Increased visceral fat and decreased energy expenditure during the menopausal transition

Sex differences in white adipose tissue expansion: emerging molecular mechanisms

The escalating prevalence of individuals becoming overweight and obese is a rapidly rising global health problem, placing an enormous burden on health and economic systems worldwide. Whilst obesity has well described lifestyle drivers, there is also a significant and poorly understood component that is regulated by genetics. Furthermore, there is clear evidence for sexual dimorphism in obesity, where overall risk, degree, subtype and potential complications arising from obesity all differ between males and females. The molecular mechanisms that dictate these sex differences remain mostly uncharacterised. Many studies have demonstrated that this dimorphism is unable to be solely explained by changes in hormones and their nuclear receptors alone, and instead manifests from coordinated and highly regulated gene networks, both during development and throughout life. As we acquire more knowledge in this area from approaches such as large-scale genomic association studies, the more we appreciate the true complexity and heterogeneity of obesity. Nevertheless, over the past two decades, researchers have made enormous progress in this field, and some consistent and robust mechanisms continue to be established. In this review, we will discuss some of the proposed mechanisms underlying sexual dimorphism in obesity, and discuss some of the key regulators that influence this phenomenon.

Exploring Obesity as a Gendered Contagion: Impact on Lifestyle Interventions to Improve Cardiovascular Health

PURPOSE

Obesity increases the risk of cardiovascular disease. Lifestyle interventions such as physical activity and diet are important components for reducing the risk of obesity. Data suggest that lifestyle choices differ between men and women, as well as in groups. The purpose of this review was to explore whether obesity can be considered as a gendered social contagion, associated with differences in lifestyle and response to lifestyle interventions in men and women.

FINDINGS

There are important sex-based differences of obesity to consider. There is evidence that peers have an influence on lifestyle preferences such as physical activity level and dietary habits, but the evidence is inconclusive if the differences exist between men and women. Similarly, data from lifestyle intervention studies are not conclusive whether there are differences between men and women. There is not enough evidence for the notion that obesity is a gendered social contagion.

IMPLICATIONS

More research is needed to understand differences in lifestyle and lifestyle interventions between men and women, especially across the life span, which could have profound public health implications.

Heterogeneity of non-alcoholic fatty liver disease: Implications for clinical practice and research activity

Non-alcoholic fatty liver disease (NAFLD) is a heterogeneous condition with a wide spectrum of clinical presentations and natural history and disease severity. There is also substantial inter-individual variation and variable response to a different therapy. This heterogeneity of NAFLD is in turn influenced by various factors primarily demographic/dietary factors, metabolic status, gut microbiome, genetic predisposition together with epigenetic factors. The differential impact of these factors over a variable period of time influences the clinical phenotype and natural history. Failure to address heterogeneity partly explains the sub-optimal response to current and emerging therapies for fatty liver disease. Consequently, leading experts across the globe have recently suggested a change in nomenclature of NAFLD to metabolic-associated fatty liver disease (MAFLD) which can better reflect current knowledge of heterogeneity and does not exclude concomitant factors for fatty liver disease (e.g. alcohol, viral hepatitis, etc.). Precise identification of disease phenotypes is likely to facilitate clinical trial recruitment and expedite translational research for the development of novel and effective therapies for NAFLD/MAFLD.

Are sex disparities in COVID-19 a predictable outcome of failing men's health provision?

The COVID-19 pandemic, caused by the SARS-CoV-2 coronavirus, has taken a catastrophic toll on society, health-care systems and the economy. Notably, COVID-19 has been shown to be associated with a higher mortality rate in men than in women. This disparity is likely to be a consequence of a failure to invest in men’s health, as it has also been established that men have a lower life expectancy and poorer outcomes from non-communicable diseases than women. A variety of biological, social and economic factors have contributed to the sex disparities in mortality from COVID-19. A streamlined men’s health programme — with the urologist as the gatekeeper of men’s health — is needed to help prevent future tragedies of this nature.

COVID-19 has been shown to be associated with a higher mortality rate in men than in women. In this Perspectives article, the authors posit that this disparity is due to a failure to invest in men’s health and discuss the biological, social and economic factors that have contributed to the sex disparities in mortality from COVID-19, as well as considering how a streamlined men’s health programme with the urologist in a central role could address these issues.

Postmenopausal Chinese-Singaporean Women Have a Higher Ratio of Visceral to Subcutaneous Adipose Tissue Volume than Caucasian Women of the Same Age and BMI

Central fat accumulation is a significant determinant of cardio-metabolic health risk, known to differ between ethnically distinct human populations. Despite evidence for preferential central adiposity in Asian populations, the proportional distribution between the subcutaneous and visceral compartments in Chinese postmenopausal women has not been thoroughly investigated. For this analysis, volumetrically quantified subcutaneous and visceral adipose tissue (SAT, VAT) in the pelvic and abdominal regions of postmenopausal Asian (Chinese-Singaporean) and Caucasian (German) women matched for age and Body Mass Index (BMI) was undertaken, to examine such differences between the two groups. Volumes were calculated from segmentations of magnetic resonance imaging datasets of the abdomen and pelvis. Despite SAT, VAT, and the corresponding total adipose tissue (TAT) being similar between the groups, VAT/SAT and VAT/TAT were higher in the Asian group (by 24.5% and 18.2%, respectively, each p = 0.02). Further, VAT/SAT and VAT/TAT were positively correlated with BMI in the Caucasian group only (p = 0.02 and p = 0.01, respectively). We concluded that VAT is proportionally higher in the non-obese Asian women, compared to the Caucasian women of matched age and BMI. This conclusion is in agreement with existing literature showing higher abdominal adiposity in Asian populations. Additionally, in the Asian group, BMI did not correlate with visceral adiposity on a significant level. Further analysis is required to examine the extent to which this increased VAT may impact cardio-metabolic health. There is, however, a need to emphasize healthy lifestyle behaviors in non-obese post-menopausal women of Chinese ancestry.

Association between Equol Production Status and Nonalcoholic Steatohepatitis

Equol is a metabolite of daidzein, a major soybean isoflavone with estrogenic and antioxidant activities. As the production of equol depends on the presence of certain members of the intestinal microflora, not all individuals can produce equol. We examined the relationship between NASH histological features and equol production. In an animal model, obese OLETF rats were intraperitoneally injected with a porcine serum to augment liver fibrogenesis. Equol-rich soy product, SE5-OH was orally administered during the experimental period. Treatment with SE5-OH markedly attenuated the development of liver fibrosis and expression of alpha-smooth muscle actin. In clinical research, 38 NAFLD patients (13 men and 25 women) were included. The degree of fibrosis and ballooning in equol-nonproducers was significantly higher than in equol-producers in women. The percentage of nonproducers with NAFLD activity score (NAS) ≥ 5 was significantly higher than that of producers. None of the histological features were significantly different between nonproducers and producers in men. Decision tree analysis identified predictors for NAS ≥ 5 in women. The status of equol production was the strongest predictor, followed by fasting glucose. Since equol can be noninvasively detected in urine, it can be applied as a screening tool for the progression of NASH in women.

Changes in body weight and metabolic risk during time restricted feeding in premenopausal versus postmenopausal women

BACKGROUND

Time restricted feeding (TRF) involves confining the eating window to a specific number of hours, and fasting for the remaining hours of the day.

OBJECTIVE

This study examined if changes in body weight and metabolic risk factors during TRF, differ between premenopausal and postmenopausal women.

METHODS

This is a secondary analysis of an 8-week TRF study (4-6 h eating window, 18-20 h fasting window daily) conducted in adults with obesity. Male participants were excluded, and female subjects were classified in two groups based on menstrual status: premenopausal (n = 13), or postmenopausal (n = 19). Perimenopausal women were excluded from the original study.

RESULTS

Body weight decreased by week 8 in premenopausal women (-3.3 ± 0.4%) and postmenopausal women (-3.3 ± 0.5%) (main effect of time, P < 0.001), with no difference between groups (no group × time interaction). Adherence was excellent in both groups, with premenopausal women adhering to their prescribed eating window on 6.2 ± 0.1 d/week, and postmenopausal women adhering to their window on 6.2 ± 0.2 d/week. Fat mass, lean mass, fasting insulin, insulin resistance, and 8-isoprostane (marker of oxidative stress) were reduced similarly in both groups (main effect of time, P < 0.05 for all comparisons). Visceral fat mass, relative skeletal muscle index (RSMI), blood pressure, LDL cholesterol, HDL cholesterol, triglycerides, fasting glucose, HbA1c, TNF-alpha and IL-6 remained unchanged in both groups by week 8.

CONCLUSION

These findings suggest that the weight loss and metabolic benefits of TRF do not differ between premenopausal and postmenopausal women with obesity.

Early decrease in lean mass and bone mass in postmenopausal women: a cross-sectional study

OBJECTIVE

The effect of menopause transition in body composition was evaluated in a cross-sectional study.

METHOD

The study was carried out in an outpatient clinic of Brazil enrolling premenopausal (n = 64) and postmenopausal (n = 42) women aged between 44 and 52 years, with weight stability (±2 kg) for at least 6 months before evaluation. Participants answered a sociodemographic semi-structured questionnaire, the Menopause Rating Scale, the International Physical Activity Questionnaire, 24-h dietary recall and a visual analogue scale of appetite. Blood biochemical, anthropometry and densitometry measurements were used for body composition estimation.

