrammed, repurposed office visit is described.

The midlife transition and the risk of cardiovascular disease and cancer Part II: strategies to maximize quality of life and limit dysfunction and disease

Chronic dysfunction, disabilities, and complex diseases such as cardiovascular disease, diabetes mellitus type 2, osteoporosis and certain cancers, among other burdens, emerge and accelerate in midlife women. Previously in part l, we described the clinical and laboratory research findings that more readily explain and clarify the underlying pathogenetic mechanisms driving these clinical burdens, including new findings on how in particular visceral obesity and the emergence and acceleration of various components of metabolic syndrome-glucotoxicity and lipotoxicity-and a chronic systemic inflammatory state abetted by the loss of ovarian production of estradiol and the inevitable inroads of aging generate this spectrum of clinical problems. These research insights translate into opportunities for effective care strategies leading to prevention, amelioration, possible correction, and enhanced quality of life. To achieve these goals, updated detailed diagnostic, management, and therapeutic guidelines implemented by a reprogrammed and repurposed "menopause" office visit are described. A triage mechanism-when to refer to other specialists for further care-is emphasized. The previously polarized views of menopausal hormone therapy have narrowed significantly, leading to the construction of a more confident, unified, and wider clinical application. Accordingly, a menopausal hormone therapy program providing maximum benefit and minimum risk, accompanied by an algorithm for enhanced shared decision making, is included.

Relationships between Follicle-Stimulating Hormone and Adiponectin in Postmenopausal Women

Beyond fertility, follicle-stimulating hormone (FSH) may exert action on adipocytes, which are the major source of adiponectin and leptin, linking to insulin resistance. Therefore, we evaluated the relationships between FSH and adipocyte-derived hormones. This cross-sectional study enrolled postmenopausal women aged 40–65 years. The variables measured in this study included clinical parameters, fasting levels of sex hormones, glucose, insulin, and adipokines. A total of 261 women without breast cancer, 88 women with breast cancer receiving tamoxifen, and 59 women with breast cancer receiving additional gonadotropin-releasing hormone analogs were enrolled in this study. Significant differences in the levels of adiponectin, leptin, and FSH were observed between the non-breast cancer group and the breast cancer groups. Spearman’s rank test revealed significant associations of FSH with either body mass index (BMI) or homeostatic model assessment of insulin resistance (HOMA-IR) values in the non-breast cancer group. After adjusting for BMI, age, and menopause duration, FSH levels were significantly associated with adiponectin (p < 0.001) and the leptin-to-adiponectin ratio (p = 0.008) in the non-breast cancer group, but they were only significantly associated with adiponectin (p = 0.001) in the breast cancer group receiving tamoxifen. Our data show that FSH levels are independently associated with adiponectin levels in postmenopausal women, suggesting that adiponectin may link FSH to metabolic relationships in postmenopausal female.

Changes in the glucose and insulin responses according to high-protein snacks for diabetic patients

BACKGROUND/OBJECTIVES

This study aimed to develop healthy, appetizing high-protein snacks with enhanced isolated soy protein for diabetic patients and determine the blood glucose and insulin response after being consumed by these patients.

MATERIALS/METHODS

Thirty adult patients aged between 30 and 75 years, with a ≤ 10-year history of type 2 diabetes and hemoglobin A1c of < 7.5%, were enrolled in this study. They made 3 clinical visits at one-week intervals. The control group consumed 50 g carbohydrates (white bread), whereas the test groups consumed high-protein grain (HP_G) or high-protein chocolate (HP_C) after an 8-hrs fast. Blood (2 cm³) was drawn at 15, 30, 45, 60, 90, and 120 min before and after consumption to analyze the blood glucose and insulin concentrations.

RESULTS

Compared to the commercial snacks, the developed high-protein snacks had below-average calorie, carbohydrate, and fat content and a 2.5-fold higher protein content. In diabetic patients who consumed these snacks, the postprandial blood glucose increased between 15 min and 2 h after consumption, which was significantly slower than the time taken for the blood glucose to increase in the patients who consumed the control food product (P < 0.001). Insulin secretion was significantly lower at 45 min after consumption (P < 0.05), showing that the high-protein snacks did not increase the blood glucose levels rapidly. The incremental area under the curve (iAUC), which indicated the degree of blood sugar and insulin elevation after food intake, was higher in the control group than the groups given the 2 developed snacks (P < 0.001), and there was no significant difference in insulin secretion.

