Hip BMD (hip + bmd)

Distribution by Scientific Domains

Kinds of Hip BMD

  • total hip bmd


  • Selected Abstracts


    Age Trends in Femur Stresses From a Simulated Fall on the Hip Among Men and Women: Evidence of Homeostatic Adaptation Underlying the Decline in Hip BMD

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2006
    Thomas J Beck ScD
    Abstract Age trends in proximal femur stresses were evaluated by simulating a fall on the greater trochanter using femur geometry from hip DXA scans of 5334 white men and women in the NHANES III survey. Expansion of femur outer diameter seems to counter net bone loss so that stresses remain similar across age groups, but stresses are higher in older women than in older men. Introduction: The age decline in hip BMD is caused by both bone loss and expansion of outer diameter that increases the region size over which mass is measured in a DXA scan. Because expansion has an opposing effect on structural strength, it may be a homeostatic adaptation to net bone loss to ensure that load stresses are kept within a narrow range. Materials and Methods: Age trends in femur stresses were evaluated with an engineering beam simulation of a fall on the greater trochanter. Hip geometry was extracted from hip DXA scans using the Hip Structure Analysis (HSA) software on 2613 non-Hispanic white men and 2721 women from the third National Health and Nutrition Examination Survey (NHANES III). Using body weight as load, stresses were computed on the inferior-medial and superior-lateral femur neck at its narrowest point and the medial and lateral shaft 2 cm distal to the midpoint of the lesser trochanter. Stresses and the underlying geometries in men and women >50 years oaf age were compared with those 20,49 years of age. Results: Compared with men <50 years of age, stresses in older men were 6% lower on both surfaces of the shaft, 4% lower on the inferior-medial neck, and not different on the superior-lateral neck. In women >50 years of age, stresses on the proximal shaft and inferior-medial neck remained within 3% of young values but were 13% greater on the superior-lateral neck. Neck stresses in young women were lower on the superior-lateral than the inferior-medial neck, but lateral stress increased to the level on the medial surface in older women. Stresses were higher in women than in men, with a greater gender difference in those >50 years of age. Conclusions: We conclude that femur expansion has a homeostatic effect in men and women that opposes bone loss so that stresses change little with age. Because expansion preserves stresses with progressively less bone mass, the process may reduce structural stability in the femoral neck under fall conditions, especially in the elderly female. [source]


    The relationship between focal erosions and generalized osteoporosis in postmenopausal women with rheumatoid arthritis

    ARTHRITIS & RHEUMATISM, Issue 6 2009
    Daniel H. Solomon
    Objective Among rheumatoid arthritis (RA) patients who have had the disease for 10 years, more than half have focal erosions, and the risk of fracture is doubled. However, there is little information about the potential relationship between focal erosions and bone mineral density (BMD). The aim of this study was to determine whether lower BMD is associated with higher erosion scores among patients with RA. Methods We enrolled 163 postmenopausal women with RA, none of whom were taking osteoporosis medications. Patients underwent dual x-ray absorptiometry at the hip and spine and hand radiography, and completed a questionnaire. The hand radiographs were scored using the Sharp method, and the relationship between BMD and erosions was measured using Spearman's correlation coefficients and adjusted linear regression models. Results Patients had an average disease duration of 13.7 years, and almost all were taking a disease-modifying antirheumatic drug. Sixty-three percent were rheumatoid factor (RF) positive. The median modified Health Assessment Questionnaire score was 0.7, and the average Disease Activity Score in 28 joints was 3.8. The erosion score was significantly correlated with total hip BMD (r = ,0.33, P < 0.0001), but not with lumbar spine BMD (r = ,0.09, P = 0.27). Hip BMD was significantly lower in RF-positive patients versus RF-negative patients (P = 0.02). In multivariable models that included age, body mass index, and cumulative oral glucocorticoid dose, neither total hip BMD nor lumbar spine BMD was significantly associated with focal erosions. Conclusion Our results suggest that hip BMD is associated with focal erosions among postmenopausal women with RA, but that this association disappears after multivariable adjustment. While BMD and erosions may be correlated with bone manifestations of RA, their relationship is complex and influenced by other disease-related factors. [source]


    Zoledronic acid prevents bone loss after allogeneic haemopoietic stem cell transplantation

    INTERNAL MEDICINE JOURNAL, Issue 9 2006
    A. B. D'Souza
    Abstract Allogeneic haemopoietic stem cell transplant (alloHSCT) patients are at increased risk of osteoporosis. Zoledronic acid (ZA) is a potent i.v. bisphosphonate; however, there are few data on ZA use after alloHSCT. The aim of this study is to examine the effect of a single 4 mg ZA infusion in alloHSCT patients with either osteoporosis (T -score < ,2.5) or rapid bone loss post-alloHSCT. An uncontrolled, prospective study of 12 consecutive patients receiving ZA, predominantly within the first year post-HSCT. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the spine and proximal femur pretransplant, pre-ZA and post-ZA. The median annualized percentage change in total hip BMD between the pretransplant scan and the scan immediately before ZA was ,13% (range, ,51 to +3.6%). After ZA treatment, the total hip BMD increased by a median of +3.3% (range, ,20.4 to +14.8%) in 75% of patients. The median annualized percentage change in femoral neck BMD between the pretransplant scan and the scan immediately before ZA was ,13.2% (range, ,40 to +1.0%). Post-ZA, femoral neck BMD increased by a median of +1.4% (range, ,22.2 to +33.6%). Only one patient continued to lose bone from the femoral neck post-ZA infusion. The median annualized percentage change in spinal BMD pretransplant was ,12.5% (range, ,38 to +6.9%). Post-ZA, spinal BMD decreased by a median of ,2.8% (range, ,27.6 to +24.4%). Four patients continued to lose bone from the spine post-ZA. ZA reduces bone loss in most patients after alloHSCT. Our data require confirmation in a larger prospective, randomized study. [source]


