Body fatness and breast cancer risk in relation to phosphorylated mTOR expression in a sample of predominately Black women.

BACKGROUND: The mechanistic target of rapamycin (mTOR) pathway promoted by positive energy imbalance and insulin-like growth factors can be a mechanism by which obesity influences breast cancer risk. We evaluated the associations of body fatness with the risk of breast cancer varied with phosphorylated (p)-mTOR protein expression, an indication of the pathway activation. METHODS: Women with newly diagnosed breast cancer (n = 715; 574 [80%] Black and 141 [20%] White) and non-cancer controls (n = 1983; 1280 [64%] Black and 713 [36%] White) were selected from the Women's Circle of Health Study. Surgical tumor samples among the cases were immunostained for p-mTOR (Ser2448) and classified as p-mTOR-overexpressed, if the expression level ≥ 75th percentile, or p-mTOR-negative/low otherwise. Anthropometrics were measured by trained staff, and body composition was determined by bioelectrical impedance analysis. Odds ratios (ORs) of p-mTOR-overexpressed tumors and p-mTOR-negative/low tumors compared to controls were estimated using polytomous logistic regression. The differences in the associations by the p-mTOR expression status were assessed by tests for heterogeneity. RESULTS: Cases with p-mTOR-overexpressed tumors, but not cases with p-mTOR-negative/low tumors, compared to controls were more likely to have higher body mass index (BMI), percent body fat, and fat mass index (P-heterogeneity < 0.05), although the OR estimates were not significant. For the measurement of central adiposity, cases with p-mTOR overexpressed tumors had a higher odds of being at the Q3 (OR = 2.52, 95% CI = 1.46 to 4.34) and Q4 (OR = 1.99, 95% CI = 1.12 to 3.50) of waist circumference (WC) compared to controls. Similarly, cases with p-mTOR overexpressed tumors had a higher odds of being at the Q3 (OR = 1.82, 95% CI = 1.11 to 2.98) and Q4 (OR = 1.81, 95% CI = 1.11 to 2.98) of WHR compared to controls. These associations of WC and waist-to-hip ratio (WHR) did not differ by tumor p-mTOR status (P-heterogeneity = 0.27 and 0.48, respectively). CONCLUSIONS: Our findings suggest that in this population composed of predominately Black women, body fatness is associated with breast cancer differently for p-mTOR overexpression and p-mTOR negative/low expression. Whether mTOR plays a role in the obesity and breast cancer association warrants confirmation by prospective studies.

Distortion and dissatisfaction with body size per the demographic and academic characteristics and the nutritional status of university students

To identify the prevalence of distortion and dissatisfaction with the body size of Brazilian university students, and establish their relationship with the demographic and academic characteristics and the anthropometric nutritional status. The sample consisted of students from a public university in the state of São Paulo. The Figure Rating Scale (FRS) for Brazilian adults was used as an instrument. The participants selected the figure that corresponded to the current body and another one for the desired body. The prevalence of distortion and dissatisfaction with body sizewas calculated with 95% confidence interval (95% CI). The association between the variables was evaluated by the Chi-Square Test (χ2). The significance level of 5% was adopted. A total of 356 students (women=71.63%) with a mean age of 20.95 (SD=2.55) years participated. The prevalence of distortion and dissatisfaction with body size was 73.03% (95% CI=68.23­77.83) and 79.49% (95% CI=75.3­83.68), respectively. There was a high prevalence of distortion with body size among individuals with low weight (χ2=9.523, p=0.009). Students who distorted the body size (52.31% [95% CI=47.12­57.50]) underestimated their body size. The type of distortion was related to sex (χ2=26.35, p<0.001), physical activity (χ2=4.51, p=0.034), use of supplements (χ2=4.62, p=0.032), andthe anthropometric nutritional status (χ2=9.05, p=0.011). Students dissatisfied with the body (58.66% [95% CI=52.92­64.40]) wished to reduce the body size. The type of dissatisfaction was related to sex (χ2=5.79, p=0.016) and anthropometric nutritional status (χ2=89.83, p<0.001). The prevalence of body size underestimation was higher among men, students who practice physical activity, subjects using dietary supplements and underweight individuals. The wish to decrease body size was higher among women and overweight/obese individuals.(AU)

ABSI is a poor predictor of insulin resistance in Chinese adults and elderly without diabetes.