CONCLUSIONS

The results of the postprandial blood glucose and insulin response suggest that high-protein snacks are potential convenient sources of high-quality protein and serve as a healthier alternative for patients with type 2 diabetes, who may have limited snack product choices. Such snacks may also provide balanced nutrition to pre-diabetic and obese individuals.

Prolonged bisphenol-A exposure decreases endocrine pancreatic proliferation in response to obesogenic diet in ovariectomized mice

Research on the deleterious actions of bisphenol (BP)-A have focused on its effects on insulin secretion during pre/perinatal periods or adulthood. Estrogens also modulate endocrine pancreas physiology in females during aging; however, the effects of BPA on islet morphophysiology after menopause have not been investigated. We evaluated the effects of BPA exposure on glucose homeostasis and islet morphofunction in ovariectomized (OVX) mice fed on a high-fat diet (HFD). Adult Swiss female mice were underwent to bilateral ovariectomy, and with the confirmation of the establishment of surgical menopause, the females were then submitted, or not,to a normolipidic diet or HFD [control (CTL) and HFD groups, respectively] without or with 1 μg/mL BPA in their drinking water (CBPA and HBPA groups) for 90 days. HFD females displayed obesity, hyperglycemia, hyperinsulinemia, glucose intolerance and insulin resistance. BPA did not modulate HFD-induced obesity or body glucose impairments in HBPA females, and islets isolated from both the HFD and HBPA groups exhibited insulin hypersecretion. The HBPA islets, however, displayed enlarged islet cells and reduced proliferation, in association with the downregulation of mRNAs encoding PDX-1, NGN3 and CCND2 and upregulation of mRNAs encoding ER-β, GPR30, TNF-α and IL-1β in HBPA islets. BPA consumption in OVX mice impaired the islet-cell hyperplasia response to the HFD, partly mediated by increased expression of ER-β and GPR30, which impaired the expression of major genes involved in islet-cell survival and functionality. Together with higher pro-inflammatory cytokines expression in the islet milieu, these alterations may accelerate β-cell failure in postmenopause.

Follicle stimulating hormone, its association with glucose and lipid metabolism during the menopausal transition

AIM

Accumulative evidence shows that follicle stimulating hormone (FSH) is associated with metabolic disorders. We aimed to ascertain the relationship between FSH, blood glucose and lipid metabolism in general perimenopausal women.

METHODS

This cross-sectional study analyzed 2121 perimenopausal women aged 40-54 years in Zhejiang Province from January 2016 to December 2018. Regression analysis was performed to assess the relationship between FSH and metabolic parameters.

RESULTS

Serum FSH had a significant inverse association with fasting plasma glucose (P < 0.05) and triglycerides (TG) (P < 0.01) in perimenopausal women. However, after adjusting for body mass index, there was no significant association between FSH and fasting plasma glucose. In a model fully adjusted for demographic variables, estradiol, body mass index, high-density lipoprotein, low-density lipoprotein, homocysteine, systolic blood pressure and blood viscosity, a significant association still existed between FSH and TG (standardized β = -0.095; R² = 0.155; P = 0.002).

CONCLUSION

Overall, FSH is negatively associated with metabolic parameters, especially TG, in perimenopausal women. These results indicated that FSH might be a biomarker for the primary prevention of disorders with lipid metabolism during the menopausal period.

Sexual dimorphism of gut microbiota at different pubertal status

Background

Accumulating evidence infer that gut microbiome-host relations are key mediators or modulators driving the observed sexual dimorphism in some disease onset and progression. To date, the sex-differences of gut microbiota at different pubertal status have not been reported.

Objective

To determine the characteristics of gut microbiota of both genders at different pubertal status.

Methods

Gut microbiota was analyzed in 89 Chinese participants aged 5–15 years. Participants were divided into pre-puberty and puberty groups for both male and female. The composition of gut microbiota was investigated by 16S rRNA-based metagenomics. Ecological representations of microbial communities were computed. The prediction of metagenomic functional content from 16S rRNA gene surveys was conducted.