    Single-Point Assessment of Warfarin Use and Risk of Osteoporosis in Elderly Men

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 7 2008
    Claudine Woo PhD
    OBJECTIVES: To determine whether warfarin use, assessed at a single point in time, is associated with bone mineral density (BMD), rates of bone loss, and fracture risk in older men. DESIGN: Secondary analysis of data from a prospective cohort study. SETTING: Six U.S. clinical centers. PARTICIPANTS: Five thousand five hundred thirty-three community-dwelling, ambulatory men aged 65 and older with baseline warfarin use data. MEASUREMENTS: Warfarin use was assessed as current use of warfarin at baseline using an electronic medication coding dictionary. BMD was measured at the hip and spine at baseline, and hip BMD was repeated at a follow-up visit 3.4 years later. Self-reported nonspine fractures were centrally adjudicated. RESULTS: At baseline, the average age of the participants was 73.6 ± 5.9, and 321 (5.8%) were taking warfarin. Warfarin users had similar baseline BMD as nonusers (n=5,212) at the hip and spine (total hip 0.966 ± 0.008 vs 0.959 ± 0.002 g/cm2, P=.37; total spine 1.079 ± 0.010 vs 1.074 ± 0.003 g/cm2, P=.64). Of subjects with BMD at both visits, warfarin users (n=150) also had similar annualized bone loss at the total hip as nonusers (n=2,683) (,0.509 ± 0.082 vs ,0.421 ± 0.019%/year, P=.29). During a mean follow-up of 5.1 years, the risk of nonspine fracture was similar in warfarin users and nonusers (adjusted hazard ratio=1.06, 95% confidence interval=0.68,1.65). CONCLUSION: In this cohort of elderly men, current warfarin use was not associated with lower BMD, accelerated bone loss, or higher nonspine fracture risk. [source]


    Longitudinal Study of Changes in Hip Bone Mineral Density in Caucasian and African-American Women

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2005
    Jane A. Cauley DrPH
    Objectives: To determine whether changes in hip bone mineral density (BMD) differ in Caucasian and African American women. Design: Longitudinal study of changes in hip BMD. Setting: Four U.S. clinical centers. Participants: Six thousand seven Caucasian (mean age 73) and 482 African-American (mean age 75) women enrolled in the Study of Osteoporotic Fractures. Measurements: Total hip and femoral neck BMD were measured an average of 3.5 years apart (Caucasian) and 2.0 years apart (African American). Annual absolute and percentage changes in BMD and bone mineral apparent density (BMAD) were calculated. Results: The multivariate adjusted annual percentage change in BMD was greater in Caucasian than African-American women at the total hip (,0.574%/y vs ,0.334%/y) and femoral neck (,0.515%/y vs ,0.203%/y) (both, P<.001). Similar findings were observed for BMAD. The average annualized rate of BMD loss was twice as high in women aged 75 and older as in women younger than 75 in both ethnic groups. The annual percentage loss in femoral neck BMD in nonusers versus hormone therapy users was (,0.57% vs ,0.22%) in Caucasians and (,0.35% vs 0.64%) in African Americans (interaction P=.03). Conclusion: The average rate of hip BMD loss is approximately twice as great in Caucasian as African-American women and increases with age in both groups. The hormonal and biochemical factors that contribute to ethnic differences and the increase in bone loss with advancing age need to be identified. [source]


    Effects of denosumab on bone mineral density and bone turnover in postmenopausal women transitioning from alendronate therapy

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2010
    David L Kendler
    Abstract Patients treated with bisphosphonates for osteoporosis may discontinue or require a switch to other therapies. Denosumab binds to RANKL and is a potent inhibitor of bone resorption that has been shown to increase bone mineral density (BMD) and decrease fracture risk in postmenopausal women with osteoporosis. This was a multicenter, international, randomized, double-blind, double-dummy study in 504 postmenopausal women,,,55 years of age with a BMD T- score of ,2.0 or less and ,4.0 or more who had been receiving alendronate therapy for at least 6 months. Subjects received open-label branded alendronate 70,mg once weekly for 1 month and then were randomly assigned to either continued weekly alendronate therapy or subcutaneous denosumab 60,mg every 6 months and were followed for 12 months. Changes in BMD and biochemical markers of bone turnover were evaluated. In subjects transitioning to denosumab, total hip BMD increased by 1.90% at month 12 compared with a 1.05% increase in subjects continuing on alendronate (p,<,.0001). Significantly greater BMD gains with denosumab compared with alendronate also were achieved at 12 months at the lumbar spine, femoral neck, and 1/3 radius (all p,<,.0125). Median serum CTX levels remained near baseline in the alendronate group and were significantly decreased versus alendronate (p,<,.0001) at all time points with denosumab. Adverse events and serious adverse events were balanced between groups. No clinical hypocalcemic adverse events were reported. Transition to denosumab produced greater increases in BMD at all measured skeletal sites and a greater reduction in bone turnover than did continued alendronate with a similar safety profile in both groups. Copyright © 2010 American Society for Bone and Mineral Research [source]


