Trends in osteoporosis and low bone mass in older US adults, 2005-2006 through 2013-2014.

This study examined trends in osteoporosis and low bone mass in older US adults between 2005 and 2014 using bone mineral density (BMD) data from the National Health and Nutrition Examination Survey (NHANES). Osteoporosis and low bone mass appear to have increased at the femur neck but not at the lumbar spine during this period. INTRODUCTION: Recent preliminary data from Medicare suggest that the decline in hip fracture incidence among older US adults may have plateaued in 2013-2014, but comparable data on BMD trends for this time period are currently lacking. This study examined trends in the prevalence of osteoporosis and low bone mass since 2005 using BMD data from NHANES. The present study also updated prevalence estimates to 2013-2014 and included estimates for non-Hispanic Asians. METHODS: Femur neck and lumbar spine BMD by DXA were available for 7954 adults aged 50 years and older from four NHANES survey cycles between 2005-2006 and 2013-2014. RESULTS: Significant trends (quadratic or linear) were observed for the femur neck (mean T-score and osteoporosis in both sexes; low bone mass in women) but not for the lumbar spine. The trend in femur neck status was somewhat U-shaped, with prevalences being most consistently significantly higher (by 1.1-6.6 percentage points) in 2013-2014 than 2007-2008. Adjusting for changes in body mass index, smoking, milk intake, and physician's diagnosis of osteoporosis between surveys did not change femur neck trends. In 2013-2014, the percent of older adults with osteoporosis was 6% at the femur neck, 8% at the lumbar spine, and 11% at either site. CONCLUSIONS: There was some evidence of a decline in femur neck BMD between 2005-2006 and 2013-2014, but not in lumbar spine BMD. Changes in the risk factors that could be examined did not explain the femur neck BMD trends.

Spine fracture prevalence in a nationally representative sample of US women and men aged ≥40 years: results from the National Health and Nutrition Examination Survey (NHANES) 2013-2014.

Spine fracture prevalence is similar in men and women, increasing from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Prevalence was higher with age, lower bone mineral density (BMD), and in those meeting criteria for spine imaging. Most subjects with spine fractures were unaware of them. INTRODUCTION: Spine fractures have substantial medical significance but are seldom recognized. This study collected contemporary nationally representative spine fracture prevalence data. METHODS: Cross-sectional analysis of 3330 US adults aged ≥40 years participating in NHANES 2013-2014 with evaluable Vertebral Fracture Assessment (VFA). VFA was graded by semiquantitative measurement. BMD and an osteoporosis questionnaire were collected. RESULTS: Overall spine fracture prevalence was 5.4 % and similar in men and women. Prevalence increased with age from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Fractures were more common in non-Hispanic whites and in people with lower body mass index and BMD. Among subjects with spine fracture, 26 % met BMD criteria for osteoporosis. Prevalence was higher in subjects who met National Osteoporosis Foundation (NOF) criteria for spine imaging (14 vs 4.7 %, P < 0.001). Only 8 % of people with a spine fracture diagnosed by VFA had a self-reported fracture, and among those who self-reported a spine fracture, only 21 % were diagnosed with fracture by VFA. CONCLUSION: Spine fracture prevalence is similar in women and men and increases with age and lower BMD, although most subjects with spine fracture do not meet BMD criteria for osteoporosis. Since most (>90 %) individuals were unaware of their spine fractures, lateral spine imaging is needed to identify these women and men. Spine fracture prevalence was threefold higher in individuals meeting NOF criteria for spine imaging (∼1 in 7 undergoing VFA). Identifying spine fractures as part of comprehensive risk assessment may improve clinical decision making.

Trabecular bone scores and lumbar spine bone mineral density of US adults: comparison of relationships with demographic and body size variables.

