Trajectories of femoral neck strength in relation to the final menstrual period in a multi-ethnic cohort

Changes in Collagen Type I C-Telopeptide and Procollagen Type I N-Terminal Propeptide During the Menopause Transition

CONTEXT

Collagen type I C-telopeptide (CTX) and procollagen type I N-terminal propeptide (PINP) are reference bone resorption and formation markers, respectively.

OBJECTIVE

To characterize CTX and PINP trajectories across the menopause transition (MT).

METHODS

This 18-year longitudinal analysis of a community-based cohort from the Study of Women's Health Across the Nation included 541 women (126 Black, 90 Chinese, 87 Japanese, 238 White) who transitioned from pre- to postmenopause. Multivariable mixed effects regression fit piecewise linear models of CTX or PINP relative to years from final menstrual period (FMP); covariates were race/ethnicity, body mass index (BMI), and age at FMP. In the referent participant (White, 52.46 years at FMP, BMI 27.12 kg/m2), CTX and PINP were stable until 3 years pre-FMP (premenopause). During the MT (3 years before to 3 years after the FMP), CTX and PINP increased 10.3% (P < .0001) and 7.5% (P < .0001) per year, respectively; MT-related gains totaled 61.9% for CTX and 45.2% for PINP. Starting 3 years post-FMP (postmenopause), CTX and PINP decreased 3.1% (P < .0001) and 2.9% (P < .0001) per year, respectively. Compared with the White participants, during the MT, Chinese participants had larger gains in CTX (P = .01), and Japanese women experienced greater increases in CTX (P < .0001) and PINP (P = .02). In postmenopause, CTX (P = .01) and PINP (P = .01) rose more in Japanese relative to White women.

CONCLUSION

CTX and PINP are stable in premenopause, increase during the MT, and decrease in postmenopause. During the MT and postmenopause, bone turnover change rates vary by race/ethnicity.

Menopause is associated with bone loss, particularly at the distal radius, in black South African women: Findings from the Study of Women Entering and in Endocrine Transition (SWEET)

Menopause transition is associated with accelerated bone loss, though data are limited from sub-Saharan African (SSA). Our objective was to describe bone density, geometry and estimated strength in women by menopause status and to explore whether patterns differed within those living with HIV.

METHODS

Radius and tibia peripheral QCT data were collected for Black South African women (n = 430) aged 40-61 years with verified menopause and HIV status. pQCT outcomes were distal 4 % radius and tibia total cross-sectional area (CSA), total volumetric bone mineral density (vBMD), and compressive bone strength (BSIc); proximal 66 % radius and 38 % tibia cortical vBMD, total CSA, cortical thickness, and Stress-strain Index (SSI). Linear regression assessed associations between pre, peri-, and postmenopausal groups and pQCT outcomes adjusting for age, height, and weight, and then stratified by HIV status. Mean [95%CI] and tests for trend (p-trend) across menopausal groups are presented.

RESULTS

Women were mean (SD) age 49.2 (5.3) years, with a body mass index (BMI) of 32.4 (6.3) m/kg², and 18 % were living with HIV. After adjustment, later menopause stage was associated with lower 4 % radius total mean [95%CIs] vBMD (premenopause: 345.7 [335.8,355.5] vs. postmenopause: 330.1 [322.7,337.6] mg/cm³, p-trend = 0.017) and BSIc (premenopause: 0.39 [0.37,0.41] vs. postmenopause: 0.36 [0.35,0.37] g²/cm⁴; p-trend = 0.012). Similar trends were observed at the 66 % radius for cortical vBMD (premenopause: 1146.8 [1138.9,1154.6] vs. postmenopause: 1136.1 [1130.1,1142.0] mg/cm³; p-trend = 0.028) and cortical thickness (premenopause: 2.01 [1.95,2.06] vs. postmenopause: 1.93 [1.89,1.98] mm; p-trend = 0.036). After stratification by HIV status a similar patten was observed in women with HIV (cortical vBMD premenopause: 1152.9 [1128.5,1177.2] mg/cm³ vs. postmenopause: 1123.6 [1106.0,1141.2] mg/cm³, p-trend = 0.048). Total CSA varied little by menopause or HIV status at either radius sites; few differences were found at the tibia.

