Association between change in BMD and fragility fracture in women and men

Correlation of sex hormone levels with orthodontic tooth movement in the maxilla: a prospective cohort study

BACKGROUND

Sex hormones secreted during the menstrual cycle and the application of orthodontic forces to teeth can affect the metabolism of periodontal ligaments. This study aimed to determine whether there are any differences in orthodontic tooth displacement during the menstrual cycle and when using hormonal contraceptives and whether the amount of female sex hormones influences the efficiency of tooth displacement.

METHODS

A total of 120 women aged between 20 and 30 years with Angle Class II requiring transpalatal arch (TPA) to derotate teeth 16 and 26 were included in this study. The participants were divided into two groups: group A, which included women with regular menstruation, and control group B, which included women taking monophasic combined oral contraceptives. Group A was divided into subgroups according to the moment of TPA activation: menstruation (A1), ovulation phase (A2), and luteal phase (A3) (examination I). On intraoral scans, measurement points were marked on the proximal mesial cusps of teeth 16 and 26, and the intermolar distance (M1) was determined. The change in the position of the measurement points 6 weeks after activation (examination II) made it possible to determine the derotating extent of teeth 16 (O16) and 26 (O26) and the widening of the intermolar distance (M2-M1). In examinations I and II, tooth mobility in the alveoli was assessed using Periotest based on the periotest values (PTV) PTV1 and PTV2, respectively.

RESULTS

A significant difference in all parameters was observed among groups A1, A2, and A3 (P < 0.001). Group A3 showed the highest values of parameters O16, O26, and M2-M1, and group A2 showed the lowest values, which did not differ from the control group (P = 0.64). PTV2 and PTV1 were the highest in group A3 and the lowest in groups A1 and B. Intergroup differences were statistically significant (P < 0.001).

CONCLUSIONS

With the quantification of changes in tooth mobility in the alveoli during the menstrual cycle in women undergoing orthodontic treatment, it was possible to determine that female sex hormones affect the effectiveness of orthodontic treatment, and the optimal moment for TPA activation is the luteal phase of the menstrual cycle.

Weight-adjusted waist index is a potential early predictor of degraded bone microarchitecture: A cross-sectional study of the national health and nutrition examination survey 2007-2008

PURPOSE

This study aimed to investigate the association between weight-adjusted waist index (WWI) and trabecular bone score (TBS) and to assess the ability of WWI to identify individuals with degraded bone microarchitecture (DBMA).

METHODS

This cross-sectional study included participants aged 20 and older from the National Health and Nutrition Examination Survey. Furthermore, WWI was calculated by waist circumference and body weight. In addition, linear regression models were employed to investigate the association between WWI and TBS, while logistic regression models were employed to determine the association between WWI and the risk of DBMA. Finally, the performance of WWI in identifying individuals with DBMA was using the receiver operating characteristic (ROC) curves with area under the ROC curve.

RESULTS

A total of 4,179 participants with a mean age of 49.90 years were included in the final analysis. WWI was negatively associated with TBS and positively associated with an increased risk of DBMA. Furthermore, the associations between WWI and TBS, as well as DBMA risk, were stable regardless of stratification by age, sex, race, or body mass index (BMI). Moreover, WWI achieved good performances in identifying individuals with DBMA or low TBS. In addition, the combination of WWI and BMI showed better performances in identifying individuals with DBMA or low TBS than WWI or BMI alone.

CONCLUSION

WWI established a negative association with TBS and a positive association with the risk of DBMA. Clinicians should be alert to the potential risk of DBMA among individuals with high WWI. Moreover, WWI, alone or in combination with BMI, has the potential to serve as an early screening strategy in identifying individuals with DBMA.

Effects of vitamin D3, omega-3 s and a simple strength training exercise program on bone health: the DO-HEALTH randomized controlled trial

INTRODUCTION

Evidence on the effects of Vitamin D, omega-3 s and exercise on aBMD in healthy older adults is limited. We examined whether vitamin D3, omega-3 s, or a simple home-based exercise program (SHEP), alone or in combination, over three years, improve lumbar spine (LS), femoral neck (FN) or total hip (TH) aBMD assessed by DXA.

