Age- and menopause-associated variations in body composition and fat distribution in healthy women as measured by dual-energy X-ray absorptiometry

Optimal cutoff values for high-risk waist circumference in older adults based on related health outcomes

The authors aimed to explore optimal cutoffs for high-risk waist circumference (WC) in older adults to assess the health risks of obesity. Prospective data from 4,996 measurements in 2,232 participants aged ≥70 years were collected during 5 triennial measurement cycles (1992/1993-2005/2006) of a population-based cohort study, the Longitudinal Aging Study Amsterdam (Amsterdam, the Netherlands). Cross-sectional associations of WC with pain, mobility limitations, incontinence, knee osteoarthritis, cardiovascular disease, and diabetes were studied. Generalized estimating equations models were fitted with restricted cubic spline functions in order to carefully study the shapes of the associations. Model fits for applying different cutoffs to categorize WC in the association with all outcomes were tested using the quasi-likelihood under the Independence Criterion (QIC). On the basis of the spline regression curves, potential WC cutoffs of approximately 109 cm in men and 98 cm in women were proposed. Based on the model fit, cutoffs between 100 cm and 106 cm were equally applicable in men but should not be higher. In women, the QIC confirmed an optimal cutoff of 99 cm.

Acute sex hormone suppression reduces skeletal muscle sympathetic nerve activity

OBJECTIVES

Comparisons of sympathetic nervous system activity (SNA) between young and older women have produced equivocal results, in part due to inadequate control for potential differences in sex hormone concentrations, age, and body composition. The aim of the present study was to determine the effect of a short-term reduction in sex hormones on tonic skeletal muscle sympathetic nerve activity (MSNA), an indirect measure of whole body SNA, using an experimental model of sex hormone deficiency in young women. We also assessed the independent effects of estradiol and progesterone add-back therapy on MSNA.

METHODS

MSNA was measured in 9 women (30±2 years; mean±SE) on three separate occasions: during the mid-luteal menstrual cycle phase, on the fifth day of gonadotropin-releasing hormone antagonist (GnRHant) administration, and after 5 days add-back of either estradiol (n=4) or progesterone (n=3) during continued GnRHant administration.

RESULTS

In response to GnRHant, there were significant reductions in serum estradiol and progesterone (both p<0.01) and MSNA (25.0±1.9 vs. 19.2±2.4 bursts/min, p=0.04). Continued GnRHant plus add-back estradiol or progesterone resulted in a nonsignificant decrease (19.2±1.7 vs. 12.1±1.9 bursts/min, p=0.07) or increase (16.2±1.7 vs. 21.0±6.0 bursts/min, p=0.39), respectively, in MSNA when compared with GnRHant alone.

INTERPRETATION

The findings of this preliminary study suggest that short-term ovarian hormone suppression attenuates MSNA and that this may be related to the suppression of progesterone rather than estradiol.

Chronic oestrogen replacement in ovariectomised rats attenuates food intake and augments c-Fos expression in the suprachiasmatic nucleus specifically during the light phase

Oestrogen replacement in ovariectomised (OVX) rats has been reported to attenuate food intake, especially during the light phase. To gain better insight into the central mechanism of oestrogen-induced reduction of food intake, we examined the effect of chronic oestrogen replacement in OVX rats on c-Fos expression in the suprachiasmatic nucleus (SCN) and on food intake during the light and dark phases. Eight-week-old female rats were ovariectomised and implanted with either an oestradiol (E2) or a vehicle pellet (Veh) subcutaneously. The animals were housed in an environment with a 12 h light–12 h dark cycle with the lights on at 07.00 hours. The amount of spontaneous food intake relative to each animal's body weight was significantly less for the E2 group than for the Veh group during the light phase, but there were no differences shown between these groups during the dark phase. There were no differences shown in the number of c-Fos-immunoreactive cells in the SCN in the E2 group compared with the Veh group during the early dark phase (22.00 hours; Zeitgeber time 15.00 (ZT15)), but the number was significantly higher than in the Veh group during the early light phase (10.00 hours; ZT3). This finding suggests that chronic oestrogen replacement chronically enhances SCN activity, specifically during the light phase. The oestrogen-induced enhancement of SCN activity during the light phase is possibly involved in the light phase-specific attenuation of food intake by oestrogen replacement in OVX rats.

Ovariectomy and overeating palatable, energy-dense food increase subcutaneous adipose tissue more than intra-abdominal adipose tissue in rats

BACKGROUND

Menopause is associated with increased adiposity, especially increased deposition of intra-abdominal (IA) adipose tissue (AT). This differs from common or 'dietary' obesity, i.e., obesity apparently due to environmentally stimulated overeating, in which IAAT and subcutaneous (S) AT increase in similar proportions. The effect of menopause on adiposity is thought to be due to the decreased secretion of ovarian estrogens. Ovariectomy in rats and other animals is a commonly used model of menopause. It is well known that ovariectomy increases adiposity and that this can be reversed by estradiol treatment, but whether ovariectomy selectively increases IAAT has not been measured directly. Therefore, we used micro-computed tomography (microCT) to investigate this question in both chow-fed and dietary-obese rats.

METHODS

Ovariectomized, ovariectomized and estradiol treated, and sham-operated (intact) rats were fed chow or chow plus Ensure (Abbott Nutrition; n = 7/group). Total (T) AT, IAAT and SAT were measured periodically by microCT. Regional distribution of AT was expressed as IAAT as a percentage of TAT (%IAAT). Excesses in these measures were calculated with respect to chow-fed intact rats to control for normal maturational changes. Chemical analysis of fat was done in chow-fed intact and ovariectomized rats at study end. Data were analyzed by t-tests and planned comparisons.

RESULTS

Body mass, TAT, total fat mass, fat-free body mass, and %IAAT all increased in chow-fed intact rats during the 41 d study. In chow-fed rats, ovariectomy increased excess body mass, TAT, fat mass, fat-free body mass, and SAT, but had little effect on IAAT, in chow-fed rats, leading to a decrease in %IAAT. Ensure feeding markedly increased SAT, IAAT and TAT and did not significantly affect %IAAT. Ovariectomy had similar effects in Ensure-fed rats as in chow-fed rats, although less statistically reliable. Estradiol treatment prevented all the effects of ovariectomy.

CONCLUSIONS

Both ovariectomy in rats and menopause are associated with increased TAT. After ovariectomy, fat is preferentially deposited as SAT and lean body mass increases, whereas after menopause fat is preferentially deposited as IAAT and lean body mass decreases. These opposite effects of ovariectomy and menopause on regional AT distribution and lean body mass indicate that ovariectomy in rats is not a homologous model of menopause-associated changes in body composition that should be used with great caution in investigations of adiposity-related diseases.

The glucocorticoid contribution to obesity

Obesity is fast becoming the scourge of our time. It is one of the biggest causes of death and disease in the industrialized world, and affects as many as 32% of adults and 17% of children in the USA, considered one of the world's fattest nations. It can also cost countries billions of dollars per annum in direct and indirect care, latest estimates putting the USA bill for obesity-related costs at $147 billion in 2008. It is becoming clear that the pathophysiology of obesity is vastly more complicated than the simple equation of energy in minus energy out. A combination of genetics, sex, perinatal environment and life-style factors can influence diet and energy metabolism. In this regard, psychological stress can have significant long-term impact upon the propensity to gain and maintain weight. In this review, we will discuss the ability of psychological stress and ultimately glucocorticoids (GCs) to alter appetite regulation and metabolism. We will specifically focus on (i) GC regulation of appetite and adiposity, (ii) the apparent sexual dimorphism in stress effects on obesity and (iii) the ability of early life stress to programme obesity in the long term.

The contribution of visceral adiposity and mid-thigh fat-rich muscle to the metabolic profile in postmenopausal women

This study explored the relationship between muscle fat infiltration derived from mid-thigh computed tomography (CT) scan, central fat distribution and insulin sensitivity in postmenopausal women. Mid-thigh CT scans were used to measure low attenuation muscle surface (LAMS) (0-34 Hounsfield units (HU)), which represented a specific component of fat-rich muscle. Whole-body insulin sensitivity (M/I) was evaluated by an euglycemic-hyperinsulinemic clamp. A group of 103 women aged 57.0 ± 4.4 years was studied. Women with higher levels of LAMS presented higher metabolic risk features, particularly elevated fasting, 2-h plasma glucose (2hPG) concentrations and diminished M/I (P < 0.05). To further study the contribution of muscle fat infiltration and central adiposity on metabolic parameters, we divided the whole group based on the median of LAMS and visceral adipose tissue (VAT). As expected, the best metabolic profile was found in the Low-LAMS/Low-VAT group and the worst in the High-LAMS/High-VAT group. Women with Low-LAMS/High-VAT presented similar metabolic risks to those with High-LAMS/High-VAT. There was no difference between High-LAMS/Low-VAT and Low-LAMS/Low-VAT, which presents the most healthy metabolic and glycemic profiles as reflected by the lowest levels of cardiovascular disease risk variables. This suggests that High-LAMS/Low-VAT is also at low risk of metabolic deteriorations and that High-LAMS, only in the presence of High-VAT seems associated with deteriorated risks. Although increased mid-thigh fat-rich muscle was related to a deteriorated metabolic profile, VAT appears as a more important contributor to alterations in the metabolic profile in postmenopausal women.