OBJECTIVE: Recently, a new obesity index (A Body Shape Index, ABSI) based on waist circumference (WC) was developed, and high ABSI corresponds to a more central concentration of body volume. It is well known that central obesity is closely linked with insulin resistance (IR). Therefore, our study aimed to examine the discriminatory power of ABSI for IR in Chinese adults and elderly without diabetes. SUBJECTS AND METHODS: In 2007, a cross-sectional study was made. In this study, 570 individuals without diabetes were available for analysis (male: 56.1%, mean age: 62.3 ± 6.5 years). Insulin resistance was assessed by homeostasis model assessment (HOMA-IR). Areas under the receiver operating characteristic (ROC) curves were determined to identify variables/models that could predict insulin resistance. RESULTS: ABSI was associated with IR, the cut-off points was 0.0785 m11/6kg-2/3 to identifying IR and the area under the ROC (AUC) curve was 0.618 (95%CI: 0.561-0.675), which was not better than body mass index BMI (AUC = 0.753; 95%CI: 0.706-0.801), WC (AUC = 0.749; 95%CI: 0.700-0.797), and fasting plasma glucose (FPG, AUC = 0.752; 95%CI: 0.705-0.799). Furthermore, combination with ABSI could improve the discriminatory power of other variables for IR. The AUC curve increased from 0.753 to 0.771for BMI, 0.749 to 0.754 for WC, 0.752 to 0.769 for FPG, respectively. CONCLUSIONS: ABSI is associated with IR in the general Chinese adults and elderly without diabetes, but the discriminatory power for IR is poor. It is recommended that ABSI be used in combination with other variables.

ABSI is a poor predictor of insulin resistance in Chinese adults and elderly without diabetes

ABSTRACT Objective: Recently, a new obesity index (A Body Shape Index, ABSI) based on waist circumference (WC) was developed, and high ABSI corresponds to a more central concentration of body volume. It is well known that central obesity is closely linked with insulin resistance (IR). Therefore, our study aimed to examine the discriminatory power of ABSI for IR in Chinese adults and elderly without diabetes. Subjects and methods: In 2007, a cross-sectional study was made. In this study, 570 individuals without diabetes were available for analysis (male: 56.1%, mean age: 62.3 ± 6.5 years). Insulin resistance was assessed by homeostasis model assessment (HOMA-IR). Areas under the receiver operating characteristic (ROC) curves were determined to identify variables/models that could predict insulin resistance. Results: ABSI was associated with IR, the cut-off points was 0.0785 m11/6kg-2/3 to identifying IR and the area under the ROC (AUC) curve was 0.618 (95%CI: 0.561-0.675), which was not better than body mass index BMI (AUC = 0.753; 95%CI: 0.706-0.801), WC (AUC = 0.749; 95%CI: 0.700-0.797), and fasting plasma glucose (FPG, AUC = 0.752; 95%CI: 0.705-0.799). Furthermore, combination with ABSI could improve the discriminatory power of other variables for IR. The AUC curve increased from 0.753 to 0.771for BMI, 0.749 to 0.754 for WC, 0.752 to 0.769 for FPG, respectively. Conclusions: ABSI is associated with IR in the general Chinese adults and elderly without diabetes, but the discriminatory power for IR is poor. It is recommended that ABSI be used in combination with other variables.

Mississippian subadults from the Middle Cumberland and Eastern regions of Tennessee: Biological indicators of population interaction.

OBJECTIVES: Human subadult skeletal remains can provide a unique perspective into biosocial aspects of Mississippian period population interactions within and between the Middle Cumberland (MCR) and Eastern Tennessee Regions (ETR). The majority of previous studies have concentrated on adult skeletal remains, leaving out a large and extremely important population segment. METHODS: Skeletal indicators of disease, growth, body proportions, and metabolic stress were collected from subadult remains from five archaeological sites over several temporal periods. Crucial to overcoming limitations associated with the osteological paradox, the biological results were placed into an archaeological context based on prior studies as well as paleoclimatological data. RESULTS: Results reveal homogeneity both within and between regions for most skeletal indicators. However, MCR individuals exhibit a higher frequency of pathology than those from ETC, while stature is significantly lower in younger subadults from the MCR. Within the ETR, there is no evidence for biological differences between Early Dallas and subsequent Late Dallas and Mouse Creek cultural phases. Despite presumed signs of increased conflict at the Dallas site, frequencies and types of skeletal pathology and growth disruptions are comparable to other regional sites. CONCLUSIONS: These findings suggest that despite cultural differences between the ETR and MCR, there was no large-scale intrusion from an outside population into the ETR during the Late Mississippian Period, or if one occurred, it is biologically invisible. Combined with climatic and archaeobotanical data, results suggest the MCR subadults were under increased stress in their earlier years. This may have been associated with increased interpersonal violence and dependence on few food sources occurring with greater scarcity.