Results

There were 49 males (9.76 ± 2.15 years) and 40 females (9.74 ± 1.63 years); 21 males and 26 females were at puberty. At genus level, Alistipes, Megamonas, Oscillospira and Parabacteroides were more prevalent in girls than in boys (p < 0.05). There were no significantly differences of alpha-diversity between genders, which was independent of pubertal status. The beta-diversity was significantly different in pubertal subjects between genders. Using statistical analyses, we assigned genera Dorea, Megamonas, Bilophila, Parabacteroides and Phascolarctobacterium as microbial markers for pubertal subjects. The predicted metabolic profiles differ in both pubertal and pre-pubertal groups between genders.

Conclusion

This cross-sectional study revealed that sex differences in the gut microbiota composition and predicted metabolic profiles exist before puberty, which become more significant at puberty. The identification of novel puberty bacterial markers may disclose a potential effects of gender-related microbiota profiles on puberty onset.

Roles of follicle stimulating hormone and its receptor in human metabolic diseases and cancer

Follicle stimulating hormone (FSH) and its receptor (FSHR) play an important role in human metabolic diseases and cancer. Evidence showed that FSHR is not only distributed in ovary and testis but also in other cells or organs such as osteoclast, adipocytes, liver, pituitary cancer and so forth. Moreover, FSH is associated with lipogenesis, inflammation, insulin sensitivity, thermogenesis, skeletal metabolism, osteogenesis and ovarian cancer, all of which have been confirmed closely related to metabolic diseases or metabolic-related cancer. Therefore, FSH and FSHR may be potential therapeutic targets for metabolic diseases and metabolic-related cancer. Epidemiological researches revealed close relationship between FSH/FSHR and metabolic diseases or cancer. Experimental studies elucidated the underlying mechanism both in vivo and in vitro. We reviewed the recent researches and present an integrated framework of FSH/FSHR and metabolic diseases and cancer, which provides potential targets for the treatments of metabolic diseases and cancer.

Association between reproductive years and insulin resistance in middle-aged and older women: A 10-year prospective cohort study

OBJECTIVES

We hypothesized that reproductive years, a marker of total estrogen exposure, may play an important role in insulin resistance.

STUDY DESIGN

A total of 3327 middle-aged and older women (age range 40-69 years) from the Korean Genome and Epidemiology Study were included in this large prospective cohort study with a mean follow-up of 10.8 years.

MAIN OUTCOME MEASURES

Insulin resistance and sensitivity were calculated using the homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI). A linear mixed model for a repeated-measures covariance pattern with unstructured covariance within participants was used to assess longitudinal associations between baseline reproductive years and subsequent changes in HOMA-IR and QUICKI. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for new-onset insulin resistance according to quartiles of reproductive years.

RESULTS

Changes in HOMA-IR were significantly greater in Q1 (fewest reproductive years) than in Q4 (most reproductive years) (beta[SE] = 0.038[0.016]; p-value = 0.022), while changes in QUICKI were significantly smaller in Q1 than in Q4 (beta[SE] = -0.001[0.000]; p-value = 0.048) after adjusting for possible confounders over time. Compared with Q1, HRs (95 % CIs) for the incidence of new-onset insulin resistance were 0.807 (0.654-0.994) for Q2, 0.793 (0.645-0.974) for Q3, and 0.770 (0.622-0.953) for Q4 after adjusting for possible confounders.

CONCLUSION

A short reproductive period is associated with elevated levels on the HOMA-IR and decreased levels on the QUICKI over time. The lowest quartile of reproductive years was significantly associated with a higher risk of new-onset insulin resistance.

Follicle stimulating hormone and estradiol trajectories from menopausal transition to late postmenopause in indigenous Chinese women

OBJECTIVE

The aim of this study was to examine follicle stimulating hormone (FSH) and estradiol (E2) trajectories in indigenous Chinese women through the ovarian aging process from 10 years before the final menstrual period (FMP) to 20 years after.

METHODS

A prospective community-based longitudinal cohort study of 362 Chinese middle-aged women with a clearly determined FMP was performed.