Eating frequency is associated with energy intake but not obesity in midlife women

Midlife women tend to gain weight with age, thus increasing risk of chronic disease. The purpose of this study was to examine associations between overweight/obesity and behavioral factors, including eating frequency, in a cross-sectional national sample of midlife women (n = 1,099) (mean age = 49.7 years, and BMI = 27.7 kg/m²). Eating behaviors and food and nutrient intakes were based on a mailed 1-day food record. BMI was calculated from self-reported height and weight, and level of physical activity was assessed by self-reported questionnaire. After exclusion of low-energy reporters (32% of sample), eating frequency was not associated with overweight/obesity (P > 0.05) and was not different between BMI groups (normal, 5.21 ± 1.79; overweight, 5.16 ± 1.74; obese, 5.12 ± 1.68, P = 0.769). Adjusted logistic regression showed that eating frequency, snacking frequency, breakfast consumption, eating after 10 PM and consuming meals with children or other adults were not significantly associated with overweight/obesity. Total energy intake increased as eating frequency increased in all BMI groups, however, obese women had greater energy intake compared to normal weight women who consumed the same number of meals and snacks. Intake of fruit and vegetables, whole grains, dietary fiber, dairy, and added sugars also increased as eating frequency increased. While eating frequency was not associated with overweight/obesity, it was associated with energy intake. Thus, addressing total energy intake rather than eating frequency may be more appropriate to prevent weight gain among midlife women.

Use of knee height for the estimation of stature in elderly Turkish people and their relationship with cardiometabolic risk factors

The determination of the approximately truest value in height measurement is important in many fields, but it is difficult to perform true measurements, especially in the elderly individuals. We planned to investigate the following items in geriatric Turkish population: to calculate the decrease in height with advancing age by using the standing height measurement and estimated height derived from the knee height; to evaluate the significance of difference between the two measurement methods in the calculation of body mass index (BMI) and waist/height ratio (WHtR); to determine the cut-off value of WHtR according to estimated height in elderly individuals. We studied 551 cases aged between 19 and 97 years. Knee height was measured using a sliding caliper in a sitting position. Linear regression analysis was carried out to derive predictive equations for the estimation of stature with adults (≤ 50 years of age) according to the gender. This equation was then used to estimate height among elderly subjects. Of the cases, 60.3% were <60 years (mean: 48.75 ± 7.50); 39.7% of the cases were >60 years (mean: 69.51 ± 7.12). Estimated BMI (EBMI) measurements in the females and males >60 years were in average 1.23 kg/m(2) and 0.92 kg/m(2) higher than their real BMIs, respectively. EBMI measurements in the females <60 years were 0.32 kg/m(2) higher than their real BMIs (p<0.01). There is a statistically significant difference between WHtR in the females of both age groups, and in the males >60 years, as compared to our estimated WHtR (EWHtR) measurements (p<0.01). The cut-off point of WHtR was 0.61 and 0.58 in the female and male cases of >60 years in our study, respectively. WHtR seemed to be a better anthropometric index that could predict most cardiometabolic risk factors in our study. EWHtR emerged to be a better cardiometabolic risk index especially in the elderly group.

Significant associations of age, menopausal status and lifestyle factors with visceral adiposity in African-American and European-American women

BACKGROUND

Elevated visceral adiposity is strongly predictive of cardiometabolic disease, but, due to the high cost of biomedical imaging, assessment of factors contributing to normal variation in visceral (VAT) and subcutaneous (SAT) adipose tissue partitioning in large cohorts of healthy individuals are few, particularly in ethnic and racial minority populations.

OBJECTIVE

To describe age, menopausal status, smoking and physical activity differences in VAT and abdominal subcutaneous adipose tissue (ASAT) mass in African-American (AA) and European-American (EA) women.

METHODS

Magnetic resonance imaging measures of VAT and ASAT mass and VAT% (VAT/VAT+ASAT, %) were obtained from a cross-sectional sample of 617 EA and 111 AA non-diabetic women aged 18-80 years. Multivariate linear regression was used to test independent effects of the covariates.

RESULTS

VAT and VAT% were higher in EA than AA women (p < 0.01). Differences in VAT, ASAT and VAT% across age groups began in early adulthood in both ethnic groups, but the association of age with VAT% was stronger in EA women (p for interaction = 0.03). Current smokers had higher VAT and VAT% (p < 0.01) and lower TBF than non-smokers. Frequent participation in sports activities was associated with ∼30% lower VAT in older (>55 years) as well as younger ( < 40 years) women (p < 0.0001).

CONCLUSION

Greater allocation of abdominal adipose tissue into the visceral compartment occurs in EA than AA women and in older than younger women. Avoidance of cigarette smoking and frequent participation in sports activities may partially counteract this deleterious phenomenon of ageing.

Reproductive hormones and obesity: 9 years of observation from the Study of Women's Health Across the Nation

The effect of change in reproductive hormones and menopause on incident obesity (body mass index > or =30 kg/m(2)) and severe obesity (body mass index > or =35 kg/m(2)) was evaluated over 9 years in 3,260 US women recruited in the multiethnic Study of Women's Health Across the Nation in 1996-1997. After 9 years, cumulative incidences of obesity and severe obesity reached 21.8% and 12.3%, respectively. In multivariate analysis, hormone changes, chronic health conditions, lower physical activity, race/ethnicity, and age were significantly associated with incident obesity and/or severe obesity. The odds of incident severe obesity increased with surgical menopause (odds ratio (OR) = 5.07, 95% confidence interval (CI): 2.29, 11.20; P < 0.001) and initiation of hormone therapy prior to 12 months of amenorrhea (OR = 2.94, 95% CI: 1.14, 7.58; P = 0.03). Predictors of obesity included an increase in free androgen index (OR = 1.37, 95% CI: 1.12, 1.68; P = 0.002) and a decrease in sex hormone-binding globulin (OR = 0.60, 95% CI: 0.45, 0.80; P = 0.0005). Similar results were found for severe obesity. Obesity rates varied by race, but no hormone-by-race interactions were observed. These longitudinal data demonstrate that higher androgens, lower sex hormone-binding globulin, surgical menopause, and early hormone therapy use predict incident obesity and/or severe obesity in a multiracial cohort of women transitioning into menopause.

Physical activity and reduced intra-abdominal fat in midlife African-American and white women

The purpose of our study was to determine whether self-reported physical activity (PA), including recreational, household, and exercise activities, is associated with intra-abdominal fat (IAF) in community-dwelling white and black midlife women. We performed a cross-sectional study of 369 women from the Chicago site of the Study of Women's Health Across the Nation (SWAN) ancillary study, the SWAN Fat Patterning Study. PA level was the independent variable, and IAF, assessed by computerized tomography (CT) scan, was the dependent variable. Measures were obtained at SWAN Fat Patterning Baseline visit between August 2002 and December 2005. Linear regression models explored the association between PA and IAF. The first model included IAF as the outcome and total score PA as the main predictor, adjusting for total percent fat mass, age, and ethnicity. The second model included education, parity, sex hormone-binding globulin (SHBG) level, and depressive symptoms, measured by Center for Epidemiological Studies-Depression (CES-D) scale. Each 1-point higher total PA score was associated with a 4.0 cm(2) lower amount of IAF (P = 0.004), independent of total percent fat mass, age, ethnicity, SHBG level, educational level, CES-D, and parity. Associations did not differ between white and black women. This study demonstrates a significant negative association between PA and IAF independent of multiple covariates in midlife women. Our findings suggest that motivating white and black women to increase PA during midlife may lessen IAF, which may have a positive impact on subsequent development of diabetes and cardiovascular disease.