CONCLUSION

In black South African women, menopause is associated with lower bone density and strength at the distal radius, a common site of osteoporotic fracture, in addition to lower cortical density and thickness at the proximal radius. Although the sample size was small, following stratification by HIV, women living with HIV had evidence of lower cortical density across menopause stages, unlike those without HIV. These findings raise concern for the incidence of Colles' fractures in postmenopausal women in South Africa; longitudinal studies of fracture incidence and implications of living with HIV are required.

Associations of Age at Menopause With Postmenopausal Bone Mineral Density and Fracture Risk in Women

CONTEXT

Menopause before age 45 is a risk factor for fractures, but menopause occurs at age ≥45 in ~90% of women.

OBJECTIVE

To determine, in women with menopause at age ≥45, whether (1) years since the final menstrual period (FMP) is more strongly associated with postmenopausal bone mineral density (BMD) than chronological age and (2) lower age at FMP is related to more fractures.

DESIGN AND SETTING

The Study of Women's Health Across the Nation, a longitudinal cohort study of the menopause transition (MT).

PARTICIPANTS

A diverse cohort of ambulatory women (pre- or early perimenopausal at baseline, with 15 near-annual follow-up assessments).

MAIN OUTCOME MEASURES

Postmenopausal lumbar spine (LS) or femoral neck (FN) BMD (n = 1038) and time to fracture (n = 1554).

RESULTS

Adjusted for age, body mass index (BMI), cigarette use, alcohol intake, baseline LS or FN BMD, baseline MT stage, and study site using multivariable linear regression, each additional year after the FMP was associated with 0.006 g/cm2 (P < 0.0001) and 0.004 g/cm2 (P < 0.0001) lower postmenopausal LS and FN BMD, respectively. Age was not related to FN BMD independent of years since FMP. In Cox proportional hazards regression, accounting for race/ethnicity, BMI, cigarette use, alcohol intake, prior fracture, diabetes status, exposure to bone-modifying medications/supplements, and study site, the hazard for incident fracture was 5% greater for each 1-year decrement in age at FMP (P = 0.02).

CONCLUSIONS

Years since the FMP is more strongly associated with postmenopausal BMD than chronological age, and earlier menopause is associated with more fractures.

The combined effects of age and HIV on the anatomic distribution of cortical and cancellous bone in the femoral neck among men and women

OBJECTIVE

To investigate HIV-related and age-related differences in hip bone structure in men and women.

DESIGN

Cross sectional study of bone structure and HIV serostatus.

METHODS

We used Quantitative Computed Tomography (QCT) data from the Multicenter AIDS Cohort Study (MACS) and Women's Interagency HIV Study (WIHS) to examine cortical thickness (CT) and cortical (CBMD), trabecular (TBMD), and integral (IBMD) bone mineral density across anatomic quadrants of the femoral neck in older adult MSM and women with (PWH) and without (PWOH) HIV infection. The percentage difference (%diff) in the means for CT and BMD overall and by quadrant between PWH and PWOH were estimated.

RESULTS

Among 322 MSM (median age 60 years) with bone measures, distributions were similar between HIV serostatus groups with %diff in the quadrant means ranging from -7 to -1% for CT and from -1 to 4% for BMD, and overall lower hip cortical thickness than expected. In contrast, in 113 women (median age 51 years), PWH had lower CT, IBMD and TBMD consistently across all quadrants, with differences ranging from -10 to -20% for CT, -6 to -11% for IBMD and -3 to -6% for TBMD. Estimates reached statistical significance in superoanterior quadrant for CT and IBMD and inferoposterior for CT.

CONCLUSION

Among women, PWH appear to have a thinner cortex and less dense integral bone compared with PWOH, particularly in the superior quadrants whereas MSM overall had a thinner than expected hip cortex.

Faster Lumbar Spine Bone Loss in Midlife Predicts Subsequent Fracture Independent of Starting Bone Mineral Density

CONTEXT

Bone mineral density (BMD) decreases rapidly during menopause transition (MT), and continues to decline in postmenopause.

OBJECTIVE

This work aims to examine whether faster BMD loss during the combined MT and early postmenopause is associated with incident fracture, independent of starting BMD, before the MT.

METHODS

The Study of Women's Health Across the Nation, a longitudinal cohort study, included 451 women, initially premenopausal or early perimenopausal, and those transitioned to postmenopause. Main outcome measures included time to first fracture after early postmenopause.