Reference centile curves for wrist circumference for Indian children aged 3-18 years.

BACKGROUND: Childhood obesity and its consequences have reached alarming proportions worldwide and in India. Wrist circumference is emerging as an easily measurable reproducible parameter for screening children at risk of obesity-related morbidities such as hypertension and insulin resistance. The objectives of this study were: (1) to compute age and gender-specific wrist circumference percentiles for 3-18-year-old apparently healthy Indian children and adolescents; (2) to assess the relationship of wrist circumference with measures of obesity and adiposity such as body mass index (BMI), fat percentage and blood pressure (BP) and (3) to suggest age and gender-specific cut-offs for wrist circumference percentile for the risk of hypertension in Indian children and adolescents. METHODS: This was a cross-sectional study on samples of 10,199 3-18-year-old children (5703 boys) from randomly selected schools from five major cities in India. Height, weight, waist and wrist circumference and BP were recorded. Body composition was measured using bioelectrical impedance analysis (BIA). Wrist circumference percentiles were computed using the LMS method. RESULTS: The average wrist circumference of boys and girls was 10.4 cm and 10.0 cm at 3 years and increased to 15.1 cm and 13.9 cm, respectively, at 18 years. Compared to their Caucasian counterparts, Indian children's wrists were smaller. Receiver operating characteristic (ROC) curve analysis derived the 70th percentile of wrist circumference as the cut-off for identifying the risk of hypertension. CONCLUSIONS: Contemporary cross-sectional reference percentile curves for wrist circumference for 3-18-year-old Indian children are presented. The 70th percentile of the current study is proposed as the cut-off to screen children for cardiometabolic risk factors such as hypertension.

Perceived ideal body size of Ghanaian women: "Not too skinny, but not too fat".

Body size issues are gaining public health attention because of the fast rising epidemic of overweight and obesity across the globe. This study explored Ghanaian women's subjective perceptions regarding ideal body size for women. A purposive sampling strategy was employed in recruiting 36 women across the body weight spectrum from Tamale (n = 17) and Accra (n = 19) in Ghana. Qualitative data were obtained from in-depth interviews using a semi-structured interview guide. Data from the interviews were analyzed deductively. The mean body mass index of participants was 33.5 ± 10 kg/m2: sixteen of the participants were obese, eight were overweight, eleven were normal weight, and one was underweight. The participants almost unanimously had a preference for an ideal body size slightly above the normal, but not necessarily obese. Typically described as "not too skinny, but not too fat," this preferred ideal reflected a fuller, curvier, and shapelier body, as opposed to the Western ideal of thinner body type. Women often felt pressured by peers and family members to have a slightly heavier body size. Health education efforts are needed to focus on messages that seek to challenge existing body size perceptions that may inhibit women's willingness to maintain a healthy body weight.

Prognostic Impact of Low-Flow Severe Aortic Stenosis in Small-Body Patients Undergoing TAVR: The OCEAN-TAVI Registry.