Impact of walking on adipose tissue lipoprotein lipase activity and expression in pre- and postmenopausal women

OBJECTIVE

The aim of this study was to examine regional variation in adipose tissue lipoprotein lipase (AT-LPL) activity and expression in pre-and postmenopausal women, before and after training, once differences in chronological age or obesity degree are taken into account.

METHODS

Sixteen late pre- and 14 early postmenopausal (49 +/- 2 vs. 52 +/- 2 years; p < 0.001) moderately obese women (body mass index 29-35 kg/m(2)) were subjected to a 16-week walking program (3 sessions/week of 45 min at 60% heart rate reserve). Abdominal and femoral AT-LPL activity and expression, fasting lipid-lipoprotein profile, body composition, and cardiorespiratory fitness (CRF) were measured before and after our intervention. Statistical analyses were performed using covariance analysis for age differences.

RESULTS

AT-LPL activity and expression, lipid-lipoprotein metabolism, body fatness, and CRF were similar at baseline, irrespective of the group considered. Slight reductions in plasma cholesterol and high-density lipoprotein (HDL) cholesterol levels, fat mass and waist girth reductions, CRF increases as well as femoral AT-LPL activity and expression decreases after our intervention were comparable, regardless of menopausal status (0.0001 < p < 0.05).

CONCLUSIONS

Lipid storage is decreased in the femoral depot after walking, regardless of menopausal status. Reduction in AT-LPL activity or expression does not lead to a more deleterious lipid-lipoprotein profile, despite the modest decrease noted in HDL cholesterol concentrations.

Associations between gender, age and waist circumference

In December 2008, the World Health Organization (WHO) convened a consultation to discuss cut-points for waist circumference (WC). As part of that effort, this paper examines the impact of gender and age on WC. As WC is influenced by body weight, body composition and fat distribution, their associations with gender and age were reviewed. We also noted the relationships with sex hormones, parity and menopause. We then summarized data on gender, age and WC. This presentation is not intended to be comprehensive, but to provide an overview of the available research. There are large differences in body composition in men and women, with women having more body fat. Fat distribution also differs with gender, with men having a relatively more central distribution of fat. These differences begin early in life and become more apparent in puberty due to changes in sex hormone levels. In both, men and women, waist and waist-to-hip ratio increase with age. A large portion of this increase is driven by gains in body weight, but the increases observed are larger than those that would be predicted from increases in the body mass index alone, and increases in WC are seen with aging in the absence of weight gain. The current practice of using seperate waist cut-points by gender is appropriate. Although WC increases with age, so does the risk of many chronic diseases. An evaluation of the need for age-specific waist cut-points in adults would need to consider disease risk.

Type 2 diabetes mellitus and other cardiovascular risk factors are no more common during menopause: longitudinal study

OBJECTIVE

The aim of this study was to undertake a prospective study of the changes in certain risk factors for cardiovascular disease occurring during menopause.

METHODS

A longitudinal cohort study of 475 women was followed up for 6 years (Pizarra Study). The final menstrual period was defined after at least 6 months of amenorrhea. The women were classified into three groups: group 1, no menopause at either the first or second study; group 2, no menopause at the first study but menopause at the second study (6 y later); and group 3, menopause at the first study (and also at the second). The following are the main outcome measures used: age; body mass index; waist circumference; waist-to-hip ratio; skinfold thickness; arm circumference; intake of macronutrients (quantitative questionnaire); systolic and diastolic blood pressures; cholesterol, triglycerides; high-density lipoprotein cholesterol; uric acid; homeostasis model assessment of insulin resistance; and the prevalence of obesity, hypertension, type 2 diabetes mellitus, impaired glucose tolerance, and impaired fasting glucose.

RESULTS

None of the cardiovascular risk factors studied changed during the passage from premenopause to postmenopause, independently of age or physical activity.

CONCLUSIONS

Menopause is a biological condition of the human species, for which has recently received attempts at medicalization that were not always justified. If menopause is not accompanied by any other cardiovascular risk factor independently of age, the stigma of menopause being considered a risk factor should cease. Although the results have the strength of a prospective study, the sample size forced us to consider these findings as preliminary.

Influence of menopause on diabetes and diabetes risk

Many postmenopausal women live with diabetes mellitus; however, little information is available about how the changes that occur around the time of menopause might uniquely affect management of diabetes mellitus in this population. Although the weight gain that commonly occurs during the menopausal transition is largely attributable to aging rather than the transition itself, changes in body composition have been independently associated with menopausal status. These changes in body composition have, in turn, been associated with alterations in insulin sensitivity and glucose metabolism in postmenopausal women. Hormone therapy seems to have neutral or beneficial effects on the adverse changes in body composition associated with menopause. Whether menopausal status independently influences diabetes risk remains controversial. Nevertheless, consistent findings from large clinical trials suggest that postmenopausal hormone therapy decreases the risk of developing diabetes mellitus. Similarly, many studies suggest that postmenopausal hormone therapy has neutral or beneficial effects on glycemic control among women already diagnosed as having diabetes mellitus. Future studies are needed to elucidate the mechanisms that underlie these relationships and to determine how these observations should influence recommendations for the care of postmenopausal women with diabetes mellitus.

Adipocyte size predicts incidence of type 2 diabetes in women

Enlarged subcutaneous abdominal adipocytes have been shown to predict incidence of type 2 diabetes (T2D) in the Pima population of Arizona (USA). We investigated the role of subcutaneous abdominal adipocyte size (AAS), as well as femoral adipocyte size (FAS), as predictors of T2D in a population-based Swedish cohort. In 1974-1975, a sample of 1302 middle-aged women underwent a health examination, including anthropometry and evaluation of parental medical history. In addition, body composition (total body potassium and total body water), AAS and FAS (adipose tissue needle biopsy) were assessed in a subsample of 245 women. Incidence of T2D was followed until 2001, with 36 cases eligible for inclusion in this analysis. Women developing T2D had larger AAS at baseline vs. women remaining healthy (age/heredity-adjusted hazard ratio for increase of AAS by 1 sd [AAS-HR] 1.91; P<0.001). Further adjustment for both body fat percentage and waist-to-height ratio (WHtR) indicated a robust association. For FAS, the corresponding associations were consistently weaker. WHtR retained a strong predictive association independent of AAS and FAS (WHtR-HR 2.6 and 2.7, respectively; P<0.001). To conclude, in addition to the amount and distribution of body fat in women, subcutaneous adipocyte size, particularly in the abdominal region, predicts incidence of T2D in later life.

Offspring consume a more obesogenic diet than mothers in response to changing socioeconomic status and urbanization in Cebu, Philippines

Background

Overweight increased among Filipino mothers and offspring from 1994 to 2005 however, a higher rate of increase among mothers resulted in a prevalence 4 times higher than that among offspring in 2005. Our aim was to explore the differential effects of changing income, assets, maternal education, and urbanicity on dietary behaviors of mothers and offspring that may affect overweight risk.

Methods

The study included a cohort of Filipino offspring and their mothers participating in the Cebu Longitudinal Health and Nutrition Survey at four time points from 1994 (n = 1,885 pairs) to 2005 (n = 1,349 pairs). The effect of socioeconomic factors and urbanicity, on dietary behaviors including energy adequacy, percent fat and carbohydrates were examined using longitudinal random-effects regression models.

Results

Mothers and offspring were consistently more likely to consume more calories relative to basal needs as well as a higher percent of calories from fat and a lower percent from carbohydrates with higher socioeconomic status and urbanization. Despite the substantially higher rates of overweight among mothers compared to offspring, offspring consumed a significantly more obesogenic diet than mothers experiencing the same increases in wealth and urbanicity.

Conclusion

Family-based interventions should be developed to counteract the shift towards a more obesogenic diet observed for both Filipino mothers and offspring.

Hypothalamic neuronal histamine signaling in the estrogen deficiency-induced obesity

Menopause is one of the triggers that induce obesity. Estradiol (E2), corticotropin-releasing hormone (CRH), and hypothalamic neuronal histamine are anorexigenic substances within the hypothalamus. This study examined the interactions among E2, CRH, and histamine during the regulation of feeding behavior and obesity in rodents. Food intake was measured in rats after the treatment of E2, alpha-fluoromethyl histidine, a specific suicide inhibitor of histidine decarboxylase that depletes hypothalamic neuronal histamine, or CRH antagonist. We measured food intake and body weight in wild-type mice or mice with targeted disruption of the histamine receptors (H1-R) knockout (H1KO mice). Furthermore, we investigated CRH content and histamine turnover in the hypothalamus after the E2 treatment or ovariectomy (OVX). We used immunohistochemical staining for estrogen receptors (ERs) in the histamine neurons. The E2-induced suppression of feeding was partially attenuated in rats pre-treated with alpha-fluoromethyl histidine or CRH antagonist and in H1KO mice. E2 treatment increased CRH content and histamine turnover in the hypothalamus. OVX increased food intake and body weight, and decreased CRH content and histamine turnover in the hypothalamus. In addition, E2 replacement reversed the OVX-induced changes in food intake and body weight in wild-type mice but not in H1KO mice. Immunohistochemical analysis revealed ERs were expressed on histamine neurons and western blotting analysis and pre-absorption study confirmed the specificity of ER antiserum we used. These results indicate that CRH and hypothalamic neuronal histamine mediate the suppressive effects of E2 on feeding behavior and body weight.