RESULTS

In Cox proportional hazards regression, adjusted for age, body mass index, race/ethnicity, study site, use of vitamin D and calcium supplements, and use of bone-detrimental or -beneficial medications, each SD decrement in lumbar spine (LS) BMD before MT was associated with a 78% increment in fracture hazard (P = .007). Each 1% per year faster decline in LS BMD was related to a 56% greater fracture hazard (P = .04). Rate of LS BMD decline predicted future fracture, independent of starting BMD. Women with a starting LS BMD below the sample median, and an LS BMD decline rate faster than the sample median had a 2.7-fold greater fracture hazard (P = .03). At the femoral neck, neither starting BMD nor rate of BMD decline was associated with fracture.

CONCLUSION

At the LS, starting BMD before the MT and rate of decline during the combined MT and early postmenopause are independent risk factors for fracture. Women with a below-median starting LS BMD and a faster-than-median LS BMD decline have the greatest fracture risk.

Hormones and bone loss across the menopause transition

The menopause transition is a critical period for bone health in women, with rapid losses in bone mass and strength occurring over an approximately 3-year window bracketing the date of the final menstrual period. The onset of the rapid bone loss phase is preceded by large changes in sex steroid hormones, measurements of which may be clinically useful in predicting the onset of the rapid loss phase and identifying the women who will lose the most bone mass during this rapid bone loss phase. Here we summarize recent and new findings related to the ability of sex hormone levels to (1) determine if a woman in her 5th decade of life is about to enter or has already entered the rapid phase of bone loss, and (2) if she will lose more than the average amount of bone mass over the menopause transition.

Dietary protein and bone health: towards a synthesised view

The present paper reviews published literature on the relationship between dietary protein and bone health. It will include arguments both for and against the anabolic and catabolic effects of dietary protein on bone health. Adequate protein intake provides the amino acids used in building and maintaining bone tissue, as well as stimulating the action of insulin-like growth factor 1, which in turn promotes bone growth and increases calcium absorption. However, the metabolism of dietary sulphur amino acids, mainly from animal protein, can lead to increased physiological acidity, which may be detrimental for bone health in the long term. Similarly, cereal foods contain dietary phytate, which in turn contains phosphate. It is known that phosphate consumption can also lead to increased physiological acidity. Therefore, cereal products may produce as much acid as do animal proteins that contain sulphur amino acids. The overall effect of dietary protein on physiological acidity, and its consequent impact on bone health, is extremely complex and somewhat controversial. The consensus is now moving towards a synthesised approach. Particularly, how anabolic and catabolic mechanisms interact; as well as how the context of the whole diet and the type of protein consumed is important.

Trabecular Bone Score Declines During the Menopause Transition: The Study of Women's Health Across the Nation (SWAN)

CONTEXT

Rapid bone density loss starts during the menopause transition (MT). Whether other components of bone strength deteriorate before the final menstrual period (FMP) remains uncertain.

OBJECTIVE

To discern whether trabecular bone score (TBS) declines during the MT.

DESIGN

An 18-year longitudinal analysis from the Study of Women's Health Across Nation.

SETTING

Community-based cohort.

PARTICIPANTS

A total of 243 black, 164 Japanese, and 298 white, initially pre- or early perimenopausal women, who experienced their FMP.

MAIN OUTCOME MEASURES

TBS, an indicator of bone strength.

RESULTS

Multivariable mixed effects regressions fitted piecewise linear models to repeated measures of TBS as a function of time before or after the FMP; covariates were age at FMP, race/ethnicity, and body mass index. Prior to 1.5 years before the FMP, in the referent individual (a white woman with age at FMP of 52.2 years and body mass index of 28.0 kg/m2), TBS evidenced no change (slope 0.12% per year, P = 0.2991). TBS loss began 1.5 years before the FMP, declining by 1.16% annually (P < 0.0001). Starting 2 years after the FMP, annual rate of TBS loss lessened to 0.89% (P < 0.0001). In the 5 years before through the 5 years after the FMP, in the referent individual, total TBS decline was 6.3% (P < 0.0001), but black participants' total TBS loss was 4.90% (P = 0.0008, difference in black and white 10-year change). Results for Japanese did not differ from those of white women.