METHODS

aBMD was a secondary outcome in DO-HEALTH, a 3-year, multicenter, double-blind, randomized 2 × 2 × 2 factorial design trial in generally healthy older adults age ≥ 70 years. The study interventions were vitamin D3 (2000IU/d), omega-3 s (1 g/d), and SHEP (3 × 30 min/wk), applied alone or in combination in 8 treatment arms. Mixed effect models were used adjusting for age, sex, BMI, prior fall, study site and baseline level of the outcome. Main effects were assessed in the absence of an interaction between the interventions. Subgroup analyses by sex, physical activity level, dietary calcium intake, serum 25(OH)D levels, and fracture history were conducted.

RESULTS

DXA scans were available for 1493 participants (mean age 75 years; 80.4% were physically active, 44% had 25(OH)D levels <20 ng/ml). At the LS and FN sites, none of the treatments showed a benefit. At the TH, vitamin D vs. no vitamin D treatment showed a significant benefit across 3 years (difference in adjusted means [AM]: 0.0035 [95% CI 0.0011, 0.0059] g/cm2). Furthermore, there was a benefit for vitamin D vs. no vitamin D treatment on LS aBMD in the male subgroup of (interaction P = 0.003; ∆AM: 0.0070 [95% CI 0.0007, 0.0132] g/cm2).

CONCLUSIONS

Omega-3 and SHEP had no benefit on aBMD in healthy, active and largely vitamin D replete older adults. Our study suggests a small benefit of 2000 IU vitamin D daily on TH aBMD overall and LS aBMD among men, however, effect sizes were very modest and the clinical impact of these findings is unclear.

Follow-up Bone Mineral Density Testing: 2023 Official Positions of the International Society for Clinical Densitometry

Dual-energy X-ray absorptiometry (DXA) is the gold standard method for measuring bone mineral density (BMD) which is most strongly associated with fracture risk. BMD is therefore the basis for the World Health Organization's densitometric definition of osteoporosis. The International Society for Clinical Densitometry (ISCD) promotes best densitometry practices and its official positions reflect critical review of current evidence by domain experts. This document reports new official positions regarding follow-up DXA examinations based on a systematic review of literature published through December 2022. Adoption of official positions requires consensus agreement from an expert panel following a modified RAND protocol. Unless explicitly altered by the new position statements, prior ISCD official positions remain in force. This update reflects increased consideration of the clinical context prompting repeat examination. Follow-up DXA should be performed with pre-defined objectives when the results would have an impact on patient management. Testing intervals should be individualized according to the patient's age, sex, fracture risk and treatment history. Incident fractures and therapeutic approach are key considerations. Appropriately ordered and interpreted follow-up DXA examinations support diagnostic and therapeutic decision making, thereby contributing to excellent clinical care. Future research should address the complementary roles of clinical findings, imaging and laboratory testing to guide management.

The Potential Therapeutic Effects of Platelet-Derived Biomaterials on Osteoporosis: A Comprehensive Review of Current Evidence

Osteoporosis is a chronic multifactorial condition that affects the skeletal system, leading to the deterioration of bone microstructure and an increased risk of bone fracture. Platelet-derived biomaterials (PDBs), so-called platelet concentrates, such as platelet-rich plasma (PRP) and platelet-rich fibrin (PRF), have shown potential for improving bone healing by addressing microstructural impairment. While the administration of platelet concentrates has yielded positive results in bone regeneration, the optimal method for its administration in the clinical setting is still debatable. This comprehensive review aims to explore the systemic and local use of PRP/PRF for treating various bone defects and acute fractures in patients with osteoporosis. Furthermore, combining PRP/PRF with stem cells or osteoinductive and osteoconductive biomaterials has shown promise in restoring bone microstructural properties, treating bony defects, and improving implant osseointegration in osteoporotic animal models. Here, reviewing the results of in vitro and in vivo studies, this comprehensive evaluation provides a detailed mechanism for how platelet concentrates may support the healing process of osteoporotic bone fractures.

Association of follicle-stimulating hormone with bone turnover markers and bone mineral density in Chinese women across the menopausal transition

BACKGROUND

Elevated follicle-stimulating hormone (FSH) is associated with an increased risk of postmenopausal osteoporosis. This study investigated the association of serum FSH with bone turnover markers (BTMs) and bone mineral density (BMD) in healthy women undergoing menopausal transition.