OBJECTIVES: This study aimed to analyze the prognostic impact of low-flow (LF) severe aortic stenosis in small-body patients undergoing transcatheter aortic valve replacement (TAVR). BACKGROUND: Western literature demonstrates a poor prognosis with paradoxical LF and low-flow low-gradient (LF-LG) severe aortic stenosis (AS), as defined by stroke volume index (SVi) <35 ml/m2 and mean pressure gradient <40 mm Hg with preserved left ventricular ejection fraction (LVEF). However, this poor prognosis is contested in Japan owing to the smaller body size of Japanese patients relative to that of Western patients. Additionally, there are no reports of the prognostic implication of paradoxical LF or LF-LG severe AS in small-body patients undergoing TAVR. METHODS: This was a retrospective analysis of 723 consecutive Japanese patients (median age 85 years; 32.6% male; median body surface area 1.4 m2) who underwent TAVR for severe AS at 9 sites in Japan. The primary and secondary endpoints were cumulative all-cause and cardiovascular mortality after TAVR, respectively. RESULTS: Ninety-seven (13.4%) patients had paradoxical LF severe AS whereas 38 (5.3%) had paradoxical LF-LG with severe AS. PLF was associated with a significant increase in all-cause (hazard ratio [HR]: 3.00; 95% confidence interval [CI]: 1.34 to 6.72; p < 0.001) and cardiovascular mortality (HR: 5.58; 95% CI: 1.19 to 26.2; p < 0.01), as compared with patients' normal flow and preserved LVEF. PLF-LG was associated with a significant increase in all-cause mortality (HR: 3.76; 95% CI: 1.09 to 13.73; p < 0.01), as compared with normal flow high gradient with preserved LVEF. SVi was an independent predictor of cardiovascular mortality on multivariate analysis after adjustments for age, sex, clinically relevant variables, and other echocardiographic parameters (HR: 1.96; 95% CI: 1.19 to 3.23; p < 0.01). CONCLUSIONS: Among Japanese small-body patients with severe AS, both paradoxical LF and LF-LG severe AS were associated with poor outcomes following TAVR. SVi was an independent predictor of cardiovascular mortality after TAVR. (Optimised Transcatheter Valvular Intervention registry [OCEAN-TAVI]; UMIN000020423).

Comparison of Mid-Upper Arm Circumference and Weight-for-Height to Diagnose Severe Acute Malnutrition: A Study in Southern Ethiopia.

Weight-for-height Z-score (WHZ) and mid-upper arm circumference (MUAC) are two independent anthropometric indicators for diagnosing and admitting children with severe acute malnutrition (SAM) for treatment. While severely wasted children are at high risk of mortality, MUAC and WHZ do not always identify the same population of children as having SAM. Understanding how this discrepancy relates to age and sex may provide valuable information for care programmes for children with SAM. Age and sex distribution for differences between children identified as SAM by MUAC and WHZ were examined and the degree of agreement calculated. Children (n = 4297) aged 6-59 months with validated anthropometric measures were recruited from a population-based survey conducted in rural southern Ethiopia. MUAC < 115 mm and WHZ < -3 were used to define severe wasting as per the World Health Organization (WHO) classification. The kappa coefficient (κ) was calculated. There was fair agreement between the MUAC and WHZ definitions of severe wasting in boys (κ = 0.37) and children younger than 24 months (κ = 0.32) but poor agreement in girls (κ = 0.15) and children aged 24 months and above (κ = 0.13). More research is needed on response to treatment and prediction of mortality using different anthropometric measurements in relation to ages and sex of children.

Emergency weight estimation lookup tables for New Zealand children aged 5-10 years.

OBJECTIVE: To derive novel emergency weight estimation tables for New Zealand children aged 5-10 years using ethnicity and sex to increase accuracy and precision. METHODS: Using an existing dataset (collected in five New Zealand primary schools during July 2013; n = 376), body mass index and current emergency weight estimates were calculated. Stepwise regression with Akanke Information produced two best-fit models for predicting weight, one based on age and the other on height. Potential explanatory variables included ethnicity, sex and body habitus. RESULTS: The length-based model included height, ethnicity and body habitus. Accuracy (weight estimates within 10% of actual weight) for the length-based lookup table (74.8%) was similar to that for the Broselow-Luten tape (73.4%). The age-based model included age, sex, ethnicity and body habitus. Accuracy (51.3%) for the age-based lookup table was better than for existing formulae including Shann (45.7%), Advanced Paediatric Life Support (39.1%) and Theron (28.7%). CONCLUSION: The most accurate method for weight estimation in Auckland children aged 5-10 years is either the novel length-based lookup table or the existing Broselow-Luten tape. When length-based methods are not possible, the age-based lookup tables incorporating age, sex, ethnicity and body habitus are more accurate than existing methods of weight estimation.

"Permission to Speak": A Postcolonial View on Racialized Bodies and PE in the Current Context of Globalization.