CONCLUSIONS

The occurrence of an MT-related decline in TBS supports the thesis that this period is particularly damaging to skeletal integrity.

A bone resorption marker as predictor of rate of change in femoral neck size and strength during the menopause transition

We assessed whether a bone resorption marker, measured early in the menopause transition (MT), is associated with change in femoral neck size and strength during the MT. Higher levels of bone resorption were associated with slower increases in femoral neck size and faster decreases in femoral neck strength.

PURPOSE

Composite indices of the femoral neck's ability to withstand compressive (compression strength index, CSI) and impact (impact strength index, ISI) forces integrate DXA-derived femoral neck width (FNW), bone mineral density (BMD), and body size. During the menopause transition (MT), FNW increases, and CSI and ISI decrease. This proof-of-concept study assessed whether a bone resorption marker, measured early in the MT, is associated with rates of change in FNW, CSI and ISI during the MT.

METHODS

We used previously collected bone resorption marker (urine collagen type I N-telopeptide [U-NTX]) and femoral neck strength data from 696 participants from the Study of Women's Health Across the Nation (SWAN), a longitudinal study of the MT in a multi-ethnic cohort of community-dwelling women.

RESULTS

Adjusted for MT stage (pre- vs. early perimenopause), age, body mass index (BMI), bone resorption marker collection time, and study site in multivariable linear regression, bone resorption in pre- and early perimenopause was not associated with transmenopausal decline rate in femoral neck BMD. However, each standard deviation (SD) increase in bone resorption level was associated with 0.2% per year slower increase in FNW (p = 0.03), and 0.3% per year faster declines in CSI (p = 0.02) and ISI (p = 0.01). When restricted to women in early perimenopause, the associations of bone resorption with change in FNW, CSI, and ISI were similar to those in the full sample.

CONCLUSIONS

Measuring a bone resorption marker in pre- and early perimenopause may identify women who will experience the greatest loss in bone strength during the MT.

The menopause transition and women's health at midlife: a progress report from the Study of Women's Health Across the Nation (SWAN)

OBJECTIVE

Our initial understanding of the menopause transition (MT) has been framed by clinical samples of women seeking treatment rather than by population-based studies. The Study of Women's Health Across the Nation (SWAN) initiated in 1996 with an overall goal to define the MT, to characterize its biological and psychosocial antecedents and sequelae in an ethnically and racially diverse sample of midlife women.

METHODS

This review summarizes the central findings of SWAN to date that can inform women and their healthcare providers about the impact of the MT and midlife aging on overall health and well-being.

RESULTS

SWAN characterized changes in reproductive axis and menstrual cycle patterns that informed the development of the reproductive aging staging system Staging of Reproductive Aging Workshop+10; MT-related symptoms and mental health (vasomotor symptoms, sleep complaints, psychological symptoms, cognitive performance, and urogenital and sexual health); and physiological systems and functions (cardiovascular and cardiometabolic health, bone health, physical function performance) that are influenced by the MT. SWAN demonstrated substantial interrelations among these changes and significant racial/ethnic differences in the rate and magnitude of change in multiple health indictors in midlife women. The findings point to midlife as a critical stage for adopting healthy behavior and preventive strategies.

CONCLUSIONS

Over the past 23 years, SWAN has advanced our understanding of the impact of the MT and midlife aging on health and well-being in women. SWAN will be instrumental to determine whether MT-related changes during midlife are related to unfavorable health and well-being in early old age.

External Bone Size Is a Key Determinant of Strength-Decline Trajectories of Aging Male Radii