METHODS

A total of 487 healthy women (age 35-65 years, 50 ± 8.5 years) were enrolled in this study. Serum FSH, BTMs, and BMD at lumbar spine and total hip were measured in these subjects.

RESULTS

Follicle-stimulating hormone was positively correlated with various BTMs (r = 0.339-0.583, all p < 0.001) and negatively correlated with lumbar spine and total hip BMD (r = -0.629 and -0.514, all p < 0.001). After adjusting for age and body mass index, the partial correlation coefficients of FSH with BTMs and BMD remained significant. Estimating from the regression equation, for every 10 IU/L increase in serum FSH, BTMs increased by 0.38-3.6 units, and BMD decreased by 0.03-0.05 g/cm2 , respectively. Multiple linear regression analysis showed that FSH was a positive factor for serum bone-specific alkaline phosphatase, osteocalcin, and N-telopeptide of collagen type 1 (β = 0.188-0.403, all p < 0.001), and a negative factor for lumbar spine BMD and serum C-telopeptide of collagen type 1 (β = -0.629 and -0.183, all p < 0.001).

CONCLUSIONS

This study suggests that serum FSH levels are an independent risk factor for BTMs and BMD in menopause-transitioning women, particularly for serum BAP and lumbar spine BMD.

Increased Imminent Fracture Risk in Liver Transplant Recipients Despite Bisphosphonate Therapy

BACKGROUND

Bone loss is significant after orthotopic liver transplant (OLT) and is associated with increased fracture risk and decreased quality of life. In post-transplant fracture prevention, the cornerstone of therapeutic management is bisphosphonates.

METHODS

We conducted a retrospective study in a cohort of 155 OLT recipients who received a bisphosphonate prescription at hospital discharge between 2012 and 2016 to investigate post-OLT fragility fracture incidence and predictive risk factors.

RESULTS

Before OLT, 14 patients presented a T score < -2.5 SD, and 23 patients (14.8%) had a history of fracture. During follow-up, the cumulative incidence of fractures on bisphosphonates (99.4% risedronate/alendronate) was 9.7% at 12 months and 13.1% at 24 months. The median time to first fragility fracture was 10 months (IQR, 3-22 months) and thus within the first 2 years of follow-up. Predictive factors of fragility fractures in multivariate Cox regression analyses included age 60 years or older (hazard ratio [HR], 2.61; 95% CI, 1.14-6.01; P = .02), post-transplant diabetes mellitus (HR, 3.82; 95% CI, 1.55-9.44; P = .004), and cholestatic disease (HR, 5.93; 95% CI, 2.30-15.26; P = .0002). Additionally, the female sex was associated with a strong trend toward increased fracture risk in univariate analysis (HR, 2.27; 95% CI, 1.00-5.15; P = .05), as well as a post-transplant absolute decrease in bone mineral density at the femoral neck and total hip (P = .08).

CONCLUSIONS

This real-world study reports a high incidence of fractures post-OLT despite bisphosphonate therapy. Age 60 years or older, post-transplant diabetes mellitus, cholestatic disease, female sex, and femoral neck and/or total hip bone mineral density loss contribute to increased imminent fracture risk in liver transplant recipients.

Cytotoxic chemotherapy is associated with decreased bone mineral density in postmenopausal women with early and locally advanced breast cancer

PURPOSE

The burden and mechanisms of endocrine therapy-related bone loss have been studied in detail. However, there is limited data regarding cytotoxic chemotherapy's impact on bone health. There are no definitive guidelines for bone mineral density (BMD) monitoring and treatment with bone-modifying agents during cytotoxic chemotherapy. The study's primary objective was to evaluate the changes in BMD and fracture risk assessment tool (FRAX) scores among breast cancer women on cytotoxic chemotherapy.

METHODS

One hundred and nine newly diagnosed early and locally advanced postmenopausal breast cancer patients planned for anthracycline and taxane-based chemotherapy were recruited prospectively during the study period from July 2018 to December 2021. BMD of the lumbar spine, the femoral neck, and the total hip were assessed by dual-energy X-ray absorptiometry scan. BMD and FRAX scores were evaluated at baseline, end of chemotherapy, and 6 months of follow-up.