    Biochemical Markers of Bone Turnover, Hip Bone Loss, and Fracture in Older Men: The MrOS Study,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2009
    Douglas C Bauer
    Abstract We used data from the Osteoporotic Fractures in Men (MrOS) study to test the hypothesis that men with higher levels of bone turnover would have accelerated bone loss and an elevated risk of fracture. MrOS enrolled 5995 subjects >65 yr; hip BMD was measured at baseline and after a mean follow-up of 4.6 yr. Nonspine fractures were documented during a mean follow-up of 5.0 yr. Using fasting serum collected at baseline and stored at ,190°C, bone turnover measurements (type I collagen N-propeptide [PINP]; , C-terminal cross-linked telopeptide of type I collagen [,CTX]; and TRACP5b) were obtained on 384 men with nonspine fracture (including 72 hip fractures) and 947 men selected at random. Among randomly selected men, total hip bone loss was 0.5%/yr among those in the highest quartile of PINP (>44.3 ng/ml) and 0.3%/yr among those in the lower three quartiles (p = 0.01). Fracture risk was elevated among men in the highest quartile of PINP (hip fracture relative hazard = 2.13; 95% CI: 1.23, 3.68; nonspine relative hazard = 1.57, 95% CI: 1.21, 2.05) or ,CTX (hip fracture relative hazard = 1.76, 95 CI: 1.04, 2.98; nonspine relative hazard = 1.29, 95% CI: 0.99, 1.69) but not TRACP5b. Further adjustment for baseline hip BMD eliminated all associations between bone turnover and fracture. We conclude that higher levels of bone turnover are associated with greater hip bone loss in older men, but increased turnover is not independently associated with the risk of hip or nonspine fracture. [source]


    Antifracture Efficacy and Reduction of Mortality in Relation to Timing of the First Dose of Zoledronic Acid After Hip Fracture,,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2009
    Erik Fink Eriksen
    Abstract Annual infusions of zoledronic acid (5 mg) significantly reduced the risk of vertebral, hip, and nonvertebral fractures in a study of postmenopausal women with osteoporosis and significantly reduced clinical fractures and all-cause mortality in another study of women and men who had recently undergone surgical repair of hip fracture. In this analysis, we examined whether timing of the first infusion of zoledronic acid study drug after hip fracture repair influenced the antifracture efficacy and mortality benefit observed in the study. A total of 2127 patients (1065 on active treatment and 1062 on placebo; mean age, 75 yr; 76% women and 24% men) were administered zoledronic acid or placebo within 90 days after surgical repair of an osteoporotic hip fracture and annually thereafter, with a median follow-up time of 1.9 yr. Median time to first dose after the incident hip fracture surgery was ,6 wk. Posthoc analyses were performed by dividing the study population into 2-wk intervals (calculated from time of first infusion in relation to surgical repair) to examine effects on BMD, fracture, and mortality. Analysis by 2-wk intervals showed a significant total hip BMD response and a consistent reduction of overall clinical fractures and mortality in patients receiving the first dose 2-wk or later after surgical repair. Clinical fracture subgroups (vertebral, nonvertebral, and hip) were also reduced, albeit with more variation and 95% CIs crossing 1 at most time points. We concluded that administration of zoledronic acid to patients suffering a low-trauma hip fracture 2 wk or later after surgical repair increases hip BMD, induces significant reductions in the risk of subsequent clinical vertebral, nonvertebral, and hip fractures, and reduces mortality. [source]


    Sequential Treatment of Severe Postmenopausal Osteoporosis After Teriparatide: Final Results of the Randomized, Controlled European Study of Forsteo (EUROFORS),,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2009
    Richard Eastell
    Abstract It is unclear which treatment should be given after stopping teriparatide therapy for severe osteoporosis. In a prospective, randomized, controlled, 2-yr study, we compared BMD effects and clinical safety of three follow-up treatments (anabolic with teriparatide, antiresorptive with raloxifene, or no active treatment) after 1 yr of teriparatide. Postmenopausal women with osteoporosis and a recent fragility fracture received open-label teriparatide (20 ,g/d) for 12 mo before they were randomized (3:1:1) to continue teriparatide (n = 305), switch to raloxifene 60 mg/d (n = 100), or receive no active treatment for the second year (n = 102). All patients received calcium and vitamin D supplementation. Changes in areal BMD from baseline to 24 mo were analyzed using mixed-model repeated measures. Daily teriparatide treatment for 2 yr significantly increased spine BMD by 10.7%. Patients receiving raloxifene in year 2 had no further change in spine BMD from year 1 (change from baseline, 7.9%), whereas patients receiving no active treatment had a BMD decrease of 2.5% in year 2 (change from baseline, +3.8%). At the total hip, BMD increases from baseline at 2 yr were 2.5% with teriparatide, 2.3% with raloxifene, and 0.5% with no active treatment; the respective changes at the femoral neck were 3.5%, 3.1%, and 1.3%. The study had insufficient power to assess antifracture efficacy. In conclusion, BMD increases progressively over 2 yr of teriparatide therapy in women with severe osteoporosis. After discontinuation of teriparatide, raloxifene maintains spine BMD and increases hip BMD. [source]