RESULTS

Most participants were overweight (31.4%) or obese (45.7%) and categorized as 'high active' in physical activity (65.7%). Lean mass and bone mass decreased in the first few years of menopause. A metabolic turn to an increase of lipids was observed, represented by greater total cholesterol and high-density lipoprotein cholesterol levels. Menopause transition did not alter body fat distribution. Total body fat, android fat and gynoid fat were positively related to smoking habit, and android fat was also positively related to waist circumference.

CONCLUSION

Taken together, early postmenopause can be considered a time window of opportunity for preventing ailments such as atherogenic profile, obesity, increased cardiovascular risk and osteoporosis.

Anthropometric Indices and Age at Natural Menopause: A 15-Year Follow-up Population-Based Study

BACKGROUND

Following menopause, the risk of many diseases is increased, and this situation may be due to changes in anthropometric indices (AI), while the association between adiposity and age at natural menopause (ANM) is not clear yet.

OBJECTIVES

This longitudinal study was conducted to investigate the ability of AI in predicting ANM.

METHODS

For this purpose, a total of 3,876 women aged > 20 years old from participants of the Tehran lipid and glucose study (TLGS) met our eligibility criteria. The association between ANM and various AIs was assessed using the Accelerated Failure Time (AFT) model, and time ratio (TR) with 95% confidence intervals was reported in this longitudinal study.

RESULTS

The median [interquartile range (IQR) 25 - 75] of the survival time was 12.5 (7.9 - 15.8) years. At the end of the follow-up, 1,479 (38.2%) of the participants reached menopause. The median time to natural menopause was decreased by about 2% with one standard deviation (SD) increase of both a body shape index (ABSI) (time ratio (TR): 0.98, 95% CI: 0.97, 0.99) and lipid accumulation product (LAP) (TR: 0.98, 95% CI: 0.98, 0.99) z-scores; and this time was increased by about 1% (TR: 1.01, 95% CI: 1.00, 1.02) with one SD increase in body mass index (BMI) z-score.

CONCLUSIONS

The ABSI, LAP, and BMI were the most useful AIs for identification of the time to menopause onset, and ABSI and LAP were inversely associated with the ANM. Also, the BMI was directly associated with the ANM.

FSH Level and Changes in Bone Mass and Body Composition in Older Women and Men

CONTEXT

FSH may have independent actions on bone remodeling and body fat regulation. Cross-sectionally, we have shown that serum FSH is associated with bone mineral density (BMD) and body fat in older postmenopausal women, but it remains unknown whether FSH predicts bone and fat changes.

OBJECTIVE

We examined whether baseline FSH level is associated with subsequent bone loss or body composition changes in older adults.

SETTING, DESIGN, PARTICIPANTS

We studied 162 women and 158 men (mean age 82 ± 4 years) from the Age, Gene/Environment Susceptibility (AGES)-Bone Marrow Adiposity cohort, a substudy of the AGES-Reykjavik Study of community-dwelling older adults. Skeletal health and body composition were characterized at baseline and 3 years later.

MAIN OUTCOMES

Annualized change in BMD and body composition by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). Models were adjusted for serum estradiol and testosterone levels.

RESULTS

There was no evidence for an association between baseline FSH level and change in BMD or body composition by DXA or QCT. For femoral neck areal BMD, adjusted mean difference (95% CI) per SD increase in FSH was 1.3 (-0.7 to 3.3) mg/cm2/y in women, and -0.2 (-2.6 to 2.2) mg/cm2/y in men. For visceral fat, adjusted mean difference (95% CI) per SD increase in FSH was 1.80 (-0.03 to 3.62) cm2/y in women, and -0.33 (-3.73 to 3.06) cm2/y in men.

CONCLUSIONS

Although cross-sectional studies and studies in perimenopausal women have demonstrated associations between FSH and BMD and body composition, in older adults, FSH level is not associated with bone mass or body composition changes.

Dietary Intake and Energy Expenditure in Breast Cancer Survivors: A Review

Many breast cancer survivors (BCS) gain fat mass and lose fat-free mass during treatment (chemotherapy, radiation, surgery) and estrogen suppression therapy, which increases the risk of developing comorbidities. Whether these body composition alterations are a result of changes in dietary intake, energy expenditure, or both is unclear. Thus, we reviewed studies that have measured components of energy balance in BCS who have completed treatment. Longitudinal studies suggest that BCS reduce self-reported energy intake and increase fruit and vegetable consumption. Although some evidence suggests that resting metabolic rate is higher in BCS than in age-matched controls, no study has measured total daily energy expenditure (TDEE) in this population. Whether physical activity levels are altered in BCS is unclear, but evidence suggests that light-intensity physical activity is lower in BCS compared to age-matched controls. We also discuss the mechanisms through which estrogen suppression may impact energy balance and develop a theoretical framework of dietary intake and TDEE interactions in BCS. Preclinical and human experimental studies indicate that estrogen suppression likely elicits increased energy intake and decreased TDEE, although this has not been systematically investigated in BCS specifically. Estrogen suppression may modulate energy balance via alterations in appetite, fat-free mass, resting metabolic rate, and physical activity. There are several potential areas for future mechanistic energetic research in BCS (e.g., characterizing predictors of intervention response, appetite, dynamic changes in energy balance, and differences in cancer sub-types) that would ultimately support the development of more targeted and personalized behavioral interventions.

Efficacy of black rice extract on obesity in obese postmenopausal women: a 12-week randomized, double-blind, placebo-controlled preliminary clinical trial

OBJECTIVES

Postmenopausal obesity is a paramount health concern among older women. Black rice is a well-known pigmented rice variety with a higher anthocyanin content. Both in vitro and in vivo studies have demonstrated the effects of black rice on obesity. The present study aimed to investigate the effects of black rice extract (BRE) on obesity among obese postmenopausal women from Korea.

METHODS

This was a 12-week, randomized, double-blind, placebo-controlled preliminary clinical trial. The participants were postmenopausal women who had stopped menstruating for more than a year. Specifically, 105 participants were randomly assigned to the BRE (1 g/d) or placebo (maltodextrin, 1 g/d) group.

RESULTS

Eighty-eight participants completed the study, 47 in the intervention group and 41 in the placebo group. At the study endpoint, dual-energy x-ray absorptiometry assessment showed that the BRE group had a significantly lower trunk fat (P = 0.04), total fat (P = 0.04), and total body fat percentage (P = 0.04) than did the placebo group. The body fat percentage (P = 0.04) was lower in the BRE group with marginal significance, and there were no significant differences in anthropometric measures such as weight, body mass index, waist circumference, or waist-to-hip ratio estimated by bioelectrical impedance analysis.

CONCLUSION

BRE supplementation for 12 weeks seems to be effective in reducing fat accumulation in postmenopausal women.

Changes in Regional Fat Distribution and Anthropometric Measures Across the Menopause Transition

CONTEXT

The relation between the menopause transition (MT) and changes in regional fat distribution is uncertain.

OBJECTIVE

To determine whether the MT is associated with the development of central adiposity.

DESIGN

Longitudinal analysis from the Study of Women's Health Across the Nation, spanning 1996-2013 (median follow-up 11.8 years).

SETTING

Community-based.

PARTICIPANTS

380 women with regional body composition measures by dual energy X-ray absorptiometry. Mean baseline age was 45.7 years; racial/ethnic composition was 16% Black, 41% Japanese and 43% White.

OUTCOMES

Changes in android, gynoid and visceral fat and waist and hip circumferences.

RESULTS

Android fat increased by 1.21% per year (py) and 5.54% py during premenopause and the MT, respectively (each P < 0.05). Visceral and gynoid fat began increasing at the MT, annualized changes were 6.24% and 2.03%, respectively (each P < 0.05). Postmenopausal annual trajectories decelerated to 1.47% (visceral), 0.90% (android), and -0.87% (gynoid), (all non-zero, P < 0.05). Waist girth grew during premenopause (0.55% py), the MT (0.96% py), and postmenopause (0.55% py) (all non-zero, P < 0.05; not statistically different from each other). Hip girth grew during premenopause (0.20% py) and the MT (0.35% py) (each non-zero, P < 0.05; not statistically different from each other) and decelerated to zero slope in postmenopause. Results are for the White referent; there were statistically significant differences in some trajectories in Black and Japanese women.

CONCLUSIONS

The MT is associated with the development of central adiposity. Waist or hip circumferences are less sensitive to changes in fat distribution.

Changes in abdominal subcutaneous adipose tissue phenotype following menopause is associated with increased visceral fat mass

Menopause is associated with a redistribution of adipose tissue towards central adiposity, known to cause insulin resistance. In this cross-sectional study of 33 women between 45 and 60 years, we assessed adipose tissue inflammation and morphology in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) across menopause and related this to menopausal differences in adipose tissue distribution and insulin resistance. We collected paired SAT and VAT biopsies from all women and combined this with anthropometric measurements and estimated whole-body insulin sensitivity. We found that menopause was associated with changes in adipose tissue phenotype related to metabolic dysfunction. In SAT, postmenopausal women showed adipocyte hypertrophy, increased inflammation, hypoxia and fibrosis. The postmenopausal changes in SAT was associated with increased visceral fat accumulation. In VAT, menopause was associated with adipocyte hypertrophy, immune cell infiltration and fibrosis. The postmenopausal changes in VAT phenotype was associated with decreased insulin sensitivity. Based on these findings we suggest, that menopause is associated with changes in adipose tissue phenotype related to metabolic dysfunction in both SAT and VAT. Whereas increased SAT inflammation in the context of menopause is associated with VAT accumulation, VAT morphology is related to insulin resistance.