RESULTS

The median age of the study population was 53 (45-65) years. Early and locally advanced breast cancers were seen in 34 (31.2%) and 75 (68.8%) patients, respectively. The duration of follow-up between two BMD measurements was 6 months. The percentage of decrease in BMD at the lumbar spine, femoral neck, and total hip were - 2.36 ± 2.90, - 2.63 ± 3.79, and - 2.08 ± 2.80, respectively (P-value = 0.0001). The median risk of major osteoporotic fracture (MOF) at 10 years (FRAX score) increased from 1.7 (1.4) to 2.7% (2.4) (P-value = 0.0001).

CONCLUSION

This prospective study in postmenopausal breast cancer women shows a significant association of cytotoxic chemotherapy with the worsening of bone health in terms of BMD and FRAX score.

Repeat Bone Mineral Density Screening Measurement and Fracture Prediction in Older Men: A Prospective Cohort Study

CONTEXT

Whether repeated bone mineral density (BMD) screening improves fracture prediction in men is uncertain.

OBJECTIVE

We evaluated whether a second BMD 7 years after the initial BMD improves fracture prediction in older men.

METHODS

Among 3651 community-dwelling men (mean age 79.1 years) with total hip BMD at baseline and Year 7 (Y7), self-reported fractures after Y7 were confirmed by radiographic reports. Fracture prediction assessed using Cox proportional hazards regression and logistic regression with receiver operating characteristic curves for models based on initial BMD, BMD change, and the combination of initial BMD and BMD change (combination model).

RESULTS

During an average follow-up of 8.2 years after Y7, 793 men experienced ≥ 1 clinical fractures, including 426 men with major osteoporotic fractures (MOF) and 193 men with hip fractures. Both initial BMD and BMD change were associated with risk of fracture outcomes independent of each other, but the association was stronger for initial BMD. For example, the multivariable hazard ratio of MOF in the combination model per 1 SD decrement in BMD was 1.76 (95% CI 1.57-1.98) for initial BMD and 1.19 (95% CI 1.08-1.32) for BMD change. Discrimination of fracture outcomes with initial BMD models was somewhat better than with BMD change models and similar to combination models (AUC value for MOF 0.68 [95% CI 0.66-0.71] for initial BMD model, 0.63 [95% CI 0.61-0.66] for BMD change model, and 0.69 [95% CI 0.66-0.71] for combination model).

CONCLUSION

Repeating BMD after 7 years did not meaningfully improve fracture prediction at the population level in community-dwelling older men.

Modeling osteoporosis to design and optimize pharmacological therapies comprising multiple drug types

For the treatment of postmenopausal osteoporosis, several drug classes with different mechanisms of action are available. Since only a limited set of dosing regimens and drug combinations can be tested in clinical trials, it is currently unclear whether common medication strategies achieve optimal bone mineral density gains or are outperformed by alternative dosing schemes and combination therapies that have not been explored so far. Here, we develop a mathematical framework of drug interventions for postmenopausal osteoporosis that unifies fundamental mechanisms of bone remodeling and the mechanisms of action of four drug classes: bisphosphonates, parathyroid hormone analogs, sclerostin inhibitors, and receptor activator of NF-κB ligand inhibitors. Using data from several clinical trials, we calibrate and validate the model, demonstrating its predictive capacity for complex medication scenarios, including sequential and parallel drug combinations. Via simulations, we reveal that there is a large potential to improve gains in bone mineral density by exploiting synergistic interactions between different drug classes, without increasing the total amount of drug administered.

Smoking and fracture risk in men: a meta-analysis of cohort studies, using both frequentist and Bayesian approaches