The current neoliberal context of schools presents difficult challenges in addressing persistent issues of social inequalities. In this article, first, I argue that because of today's market-driven education, the rise of fitness testing in school physical education (PE) can be seriously detrimental to young people in general and to ethnic-minority young people's embodied identity in particular. Second, I explain how the racialization process circulated by the body-at-risk discourse, sustained by the media, and reproduced by high-stakes testing in PE forces ethnic-minority young people to construct their identities through White eyes, which alienates them from a consciousness of their own identity. Third, I explore the possible uses and pitfalls of Spivak's theoretical notion of "strategic essentialism" to put forward strategies to build a positive image of the "other" while attempting to avoid the erasure of difference. Fourth, I conclude the article by suggesting how Spivak's notion of strategic essentialism can be useful in rethinking current PE fitness practices.

Anthropometric characteristics of female smallholder farmers of Uganda--Toward design of labor-saving tools.

Sub-Saharan African women on small-acreage farms carry a disproportionately higher labor burden, which is one of the main reasons they are unable to produce for both home and the market and realize higher incomes. Labor-saving interventions such as hand-tools are needed to save time and/or increase productivity in, for example, land preparation for crop and animal agriculture, post-harvest processing, and meeting daily energy and water needs. Development of such tools requires comprehensive and content-specific anthropometric data or body dimensions and existing databases based on Western women may be less relevant. We conducted measurements on 89 women to provide preliminary results toward answering two questions. First, how well existing databases are applicable in the design of hand-tools for sub-Saharan African women. Second, how universal body dimension predictive models are among ethnic groups. Our results show that, body dimensions between Bantu and Nilotic ethnolinguistic groups are different and both are different from American women. These results strongly support the need for establishing anthropometric databases for sub-Saharan African women, toward hand-tool design.

Birth weight, early life course BMI, and body size change: Chains of risk to adult inflammation?

This paper examines how body size changes over the early life course to predict high sensitivity C-reactive protein in a U.S. based sample. Using three waves of the National Longitudinal Study of Adolescent Health (Add Health), we test the chronic disease epidemiological models of fetal origins, sensitive periods, and chains of risk from birth into adulthood. Few studies link birth weight and changes in obesity status over adolescence and early adulthood to adult obesity and inflammation. Consistent with fetal origins and sensitive periods hypotheses, body size and obesity status at each developmental period, along with increasing body size between periods, are highly correlated with adult CRP. However, the predictive power of earlier life course periods is mediated by body size and body size change at later periods in a pattern consistent with the chains of risk model. Adult increases in obesity had effect sizes of nearly 0.3 sd, and effect sizes from overweight to the largest obesity categories were between 0.3 and 1 sd. There was also evidence that risk can be offset by weight loss, which suggests that interventions can reduce inflammation and cardiovascular risk, that females are more sensitive to body size changes, and that body size trajectories over the early life course account for African American- and Hispanic-white disparities in adult inflammation.

Growth pattern from birth to adulthood in African pygmies of known age.

The African pygmy phenotype stems from genetic foundations and is considered to be the product of a disturbance in the growth hormone-insulin-like growth factor (GH-IGF) axis. However, when and how the pygmy phenotype is acquired during growth remains unknown. Here we describe growth patterns in Baka pygmies based on two longitudinal studies of individuals of known age, from the time of birth to the age of 25 years. Body size at birth among the Baka is within standard limits, but their growth rate slows significantly during the first two years of life. It then more or less follows the standard pattern, with a growth spurt at adolescence. Their life history variables do not allow the Baka to be distinguished from other populations. Therefore, the pygmy phenotype in the Baka is the result of a change in growth that occurs during infancy, which differentiates them from East African pygmies revealing convergent evolution.

Ethnic differences in fetal size and growth in a multi-ethnic population.

OBJECTIVES: Impaired or excessive fetal growth is associated with adverse short- and long-term health outcomes that differ between ethnic groups. We explored ethnic differences in fetal size and growth from mid pregnancy until birth. METHODS: Data are from the multi-ethnic STORK-Groruddalen study, a population-based, prospective cohort of 823 pregnant women and their offspring in Oslo, Norway. Measures were z-scores of estimated fetal weight (EFW), head circumference (HC), abdominal circumference (AC) and femur length (FL), in gestational week 24, 32 and 37, measured by ultrasound, and similar measures at birth. Differences in fetal size and growth were assessed using separate Linear Mixed Models including all four time points, with ethnic Europeans as reference. RESULTS: In week 24 South Asian fetuses had smaller AC, but larger FL than Europeans, and slightly lower EFW (-0.17 SD (-0.33, -0.01), p=0.04). Middle East/North African fetuses also had larger FL, but similar AC, and hence slightly higher EFW (0.18 (0.003, 0.36), p=0.05). Both groups had slower growth of AC, FL and EFW from this time until birth, and had -0.61 SD (-0.73, -0.49) and -0.28 SD (-0.41, -0.15) lower birth weight respectively. Ethnic East Asians, on the other hand, were smaller throughout pregnancy and had -0.58 SD (-0.82, -0.34) lower birth weight. Significant ethnic differences remained after adjusting for maternal factors. CONCLUSION: We observed ethnic differences in fetal size and body proportions already in gestational week 24, and in fetal growth from this time until birth, which were only partly explained by key maternal factors.