UNLABELLED: This study examines demographic patterns and body size relationships in trabecular bone score and lumbar spine BMD of US adults from NHANES 2005-2008. INTRODUCTION: Limited data exist on demographic and body size relationships for trabecular bone score (TBS), a new variable derived from bone texture analysis of lumbar spine dual-energy X-ray absorptiometry (DXA) scans. This study compares demographic patterns and correlations with body size (body mass index (BMI), weight, waist circumference, total body fat, trunk fat, trunk lean) between TBS and lumbar spine bone mineral density (LSBMD) for adults age ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 2005-2008 with BMI in the optimal range for TBS (15-37 kg/m(2)). METHODS: LSBMD, TBS, body fat, and lean were obtained by DXA. Weight, height, and waist circumference were measured. BMI was calculated from height and weight. RESULTS: Sex differences in TBS varied by age and race/ethnicity (p sex X age interaction and p sex X race/ethnicity interaction < 0.001). In most of the nine demographic subgroups examined, TBS did not differ by sex (four subgroups) or was significantly higher in women (three subgroups). TBS differences by race/ethnicity were inconsistent in men; in women, non-Hispanic whites (NHWs) had higher TBS than non-Hispanic blacks (NHBs) or Mexican Americans (MAs) in all age groups. In contrast, LSBMD was either significantly higher in men (five subgroups) or did not differ by sex (four subgroups). Race/ethnic differences in LSBMD were consistent across age and sex (NHB > NHW > MA). All body size variables were negatively related to TBS but positively related to LSBMD. CONCLUSIONS: Demographic patterns and body size relationships differed between TBS and LSBMD.

Calcium plus vitamin D supplementation and risk of fractures: an updated meta-analysis from the National Osteoporosis Foundation.

UNLABELLED: The aim was to meta-analyze randomized controlled trials of calcium plus vitamin D supplementation and fracture prevention. Meta-analysis showed a significant 15 % reduced risk of total fractures (summary relative risk estimate [SRRE], 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87). INTRODUCTION: Calcium plus vitamin D supplementation has been widely recommended to prevent osteoporosis and subsequent fractures; however, considerable controversy exists regarding the association of such supplementation and fracture risk. The aim was to conduct a meta-analysis of randomized controlled trials [RCTs] of calcium plus vitamin D supplementation and fracture prevention in adults. METHODS: A PubMed literature search was conducted for the period from July 1, 2011 through July 31, 2015. RCTs reporting the effect of calcium plus vitamin D supplementation on fracture incidence were selected from English-language studies. Qualitative and quantitative information was extracted; random-effects meta-analyses were conducted to generate summary relative risk estimates (SRREs) for total and hip fractures. Statistical heterogeneity was assessed using Cochran's Q test and the I (2) statistic, and potential for publication bias was assessed. RESULTS: Of the citations retrieved, eight studies including 30,970 participants met criteria for inclusion in the primary analysis, reporting 195 hip fractures and 2231 total fractures. Meta-analysis of all studies showed that calcium plus vitamin D supplementation produced a statistically significant 15 % reduced risk of total fractures (SRRE, 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87). Numerous sensitivity and subgroup analyses produced similar summary associations. A limitation is that this study utilized data from subgroup analysis of the Women's Health Initiative. CONCLUSIONS: This meta-analysis of RCTs supports the use of calcium plus vitamin D supplements as an intervention for fracture risk reduction in both community-dwelling and institutionalized middle-aged to older adults.

Dysmobility syndrome and mortality risk in US men and women age 50 years and older.

UNLABELLED: Mortality risk was significantly elevated in older adults from NHANES 1999-2002 with dysmobility syndrome. INTRODUCTION: Dysmobility syndrome was recently proposed as an approach to evaluate the musculoskeletal health of older persons, but data linking this syndrome to adverse outcomes are currently lacking. The present study used data from the National Health and Nutrition Examination Survey (NHANES) 1999-2002 to assess the relationship between dysmobility and mortality in adults age 50 years and older by age, sex, and race or ethnicity. METHODS: Dysmobility was defined as three or more of the following: high body fat, osteoporosis, low muscle mass, low muscle strength, slow gait speed, or falling risk. Body composition and bone density were assessed with dual energy X-ray absorptiometry. Gait speed was measured via a timed walk, muscle strength via isokinetic knee extension, and fall risk via self-reported balance problems in the past year. Hazard ratios (HRs) for mortality were calculated with Cox proportional hazard models. RESULTS: Twenty-two percent of adults age 50+ years had dysmobility in 1999-2002. Mortality risk by dysmobility varied significantly by age (pinteraction = 0.001). HRs for those aged 50-69 years were 3.63 (95% confidence interval (CI) 2.69, 4.90) and 2.59 (95% CI 1.82, 3.69), respectively, before and after adjusting for all confounders, compared with 1.46 (95% CI 1.07, 1.99) and 1.23 (95% CI 0.89, 1.69) for those aged 70+ years. The relationship was significant when examined by sex or race/ethnicity within age group for most subgroups. CONCLUSIONS: Dysmobility was associated with increased mortality risk in adults age 50 years and older, with risk being higher in those age 50-69 years than in those age 70+ years.