Estradiol and the control of food intake

Gonadal steroids are among the many factors that influence food intake and body weight in mammals. Hormonal effects on these processes are particularly striking in female rats, which show large increases in food intake and body weight after ovariectomy. A key role of estradiol in the control of food intake and energy balance in humans is evidenced by the fact that the incidence of obesity increases greatly after menopause [American College of Obstetricians and Gynecologists. Body mass index and insulin resistance. Obstet Gynecol 2004;104:5s-10]. The actions of estradiol on neural systems that regulate eating may also account in part for sex differences in food intake and eating disorders, which occur much more frequently in young women [Sodersten P, Bergh C. Anorexia nervosa: towards a neurobiologically based therapy. Eur J Pharmacol 2003;480:67-74]. This paper presents a minireview of research examining the changes in feeding that occur during the ovarian cycle, the effects of estradiol withdrawal and replacement on food intake and body weight, and the neurobiological mechanisms by which estradiol influences feeding behavior. A model of hormone action on food intake that emerges from this research views estradiol as an indirect control of eating and meal size, producing changes in feeding behavior by modulating the central processing of both satiating and orexigenic peptides that represent direct controls of eating. Some of the shortcomings of the model and directions for future research are discussed.

Longitudinal changes in abdominal fat distribution with menopause

Increases in abdominal fat have been reported with menopause, but the impact of menopause on abdominal fat distribution (visceral vs subcutaneous) is still unclear. The objective of the study was to determine if abdominal fat content (volume) or distribution is altered with menopause. Magnetic resonance imaging was used to quantify total abdominal, subcutaneous, and visceral fat in 8 healthy women, both in the premenopausal state and 8 years later in the postmenopausal state. Physical activity (PA) and blood lipids were also measured. Body weight and waist circumference did not change with menopause (pre- vs postmenopause: body weight, 63.2 +/- 3.1 vs 63.9 +/- 2.5 kg; waist circumference, 92.1 +/- 4.6 vs 93.4 +/- 3.7 cm); however, total abdominal fat, subcutaneous fat, and visceral fat all significantly (P < .05) increased with menopause (pre- vs postmenopause: total, 27 154 +/- 4268 vs 34 717 +/- 3272 cm(3); subcutaneous, 19 981 +/- 3203 vs 24 918 +/- 2521 cm(3); visceral, 7173 +/- 1611 vs 9798 +/- 1644 cm(3)). Although absolute adiposity changed with menopause, relative fat distribution was not significantly different after menopause (pre- vs postmenopause: subcutaneous, 73% +/- 3% vs 71% +/- 3%; visceral, 26% +/- 3% vs 28% +/- 3%). Lean mass, fat mass, and PA, along with total cholesterol and triglyceride levels, did not change with menopause. High-density lipoprotein and low-density lipoprotein both increased (P < .05), and the ratio of total cholesterol to high-density lipoprotein decreased (P < .05) with menopause. As measured longitudinally with magnetic resonance imaging, total abdominal fat content increased with menopause despite no change in PA, body weight, or waist circumference; however, menopause did not affect the relative abdominal fat distribution in these women.

Effect of body fat stores on total and regional bone mineral density in perimenopausal Chinese women

Accumulation of body fat is known to be beneficial to bone mass through increased body weight. However, not all the skeleton is loaded by body weight. Therefore, we assume that fat stores would exert different effects on bone mass at different skeletal sites. In this study, 84 perimenopausal Chinese women were recruited. Using dual-energy X-ray absorptiometry, total body fat mass (TBFM), total body lean mass (TBLM), percent body fat (PBF), and total body and regional bone mineral density (BMD) were measured. Correlation analysis indicated that PBF correlated negatively with BMD at ribs and both arms (all P < 0.05). After adjusting for TBLM, PBF had a significantly negative correlation with BMD at head, ribs, both arms, and whole body (all P < 0.05). With adjustment for body weight and height, a significantly negative correlation between PBF and BMD was present, not only at ribs and arms but also at legs and whole body (all P < 0.05, except right leg, at P = 0.094). There was a significantly positive correlation between body weight and leg BMD (all P < 0.001). Body weight was positively correlated with TBFM (r (2) = 0.783, P < 0.001) and TBLM (r (2) = 0.770, P < 0.001). Based on the results, we conclude that increased body fat stores would exert a detrimental effect on BMD, but this effect is more prominent on non-weight-bearing bone. On weight-bearing bone, the detrimental effect of increased body fat could be offset or outweighed by the beneficial effect of increased body weight.

A polymorphism of apolipoprotein E (APOE) gene is associated with age at natural menopause in Caucasian females

OBJECTIVE

The present study aimed to investigate possible association of the apolipoprotein E (APOE) gene polymorphisms with age at natural menopause (ANM) in Caucasian females.

DESIGN

Four SNPs (including two replacements, SNP3 Cys112Arg and SNP4 Arg158Cys) were genotyped in 253 randomly selected unrelated Caucasian women having experienced natural menopause. The comprehensive statistical analyses focusing on the association of the APOE gene and some environmental factors with ANM were conducted.

RESULTS

Alcohol consumption was a significantly predictor of earlier natural menopause (P<0.05). One SNP (rs769450) was significantly associated with ANM according to both population based and the transmission disequilibrium test (TDT) analyses (P=0.007 and 0.046, respectively). However, no association was observed between APOE varepsilon2, varepsilon3, varepsilon4 and ANM.

CONCLUSIONS

Genetic variation in the APOE gene may influence the variation in ANM in Caucasian women.

A Lifestyle Approach for Primary Cardiovascular Disease Prevention in Perimenopausal to Early Postmenopausal Women

Cardiovascular disease (CVD) is the leading cause of death among women in the United States. A large proportion of deaths attributable to CVD occur in asymptomatic women, making early detection and diagnosis difficult. As a result, women tend to be diagnosed at later stages of disease when compared with men. In addition, women have not experienced as great a decline in CVD mortality in recent decades as have men. Therefore, the development of primary CVD prevention strategies to decrease the CVD risk in women has become a major public health priority and creates the need for alternate strategies to be developed to decrease CVD risk in women. The success of a nonpharmacological, lifestyle approach for primary CVD prevention has recently been demonstrated in perimenopausal to early postmenopausal women. Two clinical trials, the Women's Healthy Lifestyle Project (WHLP) and Women On the Move through Activity and Nutrition (WOMAN) study, examined the role of lifestyle to prevent unfavorable CVD risk factor changes that typically occur as a woman transitions through menopause. In both studies, a lifestyle intervention approach, with modest dietary restrictions and increased leisure physical activity, was effective for weight loss and/or weight maintenance and CVD risk factor reduction. More research is needed to determine the long-term benefits of a lifestyle intervention to prevent CVD in women. The existing evidence suggests that the promotion of healthy lifestyle practices by health care providers is a valuable strategy for CVD risk factor reduction in women transitioning through menopause.

Relationship between blood adipocytokines and resting energy expenditure in young and elderly women

It has been demonstrated in a previous study that resting energy expenditure (REE) is associated with adiponectin levels in the blood. However, body composition was not taken into consideration in that study. The purpose of the present study was to again investigate the relationship between blood adipocytokines and REE, adjusted by body composition, in both young and elderly women. REE and blood adipocytokines were measured in 115 young (age: 22.3+/-2.1 y, BMI: 21.3+/-1.9 kg/m(2)) and 71 elderly (63.4+/-6.5 y, 22.9+/- 2.3 kg/m(2)) women. Dual energy X-ray absorptiometry was used to measure percent body fat. Fat mass and fat free mass (FFM) were calculated. REE (kcal/d and kcal/kg BW/d) was lower in elderly women than in young women, but no significant difference was observed in REE, expressed as kcal/kg FFM/d, between the two groups. Although elderly women had a higher percent body fat and higher serum leptin concentrations than young women, plasma adiponectin concentrations did not differ between young and elderly women. In elderly women, REE (kcal/d) was significantly and inversely correlated with plasma adiponectin concentration (r=-0.386, p<0.001), but REE expressed per kilogram of BW or FFM was not significantly correlated. Furthermore, no significant correlation was observed between REE (kcal/d) and concentrations of plasma adiponectin or serum leptin, after adjusting for potential confounders such as body composition and hormones, in either age group. These results suggest that adipocytokines do not influence REE in adult women.