RESULTS

FSH and E2 trajectories were identified according to years from FMP and the Stages of Reproductive Aging Workshop + 10 (STRAW + 10), and further classified by body mass index. E2 decreases relatively steadily from Stage -2 to +1c, while FSH stabilizes quickly from Stage -2 to +1a. Obese women have higher E2 levels and lower FSH levels during menopausal transition, which last for decades after the FMP. There was no obvious decline in FSH levels for at least 20 years after the FMP.

CONCLUSIONS

The FSH and E2 trajectories in this indigenous Chinese cohort appear similar to those discussed in the Study of Women's Health Across the Nation, with ethnic differences. STRAW + 10 criteria may be used to ascertain the ovarian aging process in Chinese women. Obese women may experience different levels of hormonal fluctuations during the menopause transition, while FSH levels in all women appear to remain high even at late postmenopause.

Diabetes in Menopause: Risks and Management

The aim of this review is to present, critically appraise and qualitatively synthesize current evidence on the risk of type 2 diabetes mellitus (T2DM) development during menopause, the management of climacteric symptoms in women with T2DM and the management of T2DM in postmenopausal women. Menopause represents the end of reproductive life in women, as a result of ovarian aging. It is characterized by substantial decrease in the endogenous oestrogen concentrations and it is accompanied by alterations in body weight, adipose tissue distribution and energy expenditure, as well as insulin secretion, insulin sensitivity and activity that can predispose to the development of T2DM, independently of, and additively to, aging. Many women in midlife experience climacteric symptoms, including hot flushes and night sweats, resulting in an indication to receive Hormone Replacement Treatment (HRT). HRT has a favourable effect on glucose homeostasis both in women without and with T2DM. The latter was considered in the past as a cardiovascular disease (CVD) equivalent, which would suggest that women with the disease should not receive HRT. However, nowadays evidence exists to support an individualized approach of women based on their CVD risk, as some women with T2DM may be excellent candidates for HRT. Regarding T2DM management for women in menopause, lifestyle intervention, including diet and exercise, constitutes its cornerstone. However, most of these women will eventually require pharmacologic therapy. The most suitable agents should be selected according to their metabolic, cardiovascular and bone effects, taking into consideration the specific characteristics and comorbidities of each postmenopausal woman.

Cardiovascular Risk in Perimenopausal Women

Cardiovascular disease, and particularly coronary heart disease (CHD), has a low incidence in premenopausal women. Loss of ovarian hormones during the perimenopause and menopause leads to a sharp increase in incidence. Although most CHD risk factors are common to both men and women, the menopause is a unique additional risk factor for women. Sex steroids have profound effects on many CHD risk factors. Their loss leads to adverse changes in lipids and lipoproteins, with increases being seen in low density lipoprotein (LDL) cholesterol and triglycerides, and decreases in high density lipoprotein (HDL) cholesterol. There is a reduction in insulin secretion and elimination, but increases in insulin resistance eventually result in increasing circulating insulin levels. There are changes in body fat distribution with accumulation in central and visceral fat which links to the other adverse metabolic changes. There is an increase in the incidence of hypertension and of type 2 diabetes mellitus, both major risk factors for CHD. Oestrogens have potent effects on blood vessels and their loss leads to dysfunction of the vascular endothelium. All of these changes result from loss of ovarian function contributing to the increased development of CHD. Risk factor assessment in perimenopausal women is recommended, thereby permitting the timely introduction of lifestyle, hormonal and therapeutic interventions to modify or reverse these adverse changes.

Aging Reduces Estradiol Protection Against Neural but Not Metabolic Effects of Obesity in Female 3xTg-AD Mice