Given prior work showing associations between remodeling and external bone size, we tested the hypothesis that wide bones would show a greater negative correlation between whole-bone strength and age compared with narrow bones. Cadaveric male radii (n = 37 pairs, 18 to 89 years old) were evaluated biomechanically, and samples were sorted into narrow and wide subgroups using height-adjusted robustness (total area/bone length). Strength was 54% greater (p < 0.0001) in wide compared with narrow radii for young adults (<40 years old). However, the greater strength of young-adult wide radii was not observed for older wide radii, as the wide (R² = 0.565, p = 0.001), but not narrow (R² = 0.0004, p = 0.944) subgroup showed a significant negative correlation between strength and age. Significant positive correlations between age and robustness (R² = 0.269, p = 0.048), cortical area (Ct.Ar; R² = 0.356, p = 0.019), and the mineral/matrix ratio (MMR; R² = 0.293, p = 0.037) were observed for narrow, but not wide radii (robustness: R² = 0.015, p = 0.217; Ct.Ar: R² = 0.095, p = 0.245; MMR: R² = 0.086, p = 0.271). Porosity increased with age for the narrow (R² = 0.556, p = 0.001) and wide (R² = 0.321, p = 0.022) subgroups. The wide subgroup (p < 0.0001) showed a significantly greater elevation of a new measure called the Cortical Pore Score, which quantifies the cumulative effect of pore size and location, indicating that porosity had a more deleterious effect on strength for wide compared with narrow radii. Thus, the divergent strength-age regressions implied that narrow radii maintained a low strength with aging by increasing external size and mineral content to mechanically offset increases in porosity. In contrast, the significant negative strength-age correlation for wide radii implied that the deleterious effect of greater porosity further from the centroid was not offset by changes in outer bone size or mineral content. Thus, the low strength of elderly male radii arose through different biomechanical mechanisms. Consideration of different strength-age regressions (trajectories) may inform clinical decisions on how best to treat individuals to reduce fracture risk. © 2019 American Society for Bone and Mineral Research.

Longitudinal changes in hip geometry in relation to the final menstrual period: Study of Women's Health Across the Nation (SWAN)

BACKGROUND

In SWAN, we showed that accelerated loss of bone mineral density (BMD) begins 1 year before the final menstrual period (FMP) to 2 years after the FMP and slows thereafter. However, the risk of fracture depends on both BMD and bone geometry. The hip structural analysis (HSA) measures important geometric properties of bone. Changes in HSA parameters across the menopausal transition have not been previously assessed.

METHODS

The current analysis uses data from SWAN, 5 years before to 5 years after FMP (N = 900, Age (mean(SD)) = 46.85(2.60), 44% White). HSA parameters at the femoral narrow neck were obtained from 2D DXA scans and normalized to baseline values. FMP was determined from annual interviews. Changes in HSA were assessed over 3 periods, 5 to 2 years before FMP (pre-transmenopausal), 2 years before to 1 years after FMP (transmenopausal), 1 to 5 years after FMP (postmenopausal). Mixed linear models with random slopes were used to estimate the rate of change in HSA parameters relative to FMP.

RESULTS

Loss of BMD, cross-sectional area (CSA), and section modulus (SM) and increases in outer diameter (OD) were greatest in the transmenopausal period (p for all<0.05). Changes continued in the postmenopausal period but were not statistically significant. The cumulative percentage changes over 10 years in BMD (-10.67%), CSA (-9.01), SM (-7.03) and OD (+1.95) were statistically significant.

CONCLUSION

Changes in hip geometry across the menopause transition parallel changes in BMD and provide insight into mechanisms that may increase risk of fragility fracture.

Bone Health During the Menopause Transition and Beyond

The menopause transition is a critical period for bone health, with rapid losses in bone mass and strength occurring in a 3-year window bracketing the date of the final menstrual period. Declines in bone mass are accompanied by deleterious changes in bone macrostructure and microarchitecture, which may be captured by changes in composite strength indices and indices of trabecular thickness and connectivity. The onset of the rapid bone loss phase is preceded by changes in sex steroid hormones and increases in markers of bone resorption, measurements of which may be clinically useful in predicting the onset of the rapid loss phase and in identifying the women who will lose the most bone strength over the menopause transition.

Change in sexual functioning over the menopausal transition: results from the Study of Women's Health Across the Nation

OBJECTIVE

The aim of the study was to identify whether there is a decline in sexual functioning related to the menopausal transition or to hysterectomy.

METHODS

In a cohort of 1,390 women aged 42 to 52, with intact uterus and at least one ovary, not using hormone therapy, and pre- or early perimenopausal at baseline, we fit piecewise linear growth curves to 5,798 repeated measurements (seven visits spanning 14.5 y) of a sexual functioning score (range, 5-25) as a function of time relative to date of final menstrual period (FMP) or hysterectomy.