Hemoglobin and hip fracture risk in older non-Hispanic white adults.

SUMMARY: The relationship between hemoglobin and hip fracture was examined in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III). Both low and high hemoglobin values were associated with increased hip fracture risk before and after adjusting for selected risk factors. INTRODUCTION: The few studies to date that have examined the relationship between hemoglobin and fracture risk have focused on low hemoglobin values. The present study examined hip fracture risk across the hemoglobin distribution in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). METHODS: Hemoglobin was measured using a Coulter S-plus Jr.® (Coulter Electronics, Hialeah, FL) in 2,122 non-Hispanic whites age 65 years and older. Hip fracture cases were identified using linked Medicare and mortality records obtained through 2007. Cox proportional hazards models were used to assess the best-fitting model and to estimate the hazards ratio (HR) for hip fracture by hemoglobin decile before and after adjusting for selected confounders. RESULTS: There were 239 hip fracture cases in the analytic sample. The best fitting model was quadratic. When compared to values in the middle of the distribution, those with hemoglobin in the lowest and highest deciles had increased hip fracture risk (HRlowest decile = 2.96, 95 % confidence interval (CI) 1.44-6.08; HRhighest decile = 2.06, 95 % CI 1.09-3.92) after adjusting for age and sex. Both HRs remained significant after adjusting for additional confounders (HRlowest decile = 2.24, 95 % CI 1.09-3.92; HRhighest decile = 2.37, 95 % CI 1.35-4.16). CONCLUSIONS: Both low and high hemoglobin values were associated with increased hip fracture risk. The mechanism underlying the relationship is not clear, but there were some suggestions that it may differ for low versus high hemoglobin.

Relationship between femur neck bone mineral density and prevalent chronic obstructive pulmonary disease (COPD) or COPD mortality in older non-Hispanic white adults from NHANES III.

SUMMARY: The relationship between femur neck bone mineral density (FNBMD), prevalent COPD, and COPD mortality was examined in older non-Hispanic white adults from NHANES III. FNBMD was significantly related to prevalent COPD and COPD mortality before and after adjusting for shared risk factors. INTRODUCTION: Bone mineral density (BMD) has been linked to chronic obstructive pulmonary disease (COPD), but little is known about its relationship with COPD mortality. The present study examined the relationship between FNBMD, prevalent COPD, and COPD mortality in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). METHODS: COPD status at baseline was defined by self-reported physician's diagnosis and by airway obstruction based on spirometry measurements in 3,275 non-Hispanic whites aged 50 years and older. COPD mortality cases were identified using linked mortality records obtained through 2006. FNBMD was measured by dual-energy x-ray absorptiometry. Multiple regression was used to examine the baseline relationship between COPD and FNBMD. Cox proportional hazards models were used to estimate the hazards ratio (HR) for COPD mortality by FNBMD. RESULTS: Twelve percent self-reported a physician's diagnosis of COPD, 23 % had mild or moderate airway obstruction, and 9 % had severe or very severe airway obstruction. There were 180 COPD mortality cases in the sample. FNBMD was significantly lower in those with self-reported COPD diagnosis or airway obstruction before and after adjusting for shared risk factors (p < 0.05). COPD mortality risk was significantly increased for each standard deviation decline in FNBMD before (by 68 %) and after (by 26-38 %) adjusting for shared risk factors. CONCLUSIONS: Low FNBMD was associated with both baseline COPD and future COPD mortality. Shared risk factors appeared to explain some, but not all, of these relationships.

The potential impact of the National Osteoporosis Foundation guidance on treatment eligibility in the USA: an update in NHANES 2005-2008.