Oxidative stress, body fat composition, and endocrine status in pre- and postmenopausal women

OBJECTIVE

To evaluate the role of menopause on the regional composition and distribution of fat in women and eventual correlations with the oxidative state.

DESIGN

In this observational clinical investigation, 90 women (classified for menopause status according to Stages of Reproductive Aging Workshop criteria) were evaluated for body mass composition and fat distribution by dual-energy x-ray absorptiometry and for oxidative status by determination of serum hydroperoxide levels and residual antioxidant activity.

RESULTS

Total body fat mass increases significantly in postmenopause (P < 0.05) by 22% in comparison with premenopause, with specific increases in fat deposition at the level of trunk (abdominal and visceral) (P < 0.001) and arms (P < 0.001). Concomitantly, the antioxidant status increases significantly (P < 0.001) by 17%. When data were adjusted for age by analysis of covariance, statistical significance disappeared for the increase in fat mass, but it was retained for antioxidant status (P < 0.05). Both antioxidant status and hydroperoxide level increased with trunk fat mass, as shown by linear correlation analysis (r = 0.46, P < 0.001 and r = 0.26, P < 0.05, respectively).

CONCLUSIONS

The results of our investigation demonstrate that fat content increases in the upper part of the body (trunk and arms) in postmenopause and that age is the main determinant of this increase. During the comparison of premenopausal and postmenopausal women, we also detected a significant increase in antioxidant status. Apparently this change is mainly related to menopausal endocrine and fat changes.

Higher levels of central adiposity in healthy premenopausal women with family histories of premenopausal breast cancer

Research strongly suggests that lower overall adiposity and higher central adiposity are independent risk factors for premenopausal breast cancer in the general population. We aimed to test the possibility that these factors may contribute to familial risk of premenopausal breast cancer. A convenience sample of healthy women, ages 25-49, was recruited to yield three study groups: (1) Women with first-degree family histories of premenopausal breast cancer, operationally defined as being diagnosed prior to age 50 (Group FH < 50, n = 39); (2) Women with first-degree family histories of postmenopausal breast cancer, operationally defined as being diagnosed at age 50 or after (Group FH > or = 50, n = 33); and (3) Women without a history of breast cancer in first-degree relatives (Group FH-, n = 132). Multinomial logistic regression analyses, including possible confounders, waist circumference, and BMI, revealed a lower BMI among FH < 50 compared to either FH- (OR = 0.72; 95% CI = 0.59-0.87), or FH > or = 50 women (OR = 0.75; 95% CI = 0.60-0.95), and higher waist circumferences in FH < 50 compared to either FH- (OR = 1.15; 95% CI = 1.06-1.25), or FH > or = 50 women (OR = 1.16; 95% CI = 1.05-1.28). No group differences were seen for waist skinfold measures. These results support the possibility that differences in patterns of adiposity may contribute to familial risk of premenopausal breast cancer, and suggest the importance of conducting large scale, population-based studies of the link between body size characteristics and familial breast cancer risk.

Femoral-gluteal subcutaneous and intermuscular adipose tissues have independent and opposing relationships with CVD risk

Femoral-gluteal adipose tissue (AT) may be cardioprotective through fatty acids uptake. Femoral-gluteal AT has previously been defined as leg fat measured by dual energy x-ray absorptiometry (DXA); however, subcutaneous adipose tissue (SAT) and intermuscular adipose tissue (IMAT) are inseparable using DXA. This study investigated the independent relationships between femoral-gluteal SAT, femoral-gluteal IMAT, and cardiovascular disease (CVD) risk factors [fasting serum measures of glucose, total cholesterol (TC), high density lipoprotein cholesterol (HDLC), triglycerides (TG) and insulin] and whether race differences exist in femoral-gluteal AT distribution. Adult Caucasians (56 men and 104 women), African-Americans (37 men and 76 women), and Asians (11 men and 35 women) had total AT (TAT) including femoral-gluteal AT (upper leg SAT and IMAT) and visceral AT (VAT) by magnetic resonance imaging (MRI). General linear models identified the independent effects of femoral-gluteal SAT and femoral-gluteal IMAT on each risk factor after covarying for TAT, VAT, age, race, sex, and two-way interactions. Femoral-gluteal IMAT and glucose (P < 0.05) were positively associated independent of VAT. There were also significant inverse associations between femoral-gluteal SAT and insulin (P < 0.01) and TG (P < 0.05), although the addition of VAT rendered these effects nonsignificant, possibly due to collinearity. Asian women had less femoral-gluteal SAT and greater VAT than Caucasians and African-Americans (P < 0.05) and Asian and African-American men had greater femoral-gluteal IMAT than Caucasians, adjusted for age and TAT (P < 0.05 for both). Femoral-gluteal SAT and femoral-gluteal IMAT distribution varies by sex and race, and these two components have independent and opposing relationships with CVD risk factors.

Anatomical patterning of visceral adipose tissue: race, sex, and age variation

OBJECTIVE

We tested sex, race, and age differences in the patterning of visceral adipose tissue (VAT) and subcutaneous adipose tissue.

RESEARCH METHODS AND PROCEDURES

Contiguous 1-cm-thick magnetic resonance (MR) images of the abdomen were collected from 820 African-American and white adults. Repeated-measures ANOVA was used to examine the effects of image location, sex, race, and age (>or=50 vs. <50 years) on adipose tissue areas. Maximum VAT area was identified for each subject from the raw data.

RESULTS

Compared to women, men had greater total VAT volume (p < 0.0001), and their maximum VAT area occurred higher in the abdomen (p < 0.0001). Among white men, maximim VAT area most frequently occurred 5 to 10 cm above L4-L5, whereas in the other groups, maximim VAT area most frequently occurred 1 to 4 cm above L4-L5 (p < 0.0001). African-American men had greater total VAT volume than African-American women (p < 0.01), but this sex difference was only significant using single images cranial to L4-L5 + 2 cm. Age-related increases in VAT tended to be greatest 5 to 10 cm above L4-L5 in men and near L4-L5 in women.

DISCUSSION

A single MR image 5 to 10 cm above L4-L5 may allow more accurate conclusions than the L4-L5 image regarding group differences in visceral adiposity.

Quantitative comparison and evaluation of software packages for assessment of abdominal adipose tissue distribution by magnetic resonance imaging

OBJECTIVE

To examine five available software packages for the assessment of abdominal adipose tissue with magnetic resonance imaging, compare their features and assess the reliability of measurement results.

DESIGN

Feature evaluation and test-retest reliability of softwares (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision) used in manual, semi-automated or automated segmentation of abdominal adipose tissue.

SUBJECTS

A random sample of 15 obese adults with type 2 diabetes.

MEASUREMENTS

Axial T1-weighted spin echo images centered at vertebral bodies of L2-L3 were acquired at 1.5 T. Five software packages were evaluated (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision), comparing manual, semi-automated and automated segmentation approaches. Images were segmented into cross-sectional area (CSA), and the areas of visceral (VAT) and subcutaneous adipose tissue (SAT). Ease of learning and use and the design of the graphical user interface (GUI) were rated. Intra-observer accuracy and agreement between the software packages were calculated using intra-class correlation. Intra-class correlation coefficient was used to obtain test-retest reliability.

RESULTS

Three of the five evaluated programs offered a semi-automated technique to segment the images based on histogram values or a user-defined threshold. One software package allowed manual delineation only. One fully automated program demonstrated the drawbacks of uncritical automated processing. The semi-automated approaches reduced variability and measurement error, and improved reproducibility. There was no significant difference in the intra-observer agreement in SAT and CSA. The VAT measurements showed significantly lower test-retest reliability. There were some differences between the software packages in qualitative aspects, such as user friendliness.

CONCLUSION

Four out of five packages provided essentially the same results with respect to the inter- and intra-rater reproducibility. Our results using SliceOmatic, Analyze or NIHImage were comparable and could be used interchangeably. Newly developed fully automated approaches should be compared to one of the examined software packages.