    Calcifications in the Abdominal Aorta Predict Fractures in Men: MINOS Study,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2008
    Pawel Szulc MD
    In a cohort of 781 men ,50 yr of age followed up for 10 yr, extended calcifications in the abdominal aorta were associated with a 2- to 3-fold increase in the risk of osteoporotic fractures regardless of BMD and falls. Introduction: Cardiovascular disease and osteoporotic fractures are public health problems that frequently coexist. Materials and Methods: We assessed the relation of the severity of aortic calcifications with BMD and the risk of fracture in 781 men ,50 yr of age. During a 10-year follow-up, 66 men sustained incident clinical fractures. Calcifications in the abdominal aorta expressed as an aortic calcification score (ACS) were assessed by a semiquantitative method. BMD was measured at the lumbar spine, hip, whole body, and distal forearm. Results: ACS > 2 was associated with a 2-fold increase in the mortality risk after adjustment for age, weight, smoking, comorbidity, and medications. After adjustment for age, body mass index (BMI), smoking, and comorbidity, men in the highest quartile of ACS (>6) had lower BMD of distal forearm, ultradistal radius, and whole body than men in the lower quartiles. Log-transformed ACS predicted fractures when adjusted for age, BMI, age by BMI interaction, prevalent fractures, BMD, and history of two or more falls (e.g., hip BMD; OR = 1.44; p < 0.02). ACS, BMD at all the skeletal sites, and history of two or more falls were independent predictors of fracture. Men with ACS > 6 had a 2- to 3-fold increased risk of fracture after adjustment for confounding variables (OR = 2.54-3.04; p < 0.005-0.001 according to the site). Conclusions: This long-term prospective study showed that elevated ACS (>6) is a robust and independent risk factor for incident fracture in older men regardless of age, BMI, BMD, prevalent fractures, history of two or more falls, comorbidities, and medications. [source]


    Endogenous Estrogen Levels and the Effects of Ultra-Low-Dose Transdermal Estradiol Therapy on Bone Turnover and BMD in Postmenopausal Women,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2007
    Alison J Huang
    Abstract In a randomized controlled trial of a 0.014 mg/d transdermal estradiol patch, serum bone turnover markers decreased to a greater degree in postmenopausal women with lower versus higher endogenous estradiol levels. This suggests that the protective effects of ultra-low-dose estrogen therapy on the postmenopausal skeletal health may depend critically on women's endogenous estrogen levels before treatment. Introduction: Postmenopausal women with very low or undetectable estradiol levels have lower BMD, increased bone turnover, and increased risk of hip and vertebral fracture. We assessed whether the effects of ultra-low-dose 0.014 mg/d transdermal estradiol (Menostar; Berlex, Montvale, NJ, USA) on bone turnover and BMD are influenced by endogenous estradiol levels. Materials and Methods: We analyzed data from postmenopausal women (mean age, 66 yr) randomized to an 0.014-mg/d transdermal estradiol patch or placebo in the ultra-low-dose transdermal estrogen (ULTRA) trial. The free estradiol index (FEI), calculated as the ratio of total estradiol (by mass spectometry) to sex hormone-binding globulin (SHBG; by immunoradiometric assay) × 100, was used to estimate bioavailable estradiol at baseline. Among the 382 women who adhered to ,80% of study medication, we examined change in serum osteocalcin and bone-specific alkaline phosphatase levels at 12 mo and total hip and lumbar spine BMD at 24 mo in each quintile of FEI. Results: Compared with women in the highest quintile of FEI, those in the lowest quintile of FEI had a 26% greater reduction in bone-specific alkaline phosphatase and 15% greater reduction in osteocalcin in response to ultra-low estradiol treatment (p for trend across quintiles < 0.05). There was a trend toward greater improvement in total hip BMD (p = 0.06) but not spine BMD (p = 0.90) in those with lower versus higher FEI levels. Conclusions: The beneficial effects of ultra-low-dose 0.014-mg/d transdermal estrogen therapy on skeletal health may depend critically on women's endogenous estrogen levels before treatment. [source]


    Meta-Analysis of Genome-Wide Scans Provides Evidence for Sex- and Site-Specific Regulation of Bone Mass,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2007
    John PA Ioannidis
    Abstract Several genome-wide scans have been performed to detect loci that regulate BMD, but these have yielded inconsistent results, with limited replication of linkage peaks in different studies. In an effort to improve statistical power for detection of these loci, we performed a meta-analysis of genome-wide scans in which spine or hip BMD were studied. Evidence was gained to suggest that several chromosomal loci regulate BMD in a site-specific and sex-specific manner. Introduction: BMD is a heritable trait and an important predictor of osteoporotic fracture risk. Several genome-wide scans have been performed in an attempt to detect loci that regulate BMD, but there has been limited replication of linkage peaks between studies. In an attempt to resolve these inconsistencies, we conducted a collaborative meta-analysis of genome-wide linkage scans in which femoral neck BMD (FN-BMD) or lumbar spine BMD (LS-BMD) had been studied. Materials and Methods: Data were accumulated from nine genome-wide scans involving 11,842 subjects. Data were analyzed separately for LS-BMD and FN-BMD and by sex. For each study, genomic bins of 30 cM were defined and ranked according to the maximum LOD score they contained. While various densitometers were used in different studies, the ranking approach that we used means that the results are not confounded by the fact that different measurement devices were used. Significance for high average rank and heterogeneity was obtained through Monte Carlo testing. Results: For LS-BMD, the quantitative trait locus (QTL) with greatest significance was on chromosome 1p13.3-q23.3 (p = 0.004), but this exhibited high heterogeneity and the effect was specific for women. Other significant LS-BMD QTLs were on chromosomes 12q24.31-qter, 3p25.3-p22.1, 11p12-q13.3, and 1q32-q42.3, including one on 18p11-q12.3 that had not been detected by individual studies. For FN-BMD, the strongest QTL was on chromosome 9q31.1-q33.3 (p = 0.002). Other significant QTLs were identified on chromosomes 17p12-q21.33, 14q13.1-q24.1, 9q21.32-q31.1, and 5q14.3-q23.2. There was no correlation in average ranks of bins between men and women and the loci that regulated BMD in men and women and at different sites were largely distinct. Conclusions: This large-scale meta-analysis provided evidence for replication of several QTLs identified in previous studies and also identified a QTL on chromosome 18p11-q12.3, which had not been detected by individual studies. However, despite the large sample size, none of the individual loci identified reached genome-wide significance. [source]