UNLABELLED: This analysis of National Health and Nutrition Examination Survey (NHANES) 2005-2008 data describes the prevalence of risk factors for osteoporosis and the proportions of men and postmenopausal women age 50 years and older who are candidates for treatment to lower fracture risk, according to the new Fracture Risk Assessment Tool (FRAX)-based National Osteoporosis Foundation Clinician's Guide. INTRODUCTION: It is important to update estimates of the proportions of the older US population considered eligible for pharmacologic treatment for osteoporosis for purposes of understanding the health care burden of this disease. METHODS: This is a cross-sectional study of the NHANES 2005-2008 data in 3,608 men and women aged 50 years and older. Variables in the analysis included race/ethnicity, age, lumbar spine and femoral neck bone mineral density, risk factor profiles, and FRAX 10-year fracture probabilities. RESULTS: The prevalence of osteoporosis of the femoral neck ranged from 6.0% in non-Hispanic black to 12.6% in Mexican American women. Spinal osteoporosis was more prevalent among Mexican American women (24.4%) than among either non-Hispanic blacks (5.3%) or non-Hispanic whites (10.9%). Treatment eligibility was similar in Mexican American and non-Hispanic white women (32.0% and 32.8%) and higher than it was in non-Hispanic black women (11.0%). Treatment eligibility among men was 21.1% in non-Hispanic whites, 12.6% in Mexican Americans, and 3.0% in non-Hispanic blacks. CONCLUSIONS: Nineteen percent of older men and 30% of older women in the USA are at sufficient risk for fracture to warrant consideration for pharmacotherapy.

Changes in femur neck bone density in US adults between 1988-1994 and 2005-2008: demographic patterns and possible determinants.

SUMMARY: This analysis compares femur neck bone mineral density (FNBMD) and bone determinants in adults between National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and NHANES 2005-2008. FNBMD was higher in NHANES 2005-2008 than in NHANES III, but between-survey differences varied by age, sex, and race/ethnicity. The likelihood that FNBMD has improved appears strongest for older white women. INTRODUCTION: Recent data on hip fracture incidence and femur neck osteoporosis suggest that the skeletal status of older US adults has improved since the 1990s, but the explanation for these changes remains uncertain. METHODS: The present study compares mean FNBMD of adults ages 20 years and older between the third (NHANES III, 1988-1994) and NHANES 2005-2008. Dual-energy X-ray absorptiometry systems (pencil beam in NHANES III, fan beam in NHANES 2005-2008) were used to measure hip BMD, and several bone determinants are compared between surveys to assess their potential role in explaining observed FNBMD differences. RESULTS: FNBMD was higher overall in NHANES 2005-2008 than in NHANES III, but between-survey differences varied by age, sex, and race/ethnicity. Although FNBMD differences in several groups were small enough (≤3%) to be attributable to use of different dual-energy X-ray absorptiometry (DXA) systems in the two surveys, variability in size and direction of the differences does not support artifactual differences in DXA methodology as the sole explanation. Several FNBMD determinants (body size, smoking, selected bone-active medications, self-reported health status, calcium intake, and caffeine consumption) changed in a bone-improving direction in older adults, but FNBMD in older non-Hispanic white women remained significantly higher in 2005-2008 even after adjusting for DXA methodology or for the selected bone determinants. CONCLUSION: The likelihood that FNBMD has improved appears strongest for older white women, but the reason for the improvement in this group remains unclear.

Lumbar spine bone mineral density in US adults: demographic patterns and relationship with femur neck skeletal status.

UNLABELLED: This analysis examines lumbar spine bone mineral density (BMD) of US adults from NHANES 2005-2008 by age, sex, and race/ethnicity. Prevalence of low spine BMD and agreement between the prevalence of low BMD at the spine and femur neck in older adults are also assessed. INTRODUCTION: Lumbar spine BMD data from a representative sample of the US population have not been previously available. METHODS: We used data from the National Health and Nutrition Examination Survey 2005-2008 to examine demographic patterns in lumbar spine BMD among US adults age ≥20 years and the prevalence of low lumbar spine BMD in adults age ≥50 years. Agreement between the prevalence of low BMD at the femur neck and spine in older adults was also assessed. Dual-energy X-ray absorptiometry was used to measure lumbar spine and femur neck BMD. World Health Organization definitions were used to categorize skeletal status as normal, osteopenia, or osteoporosis. RESULTS: Compared to non-Hispanic whites, non-Hispanic blacks had higher and Mexican Americans had lower lumbar spine BMD. Lumbar spine BMD declined with age in women, but not in men. Approximately 4.7 million (10%) older US women and 1 million (3%) older men had lumbar spine osteoporosis in 2005-2008. Roughly one third of them differed in skeletal status at the spine and hip but most were normal at one site and osteopenic at the other. Only 3-10%, depending on sex, had osteoporosis at one skeletal site but not at the other skeletal site. Between 76% and 87% with discordant skeletal status had lumbar spine T-scores within 1 unit of the category threshold. CONCLUSIONS: These findings suggest that measuring either the femur neck or the lumbar spine will correctly classify the majority of individuals who present for care as osteoporotic or not.