Sarcopenic obesity as a determinant of cardiovascular disease risk in older people: a systematic review

BACKGROUND

Aging is associated with body composition changes that include a reduction of muscle mass or sarcopenia and an increase in visceral obesity. Thus, aging involves a muscle-fat imbalance with a shift toward more fat and less muscle. Therefore, sarcopenic obesity, defined as a combination of sarcopenia and obesity, is a global health phenomenon due to the increased aging of the population combined with the increased epidemic of obesity. Previous studies have shown inconsistent association between sarcopenic obesity and the risk of cardiovascular disease (CVD).

AIMS

To systematically review the recent literature on the CVD risks associated with sarcopenic obesity and summarizes ways of diagnosis and prevention.

METHODS

A systematic review of studies that reported the association between sarcopenic obesity and CVD risk in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations.

RESULTS

Risk factors of sarcopenic obesity included genetic factors, aging, malnutrition, sedentary lifestyle, hormonal deficiencies and other molecular changes. The muscle-fat imbalance with increasing age results in an increase in the pro-inflammatory adipokines secreted by adipocytes and a decline in the anti-inflammatory myokines secreted by myocytes. This imbalance promotes and perpetuates a chronic low-grade inflammatory state that is characteristic of sarcopenic obesity. After application of exclusion criteria, only 12 recent studies were included in this review. The recent studies have shown a consistent association between sarcopenic obesity and cardiovascular disease risk although most of the studies are of cross-sectional design that does not confirm a causal relationship. In addition, most of the population studied were of Asian origin which may limit the generalizability of the results. Non-pharmacological interventions by exercise training and adequate nutrition appear to be useful in maintenance of muscle strength and muscle mass in combination with a reduction of adiposity to promote healthy aging.

CONCLUSIONS

Sarcopenic obesity appears to increase the risk of CVD in older people; however, future prospective studies of diverse population are still required. Although non-pharmacologic interventions are useful in reducing the risk of sarcopenic obesity, novel specific pharmacologic agents are lacking.

Chronic binge alcohol and ovariectomy dysregulate omental adipose tissue metaboproteome in simian immunodeficiency virus-infected female macaques

Effective antiretroviral therapy (ART) has significantly reduced mortality of people living with HIV (PLWH), and the prevalence of at-risk alcohol use is higher among PLWH. Increased survival and aging of PLWH is associated with increased prevalence of metabolic comorbidities especially among menopausal women, and adipose tissue metabolic dysregulation may be a significant contributing factor. We examined the differential effects of chronic binge alcohol (CBA) administration and ovariectomy (OVX) on the omental adipose tissue (OmAT) proteome in a subset of simian immunodeficiency virus (SIV)-infected macaques of a longitudinal parent study. Quantitative discovery-based proteomics identified 1,429 differentially expressed proteins. Ingenuity Pathway Analysis (IPA) was used to calculate z-scores, or activation predictions, for functional pathways and diseases. Results revealed that protein changes associated with functional pathways centered around the "OmAT metaboproteome profile." Based on z-scores, CBA did not affect functional pathways of metabolic disease but dysregulated proteins involved in adenosine monophosphate-activated protein kinase (AMPK) signaling and lipid metabolism. OVX-mediated proteome changes were predicted to promote pathways involved in glucose- and lipid-associated metabolic disease. Proteins involved in apoptosis, necrosis, and reactive oxygen species (ROS) pathways were also predicted to be activated by OVX and these were predicted to be inhibited by CBA. These results provide evidence for the role of ovarian hormone loss in mediating OmAT metaboproteome dysregulation in SIV and suggest that CBA modifies OVX-associated changes. In the context of OVX, CBA administration produced larger metabolic and cellular effects, which we speculate may reflect a protective role of estrogen against CBA-mediated adipose tissue injury in female SIV-infected macaques.

Physical Activity Level and Self-Esteem in Middle-Aged Women

Background: Physical activity (PA) is a behavioral modality that may help decrease negative symptoms of menopause and enhance some positive aspects of mental health, including self-esteem. Reduced self-esteem may put menopausal women at higher risk of negative outcomes of menopause and result in a more unpleasant and stressful menopausal experience. The objective of this study was to examine the role of physical activity level on self-esteem in middle-aged women. Methods: Women aged 45-60 from Poland took part in this study. The Rosenberg Self-Esteem Scale, the International Physical Activity Questionnaire, the Menopause Rating Scale and Beck Depression Inventory were used in this study. Results: Among the 111 women, the mean age was 51.7 ± 4.7. The most severe symptoms among studied women concerned sexual problems (1.71 ± 1.5), irritability (1.58 ± 1.37) and joint and muscular discomfort (1.56 ± 1.55). Women with higher total PA level had better self-esteem (p = 0.001). Conclusions: The results of this study showed that physical activity levels can be associated with self-esteem. Most middle-aged women reported high physical activity levels. These results have clinical implications for the inclusion of PA in the lives of middle-aged women to improve self-esteem and mental health.

The Comparison of Physical Activity, Sedentary Behavior, and Mental Health between Early Menopausal Women and Age-Matched General Middle-Aged Women

The current study is to examine the differences in physical activity (PA), sedentary behavior (SB), and mental health (i.e., stress, depression, and suicidal behaviors) between early menopausal women and age-matched general middle-aged women. Among 1348 participants in South Korea, 674 participants who experienced menopause before the age of 45 were defined as the early menopausal group, and 674 women who experienced menopause from 45 years to 55 years were classified as the general group by matching age based on early menopausal women. PA, SB, and mental health were evaluated by using the Global Physical Activity Questionnaire (GPAQ). An independent t-test was used to compare the associations of PA, SB, and mental health between the two groups. To demonstrate the predictors of early menopause, variables in the study were analyzed by multinomial logistic regression. The main findings were that moderate-to-vigorous PA (MVPA) and light PA (LPA) had significant differences between the two groups, but SB had no significant differences. In mental health, only perceived stress had significant differences in this study. The moderate level of stress in the early menopausal group was twice as high as that of the general group, and the severe level of stress was even 2.6 times higher than the general group. PA plays an essential role in mitigating the causes of mortality and the risk of various chronic diseases and improving quality of life; thus, the main findings of this study could be important to provide insights on the corresponding impact between early menopausal women and PA to encourage their healthy lifestyle. Further longitudinal studies are needed to examine the mechanisms underlying the effects of PA, SB, and mental health on early menopausal women.

Circulating myokines IL-6, IL-15 and FGF21 response to training is altered by exercise type but not by menopause in women with obesity

To examine the effects of a time-matched endurance vs. concurrent training on circulating IL-6, IL-13, IL-15, IL-15Ra, FGF21 levels in postmenopausal women with obesity, and to determine these myokines response to endurance training pre- and postmenopause. Thirty-five sedentary postmenopausal women with obesity were randomly divided into endurance training (EN1, N = 10), concurrent training (CON, N = 13) or no training group (CT, N = 12). Additionally, twelve sedentary premenopausal women with obesity were added to an endurance training group (EN2, N = 12). Participants took part in a 12-week supervised intervention, performing 3 sessions/week of 60 min/session. Before and after the interventions, body composition and fitness were assessed, and blood samples obtained to measure serum myokines levels. Total fat mass decreased in all exercised groups (CON,-5.2%; EN1,-5.3%; EN2,-5.6%). In postmenopausal women, serum IL-6, IL-15 and IL-15Ra decreased after training (P<0.01), finding a pronounced reduction in IL-6 (-42% vs. -16%) and IL-15 (-50% vs. -31%) when comparing EN1 to CON (P<0.05). Serum FGF21 was only reduced in the EN1 (-27%; P=0.012). While EN1 and EN2 comparison, reported differences for IL-15Rα concentration (-28% vs. -40%; P=0.023). Finally, in EN2, the delta change of fat mass and IL-6, IL-15 and IL-15Rα were associated (r = 0.605; r = 0.546; r = 0.515; P<0.05). IL-13 showed undetected concentrations. Circulating IL-6, IL-15 and FGF21 response to training is altered by exercise type but not by menopause in women with obesity. Endurance training promotes a higher reduction of these myokines, potentially activating their intricate immune and fat mass regulation roles in postmenopausal women with obesity.

Effects of gonadal status and the estrogen milieu on hypothalamic oxytocin gene expression and serum oxytocin levels in female rats

Oxytocin (OT) and its receptor (OTR) play various roles in the central and peripheral regulation of appetite and body weight. Previously, we have shown that the administration of OT markedly decreased appetite and body weight gain in ovariectomized (OVX) obese rats. In addition, recent studies have shown that the endogenous OT system is also affected by endogenous or exogenous estrogen. In this study, we showed that ovariectomy decreased rats' hypothalamic OT/OTR mRNA and serum OT levels, but did not affect their visceral fat OTR mRNA levels. The chronic administration of estradiol (E2) abrogated these ovariectomy-induced changes; i.e., it increased the rats' hypothalamic OT/OTR mRNA and serum OT levels, and may be associated with reductions in food intake and body weight gain. In addition, acute E2 administration increased the rats' hypothalamic OTR mRNA and serum OT levels, but did not affect their hypothalamic OT mRNA levels. Taken together, these results suggest that endogenous OT and/or OTR expression might be positively regulated by E2 and that the suppressive effects of E2 on appetite and body weight gain might be mediated, at least in part, by the OT system. Thus, we consider that OT might be a target hormone to pursue subsequent interventions of menopause for menopause-induced metabolic disorders.