    Large-Scale Genome-Wide Linkage Analysis for Loci Linked to BMD at Different Skeletal Sites in Extreme Selected Sibships,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2007
    Yi-Hsiang Hsu
    Abstract Few genome-wide linkage studies of osteoporosis have been conducted in the Asian population. We performed a genome-wide scan involving 3093 adult siblings with at least one sib-pair extremely concordant or discordant for hip BMD. Our results indicated four genome-wide significant QTLs for BMD. In comparison with 12 previous reported linkage studies, we reveal novel linkage regions that have reaching global significance. Introduction: The genetic basis for osteoporosis has been firmly established, but efforts to identify genes associated with this complex trait have been incomplete, especially in Asian populations. The purpose of this study was to identify quantitative trait loci (QTLs) for BMD in a Chinese population. Materials and Methods: We performed a genome-wide scan involving 3093 siblings 25,64 years of age from 941 families, with at least one sib-pair extreme concordant or discordant for total hip BMD from a large community-based cohort (n = 23,327) in Anhui, China. Linkage analysis was performed on BMD residuals adjusted for age, height, weight, occupation, cigarette smoking, physical activity, and alcohol consumption using the revised Haseman-Elston regression-based linkage model. Results: Our results revealed significant QTLs on chromosome 7p21.2 for femoral neck BMD (LOD = 3.68) and on chromosome 2q24.3 for total hip BMD (LOD = 3.65). Suggestive linkage regions were found to overlap among different skeletal sites on chromosomes 2q, 7p, and 16q. Sex-specific linkage analysis further revealed a significant QTL for lumbar spine BMD on chromosome 13q21.1 (LOD = 3.62) in women only. When performing multivariate linkage analysis by combining BMDs at four skeletal sites (i.e., whole body, total hip, femoral neck, and lumbar spine BMD), an additional significant QTL was found at chromosome 5q21.2 (LOD = 4.56). None of these significant QTLs found in our study overlapped with major QTLs reported by other studies. Conclusions: This study reveals four novel QTLs in a Chinese population and suggests that BMD at different skeletal sites may also share common genetic determinants. [source]


    Age Trends in Femur Stresses From a Simulated Fall on the Hip Among Men and Women: Evidence of Homeostatic Adaptation Underlying the Decline in Hip BMD

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2006
    Thomas J Beck ScD
    Abstract Age trends in proximal femur stresses were evaluated by simulating a fall on the greater trochanter using femur geometry from hip DXA scans of 5334 white men and women in the NHANES III survey. Expansion of femur outer diameter seems to counter net bone loss so that stresses remain similar across age groups, but stresses are higher in older women than in older men. Introduction: The age decline in hip BMD is caused by both bone loss and expansion of outer diameter that increases the region size over which mass is measured in a DXA scan. Because expansion has an opposing effect on structural strength, it may be a homeostatic adaptation to net bone loss to ensure that load stresses are kept within a narrow range. Materials and Methods: Age trends in femur stresses were evaluated with an engineering beam simulation of a fall on the greater trochanter. Hip geometry was extracted from hip DXA scans using the Hip Structure Analysis (HSA) software on 2613 non-Hispanic white men and 2721 women from the third National Health and Nutrition Examination Survey (NHANES III). Using body weight as load, stresses were computed on the inferior-medial and superior-lateral femur neck at its narrowest point and the medial and lateral shaft 2 cm distal to the midpoint of the lesser trochanter. Stresses and the underlying geometries in men and women >50 years oaf age were compared with those 20,49 years of age. Results: Compared with men <50 years of age, stresses in older men were 6% lower on both surfaces of the shaft, 4% lower on the inferior-medial neck, and not different on the superior-lateral neck. In women >50 years of age, stresses on the proximal shaft and inferior-medial neck remained within 3% of young values but were 13% greater on the superior-lateral neck. Neck stresses in young women were lower on the superior-lateral than the inferior-medial neck, but lateral stress increased to the level on the medial surface in older women. Stresses were higher in women than in men, with a greater gender difference in those >50 years of age. Conclusions: We conclude that femur expansion has a homeostatic effect in men and women that opposes bone loss so that stresses change little with age. Because expansion preserves stresses with progressively less bone mass, the process may reduce structural stability in the femoral neck under fall conditions, especially in the elderly female. [source]