Vulnerability to Alzheimer's disease (AD) is increased by several risk factors, including midlife obesity, female sex, and the depletion of estrogens in women as a consequence of menopause. Conversely, estrogen-based hormone therapies have been linked with protection from age-related increases in adiposity and dementia risk, although treatment efficacy appears to be affected by the age of initiation. Potential interactions between obesity, AD, aging, and estrogen treatment are likely to have significant impact on optimizing the use of hormone therapies in postmenopausal women. In the current study, we compared how treatment with the primary estrogen, 17β-estradiol (E2), affects levels of AD-like neuropathology, behavioral impairment, and other neural and systemic effects of preexisting diet-induced obesity in female 3xTg-AD mice. Importantly, experiments were conducted at chronological ages associated with both the early and late stages of reproductive senescence. We observed that E2 treatment was generally associated with significantly improved metabolic outcomes, including reductions in body weight, adiposity, and leptin, across both age groups. Conversely, neural benefits of E2 in obese mice, including decreased β-amyloid burden, improved behavioral performance, and reduced microglial activation, were observed only in the early aging group. These results are consistent with the perspective that neural benefits of estrogen-based therapies require initiation of treatment during early rather than later phases of reproductive aging. Further, the discordance between E2 protection against systemic versus neural effects of obesity across age groups suggests that pathways other than general metabolic function, perhaps including reduced microglial activation, contribute to the mechanism(s) of the observed E2 actions. These findings reinforce the potential systemic and neural benefits of estrogen therapies against obesity, while also highlighting the critical role of aging as a mediator of estrogens' protective actions.

Type 2 Diabetes Mellitus and Menopausal Hormone Therapy: An Update

During menopausal transition, various phenotypical and metabolic changes occur, affecting body weight, adipose tissue distribution and energy expenditure as well as insulin secretion and sensitivity. Taken together, these can predispose women to the development of type 2 diabetes mellitus (T2DM). Many women in midlife experience climacteric symptoms, including hot flashes and night sweats. Menopausal hormone therapy (MHT) is then indicated. MHT has a favourable effect on glucose homeostasis in both women without and with T2DM. T2DM was considered in the past as a cardiovascular disease (CVD) equivalent, which would suggest that women with T2DM should not receive MHT. This notion may still deter many clinicians from prescribing MHT to these patients. However, nowadays there is strong evidence to support an individualised approach after careful evaluation of CVD risk. In older women with T2DM (> 60 years old or > 10 years in menopause), MHT should not be initiated, because it may destabilise mature atherosclerotic plaques, resulting in thrombotic episodes. In obese women with T2DM or in women with moderate CVD risk, transdermal 17β-oestradiol could be used. This route of delivery presents beneficial effects regarding triglyceride concentrations and coagulation factors. In peri- or recently post-menopausal diabetic women with low risk for CVD, oral oestrogens can be used, since they exhibit stronger beneficial effects on glucose and lipid profiles. In any case, a progestogen with neutral effects on glucose metabolism should be used, such as natural progesterone, dydrogesterone or transdermal norethisterone. The goal is to maximise benefits and minimise adverse effects.

Sex and Gender Driven Modifiers of Alzheimer's: The Role for Estrogenic Control Across Age, Race, Medical, and Lifestyle Risks

Research indicates that after advanced age, the major risk factor for late-onset Alzheimer’s disease (AD) is female sex. Out of every three AD patients, two are females with postmenopausal women contributing to over 60% of all those affected. Sex- and gender-related differences in AD have been widely researched and several emerging lines of evidence point to different vulnerabilities that contribute to dementia risk. Among those being considered, it is becoming widely accepted that gonadal steroids contribute to the gender disparity in AD, as evidenced by the “estrogen hypothesis.” This posits that sex hormones, 17β-estradiol in particular, exert a neuroprotective effect by shielding females’ brains from disease development. This theory is further supported by recent findings that the onset of menopause is associated with the emergence of AD-related brain changes in women in contrast to men of the same age. In this review, we discuss genetic, medical, societal, and lifestyle risk factors known to increase AD risk differently between the genders, with a focus on the role of hormonal changes, particularly declines in 17β-estradiol during the menopause transition (MT) as key underlying mechanisms.