Nutrition in Menopausal Women: A Narrative Review

Among the various aspects of health promotion and lifestyle adaptation to the postmenopausal period, nutritional habits are essential because they concern all women, can be modified, and impact both longevity and quality of life. In this narrative review, we discuss the current evidence on the association between dietary patterns and clinical endpoints in postmenopausal women, such as body composition, bone mass, and risk markers for cardiovascular disease. Current evidence suggests that low-fat, plant-based diets are associated with beneficial effects on body composition, but further studies are needed to confirm these results in postmenopausal women. The Mediterranean diet pattern along with other healthy habits may help the primary prevention of bone, metabolic, and cardiovascular diseases in the postmenopausal period. It consists on the use of healthy foods that have anti-inflammatory and antioxidant properties, and is associated with a small but significant decrease in blood pressure, reduction of fat mass, and improvement in cholesterol levels. These effects remain to be evaluated over a longer period of time, with the assessment of hard outcomes such as bone fractures, diabetes, and coronary ischemia.

Substrate metabolism during exercise: sexual dimorphism and women's specificities

The aim of this review is to discuss sexual dimorphism of energy metabolism, and to describe the impact of women's hormonal status on substrate oxidation during exercise. Many evidences indicate that sex steroids play a pivotal role in the sex-related differences of body composition and energy substrate storage. Compared with men, women rely more on fat and less on carbohydrates at the same relative exercise intensity. Scientific data suggest that 17-β oestradiol is a key hormone for the regulation of body composition and substrate metabolism. However, in women, measurements with stable isotopic tracers did not highlight any difference in whole-body substrate oxidation rates between the follicular and luteal phases of the menstrual cycle during endurance exercise. The remaining discrepancies about the effect of menstrual cycle-related hormone fluctuations on substrate oxidation could be partly explained by the exercise intensity, which is an important regulator of substrate oxidation. Due to their specific nature and concentration, the synthetic ovarian hormones contained in oral contraceptives also influence substrate metabolism during endurance exercise. However, more studies are needed to confirm that oral contraceptives increase lipolytic activity during endurance exercise without any substantial (or detectable) effect on substrate utilization. Pregnancy and menopause also modify body composition and substrate utilization during exercise through specific hormonal fluctuations.This review highlights that the hormonal status is likely to affect substrate oxidation during exercise in women emphasizing the need to take it into consideration to optimize their health and performance.

Associations of perfluoroalkyl and polyfluoroalkyl substances (PFAS) and PFAS mixtures with adipokines in midlife women

BACKGROUND

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) exposure have been associated with obesity and related comorbidities, possibly through disrupting signaling pathways of adipokines. Both leptin and adiponectin can modulate metabolic processes. However, the effects of PFAS on adipokines are not well understood.

OBJECTIVE

We determined if serum PFAS concentrations were associated with adipokine profiles in midlife women.

METHODS

We examined 1245 women aged 45-56 years from the Study of Women's Health Across the Nation. Concentrations of 11 PFAS were quantified in baseline serum samples collected in 1999-2000. Linear and branched perfluorooctane sulfonic acid isomers (n-PFOS and Sm-PFOS) and their sum (PFOS), linear perfluorooctanoic acid (n-PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonic acid (PFHxS), 2-(N-methyl-perfluorooctane sulfonamido) acetic acid (MeFOSAA), and 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (EtFOSAA) with detection frequencies >60% were included in the analysis. Adipokines including leptin, soluble leptin receptor (sOB-R), free leptin index (FLI, the ratio of leptin to sOB-R), total and high molecular weight (HMW) adiponectin were assessed in 2002-2003. We utilized multivariable linear regressions and Bayesian kernel machine regression (BKMR) to assess individual and overall joint effects of PFAS on adipokines with adjustment for age, race/ethnicity, study site, education, smoking status, physical activity, menopausal status, and waist circumference.

RESULTS

A doubling of PFAS concentrations was associated with 7.8% (95% CI: 2.5%, 13.4%) higher FLI for PFOS, 9.4% (95% CI: 3.7%, 15.3%) for n-PFOA, 5.5% (95% CI: 2.2%, 9.0%) for EtFOSAA and 7.4% (95% CI: 2.8%, 12.2%) for MeFOSAA. Similar associations were found for leptin. Only EtFOSAA was associated with lower sOB-R concentrations (-1.4%, 95% CI: -2.7%, -0.1%). Results remained in women with overweight or obesity but not those with normal weight or underweight. No statistically significant associations were observed with total or HMW adiponectin, except for PFNA with total and HMW adiponectin observed in women with normal weight or underweight. In BKMR analysis, women with PFAS concentrations at the median and the 90th percentile had 30.9% (95% CI: 15.6%, 48.3%) and 52.1% (95% CI: 27.9%, 81.0%) higher FLI, respectively, compared with those with concentrations fixed at the 10th percentile.

CONCLUSION

Some PFAS may alter circulating levels of leptin. Understanding associations between PFAS and adipokines may help elucidate whether PFAS can influence obesity and metabolic disease.

Ginkgo biloba Extract (GbE) Restores Serotonin and Leptin Receptor Levels and Plays an Antioxidative Role in the Hippocampus of Ovariectomized Rats

Since Ginkgo biloba extract (GbE) was reported to improve the hypothalamic serotonergic system of ovariectomized (OVX) rats, the present study aimed to verify the GbE effects on hippocampal oxidative stress, inflammation, and levels of the serotonin transporter (5-HTT), and both the serotonin (5-HT1A, 5-HT1B) and leptin receptors of OVX rats. Two-month-old female Wistar rats had their ovaries surgically removed (OVX) or not (SHAM). After 60 days, OVX rats were gavaged daily with GbE 500 mg kg-1 (OVX+GbE), while SHAM and OVX groups received saline 0.9% (vehicle) for 14 days. Rats were then euthanized, and hippocampi were collected. Both 5-HT1A and 5-HT1B levels were significantly reduced in OVX rats compared to SHAM rats, while 5-HT1A was higher in OVX+GbE rats in comparison to OVX rats. Similarly, LepR levels were increased in OVX+GbE rats compared to OVX rats, reaching similar levels to SHAM rats. Superoxide dismutase activity increased in OVX rats in relation to SHAM rats, which was restored to SHAM levels by GbE treatment. Additionally, GbE significantly increased the glutathione peroxidase activity in comparison to the SHAM group. No differences were observed either in catalase activity or in the levels of 5-HTT, PKCα, TLR-4, NF-κBp50, ERK, and CREB. In summary, our results show a potential effect of GbE on hippocampal pathways involved in feeding behavior, and thus, they suggest that GbE activity might improve menopausal-related hippocampal disorders, offering an alternative therapeutic tool particularly for women to whom hormone replacement therapy may be contraindicated.

EFFECTS OF EXERCISE TYPE AND INTENSITY ON VISFATIN AND THE METABOLIC SYNDROME IN OBESITY

ABSTRACT Objective: Visfatin may regulate a variety of physiological functions and it has great potential to significantly enhance our knowledge of the treatment of metabolic syndrome. Metabolic syndrome (MS) refers to metabolic abnormalities, such as abdominal obesity, dyslipidemia, high low-density cholesterol, high blood pressure and diabetes, and physical activity is an important factor for the management of MS. Therefore, the purpose of this study is to investigate the effects of visfatin on MS and MS risk factors through differences in aerobic exercise intensity and exercise type based on the premise of the same amount of exercise (energy expenditure of 400 kcal per day). Method: Thirty two obese, middle-aged women were randomly assigned to exercise intensity groups VO2max 50% (MAE, n=8) and VO2max 80% (VAE, n=8) and to type of exercise groups VO2max 50% + TRX (MARE, n=8) and VO2max 80% + TRX (VARE, n=8). The exercise program was performed 5 times a week. The data was analyzed using two-way repeated measures ANOVA and post-hoc tests within groups with LSD. Results: Body weight (p<.01 and p<.001) and % body fat (p<.05 and p<.01) significantly decreased in all groups and visfatin only increased significantly after exercise in the VARE group (p<.05). TG, glucose, and waist circumstance (p<.05, p<.01, and p<.001) significantly decreased in all groups and HDL-C (p<.05) only increased significantly after exercise only in the MARE group. Conclusion: These results suggest that, in spite of differences in exercise intensity and exercise type, exercise is effective in improving obesity and MS risk factors, but further research is needed on the exact mechanisms of visfatin. Level of evidence I; Therapeutic Studies Investigating the Results of Treatment .

Estradiol treatment or modest exercise improves hepatic health and mitochondrial outcomes in female mice following ovariectomy

We recently reported that compared with males, female mice have increased hepatic mitochondrial respiratory capacity and are protected against high-fat diet-induced steatosis. Here, we sought to determine the role of estrogen in hepatic mitochondrial function, steatosis, and bile acid metabolism in female mice and investigate potential benefits of exercise in the absence or presence of estrogen via ovariectomy (OVX). Female C57BL mice (n = 6 per group) were randomly assigned to sham surgery (sham), ovariectomy (OVX), or OVX plus estradiol replacement therapy (OVX + Est). Half of the mice in each treatment group were sedentary (SED) or had access to voluntary wheel running (VWR). All mice were fed a high-fat diet (HFD) and were housed at thermoneutral temperatures. We assessed isolated hepatic mitochondrial respiratory capacity using the Oroboros O2k with both pyruvate and palmitoylcarnitine as substrates. As expected, OVX mice presented with greater hepatic steatosis, weight gain, and fat mass gain compared with sham and OVX + Est animals. Hepatic mitochondrial coupling (basal/state 3 respiration) with pyruvate was impaired following OVX, but both VWR and estradiol treatment rescued coupling to levels greater than or equal to sham animals. Estradiol and exercise also had different effects on liver electron transport chain protein expression depending on OVX status. Markers of bile acid metabolism and excretion were also impaired by ovariectomy but rescued with estradiol add-back. Together our data suggest that estrogen depletion impairs hepatic mitochondrial function and liver health, and that estradiol replacement and modest exercise can aid in rescuing this phenotype.NEW & NOTEWORTHY OVX induces hepatic steatosis in sedentary mice which can be prevented by modest physical activity (VWR) and/or estradiol treatment. Estrogen impacts hepatic mitochondrial coupling in a substrate-specific manner. OVX mice have impaired fecal bile acid excretion, which was rescued with estradiol treatment.