    Hyperkyphotic Posture and Risk of Future Osteoporotic Fractures: The Rancho Bernardo Study,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2006
    Mei-Hua Huang
    Abstract It is unknown whether kyphosis of the thoracic spine is an independent risk factor for future osteoporotic fractures. In 596 community-dwelling women, we found that with increasing kyphosis, there was a significant trend of increasing fracture risk that was independent of previous history of fractures or BMD. Introduction: It is unknown whether kyphosis of the thoracic spine is an independent risk factor for future osteoporotic fractures. Materials and Methods: We conducted a prospective cohort study of 596 community-dwelling women, 47-92 years of age. Between 1988 and 1991, BMD of the hip and spine and kyphosis were measured. Kyphosis was measured by counting the number of 1.7-cm blocks necessary to place under the occiput so participants could lie flat without neck hyperextension. New fractures were reported over an average follow-up of 4 years. Results: Using a cut-off of at least one block, 18% of the participants had hyperkyphotic posture (range, one to nine blocks). There were 107 women who reported at least one new fracture (hip, spine, wrist, clavicle, shoulder, arm, hand, rib, pelvis, leg, or ankle). In logistic regression analyses, older women with hyperkyphotic posture (defined as at least one block) had a 1.7-fold increased risk of having a future fracture independent of age, prior fracture, and spine or hip BMD (95% CI: 1.00-2.97; p = 0.049). There was a significant trend of increasing fracture risk with increasing number of blocks, with ORs ranging from 1.5 to 2.6 as the number of blocks increased from one to at least three blocks compared with those with zero blocks (trend p = 0.03; models adjusted for age, baseline fracture, spine or hip BMD). Stratification by baseline fracture status and controlling for other possible confounders or past year falls did not change the results. Conclusions: Whereas hyperkyphosis may often result from vertebral fractures, our study findings suggest that hyperkyphotic posture itself may be an important risk factor for future fractures, independent of low BMD or fracture history. [source]


    Monthly Oral Ibandronate Therapy in Postmenopausal Osteoporosis: 1-Year Results From the MOBILE Study

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2005
    Paul D Miller MD
    Abstract Once-monthly (50/50, 100, and 150 mg) and daily (2.5 mg; 3-year vertebral fracture risk reduction: 52%) oral ibandronate regimens were compared in 1609 women with postmenopausal osteoporosis. At least equivalent efficacy and similar safety and tolerability were shown after 1 year. Introduction: Suboptimal adherence to daily and weekly oral bisphosphonates can potentially compromise therapeutic outcomes in postmenopausal osteoporosis. Although yet to be prospectively shown in osteoporosis, evidence from randomized clinical trials in several other chronic conditions shows that reducing dosing frequency enhances therapeutic adherence. Ibandronate is a new and potent bisphosphonate with antifracture efficacy proven for daily administration and also intermittent administration with a dose-free interval of >2 months. This report presents comparative data on the efficacy and safety of monthly and daily oral ibandronate regimens. Materials and Methods: MOBILE is a 2-year, randomized, double-blind, phase III, noninferiority trial. A total of 1609 women with postmenopausal osteoporosis were assigned to one of four oral ibandronate regimens: 2.5 mg daily, 50 mg/50 mg monthly (single doses, consecutive days), 100 mg monthly, or 150 mg monthly. Results: After 1 year, lumbar spine BMD increased by 3.9%, 4.3%, 4.1%, and 4.9% in the 2.5, 50 /50, 100, and 150 mg arms, respectively. All monthly regimens were proven noninferior, and the 150 mg regimen superior, to the daily regimen. All monthly regimens produced similar hip BMD gains, which were larger than those with the daily regimen. All regimens similarly decreased serum levels of C-telopeptide, a biochemical marker of bone resorption. Compared with the daily regimen, a significantly larger proportion of women receiving the 100 and 150 mg monthly regimens achieved predefined threshold levels for percent change from baseline in lumbar spine (6%) or total hip BMD (3%). All regimens were similarly well tolerated. Conclusions: Monthly ibandronate is at least as effective and well tolerated as the currently approved daily ibandronate regimen in postmenopausal osteoporosis. [source]


    Effect of 6-Month Whole Body Vibration Training on Hip Density, Muscle Strength, and Postural Control in Postmenopausal Women: A Randomized Controlled Pilot Study,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2004
    Sabine MP Verschueren
    Abstract High-frequency mechanical strain seems to stimulate bone strength in animals. In this randomized controlled trial, hip BMD was measured in postmenopausal women after a 24-week whole body vibration (WBV) training program. Vibration training significantly increased BMD of the hip. These findings suggest that WBV training might be useful in the prevention of osteoporosis. Introduction: High-frequency mechanical strain has been shown to stimulate bone strength in different animal models. However, the effects of vibration exercise on the human skeleton have rarely been studied. Particularly in postmenopausal women,who are most at risk of developing osteoporosis,randomized controlled data on the safety and efficacy of vibration loading are lacking. The aim of this randomized controlled trial was to assess the musculoskeletal effects of high-frequency loading by means of whole body vibration (WBV) in postmenopausal women. Materials and Methods: Seventy volunteers (age, 58,74 years) were randomly assigned to a whole body vibration training group (WBV, n = 25), a resistance training group (RES, n = 22), or a control group (CON, n = 23). The WBV group and the RES group trained three times weekly for 24 weeks. The WBV group performed static and dynamic knee-extensor exercises on a vibration platform (35,40 Hz, 2.28,5.09g), which mechanically loaded the bone and evoked reflexive muscle contractions. The RES group trained knee extensors by dynamic leg press and leg extension exercises, increasing from low (20 RM) to high (8 RM) resistance. The CON group did not participate in any training. Hip bone density was measured using DXA at baseline and after the 6-month intervention. Isometric and dynamic strength were measured by means of a motor-driven dynamometer. Data were analyzed by means of repeated measures ANOVA. Results: No vibration-related side effects were observed. Vibration training improved isometric and dynamic muscle strength (+15% and + 16%, respectively; p < 0.01) and also significantly increased BMD of the hip (+0.93%, p < 0.05). No changes in hip BMD were observed in women participating in resistance training or age-matched controls (,0.60% and ,0.62%, respectively; not significant). Serum markers of bone turnover did not change in any of the groups. Conclusion: These findings suggest that WBV training may be a feasible and effective way to modify well-recognized risk factors for falls and fractures in older women and support the need for further human studies. [source]