Gonadotropins and Their Association with the Risk of Prediabetes and Type 2 Diabetes in Middle-Aged Postmenopausal Women

Recent studies have suggested that a low concentration of follicle-stimulating hormone (FSH) is associated with a higher prevalence of metabolic disturbances in postmenopausal women. In this study, we aim to evaluate the association between FSH, luteinizing hormone (LH), and LH/FSH ratio values and the risk of insulin resistance (HOMA-IR >2.0), prediabetes (IFG), and type 2 diabetes in a 5-year prospective study in postmenopausal women. 114 postmenopausal women were divided into 4 groups: group 1 (baseline and follow-up normoglycemic women), group 2 (normoglycemic women at baseline progressing to IFG), group 3 (women with baseline and follow-up IFG), and group 4 (women with baseline IFG progressing to diabetes). Baseline and follow-up anthropometric measurements and blood collections were performed. Serum/plasma was assayed for glucose, HDL-C, TG, C-reactive protein (CRP), 17beta-estradiol, estrone, insulin, thyroid-stimulating hormone (TSH), FSH, and LH. Homeostatic model assessment of insulin resistance (HOMA-IR) and LH/FSH ratios were calculated. The baseline concentrations of FSH and LH statistically decreased across all four groups (the highest concentrations in group 1 and the lowest in group 4; p < 0.001). A logistic regression analysis showed that a 1 SD decrease in the z-score of FSH concentration is associated with a threefold increased risk of IFG and a fivefold increased risk of HOMA-IR of >2.0 and diabetes. The LH concentration had odds ratio (OR) values about two times lower than the FSH concentration. The ORs of the LH/FSH ratio were only significant for IFG. In conclusion, FSH concentration is strongly associated with insulin resistance, prediabetes, and diabetes in postmenopausal women with normal or impaired fasting glucose. LH and the LH/FSH ratio are also related to metabolic disturbances after menopause, yet to a lesser extent.

Investigation of Comorbidity, Trauma History, and Osteoporotic Fractures in the Postmenopausal Population: A Nationwide, Observational, and Cross-Sectional Study of Korean Orthopedic Outpatient Clinics

Study Design

A nationwide, observational, and cross-sectional study targeting postmenopausal patients from 62 orthopedic outpatient clinics in Korea between October 2010 and February 2011.

Purpose

This study was carried out to investigate comorbidity, trauma history, and the status of osteoporotic fracture treatment in Korean postmenopausal women.

Overview of Literature

There has been little reports on the comorbidity, family history, trauma history, and treatment status of osteoporotic fractures in patients visiting the orthopedic outpatient clinics in Korea.

Methods

A total of 1,255 postmenopausal women between the ages of 50 and 80 years were enrolled in the study and the population distribution was reflected by region. Comorbidity, familial history of osteoporosis, familial history of osteoporotic fracture, history of falls, and status of osteoporotic fracture management were evaluated using an interview and questionnaire. The relationship between family history of osteoporosis and bone mineral density was analyzed.

Results

A number of patients (23%) had a family history of osteoporosis and 16.5% had a family history of fractures. Most (64.7%) of the patients had one or more comorbidities, including 58.8% exhibiting a chronic disease and 16.4% suffering from diseases that restrict exercise or walking. The results of the questionnaire indicated that 21.8% of these fracture patients had experienced a fracture previously and that the most common type of fracture was that of the spine. Lumbar spine bone mineral density was found to be lower in the presence of family history of osteoporosis.

Conclusions

Postmenopausal women are liable to have osteoporotic fractures due to the high prevalence of osteoporosis, a history of falling, and the comorbidity with diseases that restrict ambulation. A better understanding of postmenopausal women in the orthopedic outpatient settings is important to the management of osteoporotic fractures.

Cardiovascular Implications of the Menopause Transition: Endogenous Sex Hormones and Vasomotor Symptoms

The menopause transition (MT) is a critical period of women's lives marked by several physiologic changes and menopause-related symptoms that have implications for health. Risk for cardiovascular disease, the leading cause of death in women, increases after menopause, suggesting a contribution of the MT to its development. This article focuses on the relationship between 2 main features of the MT and women's cardiovascular health: (1) dynamic alterations of sex hormones, particularly endogenous estradiol and follicle-stimulating hormone, and (2) vasomotor symptoms, the cardinal symptom of the menopause. Limitations and future directions are discussed.

Menopause and diabetes: EMAS clinical guide

INTRODUCTION

Whether menopause increases the risk of type 2 diabetes mellitus (T2DM) independently of ageing has been a matter of debate. Controversy also exists about the benefits and risks of menopausal hormone therapy (MHT) in women with T2DM.