Past studies indicate that men are more likely to smoke and be at higher risk of smoking-related conditions than women. Our research aimed, through meta-analysis, to assess the association between smoking and fracture risk in men. The following databases were searched, including MEDLINE, EMBASE, Scopus, PsycINFO, ISI Web of Science, Google Scholar, WorldCat, and Open Grey, for identifying related studies. A random-effects model was used to pool the confounder-adjusted relative risk (R.R.). Frequentist and Bayesian hierarchical random-effects models were used for the analysis. The heterogeneity and publication bias were evaluated in this study. Twenty-seven studies met the inclusion criteria. Overall, smoking is associated with a significantly increased risk of fracture in both the frequentist approach (R.R., 1.37; 95% confidence interval: 1.22, 1.53) and the Bayesian approach (R.R., 1.36; 95% credible interval: 1.22, 1.54). Significant heterogeneity was observed in the meta-analysis (Higgin's I² = 83%) and Cochran's Q statistic (p < 0.01). A significant association was also observed in multiple pre-specified sensitivity and subgroup analyses. Similar results were observed in the group containing a large sample size (≥ 10,000 participants), and the group has a small sample size (< 10,000 participants); the pooled R.R was 1.23 (95% confidence interval, 1.07–1.41) and 1.56 (95% confidence interval, 1.37–1.78), respectively. With the Bayesian method, the effect size was 1.23 (95% credible interval, 1.05, 1.45) for the large sample size group and 1.57 (95% credible interval, 1.35, 1.82) for the small sample size group. Smoking is associated with a significant increase in fracture risk for men. Thus, smoking cessation would also greatly reduce fracture risk in all smokers, particularly in men.

DXAGE 2.0 - adult age at death estimation using bone loss in the proximal femur and the second metacarpal

The accurate age at death assessment of unidentified adult skeletal individuals is a critical research task in forensic anthropology, being a key feature for the determination of biological profiles of individual skeletal remains. We have previously shown that the age-related decrease of bone mineral density (BMD) in the proximal femur could be used to assess age at death in women (Navega et al., J Forensic Sci 63:497-503, 2018). The present study aims to generate models for age estimation in both sexes through bone densitometry of the femur and radiogrammetry of the second metacarpal. The training sample comprised 224 adults (120 females, 104 males) from the "Coimbra Identified Skeletal Collection," and different models were generated through least squares regression and general regression neural networks (GRNN). The models were operationalized in a user-friendly online interface at https://osteomics.com/DXAGE2/ . The mean absolute difference between the known and estimated age at death ranges from 9.39 to 13.18 years among women and from 10.33 to 15.76 among men with the least squares regression models. For the GRNN models, the mean absolute difference between documented and projected age ranges from 8.44 to 12.58 years in women and from 10.56 to 16.18 years in men. DXAGE 2.0 enables age estimation in incomplete and/or fragmentary skeletal remains, using alternative skeletal regions, with reliable results.

Follicle-stimulating hormone and blood lead levels with bone mineral density and the risk of fractures in pre- and postmenopausal women

BACKGROUND

The conclusions on the associations of serum follicle-stimulating hormone (FSH) and blood lead levels with bone mineral density (BMD) were controversial. Furthermore, little was known on the impacts of co-existence of serum FSH and blood lead levels on BMD and the risk of fractures in premenopausal and postmenopausal women. Therefore, the present study aimed to examine the associations of serum FSH and blood lead levels with BMD and the risk of fractures in premenopausal and postmenopausal women.

METHODS

Data were derived from the National Health and Nutrition Examination Survey. FSH is assayed using the Microparticle Enzyme Immunoassay technology. Blood lead levels were measured using atomic absorption spectrometry. BMD was measured using dual energy X-ray absorptiometry. Fractures were defined as subjects with fractures in any site of hip, wrist, and spine.

RESULTS

This study included 3798 participants. Elevated blood lead levels were associated with increased serum FSH levels (β= 48.22, 95% CI: 40.21~ 56.22). Serum FSH levels were negatively associated with total femur BMD in pre- and postmenopausal women. However, elevated serum FSH levels were associated with a lower lumbar spine BMD and a higher risk of fractures only in postmenopausal women (β= -0.0010, 95% CI: -0.0015~ -0.0006; OR: 1.007, 95% CI: 1.000~1.014, respectively).

CONCLUSIONS

Serum lead levels were associated with serum FSH levels. Serum FSH levels were associated with a lower BMD and a higher risk of fractures.