Dose-response effects of aerobic exercise on adiposity markers in postmenopausal women: pooled analyses from two randomized controlled trials

BACKGROUND/OBJECTIVE

Exercise may reduce the risk of breast cancer through adiposity changes, but the dose-response effects of exercise volume on adiposity markers are unknown in postmenopausal women. We aimed to compare the dose-response effects of prescribed aerobic exercise volume on adiposity outcomes.

PARTICIPANTS/METHODS

Data from the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) and Breast Cancer and Exercise Trial in Alberta (BETA) were pooled for this analysis (N = 720). These were 12-month randomized controlled trials, where participants were randomized to 225 min/week (mid-volume) of aerobic exercise versus usual inactive lifestyle (ALPHA), or 150 min/week (low-volume) versus 300 min/week (high-volume) (BETA). Fat mass and fat-free mass were measured using DXA and intra-abdominal and subcutaneous fat area were assessed with computed tomography.

RESULTS

After 12 months of aerobic exercise, increasing exercise volumes from no exercise/control to 300 min/week resulted in statistically significant reductions in BMI, weight, fat mass, fat percentage, intra-abdominal and subcutaneous fat area (P < 0.001). Compared with controls, fat mass loss was -1.13, -1.98 and -2.09 kg in the low-, mid- and high-volume groups, respectively. Similarly, weight loss was -1.47, -1.83, -2.21 kg in the low-, mid- and high-volume groups, respectively, compared to controls, and intra-abdominal fat area loss was -7.44, -15.56 and -8.76 cm² in the low-, mid- and high-volume groups, respectively, compared to controls. No evidence for a dose-response effect on fat-free mass was noted.

CONCLUSION

A dose-response effect of exercise volume on adiposity markers was noted, however, the differences in adiposity markers were smaller when comparing 225 min/week to 300 min/week of exercise. Given the strong positive associations between obesity and postmenopausal breast cancer risk, this study provides evidence on the importance of exercise volume as part of the exercise prescription to reduce adiposity and, ultimately, postmenopausal breast cancer risk.

Weight regulation in menopause

IMPORTANCE AND OBJECTIVE

Obesity is a chronic disease of epidemic proportions that continues to affect millions of Americans each year. Postmenopausal women are particularly affected by obesity and have higher rates of severe obesity when compared with their male counterparts. The prevalence of obesity in this population is linked to increased morbidity and mortality and promotes the development and progression of numerous obesity-related health conditions. This review examines the epidemiology, pathophysiology, clinical assessment, and treatment of postmenopausal women with obesity.

METHODS

We have reviewed relevant and up-to-date literature in the MEDLINE database to represent the current understanding of obesity and its effects in this patient population. Articles published between the years 2000 and 2020 were selected for review to represent the most up-to-date evidence on the topic. Search terms used in the PubMed search included women, obesity, menopause, aging, mid-age women, metabolism, weight gain, treatment of obesity, weight loss, bariatric surgery, weight loss medications, diet, physical activity, and behavior modification.

DISCUSSION AND CONCLUSION

Obesity is a complex, chronic, relapsing disease that requires comprehensive assessment and treatment. Obesity is linked to hormonal, lifestyle, and environmental changes that occur during the menopausal transition, and it increases the risk for cardiometabolic disease. The utilization of appropriate clinical evaluation methods to identify obesity in postmenopausal women, and the implementation of effective lifestyle, pharmacotherapeutic, and surgical interventions, have the propensity to reduce the deleterious effects of obesity in this population.

Recent Update on the Molecular Mechanisms of Gonadal Steroids Action in Adipose Tissue

The gonadal steroids, including androgens, estrogens and progestogens, are involved in the control of body fat distribution in humans. Nevertheless, not only the size and localization of the fat depots depend on the sex steroids levels, but they can also highly affect the functioning of adipose tissue. Namely, the gonadocorticoids can directly influence insulin signaling, lipid metabolism, fatty acid uptake and adipokine production. They may also alter energy balance and glucose homeostasis in adipocytes in an indirect way, e.g., by changing the expression level of aquaglyceroporins. This work presents the recent advances in understanding the molecular mechanism of how the gonadal steroids influence the functioning of adipose tissue leading to a set of detrimental metabolic consequences. Special attention is given here to highlighting the sexual dimorphism of adipocyte functioning in terms of health and disease. Particularly, we discuss the molecular background of metabolic disturbances occurring in consequence of hormonal imbalance which is characteristic of some common endocrinopathies such as the polycystic ovary syndrome. From this perspective, we highlight the potential drug targets and the active substances which can be used in personalized sex-specific management of metabolic diseases, in accord with the patient's hormonal status.

Breastfeeding history and the risk of overweight and obesity in middle-aged women

BACKGROUND

The increased metabolic activity required to sustain breastfeeding and its associated milk production helps to reduce maternal fat stores accumulated during pregnancy. This study aims to assess the association between breastfeeding duration and fatness indices in middle-aged women.

METHODS

The analysis was carried out in a group of 7500 parous 55.5 ± 5.3 year old women included body mass index, body fat percentage, and waist-to-height ratio. The likelihood of excessive weight or obesity in relation to total breastfeeding time using multivariate logistic regression analyses.

RESULTS

An analysis of adjusted odds ratios did not show significant associations between breastfeeding duration and the risk of excessive weight and obesity in premenopausal women. After menopause, women who gave birth to 2 children and breastfed 1-6 and > 12 months had a lower risk of abdominal obesity (OR 0.70; 95% CI 0.50-0.99; p = 0.042; and OR 0.68; 95% CI 0.47-0.98; p = 0.039). Women who gave birth to 3 or more children and breastfed for 1-6 months, also showed a lower risk of overweight (OR 0.52; 95% CI 0.27-0.99; p = 0.047), compared to those ones that have never breastfed. There was no relationship found between the duration of lactation and the risk of excessive body fat.

CONCLUSION

Breastfeeding may have some beneficial, long-term effect on the risk of excessive weight and abdominal obesity in women.

Accelerated progression of waist-to-hip ratio but not body mass index associated with lower socioeconomic position: a cohort study of nonobese early postmenopausal Chinese women

OBJECTIVE

Menopausal changes are linked to increase in body fat mass and central fat distribution; nonetheless, the impact of socioeconomic position on such changes has rarely been examined. This cohort study assessed the temporal associations of socioeconomic position with changes in body mass index (BMI) and waist-to-hip ratio (WHR) among early postmenopausal women.

METHODS

Between 2002 and 2004, 518 Hong Kong Chinese women aged 50 to 64 and within 10 years since menopause were recruited and followed up at 3 and 5 years. Weight, height, and waist and hip circumferences were measured by trained interviewers at baseline and follow-up interviews. Socioeconomic positions including educational attainment, economic activity status and household income level, and other baseline demographic characteristics, lifestyle behaviors, and mental health status were collected based on a structured questionnaire. In total, 287 and 267 women with no general and abdominal obesity, respectively, at baseline were included in multiple regression analyses.

RESULTS

Mean intrapersonal increases in BMI and WHR between baseline and 5-year interview were 0.46 kg/m and 2.80%, respectively. Women with no secondary education were 75% more likely to have a greater than-mean WHR increase than their more educated counterparts (P = 0.039). Also, having no secondary education (P = 0.041) and being a homemaker (P = 0.034) had accelerated surge in WHR. Nonetheless, baseline socioeconomic positions were not significantly associated with BMI changes.

CONCLUSIONS

Socioeconomic patterning was observed for the progression of WHR among nonobese Chinese women soon after menopause. Early postmenopausal stage may be a critical window for prevention of abdominal obesity among women with a lower educational attainment.

Association between waist-hip ratio and coronary artery calcification in postmenopausal women

Objective:

Many studies have reported that body composition might be associated with cardiovascular disease, but the issue has not been fully investigated in postmenopausal women.

Methods:

This retrospective study comprised 582 postmenopausal women without a history of cardiovascular disease who visited the Health Promotion Center between May 2008 and February 2018. All women were screened for body fat composition by bioelectrical impedance analysis and for degree of coronary artery calcification (CAC) by multidetector computed tomography. In addition, multivariate analysis, integrated discrimination improvement, and category-free net reclassification improvement were performed.

Results:

The level of triglycerides, and the waist-hip ratio (WHR) in participants with CAC (coronary artery calcium score [CACS] > 0) were higher than in participants with a CACS of zero points. When the participants were stratified into four groups according to WHR, participants with CAC (CACS > 0) increased significantly as WHR quartile increased. A multivariate analysis showed that older age (odds ratio [OR]: 2.539; 95% confidence interval [CI]: 1.524-4.230; P < 0.001), triglyceride level (OR: 1.005; 95% CI: 1.002-1.008; P = 0.003), WHR (OR: 1.103; 95% CI: 1.018-1.195; P = 0.017), and history of hypertension (OR: 2.701; 95% CI: 1.715-4.253; P < 0.001) were significantly associated with CAC. The Brier score upon adding WHR to a clinical model was lower than that of the clinical model without WHR. Adding WHR to a clinical model better predicted CAC than a clinical model without WHR (C index: 0.761, 95% CI: 0.724-0.795, P < 0.001; net reclassification improvement: 0.195, P = 0.037; integrated discrimination improvement: 1.02%, P = 0.043).