Hip fracture risk in older US adults by treatment eligibility status based on new National Osteoporosis Foundation guidance.

UNLABELLED: This analysis of National Health and Nutrition Examination Survey III data found a significant risk of incident hip fracture in adults aged 65 years and older who are candidates for treatment to lower fracture risk, according to the new National Osteoporosis Foundation Clinician's Guide. INTRODUCTION: The relationship between treatment eligibility by the new National Osteoporosis Foundation (NOF) Guide to the Prevention and Treatment of Osteoporosis and the risk of subsequent hip fracture is unknown. METHODS: The study sample consisted of 3,208 men and women ages 65 years and older who were examined in the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994), a nationally representative survey. Risk factors used to define treatment eligibility at baseline were measured in NHANES III or were simulated using World Health Organization study cohorts. Incident hip fractures were ascertained using linked mortality and Medicare records that were obtained for NHANES III participants through December 31, 2000. Cox proportional hazards models were used to estimate the relative risk (RR) of hip fracture by treatment eligibility status. RESULTS: The RR for subsequent hip fracture was 4.9 (95% CI 3.30, 7.94) in treatment-eligible vs treatment-ineligible persons. The increased risk for treatment-eligible persons remained statistically significant when examined by sex or age: RR(men) = 5.5 (2.6, 11.4) and RR(women) = 4.3 (2.2, 8.4); RR(65-79 y) = 4.8 (2.6, 8.7) and RR(80+ y) = 4.6 (2.1, 10.1). CONCLUSIONS: Treatment-eligible persons were about five times more likely to experience a subsequent hip fracture than the non-eligible persons. The new NOF guidelines appear to predict future hip fracture risk equally in men as in women, and fracture risk prediction did not appear to diminish with age.

The potential impact of new National Osteoporosis Foundation guidance on treatment patterns.

UNLABELLED: This analysis of National Health and Nutrition Examination Survey III data describes the prevalence of risk factors for osteoporosis and the proportions of men and postmenopausal women age 50 years and older who are candidates for treatment to lower fracture risk, according to the new FRAX-based National Osteoporosis Foundation Clinician's Guide. INTRODUCTION: Little information is available on prevalence of osteoporosis risk factors or proportions of US men and women who are potential candidates for treatment. METHODS: The prevalence of risk factors used in the new National Osteoporosis Foundation (NOF) FRAX-based Guide to the Prevention and Treatment of Osteoporosis was estimated using data from the third National Health and Nutrition Examination Survey (NHANES III). Risk factors not measured in NHANES III were simulated using World Health Organization cohorts. The proportion of US men and postmenopausal women age 50+ years who are treatment candidates by the new NOF Guide were calculated; for non-Hispanic white (NHW) women, the proportion eligible by the new NOF Guide was compared with that based on an earlier NOF Guide. RESULTS: Twenty percent of men and 37% of women were potential candidates for treatment to prevent fractures by the new NOF Guide. Among NHW women, 53% were potential candidates by the previous NOF Guide compared with 41% by the new guide. CONCLUSIONS: One fifth of men and 37% of postmenopausal women are eligible for osteoporosis treatment consideration by the new NOF Guide. However, fewer NHW women are eligible by the new guide than by the previous NOF Guide.

Age, gender, and race/ethnic differences in total body and subregional bone density.