Total Hip Bone Mineral Density as an Indicator of Fracture Risk in Bisphosphonate-Treated Patients in a Real-World Setting

Bone mineral density (BMD) is an established measure used to diagnose patients with osteoporosis. In clinical trials, change in BMD has been shown to provide a reliable estimate of fracture risk reduction, and achieved BMD T-score has been shown to reflect the near-term risk of fracture. We aimed to test the association between BMD T-score and fracture risk in patients treated for osteoporosis in a real-world setting. This retrospective, observational cohort study included Swedish females aged ≥55 years who had a total hip BMD measurement at one of three participating clinics. Patients were separated into two cohorts: bisphosphonate-treated and bisphosphonate-naïve prior to BMD measurement, stratified by age and prior nonvertebral fracture status. The primary outcome was cumulative incidence of clinical fractures within 24 months of BMD measurement, with other fracture types included as secondary outcomes. Associations between T-score and fracture risk were estimated using proportional hazards regression and restricted cubic splines. A total of 15,395 patients were analyzed: 11,973 bisphosphonate-naïve and 3422 bisphosphonate-treated. In the 24 months following BMD measurement, 6.3% (95% confidence interval [CI], 5.9-6.7) of bisphosphonate-naïve and 8.4% (95% CI, 7.5-9.4) of bisphosphonate-treated patients experienced a clinical fracture. Strong inverse relationships between BMD T-score and fracture incidence were observed in both cohorts. Among bisphosphonate-naïve patients, this relationship appeared to plateau around T-score -1.5, indicating smaller marginal reductions in fracture risk above this value; bisphosphonate-treated patients showed a more consistent marginal change in fracture risk across the evaluated T-scores (-3.0 to -0.5). Trends remained robust regardless of age and prior fracture status. This real-world demonstration of a BMD-fracture risk association in both bisphosphonate-naïve and bisphosphonate-treated patients extends evidence from clinical trials and recent meta-regressions supporting the suitability of total hip BMD as a meaningful outcome for the clinical management of patients with osteoporosis. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

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.

Effects of thyroid-stimulating hormone suppression after thyroidectomy for thyroid cancer on bone mineral density in postmenopausal women: a systematic review and meta-analysis

OBJECTIVES

We assessed thyroid-stimulating hormone (TSH) suppression effects on bone mineral density (BMD) in postmenopausal women who underwent thyroidectomy.

DATA SOURCES

PubMed, EMBASE, Cochrane Library, Web of Science and SCOPUS were searched from inception to 24 February 2021.

STUDY SELECTION

Case-control studies were included.

DATA EXTRACTION AND SYNTHESIS

Two authors independently reviewed the studies, extracted the data and performed meta-analysis of eligible studies.

RESEARCH DESIGN AND METHODS

Studies evaluating BMD in postmenopausal women with thyroid cancer who had thyroidectomy and levothyroxine therapy were included. Differences in BMD were presented as standardised mean differences (SMDs). Meta-analyses were conducted using a random-effects model.

RESULTS

Analysis of 16 case-control studies (426 patients and 701 controls without thyroid cancer) showed that stringent TSH suppression (TSH <0.10 mIU/L) after thyroidectomy had deleterious effects on the BMD of the lumbar spine in postmenopausal women compared with controls (SMD -0.55; 95% CI -0.99 to -0.10; I²=75.8%). There was no significant difference in patients with moderate TSH suppression (TSH 0.10-0.49 mIU/L). TSH suppression in postmenopausal women was not significantly associated with lower femoral neck BMD. Subgroup analysis of the lumbar spine showed that the association between stringent TSH suppression and lower BMD was consistent among studies with >10 years of follow-up (SMD -0.32; 95% CI -0.50 to -0.14). Subgroup analysis of the femoral neck showed that total thyroidectomy was related to detrimental effects on the BMD of the femoral neck (SMD -0.60; 95% CI -0.89 to -0.31; I²=90.4%), but near-total thyroidectomy was not (SMD 0.00; 95% CI -0.30 to 0.30; I²=55.6%).

CONCLUSIONS

Stringent TSH suppression had deleterious effects on the BMD of the lumbar spine after thyroidectomy in postmenopausal women. Further studies are needed to determine whether stringent TSH suppression after thyroidectomy increases the fracture risk.

Effect of cytotoxic chemotherapy on bone health among breast cancer patients. Does it require intervention?

BACKGROUND

Breast cancer (BC) is one of the most common malignancies worldwide. Although the burden and mechanisms of endocrine therapy-related bone loss are known, the evidence is scanty regarding the impact of cytotoxic chemotherapy on bone health. We have attempted to summarize the effect of cytotoxic chemotherapy on bone health in BC patients.