How Does Bone Strength Compare Across Sex, Site, and Ethnicity?

BACKGROUND: The risk of fragility fractures in the United States is approximately 2.5 times greater among black and white women compared with their male counterparts. On average, men of both ethnicities have wider bones of greater cortical mass compared with the narrower bones of lower cortical mass among women. However, it remains uncertain whether the low cortical area observed in the long bones of women is consistent with their narrower bone diameter or if their cortical area is reduced beyond that which is expected for the sex differences in body size and external bone size. QUESTIONS/PURPOSES: We asked (1) do black and white women consistently have narrower bones of less strength across long bones compared with black and white men; and (2) do all long bones of black and white women have reduced cortical area compared with black and white men? METHODS: Peripheral quantitative CT was used to quantify bone strength and cross-sectional morphology from the major long bones of 125 white and 115 black adult men and women (20-35 years of age). Regression analyses were used to test for differences in bone strength and cortical area after for adjusting for either body size, bone size, or both. RESULTS: After adjusting bone strength for body size, regression analyses showed that black women had lower bone strength compared with black men (women: mean=298.7-25,522 mg HA mm4, 95% confidence interval [CI], 270-27,692 mg HA mm4; men: mean = 381.6-30,945 mg HA mm4, 95% CI, 358.2-32,853 mg HA mm4; percent difference=12%-38%, p=0.06-0.0001). Similarly, white women also had lower bone strength compared with white men (women: mean=229.5-22,892 mg HA mm4, 95% CI, 209.3-24,539 mg HA mm4; men: mean=314.3-29,986 mg HA mm4, 95% CI, 297.3-31,331 mg HA mm4; percent difference=27%-49%, p=0.0001). All long bones of women for both ethnicities showed lower cortical area compared with men. After accounting for both body size and external bone size, black women (women: mean=43.25-357.70 mm2, 95% CI, 41.45-367.52 mm2; men: mean=48.06-400.10 mm2, 95% CI, 46.67-408.72; percent difference=6%-25%, p=0.02-0.0001) and white women (women: mean=38.53-350.10 mm2, 95% CI, 36.99-359.80 mm2; men: mean=42.06-394.30 mm2, 95% CI, 40.95-402.10 mm2; percent difference=6%-22%, p=0.02-0.0001) were shown to have lower cortical area than their male counterparts. Therefore, the long bones of women are not only more slender than those of men, but also show a reduced cortical area that is 6% to 25% greater than expected for their external size, depending on the bone being considered. CONCLUSIONS: The long bones of females are not just a more slender version of male long bones. Women have less cortical area than expected for their body size and bone size, which in part explains their reduced bone strength when compared with the more robust bones of men. CLINICAL RELEVANCE: The outcome of this assessment may be clinically important for the development of diagnostics and treatment regimens used to combat fractures. Future work should look at how the relationship among parameters reported here translates to the more fracture-prone metaphyseal regions.

Secular trends in average height and age at menarche of ethnic Russians and Komi-Permyaks of the Permsky Krai, Russia.