AIMS

To summarise the evidence on 1) the effect of menopause on metabolic parameters and the risk of T2DM, 2) the effect of T2DM on age at menopause, 3) the effect of MHT on the risk of T2DM, and 4) the management of postmenopausal women with T2DM.

MATERIALS AND METHODS

Literature review and consensus of experts' opinions.

RESULTS AND CONCLUSION

Metabolic changes during the menopausal transition include an increase in and the central redistribution of adipose tissue, as well as a decrease in energy expenditure. In addition, there is impairment of insulin secretion and insulin sensitivity and an increase in the risk of T2DM. MHT has a favourable effect on glucose metabolism, both in women with and in women without T2DM, while it may delay the onset of T2DM. MHT in women with T2DM should be administered according to their risk of cardiovascular disease (CVD). In women with T2DM and low CVD risk, oral oestrogens may be preferred, while transdermal 17β-oestradiol is preferred for women with T2DM and coexistent CVD risk factors, such as obesity. In any case, a progestogen with neutral effects on glucose metabolism should be used, such as progesterone, dydrogesterone or transdermal norethisterone. Postmenopausal women with T2DM should be managed primarily with lifestyle intervention, including diet and exercise. Most of them will eventually require pharmacological therapy. The selection of antidiabetic medications should be based on the patient's specific characteristics and comorbidities, as well on the metabolic, cardiovascular and bone effects of the medications.

Serum follicle stimulating hormone is associated with reduced risk of diabetes in postmenopausal women: The Hong Kong osteoporosis study

Menopause is an important transition of reproductive stage in a woman's life. It is associated with diabetes, but the role of follicle stimulating hormone (FSH), a menopause-related hormone, in the risk of diabetes is largely unknown. We evaluated the relationship between serum FSH and diabetes in 1274 participants from the Hong Kong Osteoporosis Study aged≥55 at baseline. We also searched relevant databases for studies on serum FSH and incident diabetes and conducted a meta-analysis using fixed-effect modeling. Cases of incident diabetes (N = 60) were ascertained during a median follow-up of 10.7 years. Serum FSH was significantly associated with reduced risk of diabetes in both a crude model (hazard ratio [HR] per SD increase: 0.66; 95% CI: 0.48-0.89; P = 0.007) and a full model with adjustment for age, sex, body mass index, factors related to risk of diabetes, and reproductive health (HR per SD increase: 0.70; 95% CI: 0.51-0.97; P = 0.030); a similar result was observed when FSH was analysed in quintiles. In a fixed-effect meta-analysis of two studies, including the current study, serum FSH > 50 IU/L was associated with reduced risk of diabetes (HR = 0.56; 95% CI: 0.36-0.85; P = 0.006; I² = 0). In conclusion, serum FSH levels were independently associated with diabetes.

Menopausal Hormone Therapy and Type 2 Diabetes Prevention: Evidence, Mechanisms, and Clinical Implications

Type 2 diabetes has reached epidemic proportions in the United States. Large, randomized controlled trials suggest that menopausal hormone therapy (MHT) delays the onset of type 2 diabetes in women. However, the mechanisms and clinical implications of this association are still a matter of controversy. This review provides an up-to-date analysis and integration of epidemiological, clinical, and basic studies, and proposes a mechanistic explanation for the effect of menopause and MHT on type 2 diabetes development and prevention. We discuss the beneficial effects of endogenous estradiol with respect to insulin secretion, insulin sensitivity, and glucose effectiveness; we also discuss energy expenditure and adipose distribution, both of which are affected by menopause and improved by MHT, which thereby decreases the incidence of type 2 diabetes. We reconcile differences among studies that investigated the effect of menopause and MHT formulations on type 2 diabetes. We argue that discrepancies arise from physiological differences in methods used to assess glucose homeostasis, ranging from clinical indices of insulin sensitivity to steady-state methods to assess insulin action. We also discuss the influence of the route of estrogen administration and the addition of progestogens. We conclude that, although MHT is neither approved nor appropriate for the prevention of type 2 diabetes due to its complex balance of risks and benefits, it should not be withheld from women with increased risk of type 2 diabetes who seek treatment for menopausal symptoms.