    Quantitative Trait Loci on Chromosomes 2p, 4p, and 13q Influence Bone Mineral Density of the Forearm and Hip in Mexican Americans,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2003
    Candace M Kammerer
    Abstract We performed a genome scan using BMD data of the forearm and hip on 664 individuals in 29 Mexican-American families. We obtained evidence for QTL on chromosome 4p, affecting forearm BMD overall, and on chromosomes 2p and 13q, affecting hip BMD in men. Introduction: The San Antonio Family Osteoporosis Study (SAFOS) was designed to identify genes and environmental factors that influence bone mineral density (BMD) using data from large Mexican-American families. Materials and Methods: We performed a genome-wide linkage analysis using 416 highly polymorphic microsatellite markers spaced approximately 9.5 cM apart to locate and identify quantitative trait loci (QTL) that affect BMD of the forearm and hip. Multipoint variance components linkage analyses were done using data on all 664 subjects, as well as two subgroups of 259 men and 261 premenopausal women, from 29 families for which genotypic and phenotypic data were available. Results: We obtained significant evidence for a QTL affecting forearm (radius midpoint) BMD in men and women combined on chromosome 4p near D4S2639 (maximum LOD = 4.33, genomic p = 0.006) and suggestive evidence for a QTL on chromosome 12q near locus D12S2070 (maximum conditional LOD = 2.35). We found suggestive evidence for a QTL influencing trochanter BMD on chromosome 6 (maximum LOD = 2.27), but no evidence for QTL affecting the femoral neck in men and women combined. In men, we obtained evidence for QTL affecting neck and trochanter BMD on chromosomes 2p near D2S1780 (maximum LOD = 3.98, genomic p = 0.013) and 13q near D13S788 (maximum LOD = 3.46, genomic p = 0.039), respectively. We found no evidence for QTL affecting forearm or hip BMD in premenopausal women. Conclusion: These results provide strong evidence that a QTL on chromosome 4p affects radius BMD in Mexican-American men and women, as well as evidence that QTL on chromosomes 2p and 13q affect hip BMD in men. Our results are consistent with some reports in humans and mice. [source]


    Fractal Analysis of Radiographic Trabecular Bone Texture and Bone Mineral Density: Two Complementary Parameters Related to Osteoporotic Fractures

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2001
    C. L. Benhamou
    Abstract Trabecular bone microarchitecture and bone mineral density (BMD) are two main factors related to osteoporotic fractures. Currently, however, microarchitecture is not evaluated. We have developed and validated a trabecular bone texture analysis from radiographic images. The objective was to determine if the fractal analysis of texture was able to distinguish osteoporotic fracture groups from control groups, either in vertebrae, hip, or wrist fractures, and to determine if this indicator and BMD were independent and complementary. In this cross-sectional unicenter case-control population study in postmenopausal women, 107 fracture cases were enrolled and age-matched with 197 control cases. This population comprised 40 vertebral fractures (with 70 controls), 30 hip fractures (55 controls), and 37 wrist fractures (62 controls). Hip and lumbar spine BMD were measured by double-energy X-ray absorptiometry. Fractal analysis of texture was performed on calcaneus radiographs and the result was expressed as the H parameter (H = 2-fractal dimension). The H parameter showed a lower value (0.679 ± 0.053 SD) in fracture cases versus control cases (0.696 ± 0.030; p = 0.007), the statistical significance persisting after adjustment for age and for lumbar spine (LS) or hip BMD. This result was confirmed in vertebral fractures (p = 0.0001) and hip fractures (p = 0.003) but not wrist fractures (p = 0.07). We determined the threshold between high and low H values and then the odds ratios (OR) of fracture for low H for BMD , ,2.5 SD in T score and for the combinations of both parameters. The OR of fracture for low H was 1.6 (95% CI, 1.1,2.6). For LS BMD , ,2.5 SD the OR of 6.1 (3.4,10.8) shifted to 9.0 (4.0,20.4) when we added low H and for hip BMD it shifted from 5.6 (3.3,9.4) to 8.1 (4.0,16.8). In vertebral, hip, and wrist fracture cases the results were also significant. These data have shown that the fractal analysis of texture on calcaneus radiographs can distinguish osteoporotic fracture groups from control groups. This analysis and BMD provide independent and complementary information. These data suggest that we can improve the fracture risk evaluation by adding information related to microarchitecture, derived from analysis of conventional radiographic images. [source]


    Fitness, fatness and activity as predictors of bone mineral density in older persons