Conclusions:

In asymptomatic postmenopausal women, WHR as measured by bioelectrical impedance analysis was significantly associated with coronary atherosclerosis, supplementing information of usual clinical markers. Hence, WHR might be appropriate as a marker for early atherosclerosis.

Association of Oophorectomy and Fat and Lean Body Mass: Evidence from a Population-Based Sample of U.S. Women

BACKGROUND

Bilateral oophorectomy during a nonmalignant hysterectomy is frequently performed for ovarian cancer prevention in premenopausal women. Oophorectomy before menopause leads to an abrupt decline in ovarian hormones that could adversely affect body composition. We examined the relationship between oophorectomy and whole-body composition.

METHODS

Our study population included cancer-free women 35 to 70 years old from the 1999-2006 National Health and Nutrition Examination Survey, a representative sample of the U.S.

POPULATION

A total of 4,209 women with dual-energy x-ray absorptiometry scans were identified, including 445 with hysterectomy, 552 with hysterectomy and oophorectomy, and 3,212 with no surgery. Linear regression was used to estimate the difference in total and regional (trunk, arms, and legs) fat and lean body mass by surgery status.

RESULTS

In multivariable models, hysterectomy with and without oophorectomy was associated with higher total fat mass [mean percent difference (β); β_oophorectomy: 1.61%; 95% confidence interval (CI), 1.00-2.28; β_hysterectomy: 0.88%; 95% CI, 0.12-1.58] and lower total lean mass [β_oophorectomy: -1.48%; 95% CI, -2.67, -1.15; β_hysterectomy: -0.87%; 95% CI, -1.50, -0.24) compared with no surgery. Results were stronger in women with a normal body mass index (BMI) and those <45 years at surgery. All body regions were significantly affected for women with oophorectomy, whereas only the trunk was affected for women with hysterectomy alone.

CONCLUSIONS

Hysterectomy with oophorectomy, particularly in young women, may be associated with systemic changes in fat and lean body mass irrespective of BMI.

IMPACT

Our results support prospective evaluation of body composition in women undergoing hysterectomy with oophorectomy at a young age.

Perils of prolonged ovarian suppression and hypoestrogenism in the treatment of breast cancer: Is the risk of treatment worse than the risk of recurrence?

Premenopausal breast cancer is usually estrogen receptor positive, and hence, prolonged ovarian suppression by medical or surgical means to prevent recurrence has become standard of management to improve disease-free survival. Ten-year adjuvant tamoxifen therapy is associated with 3.5% fewer recurrences compared to five years. The SOFT trial demonstrated small but statistically significant incremental improvements in long-term disease-free survival by the addition of gonadotropin-releasing hormone analog treatment (triptorelin) to an aromatase inhibitor (exemestane). Profound hypoestrogenism in the premenopausal age group may not be well tolerated due to a host of bothersome side effects (primarily vasomotor symptoms, musculoskeletal complaints, genitourinary syndrome of menopause, and mood disorders). Prolonged hypoestrogenism in younger women is associated with premature development of cardiovascular disease, bone loss, cognitive decline, and all-cause mortality. This paper explores multi-system consequences of prolonged hypoestrogenism in premenopausal women derived from studies of women with and without breast cancer. Pretreatment counseling in estrogen receptor positive breast cancer should emphasize the benefit of prolonged estrogen suppression on breast cancer recurrence and established risks of lifelong hypoestrogenism on quality of life and all-cause mortality. Future genomic research may help identify the best candidates for extended ovarian suppression to avoid treating many women when only a minority benefit.

Short-term effects induced by nicotinamide in ovariectomized females

Nicotinamide adenine dinucleotide (NAD)+ precursors such as nicotinamide activate sirtuins and enhance energy metabolism. The aim of this study was to evaluate the metabolic effects of nicotinamide in ovariectomized (OVX) female rats to establish molecular targets against obesity, which support the safe therapeutic application of nicotinamide. The OVX animals were divided into groups: SHAM (simulated surgery), SHAMn (two weeks of 35 mg·kg-1 nicotinamide per day, by gavage), OVX, and OVXn (two weeks of 35 mg·kg-1 nicotinamide per day, by gavage). The results indicated that nicotinamide favored lipolysis, as evidenced by an increase in free fatty acid and hepatic triglyceride levels, which were not fully normalized during the treatment period. The lipolysis appeared to be due to increased SIRT1 and mitochondrial oxidative phosphorylation in muscle and adipose tissue. There were decreases in muscle and fat nicotinamide N-methyltransferase (NNMT), which were associated with decreases in mass and triglyceride, low-density lipoprotein cholesterol (LDLc), and total cholesterol content. Nicotinamide appeared to be beneficial for the glycemic profile, with normal hepatic glycogen storage and a tendency towards insulin sensitivity in the OVXn. In the SHAMn group, nicotinamide led to glucose intolerance, together with reduced muscle expressions of nicotinamide phosphoribosyltransferase (NAMPT) and SIRT3, suggesting that there were no short-term benefits. Supplementation with nicotinamide led to tissue-specific adaptive lipid and molecular changes in OVX rats.

Cajanolactone A, a stilbenoid from Cajanus cajan, inhibits energy intake and lipid synthesis/storage, and promotes energy expenditure in ovariectomized mice

BACKGROUND

We had reported that cajanolactone A (CLA) from Cajanus cajan dose-dependently inhibited ovariectomy-induced obesity and liver steatosis in mice, showing potential to prevent postmenopausal obesity and fatty liver. In this study, the role of CLA in the regulation of energy and lipid homeostasis was investigated.

METHODS

Ovariectomized mice treated with CLA or vehicle for 12 weeks were performed a 48 h monitoring for energy metabolism and food uptake. After that, hypothalami, perigonadal (pWATs), inguinal (iWATs) and brown (BATs) adipose tissues, livers, sera, and fecal and cecal contents were collected and analyzed.

FINDINGS

In CLA-treated mice, we observed reduced food uptake; increased energy expenditure; inhibited expression of orexigenic genes (ORX, ORXR2, pMCH and Gal) in the hypothalami, of lipogenic genes (CD36, SREBP-1c, ChREBP, PPARγ) in the livers, and of lipid storage proteins in the WATs (FSP27, MEST and caveolin-1) and livers (FSP27, Plin2 and Plin5); stimulated expression of metabolism-related proteins (pATGL and Echs1) in the adipose tissues and of thermogenic protein (UCP1) in the inguinal WATs; increased BAT content; increased mitochondria in the pWATs and livers; inhibited angiogenesis in the pWATs; and altered gut microbiome diversity with an increased abundance of Bacteroides.

INTERPRETATION

CLA prevents ovariectomy-induced obesity and liver steatosis via regulating energy intake and lipid synthesis/storage, promoting UCP1-dependent heat production, and protecting the mitochondrial function of hepatocytes and adipocytes. The improved gut microecology and inhibited angiogenesis may also contribute to the anti-obese activity of CLA.

Neck circumference as an independent predictor for NAFLD among postmenopausal women with normal body mass index

BACKGROUND

Neck circumference, a proxy for upper-body subcutaneous fat, is a unique and pathogenic fat depot that confers additional metabolic risk. The purpose of present study was to determine whether neck circumference associates with nonalcoholic fatty liver disease (NAFLD) in postmenopausal women with normal body mass index.

METHODS

A cross-sectional survey (n = 2492) and a 3.1-year follow-up investigation (n = 1354) were conducted among Chinese postmenopausal women with normal BMI (18.5 to < 25 kg/m2). Neck circumference was measured horizontally at the lower margin of the laryngeal prominence.

RESULTS

In the cross-sectional analysis, large neck circumference was associated with the presence of NAFLD (odds ratio 2.28; 95% CI 1.74-2.98; highest tertile versus lowest tertile) after adjustment for confounding factors. Among 1354 subjects without the NAFLD at baseline, 429 (31.7%) incident NAFLD cases occurred at 3.1 years. Neck circumference was positively associated with triglycerides, homeostasis model assessment of insulin resistance, C-reactive protein, and negatively associated with high-density lipoprotein cholesterol and adiponectin. Individuals with large baseline neck circumference had a significantly higher risk of NAFLD than those with small neck circumference. The multivariable adjusted hazard ratio was 1.42 (95% CI 1.15-1.97; p for trend = 0.004) for the highest versus the lowest tertile of neck circumference, and was 1.22 (95% CI 1.10-1.41; p = 0.006) per 1-standard deviation increment in neck circumference.

CONCLUSIONS

Among postmenopausal women with normal BMI, relatively large neck circumference levels are associated with an increased risk of NAFLD.

Targeting insulin resistance with selected antidiabetic agents prevents menopausal associated central obesity, dysglycemia, and cardiometabolic risk

Menopause consequent to reduced circulating estrogen is associated with diminished insulin receptor sensitivity and fat redistribution, particularly central adiposity and increased waist circumference. Peri and menopausal women are at risk of hyperglycemia, prediabetes and attendant metabolic disturbances. Hormone replacement therapy increases insulin receptor sensitivity, but may precipitate an increased cardiovascular risk, depending on the route, if not commenced within the proposed period denoted by the 'timing hypothesis'. The therapeutic ideal of dietary modification with increased physical activity may have compliance issues. We theorize that selected antidiabetic agents reduce visceral fat deposits, restore insulin sensitivity and inhibit inflammatory mediator release. Glucagon-like peptide 1 agonists, sodium-glucose cotransporter 2 inhibitors and even metformin are worthy interventions to treat menopausal-induced obesogenic metabolic conditions. Loss of visceral fat restores insulin receptor sensitivity, decreases central obesity and adipokines to halt dysmetabolic changes.