Menopausal status and factors affecting cessation of menses in the region of Bonn, Germany

Because of the high prevalence of hormone use and reproductive surgeries in Western women natural menopause is a less frequent condition. Our aim was to examine the influences of hormonal and other factors on timing of cessation of menses. We analysed population controls of a German case-control study on breast cancer risks. The sample comprised N=829 women without hysterectomy or bilateral oophorectomy. We estimated the risk for the occurrence of last menses by Cox proportional hazard modelling. For calculating hazard rate ratios (HRR) and 95% confidence intervals (CI) women with menstrual cycles up to one year before interview were censored at that age. Median age at cessation of menses was 50 years (inter-quartile range 47–53 years). A significant later cessation of menses resulted from oral contraceptive use (HRR 0.74, 95% CI 0.59–0.93 for up to 10 years), and hormone therapy use until last menses (HRR 0.57, 95% CI 0.47–0.70). Also, thyroidal medications were associated with a delayed cessation of menses (HRR 0.64, 95% CI 0.42–0.96 for more than 10 years of use). Smoking until at least two years before last menses and allergies revealed an earlier cessation of bleedings (HRR 1.50, 95% CI 1.22–1.83 and HRR 1.28, 95% CI 1.07–1.53 respectively). Natural menopause is difficult to determine. Factors affecting the ovaries or the endocrine system can modulate timing of menopause. Endocrine biomarkers should be additionally taken into account when defining menopausal status.

Effect of a daily supplement of soy protein on body composition and insulin secretion in postmenopausal women

OBJECTIVE

To determine whether a supplement of soy protein improves body composition, body fat distribution, and glucose and insulin metabolism in postmenopausal women without diabetes compared with an isocaloric casein placebo.

DESIGN

Randomized, double-blind, placebo-controlled 3-month trial.

SETTING

Clinical Research Center.

PATIENT(S)

Fifteen postmenopausal women.

INTERVENTION(S)

Computed tomographic scans at L4/L5, dual energy x-ray absorptiometry, hyperglycemic clamps.

MAIN OUTCOME MEASURE(S)

Total fat, total abdominal fat, visceral fat, subcutaneous abdominal fat, and insulin secretion.

RESULT(S)

Weight by dual energy x-ray absorptiometry did not change between groups (+1.38 +/- 2.02 kg for placebo vs. +0.756 +/- 1.32 kg for soy, mean +/- SD). Total and subcutaneous abdominal fat increased more in the placebo group than in the soy group (for differences between groups in total abdominal fat: +38.62 +/- 22.84 cm(2) for placebo vs. -11.86 +/- 31.48 cm(2) for soy; subcutaneous abdominal fat: +22.91 +/- 28.58 cm(2) for placebo vs. -14.73 +/- 22.26 cm(2) for soy). Insulin secretion, visceral fat, total body fat, and lean mass did not differ between groups. Isoflavone levels increased more in the soy group.

CONCLUSION(S)

A daily supplement of soy protein prevents the increase in subcutaneous and total abdominal fat observed with an isocaloric casein placebo in postmenopausal women.

Changes in body composition in women over six years at midlife: ovarian and chronological aging

CONTEXT

Understanding the menopause association with body weight is important because excess weight increases risk for stroke, incident cardiovascular disease, cardiovascular mortality, and all-cause mortality among the middle-aged.

OBJECTIVE

The objective of this study was to examine chronological age and ovarian age and consider how these could influence body size and composition in midlife women.

DESIGN AND SETTING

The Study of Women's Health Across the Nation is a longitudinal, community-based study. This report uses data from the Michigan Study of Women's Health Across the Nation site.

PARTICIPANTS

Participants were 543 premenopausal or early perimenopausal African-American and Caucasian women aged 42-52 yr at baseline examination.

MAIN OUTCOME MEASURES

Waist circumference, fat mass and skeletal muscle mass, from bioelectrical impedance, were assessed in seven annual serial measures. Annual FSH values were assayed by ELISA. The final menstrual period was defined retrospectively after 12 months of amenorrhea.

RESULTS

There was an absolute cumulative 6-yr increase in fat mass of 3.4 kg and a 6-yr decrease in skeletal muscle mass of approximately 0.23 kg. There was an absolute cumulative 6-yr increase of approximately 5.7 cm in waist circumference. The (log)FSH change was positively correlated with (log)(fat mass) change. Waist circumference increased over the time period, but 1 yr after final menstrual period, the rate of increase slowed. Fat mass continued to increase with no change in rate.

CONCLUSIONS

Both time (chronological aging) and ovarian aging contributed to substantial changes in body composition (fat and skeletal muscle mass) and waist circumference. These changes have important ramifications for establishing a metabolic environment that can be healthy or unhealthy.

Insulin resistance with hormone replacement therapy: associations with markers of inflammation and adiposity

OBJECTIVE

This study was undertaken to determine whether insulin resistance associated with combination hormone replacement therapy (HRT) is mediated by changes in serum markers of inflammation or in serum adipocyte hormones.

STUDY DESIGN

Forty-five postmenopausal women, aged 55 +/- 7 years, were examined from a randomized, double-blind placebo-controlled trial evaluating the effect of HRT on insulin-stimulated glucose disposal and body composition. Volunteers were randomly assigned to conjugated estrogens 0.625 mg plus medroxyprogesterone acetate 2.5 mg vs placebo for 1 year. At baseline and at 1 year, body composition was assessed by dual photon x-ray absorptiometry scans; body fat distribution was measured by computed tomographic scans at the L4/L5 vertebral disk space; insulin sensitivity was measured by euglycemic hyperinsulinemic clamp; interleukin-6 (IL-6), leptin, and adiponectin were measured by enzyme-linked immunosorbent assay; and c-reactive protein (CRP) was measured by radioimmunoassay.

RESULTS

HRT increased CRP by 121% compared with a 32% increase with placebo (P = .03); HRT decreased glucose disposal by 17% compared with no change with placebo (P = .04) as reported previously. HRT did not affect body composition, body fat distribution, IL-6, leptin, or adiponectin. The increase in CRP did not correlate with the decrease in glucose disposal in the HRT group (R = 0.11, P = .65).

CONCLUSION

Treatment with HRT for one year increases CRP, but does not alter IL-6, adiponectin, or leptin. The change in CRP was not, however, related to the decrease in glucose disposal with HRT treatment.

Association of eating frequency with body fatness in pre- and postmenopausal women

OBJECTIVE

To examine associations between eating frequency (EF) and body fatness in pre- and postmenopausal women, after excluding potential low-energy reporters.

RESEARCH METHODS AND PROCEDURES

In this cross-sectional study of 220 free-living women, 64 pre- and 50 postmenopausal non-low-energy-reporting women were further analyzed (age, 24 to 74 years; BMI, 18.5 to 38.6 kg/m2). Anthropometric and body composition measurements (DXA) were performed in all study participants. EF, energy, and macronutrient intake were assessed by 3-day food record. Physical activity level and energy expenditure were assessed by self-reported questionnaire.

RESULTS

No association between EF and adiposity indices was detected in premenopausal women. In contrast, EF was positively correlated with percentage body fat in postmenopausal women (r = 0.30, p = 0.03). EF was positively correlated with total energy intake in both groups and with total energy expenditure in premenopausal women only (r = 0.34, p = 0.02). Multivariate analysis revealed that, in postmenopausal women, EF was a significant predictor of body fatness (standardized beta = 0.41, p = 0.01).

DISCUSSION

Frequent eating was not found to be related to adiposity in premenopausal women, but it was associated with increased body fat in postmenopausal women. Possible explanations could be that the frequent eating is not associated with a physically active lifestyle in postmenopausal women or that frequent eating predisposes women after menopause to a higher energy intake by increasing food stimuli and rendering it more difficult for them to control energy balance.

Sagittal abdominal diameter: no advantage compared with other anthropometric measures as a correlate of components of the metabolic syndrome in elderly from the Hoorn Study

BACKGROUND

The sagittal abdominal diameter has been proposed as a useful measure by which to estimate abdominal obesity and as being more strongly related to components of the metabolic syndrome than are other anthropometric measures.

OBJECTIVE

The objective was to study which anthropometric measure (ie, sagittal abdominal diameter, waist circumference, waist-to-hip ratio, waist-to-height ratio, or body mass index) is the strongest correlate of components of the metabolic syndrome (ie, glucose and lipid concentrations and blood pressure) in the elderly.

DESIGN

The Hoorn Study is a population-based cohort study in older Dutch men and women. Cross-sectional data were analyzed. Age-adjusted Pearson correlations of anthropometric measures with components of the metabolic syndrome were calculated in 826 subjects (389 men, 437 women) aged 56-83 y. Analyses were performed with adjustment for age and stratification for sex and age (<65 or >/=65 y).