The aim was to describe the changes in body size and age at menarche in anthropologically distinct ethnic groups - Komi-Permyaks (KP) and Russians (RU) - of Permsky Krai that occurred in the last century, with a special concern to the urban-rural differences. The comparison of the 1861 - 1865 and 1990 birth cohorts (BiCo) revealed following results. In RU rural males the increase in stature (ST) was 10.8 cm (p < 0.001). The chest circumference has increased by 5.9 cm, but it is unsubstantial 0.25 % when measured in relative to ST values. In RU urban males the overall increase in ST was 10.8 cm (p < 0.001), chest circumference increased by 10.5 cm. The peak increase in ST (+1.36 cm per decade) was attained between the 1964 and the 1990 BiCo. The data on body dimensions of RU females available only from the 1960s to 1990. The ST of rural females has not changed, but the absolute and the relative (to ST) values of pelvic width of the 1980 - 1989 BiCo are significantly (p < 0.05) lower than in the 1966 - 1975 and 1965 BiCo. The RU urban females of the 1985 BiCo are 3.6 cm taller than 1964 BiCo (p < 0.001), but over the next 5 years the ST decreased by 2 cm (p = 0.06). The relative pelvic width has decreased from 17.57 % (BiCo 1965 - 1969) to 17.18 % (BiCo 1980 - 1989; p < 0.05). Menarcheal age of Perm females declined from 14.5 yrs in the 1930 - 1939 BiCo to 13.3 yrs in 1950 - 1965 BiCo, then ceased to change. The changes across generations in rural KP were weak. The rural males born in 1885 were 2.1 cm taller than BiCo 1861 - 1865. From the 1925 to 1975 BiCo the average ST increased by 6.2 cm (1.24 cm/decade). KP rural females became 6.4 cm taller from the 1885 to 1985 BiCo. Pelvic width in the 1985 BiCo (27.4 cm) is significantly bigger (p < 0.05) than in the 1975 BiCo (26.9 cm). The changes in ST of urban KP females were more obvious than in rural groups. The 1985 BiCo of urban KP females (ST 161.8 cm) are taller than those born in 1965 (159.4 cm; p < 0.05), but their pelvic width does not differ. In urban and rural KP females age at menarche is earlier in the 1976 - 1985 than in the 1966 - 1975 BiCo (p < 0.01). In all the KP cohorts, urban females have earlier menarche than rural (p < 0.05).

Women Build Long Bones With Less Cortical Mass Relative to Body Size and Bone Size Compared With Men.

BACKGROUND: The twofold greater lifetime risk of fracturing a bone for white women compared with white men and black women has been attributed in part to differences in how the skeletal system accumulates bone mass during growth. On average, women build more slender long bones with less cortical area compared with men. Although slender bones are known to have a naturally lower cortical area compared with wider bones, it remains unclear whether the relatively lower cortical area of women is consistent with their increased slenderness or is reduced beyond that expected for the sex-specific differences in bone size and body size. Whether this sexual dimorphism is consistent with ethnic background and is recapitulated in the widely used mouse model also remains unclear. QUESTIONS/PURPOSES: We asked (1) do black women build bones with reduced cortical area compared with black men; (2) do white women build bones with reduced cortical area compared with white men; and (3) do female mice build bones with reduced cortical area compared with male mice? METHODS: Bone strength and cross-sectional morphology of adult human and mouse bone were calculated from quantitative CT images of the femoral midshaft. The data were tested for normality and regression analyses were used to test for differences in cortical area between men and women after adjusting for body size and bone size by general linear model (GLM). RESULTS: Linear regression analysis showed that the femurs of black women had 11% lower cortical area compared with those of black men after adjusting for body size and bone size (women: mean=357.7 mm2; 95% confidence interval [CI], 347.9-367.5 mm2; men: mean=400.1 mm2; 95% CI, 391.5-408.7 mm2; effect size=1.2; p<0.001, GLM). Likewise, the femurs of white women had 12% less cortical area compared with those of white men after adjusting for body size and bone size (women: mean=350.1 mm2; 95% CI, 340.4-359.8 mm2; men: mean=394.3 mm2; 95% CI, 386.5-402.1 mm2; effect size=1.3; p<0.001, GLM). In contrast, female and male femora from recombinant inbred mouse strains showed the opposite trend; femurs from female mice had a 4% larger cortical area compared with those of male mice after adjusting for body size and bone size (female: mean=0.73 mm2; 95% CI, 0.71-0.74 mm2; male: mean=0.70 mm2; 95% CI, 0.68-0.71 mm2; effect size=0.74; p=0.04, GLM). CONCLUSIONS: Female femurs are not simply a more slender version of male femurs. Women acquire substantially less mass (cortical area) for their body size and bone size compared with men. Our analysis questions whether mouse long bone is a suitable model to study human sexual dimorphism. CLINICAL RELEVANCE: Identifying differences in the way bones are constructed may be clinically important for developing sex-specific diagnostics and treatment strategies to reduce fragility fractures.