    JOURNAL OF INTERNAL MEDICINE, Issue 5 2002
    K. J. Stewart
    Abstract. Stewart KJ, DeRegis JR, Turner KL, Bacher AC, Sung J, Hees PS, Tayback M, Ouyang P (Johns Hopkins Bayview Medical Center, Johns Hopkins University, School of Medicine, Baltimore, MD, USA). Fitness, fatness, and activity as predictors of bone mineral density in older persons. J Intern Med 2002; 252: 381,388. Objectives. To determine relationships of bone mineral density (BMD) with fitness, physical activity, and body composition and fat distribution. Design. Cross-sectional. Setting. General Clinical Research Center, Johns Hopkins Bayview Medical Center, Baltimore, Maryland. Subjects. Men (n = 38) and women (n = 46), aged 55,75 years with high normal blood pressure or mild hypertension but otherwise healthy. Methods. Aerobic fitness (oxygen uptake) on a treadmill, muscle strength by one-repetition maximum, activity by questionnaire, abdominal obesity by magnetic resonance imaging; anthropometrics, and body composition by dual energy X-ray absorptiometry (DXA) which measured total fat and lean mass, and BMD for the total skeleton, lumbar spine (L1,L4) and total hip. Results. Aerobic fitness did not correlate with BMD. Using multivariate analysis to ascertain independent contributions to the variance in BMD, in women, with adjustment for hormone replacement therapy (HRT), total skeleton BMD was independently related to muscle strength and abdominal total fat; total hip BMD to body weight; lumbar spine BMD to abdominal total fat. HRT also influenced BMD in the lumbar spine. In men, lumbar spine BMD was independently related to abdominal total fat physical activity and total hip BMD related to lower body strength. P < 0.05 for all of these correlations. Conclusions. Abdominal obesity and muscle strength emerge as predominant correlates of BMD in older persons with stronger relationships seen in women. Body weight and HRT also explained portions of the variance in BMD in women. Whether abdominal obesity is simply a marker for general obesity or has independent protective effects on bone is yet to be determined. [source]


    The relationship between focal erosions and generalized osteoporosis in postmenopausal women with rheumatoid arthritis

    ARTHRITIS & RHEUMATISM, Issue 6 2009
    Daniel H. Solomon
    Objective Among rheumatoid arthritis (RA) patients who have had the disease for 10 years, more than half have focal erosions, and the risk of fracture is doubled. However, there is little information about the potential relationship between focal erosions and bone mineral density (BMD). The aim of this study was to determine whether lower BMD is associated with higher erosion scores among patients with RA. Methods We enrolled 163 postmenopausal women with RA, none of whom were taking osteoporosis medications. Patients underwent dual x-ray absorptiometry at the hip and spine and hand radiography, and completed a questionnaire. The hand radiographs were scored using the Sharp method, and the relationship between BMD and erosions was measured using Spearman's correlation coefficients and adjusted linear regression models. Results Patients had an average disease duration of 13.7 years, and almost all were taking a disease-modifying antirheumatic drug. Sixty-three percent were rheumatoid factor (RF) positive. The median modified Health Assessment Questionnaire score was 0.7, and the average Disease Activity Score in 28 joints was 3.8. The erosion score was significantly correlated with total hip BMD (r = ,0.33, P < 0.0001), but not with lumbar spine BMD (r = ,0.09, P = 0.27). Hip BMD was significantly lower in RF-positive patients versus RF-negative patients (P = 0.02). In multivariable models that included age, body mass index, and cumulative oral glucocorticoid dose, neither total hip BMD nor lumbar spine BMD was significantly associated with focal erosions. Conclusion Our results suggest that hip BMD is associated with focal erosions among postmenopausal women with RA, but that this association disappears after multivariable adjustment. While BMD and erosions may be correlated with bone manifestations of RA, their relationship is complex and influenced by other disease-related factors. [source]


    Heel ultrasonography is not a good screening tool for bone loss after kidney and pancreas transplantation

    CLINICAL TRANSPLANTATION, Issue 5 2004
    Lynn R Mack-Shipman
    Abstract:, Background:, Solid organ transplant recipients, particularly simultaneous pancreas kidney recipients, are at high fracture risk. We tested whether quantitative ultrasonography (QUS) of the heel predicts bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) in solid organ transplant recipients. Methods:, Thirty-eight transplant recipients (22 Female/16 Male) were studied. Spine and hip BMD was measured with a Hologic DXA scanner. ,Stiffness' of the heel was measured with a Lunar Ultrasound densitometer and compared with BMD by DXA. Contributing factors to bone loss were also assessed. Results:, Mean age was 43.1 ± 1.3 yr. Simultaneous pancreas-kidney, kidney, and pancreas alone transplant recipients were assessed. Mean time post-transplantation was 3.0 ± 0.6 yr. Mean DXA spine T-score was ,1.15 ± 0.22 (mean ± SEM) and hip T-score was ,1.22 ± 0.20. There was no difference in mean T-score between women and men at the hip or spine. Mean right heel stiffness T-score was ,0.97 ± 0.25. There was no correlation between QUS and DXA at either the hip or spine in women or men. QUS had a false negative rate for identifying osteopenia or osteoporosis of 17% compared with DXA. The false positive rate for identifying osteopenia was 61%. Conclusions:, The QUS is an unacceptable tool for identifying those at risk for bone loss after kidney or pancreas transplantation. [source]