SUMMARY: Total body bone density of adults from National Health and Nutrition Examination Survey (NHANES) 1999-2004 differed as expected for some groups (men>women and blacks>whites) but not others (whites>Mexican Americans). Cross-sectional age patterns in bone mineral density (BMD) of older adults differed at skeletal sites that varied by degree of weight-bearing. INTRODUCTION: Total body dual-energy X-ray absorptiometry (DXA) data offer the opportunity to compare bone density of demographic groups across the entire skeleton. METHODS: The present study uses total body DXA data (Hologic QDR 4500A, Hologic, Bedford MA, USA) from the NHANES 1999-2004 to examine BMD of the total body and selected skeletal subregions in a wide age range of adult men and women from three race/ethnic groups. Total body, lumbar spine, pelvis, right leg, and left arm BMD and lean mass from 13,091 adults aged 20 years and older were used. The subregions were chosen to represent sites with different degrees of weight-bearing. RESULTS: Mean BMD varied in expected ways for some demographic characteristics (men>women and non-Hispanic blacks>non-Hispanic whites) but not others (non-Hispanic whites>Mexican Americans). Differences in age patterns in BMD also emerged for some characteristics (sex) but not others (race/ethnicity). Differences in cross-sectional age patterns in BMD and lean mass by degree of weight-bearing in older adults were observed for the pelvis, leg, and arm. CONCLUSION: This information may be useful for generating hypotheses about age, race, and sex differences in fracture risk in the population.

Impact of increased overweight on the projected prevalence of osteoporosis in older women.

INTRODUCTION: Overweight is increasing worldwide, but particularly in the United States of America. Higher body weight is associated with higher bone density, so our goal was to estimate whether the higher prevalence of overweight is likely to reduce osteoporosis among older women. METHODS: We calculated the prevalence of osteoporosis by weight status in older women using data from the third National Health and Nutrition Examination Survey (NHANES III, 1988-94). We defined overweight as a body mass index (BMI) >or=25 and osteoporosis as a femur neck bone mineral density (BMD) value 2.5 standard deviations or more below the mean of that of young women. To estimate the expected prevalence of osteoporosis, we applied the prevalence of osteoporosis by weight status from NHANES III to the corresponding weight status prevalence from NHANES 1999-2002. RESULTS: Of older women in NHANES 1999-2002, 68% were overweight compared to 62% in NHANES III. Overweight status was significantly related to osteoporosis prevalence (P < 0.001). However, the expected prevalence of osteoporosis in NHANES 1999-2002 was only slightly lower than that seen in NHANES III (16.8% vs 18.1%, respectively). CONCLUSIONS: The increasing prevalence of overweight among older US women appears unlikely to be accompanied by a significant reduction in osteoporosis.

Maternal history of osteoporosis and femur geometry.

Most studies that have examined the role of skeletal factors in the relationship between an individual's family history of fracture or osteoporosis and their fracture risk have focused on bone density. In this study, we expanded the scope of skeletal factors to include geometric properties (subperiosteal width, section modulus, cortical thickness, and buckling ratio) in addition to areal bone mineral density (BMD). We compared these skeletal factors at the femur neck and shaft by self-reported maternal history of osteoporosis (OP HX) from 5334 non-Hispanic whites, ages > or =20 years in the Third National Health and Nutrition Examination Survey (NHANES III, 1988-94). A total of 213 men and 315 women reported a positive OP HX (e.g., their biological mother had sustained a hip fracture after age 50 years or had a physician's diagnosis of osteoporosis). Differences in bone density and geometry by OP HX were examined after adjusting for potential confounding variables. Several bone parameters differed significantly by OP HX in both sexes at the femur neck, but none differed at the femur shaft. At the neck, those with a positive OP HX had values that differed by approximately 3% to 4% (lower for BMD, bone mineral content (BMC), cross-sectional area, and cortical thickness; higher for buckling ratios) from those with a negative OP HX (P < 0.05). The magnitude of these relationships was similar in both sexes, but differences were greater in younger versus older adults. In conclusion, both men and women with a positive maternal history of osteoporosis may be at greater risk of femur neck fracture owing to thinner cortices and lower BMC, which in turn results in potentially greater cortical instability (buckling ratio) at this skeletal site.

Patterns of osteocalcin and bone specific alkaline phosphatase by age, gender, and race or ethnicity.