RESULTS

Mean sexual functioning at baseline in women with a dateable FMP was 18.0 (SD, 3.4). There was no change in sexual function until 20 months before the FMP. From 20 months before until 1 year after the FMP, sexual function decreased by 0.35 annually (95% CI, -0.44 to -0.26) and continued to decline more than 1 year after the FMP, but at a slower rate (-0.13 annually, 95% CI, -0.17 to -0.10). The decline was smaller in African Americans and larger in Japanese than whites. Vaginal dryness, lubricant use, depressive symptoms, or anxiety did not explain decline in sexual function. Women who had a hysterectomy before the FMP did not show a decline in sexual function before hysterectomy, but scores declined afterward (0.21 annually, 95% CI, -0.28 to -0.14).

CONCLUSIONS

Decline in sexual function became apparent 20 months before FMP and slowed 1 year after FMP through 5 years afterward. A decline in sexual function was observed immediately after hysterectomy and persisted for the 5 years of observation.

Femoral Neck External Size but not aBMD Predicts Structural and Mass Changes for Women Transitioning Through Menopause

The impact of adult bone traits on changes in bone structure and mass during aging is not well understood. Having shown that intracortical remodeling correlates with external size of adult long bones led us to hypothesize that age-related changes in bone traits also depend on external bone size. We analyzed hip dual-energy X-ray absorptiometry images acquired longitudinally over 14 years for 198 midlife women transitioning through menopause. The 14-year change in bone mineral content (BMC, R²  = 0.03, p = 0.015) and bone area (R²  = 0.13, p = 0.001), but not areal bone mineral density (aBMD, R²  = 0.00, p = 0.931) correlated negatively with baseline femoral neck external size, adjusted for body size using the residuals from a linear regression between baseline bone area and height. The dependence of the 14-year changes in BMC and bone area on baseline bone area remained significant after adjusting for race/ethnicity, postmenopausal hormone use, the 14-year change in weight, and baseline aBMD, weight, height, and age. Women were sorted into tertiles using the baseline bone area-height residuals. The 14-year change in BMC (p = 0.009) and bone area (p = 0.001) but not aBMD (p = 0.788) differed across the tertiles. This suggested that women showed similar changes in aBMD for different structural and biological reasons: women with narrow femoral necks showed smaller changes in BMC but greater increases in bone area compared to women with wide femoral necks who showed greater losses in BMC but without large compensatory increases in bone area. This finding is opposite to expectations that periosteal expansion acts to mechanically offset bone loss. Thus, changes in femoral neck structure and mass during menopause vary widely among women and are predicted by baseline external bone size but not aBMD. How these different structural and mass changes affect individual strength-decline trajectories remains to be determined. © 2017 American Society for Bone and Mineral Research.

Moving toward a prevention strategy for osteoporosis by giving a voice to a silent disease

A major unmet challenge in developing preventative treatment programs for osteoporosis is that the optimal timing of treatment remains unknown. In this commentary we make the argument that the menopausal transition (MT) is a critical period in a woman's life for bone health, and that efforts aimed at reducing fracture risk later in life may benefit greatly from strategies that treat women earlier with the intent of keeping bones strong as long as possible. Bone strength is an important parameter to monitor during the MT because engineering principles can be applied to differentiate those women that maintain bone strength from those women that lose bone strength and are in need of early treatment. It is critical to understand the underlying mechanistic causes for reduced strength to inform treatment strategies. Combining measures of strength with data on how bone structure changes during the MT may help differentiate whether a woman is losing strength because of excessive bone resorption, insufficient compensatory bone formation, trabeculae loss, or some combination of these factors. Each of these biomechanical mechanisms may require a different treatment strategy to keep bones strong. The technologies that enable physicians to differentially diagnose and treat women in a preventive manner, however, have lagged behind the development of prophylactic treatments for osteoporosis. To take advantage of these treatment options, advances in preventive treatment strategies for osteoporosis may require developing new technologies with imaging resolutions that match the pace by which bone changes during the MT and supplementing a woman's bone mineral density (BMD)-status with information from engineering-based analyses that reveal the structural and material changes responsible for the decline in bone strength during the menopausal transition.

Bone health after menopause

PURPOSE OF REVIEW

This article reviews recent publications (January 2014-June 2015) on bone health and menopause.