Sex differences in fat taste responsiveness are modulated by estradiol

Sex as a biological variable has been the focus of increasing interest. Relatively few studies have focused, however, on differences in peripheral taste function between males and females. Nonetheless, there are reports of sex-dependent differences in chemosensitivity in the gustatory system. The involvement of endogenous changes in ovarian hormones has been suggested to account for taste discrepancies. Additionally, whether sex differences exist in taste receptor expression, activation, and subsequent signaling pathways that may contribute to different taste responsiveness is not well understood. In this study, we show the presence of both the nuclear and plasma membrane forms of estrogen receptor (ER) mRNA and protein in mouse taste cells. Furthermore, we provide evidence that estrogen increases taste cell activation during the application of fatty acids, the chemical cue for fat taste, in taste receptor cells. We found that genes important for the transduction pathway of fatty acids vary between males and females and that these differences also exist across the various taste papillae. In vivo support for the effect of estrogens in taste cells was provided by comparing the fatty acid responsiveness in male, intact female, and ovariectomized (OVX) female mice with and without hormone replacement. In general, females detected fatty acids at lower concentrations, and the presence of circulating estrogens increased this apparent fat taste sensitivity. Taken together, these data indicate that increased circulating estrogens in the taste system may play a significant role in physiology and chemosensory cellular activation and, in turn, may alter taste-driven behavior.NEW & NOTEWORTHY Using molecular, cellular, and behavioral analyses, this study shows that sex differences occur in fat taste in a mouse model. Female mice are more responsive to fatty acids, leading to an overall decrease in intake and fatty acid preference. These differences are linked to sex hormones, as estradiol enhances taste cell responsiveness to fatty acids during periods of low circulating estrogen following ovariectomy and in males. Estradiol is ineffective in altering fatty acid signaling during a high-estrogen period and in ovariectomized mice on hormone replacement. Thus, taste receptor cells are a direct target for actions of estrogen, and there are multiple receptors with differing patterns of expression in taste cells.

Abdominal visceral adipose tissue over the menopause transition and carotid atherosclerosis: the SWAN heart study

OBJECTIVES

To characterize abdominal visceral adipose tissue (VAT) trajectory relative to the final menstrual period (FMP), and to test whether menopause-related VAT accumulation is associated with greater average, common carotid artery intima-media thickness (cIMT) and/or internal carotid artery intima-media thickness (ICA-IMT).

METHODS

Participants were 362 women (at baseline: age was (mean ± SD) 51.1 ± 2.8 y; 61% White, 39% Black) with no cardiovascular disease from the Study of Women's Health Across the Nation Heart study. Women had up to two measurements of VAT and cIMT over time. Splines revealed a nonlinear trajectory of VAT with two inflection points demarcating three time segments: segment 1: >2 years before FMP; segment 2: 2 years before FMP to FMP; and segment 3: after FMP. Piecewise-linear random-effects models estimated changes in VAT. Random-effects models tested associations of menopause-related VAT with each cIMT measure separately. Estimates were adjusted for age at FMP, body mass index, and sociodemographic, lifestyle, and cardiovascular disease risk factors.

RESULTS

VAT increased significantly by 8.2% (95% CI: 4.1%-12.5%) and 5.8% (3.7%-7.9%) per year in segments 2 and 3, respectively, with no significant change in VAT within segment 1. VAT predicted greater ICA-IMT in segment 2, such that a 20% greater VAT was associated with a 2.0% (0.8%-3.1%) greater ICA-IMT. VAT was not an independent predictor of ICA-IMT in the other segments or of the other cIMT measures after adjusting for covariates.

CONCLUSIONS

Women experience an accelerated increase in VAT starting 2 years before menopause. This menopause-related increase in VAT is associated with greater risk of subclinical atherosclerosis in the internal carotid artery.

Snacking may improve dietary fiber density and is associated with a lower body mass index in postmenopausal women

OBJECTIVES

This study aimed to examine the relationship between eating frequency (EF), meal frequency, and snacking frequency (SF), and the body weight status of postmenopausal women. We tested how meal frequency and SF were related with macronutrient intake, and how different definitions of snacking affected the study results.

METHODS

Dietary intake was assessed using a 3-d food diary in 302 women age 45 to 65 y. Body weight, body fat percentage, and waist circumference were measured, and the body mass index (BMI) was computed. Women were classified as overweight-to-obese or of normal weight. Eating occasions that provided at least 50 kcal were classified as meals or snacks based on three definitions: Contribution to total energy intake (EI; ≥15% as a meal, <15% as a snack), self-reported, and based on time.

RESULTS

When adjusted for confounders and the EI:estimated energy requirement, a negative association was seen between EF, self-reported SF, and BMI. EF and self-reported SF were negatively associated with EI. Differences in the dietary composition of the snacks between the groups were seen when identified by participants themselves. Specifically, the percentage energy from total sugar and alcohol in self-reported snacks was significantly lower, but dietary fiber density was significantly higher among normal-weight compared with overweight-to-obese women.

CONCLUSIONS

Higher EF and self-reported SF, independently of the EI:estimated energy requirement, is associated with lower BMI values and EI in postmenopausal women. Snacking may improve the dietary fiber density of the diet. An objective definition of snacking needs to be used in nutritional studies.

A prospective study of the relationships between change in body composition and cardiovascular risk factors across the menopause

OBJECTIVE

Menopause increases the risk of cardiovascular disease (CVD) which in part has been attributed to the rise in cholesterol and blood pressure (BP). This study examined the hypothesis that menopausal changes in body composition and regional fat depots relate to the change in CVD risk factors.

METHODS

A prospective recall study was designed to capture premenopausal women to be re-examined soon after menopause. A total of 97 women from the Oxford Biobank underwent dual x-ray absorptiometry, blood biochemistry, and BP readings pre- and postmenopause.

RESULTS

Despite minimal changes in body weight over the 5.1 ± 0.9 year follow-up period, there was an increase in total fat mass and a decline in lean mass, where the proportional change of regional fat mass was the greatest for the visceral fat depot (+22%, P < 0.01). Plasma ApoB (+12%, P < 0.01) and C-reactive protein (+45%, P < 0.01) increased as did systolic (+7%, P < 0.001) and diastolic BP (+5%, P < 0.001). Plasma nonesterified fatty acids decreased (-20%, P < 0.05) which may reflect on a change in adipose tissue function across the menopause. PCSK-9 decreased (-26%, P < 0.01) which suggests a compensation for the postmenopausal reduction in low-density lipoprotein receptor activity. Using multilinear regression analyses the changes in ApoB and diastolic BP were associated with visceral fat mass change, but this association was lost when adjusted for total fat mass change.

CONCLUSION

The increase in CVD risk factor burden across menopause may not be driven by changes in body composition, rather by functional changes in end organs such as adipose tissue and liver.

Women's Wellness with Type 2 Diabetes Program (WWDP): Qualitative findings from the UK and Australian feasibility study

AIMS

To undertake a qualitative study of a multimodal behavioural intervention and research protocol developed to improve wellness in women with type 2 diabetes mellitus (T2DM), the Women's Wellness with Type 2 Diabetes program (WWDP).

METHODS

Semi-structured interviews were conducted with 15 participants who completed the WWDP. The interviews were transcribed verbatim and analysed thematically in an iterative process.

RESULTS

Themes developing from interviews were broadly grouped into three domains, 1) Hope for a better everyday life; 2) Reflection of the program and its contents; and 3) Impacts on health and wellbeing. Participants viewed the WWDP as a necessary and valuable approach that was crucial in helping them adopt strategies to improve their wellbeing and prevent complications associated with T2DM. Some participants expressed ambivalence towards their adherence to the program due to day-to-day life commitments. The most appreciated feature of the program were the individualised approach adopted by the consultation nurse via skype, convenient appointments, the provision of credible and factual information and the accessible website.

CONCLUSIONS

This study critically evaluated perceptions of participants towards the WWDP and provided important recommendations for improving the delivery and sustainability of the program in future. Participants perceived the program as an effective means of supporting their T2DM self-management and improving wellbeing.

Nonalcoholic Fatty Liver Disease: A Global Perspective

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing over the years and is now as high in Asia as in the Western world, so much so that it should no longer be considered a Western disease. In fact, China is expected to have the largest increase in the number of NAFLD cases in the coming years. The increase in prevalence of NAFLD in Asia lags behind that of the Western world; thus, there will be a lag in more severe liver disease in Asia despite a similar prevalence of the disease. NAFLD is more prevalent among patients with diabetes mellitus, which is also an important risk factor for more severe liver disease. Patients with diabetes mellitus thus represent an important target for screening for NAFLD and more severe liver disease. Although the PNPLA3 gene polymorphism is the most studied in NAFLD, it is increasingly clear that the cumulative effect of multiple genes likely predisposes to NAFLD and more severe liver disease in the different ethnic groups, and polygenic risk scores are emerging. Lean NAFLD has been largely reported in Asia but is increasingly recognized worldwide. Multiple risk factors have been identified for the disease that manifests in metabolically unhealthy normal weight individuals; however, it responds to lifestyle intervention, similar to the disease in obese individuals. Lastly, the newer term "metabolic dysfunction-associated fatty liver disease" provides a more accurate reflection of the disease, giving more focus to clinicians and researchers in tackling this increasingly common and challenging disease.