RESULTS

No single anthropometric measure was consistently correlated more strongly with components of the metabolic syndrome than were the other measures in either men or women. The associations were generally stronger in younger subjects than in older subjects and in women than in men. For example, the correlation between sagittal abdominal diameter and postload glucose was 0.35 (P < 0.001) in younger and 0.14 (P = 0.051) in older men, and the correlation between waist circumference and postload glucose was 0.33 (P < 0.001) in older women and 0.14 (P = 0.062) in older men.

CONCLUSION

The use of sagittal abdominal diameter has no advantages over simpler and more commonly used anthropometric measures such as the waist circumference in older men and women.

Comment rester en forme(s) après 50 ans ?

It is common knowledge that when women reach the menopause, they put on weight and change body shape. The menopause is particularly feared as a sign of aging. The deficiency in estrogen at the menopause is responsible for the change from a gynoid fat pattern to an android one (i.e. fat accumulates on the upper portion of the abdomen instead of on the hips). In addition, women are no longer protected against CardioVascular Diseases (CVD), and will rapidly share the same risks as men. The menopause is marked by an increase in the prevalence of various CVD risk factors: elevated blood pressure, hypertriglyceridemia, Diabetes, etc. This phenomenon may be explained by an increase in the occurrence of the polymetabolic (PM) syndrome at this time of life. In the IDF ((International Diabetics Federation) 2005 definition, waist circumference becomes the main criterion of PM syndrome. Keeping a slim waist can no longer be considered a woman's vain obsession but a justified health concern, since the waist to height ratio is a better predictor of CVD than BMI (Body Mass Index). A diet and healthcare program is now available which, if followed from the age of 35, can help women live 'in good shape' and for longer.

Ovarian suppression with gonadotropin-releasing hormone agonist reduces whole body protein turnover in women

The age-related decline in fat-free mass is accelerated in women after menopause. The role of ovarian hormone deficiency in the regulation of fat-free mass, however, has not been clearly defined. To address this question, we examined the effect of ovarian hormone suppression on whole body protein metabolism. Whole body protein breakdown, oxidation, and synthesis were measured using [(13)C]leucine in young, healthy women with regular menstrual patterns before and after 2 mo of treatment with gonadotropin-releasing hormone agonist (GnRHa; n = 6) or placebo (n = 7). Protein metabolism was measured under postabsorptive and euglycemic-hyperinsulinemic-hyperaminoacidemic conditions. Ovarian suppression did not alter whole body or regional fat-free mass or adiposity. In the postabsorptive state, GnRHa administration was associated with reductions in protein breakdown and synthesis (P < 0.05), whereas no change in protein oxidation was noted. Under euglycemic-hyperinsulinemic-hyperaminoacidemic conditions, a similar reduction (P < 0.05) in protein synthesis and breakdown was noted, whereas, protein oxidation increased (P < 0.05) in the placebo group. Testosterone, steroid hormone precursors, insulin-like growth factor I, and their respective binding proteins were not altered by GnRHa administration, and changes in these hormones over time were not associated with GnRHa-induced alterations in protein metabolism, suggesting that changes in protein turnover are not due to an effect of ovarian suppression on other endocrine systems. Our findings provide evidence that endogenous ovarian hormones participate in the regulation of protein turnover in women.

Role of ovarian hormones in the regulation of protein metabolism in women: effects of menopausal status and hormone replacement therapy

The age-related decline in fat-free mass is accelerated in women after menopause, implying that ovarian hormone deficiency may have catabolic effects on lean tissue. Because fat-free tissue mass is largely determined by its protein content, alterations in ovarian hormones would likely exert regulatory control through effects on protein balance. To address the hypothesis that ovarian hormones regulate protein metabolism, we examined the effect of menopausal status and hormone replacement therapy (HRT) on protein turnover. Whole body protein breakdown, oxidation, and synthesis were measured under postabsorptive conditions using [(13)C]leucine in healthy premenopausal (n = 15, 49 +/- 1 yr) and postmenopausal (n = 18, 53 +/- 1 yr) women. In postmenopausal women, whole body protein turnover and plasma albumin synthesis rates (assessed using [(13)C]leucine and [(2)H]phenylalanine) were also measured following 2 mo of treatment with oral HRT (0.625 mg conjugated estrogens + 2.5 mg medroxyprogesterone acetate, n = 9) or placebo (n = 9). No differences in whole body protein breakdown, oxidation, or synthesis were found between premenopausal and postmenopausal women. Protein metabolism remained similar between groups after statistical adjustment for differences in adiposity and when subgroups of women matched for percent body fat were compared. In postmenopausal women, no effect of HRT was found on whole body protein breakdown, synthesis, or oxidation. In contrast, our results support a stimulatory effect of HRT on albumin fractional synthesis rate, although this did not translate into alterations in circulating albumin concentrations. In conclusion, our results suggest no detrimental effect of ovarian hormone deficiency coincident with the postmenopausal state, and no salutary effect of hormone repletion with HRT, on rates of whole body protein turnover, although oral HRT regimens may increase the synthesis rates of albumin.

17beta-estradiol is protective in spinal cord injury in post- and pre-menopausal rats

The neuroprotective effects of 17 beta -estradiol have been shown in models of central nervous system injury, including ischemia, brain injury, and more recently, spinal cord injury (SCI). Recent epidemiological trends suggest that SCIs in elderly women are increasing; however, the effects of menopause on estrogen-mediated neuroprotection are poorly understood. The objective of this study was to evaluate the effects of 17beta-estradiol and reproductive aging on motor function, neuronal death, and white matter sparing after SCI of post- and pre-menopausal rats. Two-month-old or 1- year-old female rats were ovariectomized and implanted with a silastic capsule containing 180 microg/mL of 17beta-estradiol or vehicle. Complete crush SCI at T8-9 was performed 1 week later. Additional animals of each age group were left ovary-intact but were spinal cord injured. The Basso, Beattie, Bresnahan (BBB) locomotor test was performed. Spinal cords were collected on post-SCI days 1, 7, and 21, and processed for histological markers. Administration of 17beta-estradiol to ovariectomized rats improved recovery of hind-limb locomotion, increased white matter sparing, and decreased apoptosis in both the post- and pre-menopausal rats. Also, ovary-intact 1-year-old rats did worse than ovary-intact 2-month-old rats, suggesting that endogenous estrogen confers neuroprotection in young rats, which is lost in older animals. Taken together, these data suggest that estrogen is neuroprotective in SCI and that the loss of endogenous estrogen-mediated neuroprotective seen in older rats can be attenuated with exogenous administration of 17beta-estradiol.

Predictors of worsening insulin sensitivity in postmenopausal women

OBJECTIVE

The purpose of this study was to determine predictors of worsening insulin sensitivity in postmenopausal women.

STUDY DESIGN

Seventy-one nonobese postmenopausal women were assigned randomly to receive hormone replacement therapy (conjugated estrogens, 0.625 mg, plus medroxyprogesterone acetate, 2.5 mg) or placebo daily for 1 year (34 women received hormone replacement therapy, and 37 women received placebo). At baseline and 12 months, the women received a computed tomography scan at the L4-L5 vertebral disk space, a dual x-ray absorptiometry scan, a euglycemic hyperinsulinemic clamp to measure insulin sensitivity, and a lipid profile. Declining insulin sensitivity was defined as the largest quartile change in insulin sensitivity in the women who received the placebo (-1.42 mg/min/kg lean body mass).

RESULTS

By univariate analysis, we found that significant predictors of worsening insulin sensitivity were the use of hormone replacement therapy, baseline insulin sensitivity, a younger age, and <10 years since menopause. By logistic regression, we determined that hormone replacement therapy use and higher baseline insulin sensitivity were independent predictors of worsening insulin sensitivity.

CONCLUSION

The use of hormone replacement therapy and baseline insulin sensitivity are significant independent predictors of the development of worsening insulin sensitivity in postmenopausal women.

Soy isoflavones, body composition, and physical performance

OBJECTIVES

Physiologic changes, occurring during the process of aging, can have serious health consequences, such as increased risk of chronic disease and disability. Decline in estradiol levels after menopause is hypothesized to contribute to this risk. Thus, hormone therapy (HT) might prevent or delay those changes. However, HT has serious side effects and alternative approaches are needed.