A variety of biochemical markers of bone turnover that assess bone formation or resorption are now available for research and clinical application. However, our understanding of the usual pattern of these measures over age in the general population is limited. Therefore, values of two bone formation markers, serum osteocalcin (Oc) and bone specific alkaline phosphatase (bone ALP), were compared by age, gender, and race or ethnicity using serum obtained from a subsample of blacks, whites, and Mexican Americans from the third National Health and Nutrition Examination Survey (NHANES). In all racial and ethnic groups, mean values of both serum Oc and bone ALP were lower in women than in men <50 years old. In individuals > or =50 years of age, Oc was significantly higher in women than in men. When analyzed in these two broad age groups, Oc was lower in older black men than in white or Mexican American men, but bone ALP was not different among the groups. In women, Oc levels tended to be lower in the black women than in white or Mexican American women. In contrast, bone ALP tended to be lower in white women than in black or Mexican American women. On the other hand, when analyzed by decade, patterns differed between the two markers in both men and women. In women, both Oc and bone ALP rose postmenopausally. However, bone ALP plateaued in the sixth through eighth decades, whereas Oc levels tended to increase further. In men, Oc was highest in the 20-29 year age group, declined and stabilized, then increased again in the seventh decade. In contrast, mean bone ALP did not differ by decade in men. Our data document differences in levels of circulating Oc and bone ALP by age, gender, and race/ethnicity. The age patterns reflected by the two markers are not concordant and distinctions are most evident in the latter decades. Our findings suggest that the specific osteoblast activity reflected by these markers responds differently to the physiologic changes that occur later in life.

Weight loss from maximum body weight among middle-aged and older white women and the risk of hip fracture: the NHANES I epidemiologic follow-up study.

Although weight loss increases bone loss and hip fracture risk in older women, little is known about the relation between weight loss in middle-aged women and subsequent hip fracture risk. The objective of this study was to determine the association between weight loss from reported maximum body weight in middle-aged and older women and the risk of hip fracture. Data were from a nationally representative sample of 2180 community-dwelling white women aged 50-74 years from the Epidemiologic Follow-up Study of the first National Health and Nutrition Examination Survey (NHEFS). In this prospective cohort study, incident hip fracture was ascertained during 22 years of follow-up. The adjusted relative risks associated with weight loss of 10% or more from maximum body weight were elevated for both middle-aged (RR 2.54; 95% CI 1.10-5.86) and older women (RR 2.04; 95% CI 1.37-3.04). For both ages combined, women in the lowest tertile of body mass index at maximum who lost 10% or more of weight had the highest risk of hip fracture (RR 2.37; 95% CI 1.32-4.27). Weight loss from maximum reported body weight in women aged 50-64 years and 65-74 years increased their risk of hip fracture, especially among those who were relatively thin. Weight loss of 10% or more from maximum weight among both middle-aged and older women is an important indicator of hip fracture risk.

Jogging and bone mineral density in men: results from NHANES III.

OBJECTIVES: This cross-sectional population-based study assessed the association of jogging with femoral bone mineral density (BMD) in men. METHODS: Data are from a nationally representative sample of 4254 men aged 20 to 59 years from the Third National Health and Nutrition Examination Survey (NHANES III). Total femoral BMD was measured by dual energy x-ray absorptiometry. Jogging was self-reported. RESULTS: Jogging (any vs none) was strongly associated with higher BMD in multivariate models (P < .01) for both young and middle-aged men. Men who jogged 9 or more times per month had higher BMD levels than those who jogged only 1 to 8 times per month (P = .01). CONCLUSIONS: Jogging is associated with higher femoral neck BMD in men. Additional large-scale studies that measure all aspects of jogging are warranted.

Does body size account for gender differences in femur bone density and geometry?

The extent to which greater bone strength in men is caused by proportionately greater bone mass versus bigger bone size is not clear, primarily because the larger overall body size of men has made direct comparisons of skeletal measures difficult. We examined gender differences in femur neck (FN) areal bone mineral density (BMD) values collected from 5,623 non-Hispanic whites aged 20+ years in the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) before and after correction for measured height and weight. We supplemented the conventional areal BMD data (Hologic QDR 1000) with measurements of areal BMD and geometric properties (subperiosteal width, section modulus, and cortical thickness) made at narrow "cross-sectional" regions traversing the FN and the proximal shaft using a structural analysis program. Before body size adjustment, men had significantly higher values than women for all variables at the three measurement sites (p < 0.0001). Adjustment for body size reduced the differences between the sexes for all variables but had a greater effect on BMD (1-8% higher in men) than on geometry (5-17% higher in men). When examined by age, the sex discrepancy was significantly greater in the older group for all variables except subperiosteal widths. We conclude that although body size difference may account for most of the areal BMD difference between men and women, male bones are still bigger in ways that suggest greater bone strength. These differences may contribute importantly to lower fracture risk in men.