METHODS

A comprehensive literature search was performed via MEDLINE and Cochrane library databases to evaluate the effect of chemotherapy on bone health among women with BC. We included articles related to skeletal-related events, bone mineral density, bone turnover markers, osteoporosis-specific quality of life, bisphosphonate, and other bone-directed therapy. We excluded articles that included patients with metastatic breast cancer and patients receiving hormonal therapy.

DISCUSSION

Bone microenvironment in cancer is directly or indirectly influenced by clinical, hormonal, nutritional, and treatment factors. Calcitonin, parathyroid hormone, calcitriol, and estrogen are the major hormonal regulators. Bone turnover markers, namely bone formation and resorption markers, have been used to predict bone loss, fracture risk, and monitoring treatment response. Chemotherapeutic drugs such as anthracyclines and taxanes synergistically affect BMD and quality of life. Calcium, vitamin D, bisphosphonates, and denosumab are supplemented to prevent excess bone resorption. Bone-targeted anti-resorptive agents have been studied as potential anticancer agents in the adjuvant treatment of breast cancer.

CONCLUSION

This review summarizes the negative effect of chemotherapy on bone health of BC patients and the importance of preventing or treating bone loss.

The association of osteochemometrics and bone mineral density in humans

OBJECTIVES

Even though much is known about bone mineral and matrix composition, studies about their relationship with several bone properties and its alterations related to bone diseases such as osteoporosis are practically non-existent in humans. Thus, the development of methods to understand the effects of bone properties at a microscopic level is paramount. This research aimed to evaluate whether Fourier transform infrared-attenuated total reflectance (FTIR-ATR) band intensity ratios correlate with femoral bone mass, bone mineral content (BMC) (total and femoral neck), bone mineral per unit area (BMD) (total, femoral neck, greater trochanter, intertrochanteric region, and Ward's area) and the area (total and femoral neck). A sample of femora from the 21st Century Identified Skeleton Collection (N = 78, 42 females and 36 males) was employed and BMC, BMD, and the femoral areas were acquired by DXA.

RESULTS

It was found that only females' BMD had a significant association with the femoral FTIR-ATR indices under study, whereas bone collagen (Am/P) and the content of carbonate Type A (API) in males correlated with the total proximal femur area of the regions of interest and the femoral neck area.

DISCUSSION

Men and women showed different changes related to their chemical composition in BMD, BMC, and probed area, most likely due to differences in structure and physiology, as well as mechanical strength in the proximal femoral sites where BMD was analyzed.

Peak trabecular bone microstructure predicts rate of estrogen-deficiency-induced bone loss in rats

Postmenopausal osteoporosis affects a large number of women worldwide. Reduced estrogen levels during menopause lead to accelerated bone remodeling, resulting in low bone mass and increased fracture risk. Both peak bone mass and the rate of bone loss are important predictors of postmenopausal osteoporosis risk. However, whether peak bone mass and/or bone microstructure directly influence the rate of bone loss following menopause remains unclear. Our study aimed to establish the relationship between peak bone mass/microstructure and the rate of bone loss in response to estrogen deficiency following ovariectomy (OVX) surgery in rats of homogeneous background by tracking the skeletal changes using in vivo micro-computed tomography (μCT) and three-dimensional (3D) image registrations. Linear regression analyses demonstrated that the peak bone microstructure, but not peak bone mass, was highly predictive of the rate of OVX-induced bone loss. In particular, the baseline trabecular thickness was found to have the highest correlation with the degree of OVX-induced bone loss and trabecular stiffness reduction. Given the same bone mass, the rats with thicker baseline trabeculae had a lower rate of trabecular microstructure and stiffness deterioration after OVX. Moreover, further evaluation to track the changes within each individual trabecula via our novel individual trabecular dynamics (ITD) analysis suggested that a trabecular network with thicker trabeculae is less likely to disconnect or perforate in response to estrogen deficiency, resulting a lower degree of bone loss. Taken together, these findings indicate that the rate of estrogen-deficiency-induced bone loss could be predicted by peak bone microstructure, most notably the trabecular thickness. Given the same bone mass, a trabecular bone phenotype with thin trabeculae may be a risk factor toward accelerated postmenopausal bone loss.