RECENT FINDINGS

Recent articles suggest that simple instruments, such as the osteoporosis self-assessment tool based on age and weight may identify women age 50-64 for bone mineral density (BMD) testing. Rescreening of women age 50-64 is not recommended because their overall risk of fracture is quite low. A novel risk factor for hip fracture among non-Caucasian women is socioeconomic status. Midlife women with low serum 25-hydroxyvitamin D (<20 ng/ml) have an increased risk of fracture over the menopausal transition and vitamin D supplementation is warranted. Wrist fractures are the most common fracture in women age 50-64. Women who experience a wrist fracture have an increased risk of subsequent fracture and should have a BMD scan. Results of studies using composite measures of femoral neck strength relative to load emphasize the need for osteoporotic research to move beyond BMD.

SUMMARY

This recent research has provided new and important findings improving our understanding of osteoporosis during the menopausal transition.

Socioeconomic status in relation to incident fracture risk in the Study of Women's Health Across the Nation

We examined baseline and annual follow-up data (through annual follow-up visit 9) from a cohort of 2,234 women aged 42 to 52 years at baseline. Independent of financial status, higher educational level was associated with lower fracture incidence among non-Caucasian women but not among Caucasian women.

INTRODUCTION

This study was conducted to determine the associations of education and income with fracture incidence among midlife women over 9 years of follow-up.

METHODS

We examined baseline and annual follow-up data (through annual follow-up visit 9) from 2,234 participants of the Study of Women's Health Across the Nation, a cohort of women aged 42 to 52 years at baseline. We used Cox proportional hazards regression models to examine the associations of socioeconomic predictors (education, family-adjusted poverty-to-income ratio, and difficulty paying for basics) with time to first incident nontraumatic, nondigital, noncraniofacial fracture.

RESULTS

Independent of family-adjusted poverty-to-income ratio, higher educational level was associated with decreased time to first incident fracture among non-Caucasian women but not among Caucasian women (p(interaction) 0.02). Compared with non-Caucasian women who completed no more than high school education, non-Caucasian women who attained at least some postgraduate education had 87% lower rates of incident nontraumatic fracture (adjusted hazard ratio 0.13, 95% confidence interval [CI] 0.03-0.60). Among non-Caucasian women, each additional year of education was associated with a 16% lower odds of nontraumatic fracture (adjusted odds ratio 0.84, 95% CI 0.73-0.97). Income, family-adjusted poverty-to-income ratio, and degree of difficulty paying for basic needs were not associated with time to first fracture in Caucasian or non-Caucasian women.

CONCLUSIONS

Among non-Caucasian midlife women, higher education, but not higher income, was associated with lower fracture incidence. Elucidation of the mechanisms underlying the possible protective effects of higher educational level on nontraumatic fracture incidence may allow us to better target individuals at risk of future fracture.

Physical activity as determinant of femoral neck strength relative to load in adult women: findings from the hip strength across the menopause transition study

Our objective was to examine associations of physical activity in different life domains with peak femoral neck strength relative to load in adult women. Greater physical activity in each of the domains of sport, active living, home, and work was associated with higher peak femoral neck strength relative to load.

INTRODUCTION

Our objective was to examine the associations of physical activity in different life domains with peak femoral neck strength relative to load in adult women. Composite indices of femoral neck strength integrate body size with femoral neck size and bone mineral density to gauge bone strength relative to load during a fall, and are inversely associated with incident fracture risk.

METHODS

Participants were 1,919 pre- and early perimenopausal women from the Study of Women's Health Across the Nation. Composite indices of femoral neck strength relative to load in three failure modes (compression, bending, and impact) were created from hip dual-energy X-ray absorption scans and body size. Usual physical activity within the past year was assessed with the Kaiser Physical Activity Survey in four domains: sport, home, active living, and work. We used multiple linear regression to examine the associations.

RESULTS

Greater physical activity in each of the four domains was independently associated with higher composite indices, adjusted for age, menopausal transition stage, race/ethnicity, Study of Women's Health Across the Nation study site, smoking status, smoking pack-years, alcohol consumption level, current use of supplementary calcium, current use of supplementary vitamin D, current use of bone-adverse medications, prior use of any sex steroid hormone pills or patch, prior use of depo-provera injections, history of hyperthyroidism, history of previous adult fracture, and employment status: standardized effect sizes ranged from 0.04 (p < 0.05) to 0.20 (p < 0.0001).

CONCLUSIONS

Physical activity in each domain examined was associated with higher peak femoral neck strength relative to load in pre- and early perimenopausal women.