METHODS

We performed a 12-month double-blind randomized trial comparing soy protein containing 99mg isoflavones (aglycone weights) with milk protein (placebo) daily in 202 postmenopausal women aged 60-75 years. Endpoints were body composition, and physical performance. Randomization resulted in reasonable well-balanced groups, 153 (76%) women completed the trial. Compliance was good (plasma genistein levels 55 +/- 101 and 1259 +/- 1610 nmol/L for placebo and soy group, respectively). The changes in the endpoints during the intervention period among the two intervention groups were analyzed.

RESULTS

Body mass index (BMI) and waist-to-hip ratio did not change during intervention. Handgrip strength at the final visit was slightly worse in the soy group compared to the placebo group (-0.45 kg (95% C.I.: -2.5, 1.6 kg; p = 0.7), but this difference was not statistically significant. Self-reported functional status, mobility and physical performance, all slightly improved during intervention but there were no differences between the groups.

CONCLUSIONS

The results of the present trial do not support the view that soy isoflavones have favorable effects on body composition and physical performance in postmenopausal women.

Relationship of body fat distribution by waist circumference, dual-energy X-ray absorptiometry and ultrasonography to insulin resistance by homeostasis model assessment and lipid profile in obese and non-obese postmenopausal women

OBJECTIVE

To correlate body fat distribution evaluated by waist circumference, dual-energy X-ray absorptiometry and ultrasonography to insulin resistance and lipid profile in obese and non-obese postmenopausal women.

METHODS

We studied 40 obese and 47 non-obese postmenopausal women, assessing obesity by measuring waist circumference and fat tissue using dual-energy X-ray absorptiometry and ultrasonography, and examining their correlation with metabolic parameters: insulin resistance as determined by the homeostasis model assessment technique (HOMA-IR) and lipid profile including triglycerides (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), very-low-density lipoprotein, lipoprotein(a) (Lp(a)) and apoplipoprotein A-I (Apo A-I).

RESULTS

There was no difference in lipid profile between the two groups. Insulin resistance was the metabolic disturbance of highest prevalence in the obese group, evaluated by HOMA-IR (obese: 3.38 +/- 2.2; non-obese: 1.20 +/- 0.7; p < 0.001). Obesity was not a confounding factor in linear regression analyses among HOMA-IR, HDL-C, TG, Lp(a), Apo A-I and the methods used to measure body fat distribution. Waist circumference was the method that best explained HOMA-IR (R(2) = 34.9%, p < 0.001) and TG concentration (R(2) = 10.9%, p = 0.002). HDL-C presented a positive association with subcutaneous fat evaluated by ultrasonography (R(2) = 12.5%, p < 0.001). Obesity was a confounding factor in multiple regression analyses between TC and LDL-C, when related to abdominal fat evaluated by ultrasonography, and resulted in a positive association among the obese and a negative association among the non-obese women. The sensibility of this method was related to the quantity of fat in the visceral region.

CONCLUSIONS

Waist circumference showed the highest association with insulin resistance. Fat distribution evaluated by dual-energy X-ray absorptiometry and ultrasound was also associated with insulin resistance, but with lower intensity. The relationship of visceral fat distribution evaluated by ultrasound to TC cholesterol and LDL-C showed opposed results between obese and non-obese menopausal women.

The effect of hormone replacement therapy and/or exercise on skeletal muscle attenuation in postmenopausal women: a yearlong intervention

Hormone replacement therapy (HRT) has been reported to exert a positive effect on preserving muscle strength following the menopause, however, the mechanism of action remains unclear. We examined whether the mechanism involved preservation of muscle composition as determined by skeletal muscle attenuation. Eighty women aged 50-57 years were randomly assigned to either: HRT, exercise (Ex), HRT+exercise (ExHRT), and control (Co) for 1 year. The study was double-blinded with subjects receiving oestradiol and norethisterone acetate (Kliogest) or placebo. Exercise included progressive high-impact training for the lower limbs. Skeletal muscle attenuation in Hounsfield units (HU) was determined by computed tomography of the mid-thigh. Areas examined were the quadriceps compartment (includes intermuscular adipose tissue), quadriceps muscles, the posterior compartment and posterior muscles. Muscle performance was determined by knee extensor strength, vertical jump height, and running speed over 20 m. Fifty-one women completed the intervention. Vertical jump height and running speed improved in the HRT and ExHRT groups compared with Co (interaction, P<0.01). For both the quadriceps compartment and quadriceps muscles, HU significantly increased (interaction, P<or=0.005) for HRT, Ex, and ExHRT compared with Co. For the posterior compartment, HU for the HRT and ExHRT were significantly increased compared with Co, while for posterior muscles, ExHRT was significantly greater than Co. Although the effects were modest, the results indicate that HRT, either alone or combined with exercise, may play a role in preserving/improving skeletal muscle attenuation in early postmenopausal women and thereby exert a positive effect on muscle performance.

Menopause, Physical Activity, and Body Composition/Fat Distribution in Midlife Women

PURPOSE

Hormonal changes associated with menopause, chronological aging, and lifestyle, specifically physical activity, may all influence the changes in body composition and fat distribution experienced by midlife women. This cross-sectional study examined those relations in a representative sample of 248 white and Chinese women, ages 47-57, participating in an ancillary study to the Study of Women's Health Across the Nation (SWAN), a multi-center, longitudinal investigation of the natural history of the menopause in a racially/ethnically diverse cohort.

METHODS

Body composition (lean mass, percent body fat) was assessed with dual energy x-ray absorptiometry, and central adiposity was determined by waist circumference. Physical activity was assessed from 7 d of accelerometer recordings. Menopausal status was based on self-reported bleeding patterns.

RESULTS

Higher levels of physical activity, particularly vigorous-intensity activity, were generally independently associated with decreased percent body fat and smaller waist circumference, although these findings were not statistically significant in the Chinese women. Among the white women, every half a standard deviation increase in total activity was associated with a 1.6-point decrease in percent body fat (P = 0.002). Waist circumference decreased from 96.2 cm (SE = 1.04) in those doing no vigorous-intensity activity to 81.4 cm (SE = 1.05) in those doing 10 min or more a day (P for trend = 0.05). For both the whites and the Chinese, late peri- and postmenopausal status was associated with lower lean mass, and among the Chinese, tended to be associated with higher percent body fat.

CONCLUSION

These findings suggest that regular physical activity may help to mitigate the tendency for weight gain and adverse changes in body composition and fat distribution that accompany aging and the menopausal transition.

Cardiovascular risk at age 53 years in relation to the menopause transition and use of hormone replacement therapy: a prospective British birth cohort study

OBJECTIVES

To investigate cardiovascular risk factors and changes in risk factor levels in relation to menopausal stage, hysterectomy status and hormone replacement therapy use in a cohort of women aged 53 years with prospective data on smoking, lifetime socio-economic circumstances, and blood pressure and obesity at age 43 years.

DESIGN

A prospective study.

SETTING

England, Scotland and Wales.

POPULATION

A cohort of women from the Medical Research Council Survey of Health and Development.

METHODS

A total of 1303 women, aged 53 years, from a UK birth cohort study with measures of cardiovascular risk factors were classified by five menopausal status groups (premenopause, perimenopause, postmenopause, hysterectomy and hormone replacement therapy user). Body mass index, glycosolated haemoglobin, blood pressure, high density lipoprotein, low density lipoprotein and total cholesterol measurements were taken, and analysed within the groups taking confounding variables into account. Changes in body mass index and blood pressure measurement in the same women obtained when 43 years of age were also compared.

MAIN OUTCOME MEASURES

Body mass index, glycosolated haemoglobin, blood pressure, high density lipoprotein, low density lipoprotein and total cholesterol.

RESULTS

At 53 years, body mass index, waist circumference, total and low density lipoprotein cholesterol, and glycosolated haemoglobin (HbA1c) varied by menopausal status group, but blood pressure did not. Levels of total cholesterol and HbA1c increased across the natural menopause transition, before and after adjustment for body mass index, smoking and lifetime socio-economic circumstances. After adjustment for confounders, levels of risk factors for hysterectomised women were similar to those of naturally postmenopausal women. Women on hormone replacement therapy had lower levels of total and low density lipoprotein cholesterol, HbA1c, and were less obese than postmenopausal women. The lower obesity levels were partly due to these women already being less obese at age 43 years.

CONCLUSIONS

This study showed that naturally postmenopausal or hysterectomised women had higher levels of metabolic risk factors compared with premenopausal or perimenopausal women of the same age. The long term stability of these differences and their translation into variations in incidence of cardiovascular disease remain to be seen. The lower levels of metabolic risk factors for women on hormone replacement therapy may protect against future cardiovascular disease or may be overwhelmed by other adverse, and as yet unknown, effects of hormone replacement therapy.