Bone Mineral Density in Different Menopause Stages is Associated with Follicle Stimulating Hormone Levels in Healthy Women

Although estradiol (E2) has been believed to be the most critical factor in the menopause-associated decrease in bone mineral density (BMD), the role of increasing follicle stimulating hormone (FSH) during menopause is relatively unclear. We determined the extent to which hip and lumbar spine BMD differ among the stages of menopause in healthy women, and whether BMD is associated with FSH and E2 levels. A cross-sectional study of 141 healthy women classified as premenopausal (Pre; 38 ± 6 yrs; mean ± SD, n = 30), early perimenopausal (EPeri; 50 ± 3yrs, n = 31), late perimenopausal (LPeri; 50 ± 4yrs, n = 30), early postmenopausal (EPost; 55 ± 3yrs, n = 24), or late postmenopausal (LPost; 62 ± 4 yrs, n = 26), was conducted. Spine/hip BMD and sex hormones were measured using dual-energy X-ray absorptiometry and enzymatic/colorimetric methods, respectively. Compared to EPeri, spine BMD was lower (p < 0.05) in LPeri, EPost, and LPost and hip BMD was lower (p < 0.05) in EPost and LPost. BMD was inversely associated with FSH (spine: r = -0.341; hip: r = -0.271, p < 0.05) and directly associated with E2 (spine: r = 0.274; hip: r = 0.256, p < 0.05). The menopause-related loss of spine and hip BMD is associated not only with low E2 but also higher FSH. Future studies are essential to delineating the mechanisms by which FSH regulates bone health in aging women.

Effects of peripheral oxytocin administration on body weight, food intake, adipocytes, and biochemical parameters in peri- and postmenopausal female rats

Recent studies have revealed that the administration of oxytocin has beneficial effects on the regulation of body weight, food intake, and metabolic functions, especially in obese individuals. Obesity is common in women after the menopause and drives many components of metabolic syndrome. Weight gain in menopausal women has been frequently reported. Although obesity and associated metabolic disorders are frequently observed in peri- and postmenopausal women, there are few medical interventions for these conditions. In this study, we evaluated the effects of chronic oxytocin administration on appetite, body weight, and fat mass in peri- and postmenopausal female rats. Sixteen naturally premenopausal or menopausal rats were intraperitoneally injected with oxytocin (1,000 μg/day) for 12 days. The daily changes in their body weight and food intake were measured at the same time as the oxytocin and vehicle injections. Intraperitoneally administering oxytocin for 12 days significantly reduced food intake, body weight, and visceral adipocyte size. In addition, oxytocin administration caused reductions in serum triglyceride and low-density lipoprotein-cholesterol levels, while it did not disturb hepatic or renal functions or locomotor activity. This is the first study to show the effects of oxytocin on the metabolic and feeding functions of peri- and postmenopausal female rats. Oxytocin might be a useful treatment for metabolic disorders caused by the menopause or aging.

The effects of pre-sleep consumption of casein protein on next-morning measures of RMR and appetite compared between sedentary pre- and postmenopausal women

The purpose of the present study was to compare next-morning responses of RMR and appetite to pre-sleep consumption of casein protein (CP) in pre- and postmenopausal women. The study was a randomised, crossover, double-blind, placebo-controlled trial. Seven sedentary premenopausal (age: 19·9 (sd 1·2) years; BMI: 23·1 (sd 2·6) kg/m2) and seven sedentary postmenopausal (age: 56·4 (sd 4·9) years; BMI: 26·3 (sd 3·5) kg/m2) women participated. During visit one, anthropometrics and body composition were measured. Following visit one, subjects consumed either CP (25 g) or placebo (PL) ≥2 h after their last meal and ≤30 min prior to sleep on the night before visits two and three. Visits two and three occurred ≥1 week after visit one and were 48 h apart. During visits two and three, RMR (VO2), RER and appetite were measured via indirect calorimetry and visual analogue scale, respectively. Anthropometrics and body composition were analysed by one-way ANOVA. RMR and measures of appetite were analysed using a 2 × 2 (menopause status × CP/PL) repeated-measures ANOVA. Significance was accepted at P ≤ 0·05. RMR was significantly lower in postmenopausal compared with premenopausal women under both conditions (P = 0·003). When consumed pre-sleep CP did not alter RMR, RER or appetite compared with PL when assessed next morning in pre- and postmenopausal women. These data contribute to growing evidence that pre-sleep consumption of protein is not harmful to next-morning metabolism or appetite. In addition, these data demonstrate that menopause may not alter next-morning RMR, RER or appetite after pre-sleep consumption of CP.

Body composition and breast cancer risk and treatment: mechanisms and impact

PURPOSE

The purpose of this review is to clarify the association of body composition with breast cancer risk and treatment, including physiological mechanisms, and to elucidate strategies for overcoming unfavorable body composition changes that relate to breast cancer progression.

METHODS

We have summarized updated knowledge regarding the mechanism of the negative association of altered body composition with breast cancer risk and treatment. We also review strategies for reversing unfavorable body composition based on the latest clinical trial results.

RESULTS

Body composition changes in patients with breast cancer typically occur during menopause or as a result of chemotherapy or endocrine therapy. Dysfunction of visceral adipose tissue (VAT) in the setting of obesity underlies insulin resistance and chronic inflammation, which can lead to breast cancer development and progression. Insulin resistance and chronic inflammation are also observed in patients with breast cancer who have sarcopenia or sarcopenic obesity. Nutritional support and a personalized exercise program are the fundamental interventions for reversing unfavorable body composition. Other interventions that have been explored in specific situations include metformin, testosterone, emerging agents that directly target the adipocyte microenvironment, and bariatric surgery.

CONCLUSIONS

A better understanding of the biology of body composition phenotypes is key to determining the best intervention program for patients with breast cancer.

Gender Differences in the Relationships among Metabolic Syndrome and Various Obesity-Related Indices with Nonalcoholic Fatty Liver Disease in a Taiwanese Population

The incidence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide, and it is strongly associated with metabolic syndrome (MetS) and some obesity-related indices. However, few studies have investigated gender differences in these associations. The aim of this study was to investigate associations among MetS and various obesity-related indices with NAFLD, and also look at gender differences in these associations. We enrolled participants who completed a health survey in southern Taiwan. MetS was defined according to the Adult Treatment Panel III for Asians, and the following obesity-related indices were calculated: body mass index (BMI), waist-to-height ratio (WHtR), waist-hip ratio (WHR), lipid accumulation product (LAP), body roundness index (BRI), conicity index (CI), visceral adiposity index (VAI), body adiposity index (BAI), abdominal volume index (AVI), triglyceride-glucose (TyG) index, and hepatic steatosis index (HSI). NAFLD was diagnosed when hepatic steatosis was noted on a liver ultrasound. A total of 1969 (764 men and 1205 women) participants were enrolled. Multivariable analysis showed that both male and female participants with MetS, high BMI, high WHtR, high WHR, high LAP, high BRI, high CI, high VAI, high BAI, high AVI, high TyG index, and high HSI were significantly associated with NAFLD. In addition, the interactions between MetS and gender, WHR and gender, LAP and gender, and TyG index and gender on NAFLD were statistically significant. Among these obesity-related indices, HSI and LAP had the greatest area under the curve in both men and women. Furthermore, stepwise increases in the number of MetS components and the values of indices corresponding to the severity of NAFLD were noted. In conclusion, our results demonstrated significant relationships between MetS and obesity-related indices with NAFLD, and also stepwise increases in the number of MetS components and the values of indices with the severity of NAFLD. MetS, WHR, LAP, and TyG index were associated with NAFLD more obviously in women than in men.

Triglyceride-glucose index is associated with the risk of myocardial infarction: an 11-year prospective study in the Kailuan cohort

Background

The triglyceride–glucose (TyG) index, which is a simple surrogate marker of insulin resistance, has been suggested as a contributor of cardiovascular disease. However, evidence on the effect of long-term elevation of the TyG index exposure on myocardial infarction (MI) is limited. The current study aimed to evaluate the association of baseline and long-term elevation of the TyG index exposure with the risk of MI.

Methods

A total of 98,849 participants without MI at baseline (2006) were enrolled from the Kailuan study. The baseline TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The long-term TyG index was characterized in two ways as follows. The updated mean TyG index was calculated as the mean of TyG index at all previous visits before MI occurred or the end of follow-up; alternatively, the TyG index was calculated as the number of visits with a high TyG index in 2006, 2008, and 2010, ranging from 0 (no exposure) to 3 (had high TyG index at all three study visits). Hazard ratio (HR) and 95% confidence interval (CI) was estimated using multivariable Cox proportion hazard models.

Results

During a median follow-up of 11.03 years, 1555 incident MI occurred. In the multivariable-adjusted model, the risk of MI increased with quartiles of the baseline and updated mean TyG index, the HR in quartile 4 versus quartile 1 was 2.08 (95% CI,1.77–2.45) and 1.58 (1.18–2.12), respectively. Individuals with a high TyG index at all three visits had a 2.04-fold higher risk (95% CI, 1.63–2.56) of MI compared with no exposure. Subgroup analyses showed that the associations were more pronounced in women than in men (P_interaction = 0.0411).

Conclusions

Elevated levels of the baseline and long-term TyG index are associated with an increased risk of MI. This finding indicates that the TyG index might be useful in identifying people at high risk of developing MI.