Clinical Criteria Can Identify Children With Osteopenia in Newly Diagnosed Crohn Disease

OBJECTIVES

Chronic inflammation of Crohn disease (CD) is associated with reduced bone mineral density (BMD). As bone mass is almost exclusively accrued during childhood, early recognition of osteopenia is especially important in pediatric CD. We aimed to identify variables associated with osteopenia to guide dual-energy X-ray absorptiometry (DXA) scan screening to those who most need it.

METHODS

This was a retrospective inception cohort study of children newly diagnosed with CD, and routinely referred to DXA scans. Demographic and explicit clinical data were recorded along with whole-body less head BMD, adjusted for age, sex, and height by z-scores.

RESULTS

Of the 116 included children (mean age 13 ± 3.1 years, 67 [58%] boys, mean body mass index [BMI] 16.7 ± 2.6), 63 (54%) had normal BMD (z-score > -1) or borderline osteopenia (-1 ≥ z-score > -2) and 53 (46%) had osteopenia (z-score ≤ -2). Osteopenia was associated with lower BMI z-score (-0.8 ± 1.2 vs -1.8 ± 1.1, P < 0.001) and higher PCDAI (33.7 ± 15.2 vs 25.7 ± 16.5; P = 0.009) than those with BMD z-score >-2. In total, 59% of children with BMI z-score <-0.5 had moderate-severe osteopenia and only 18% of those with higher z-scores. Multivariate logistic regression identified BMI z-score as the sole risk factor (OR 1.28 [95% CI 1.08-1.52], P = 0.005). BMI z-score ≥-0.5 excludes osteopenia with a sensitivity 87%, specificity 49%, NPV 82%, and PPV 59%.

CONCLUSIONS

Osteopenia was found in nearly half of children with newly onset CD. BMI z-score <-0.5 should prompt referral to DXA screening.

Association between a literature-based genetic risk score and bone mineral density of African American women in Women Health Initiative Study

Genetic risk of low BMD in African American women remains unclear. Based on SNPs discovered from a predominantly Caucasian sample, genetic profile was summarized and was found to be significantly associated with BMD variation in African American women.

INTRODUCTION

Osteoporosis is largely under-recognized and undertreated in African-American women, the post-fracture morbidity and mortality rates in this racial group is rather high. Since BMD was proved to be highly heritable, based on a comprehensive genome-wide meta-analysis that reported 63 BMD-related single nucleotide polymorphisms (SNPs), we aim to unravel the overall genetic risk for decreased BMD and osteoporosis in African-American women.

METHODS

Genotype data of 842 African American women in a Women's Health Initiative cohort were analyzed. Comprehensive genotype imputation was conducted at the Sanger Imputation Server. Multi-locus genetic risk scores (GRSs) based on 62 BMD-related single-nucleotide polymorphisms (SNPs) were calculated. The association between GRS and BMD was assessed by regression analysis. Longitudinal data was further analyzed using a generalized estimating equation, which helps achieve more efficient and unbiased regression parameters by accounting for the within-subject correlation of responses on dependent variables.

RESULTS

After adjusting for age, body weight, hormone use, and previous fracture, for every unit increase of GRS.FN and GRS.LS, BMD at hip and lumbar spine decreased 0.124 g/cm² and 0.086 g/cm², respectively. Collectively, the model accounted for 34.95% of the femoral neck BMD variation and 25.79% of lumbar spine BMD variation. Notably, GRS.FN and GRS.LS accounted for 2.03% and 2.39% of the total explained variance, respectively. The proportion of BMD variation can be explained by GRSs increasing as participants aged.

CONCLUSIONS

Genetic risk score was significantly associated with lower BMD in the current study, suggesting that SNPs discovered from prior meta-analysis based on primarily Caucasian population can also explain a considerable proportion of BMD variation in African Americans.

The Role of Egg Production in the Etiology of Keel Bone Damage in Laying Hens

Keel bone fractures and deviations belong to the most severe animal welfare problems in laying hens and are influenced by several factors such as husbandry system and genetic background. It is likely that egg production also influences keel bone health due to the high demand of calcium for the eggshell, which is, in part, taken from the skeleton. The high estrogen plasma concentration, which is linked to the high laying performance, may also affect the keel bone as sexual steroids have been shown to influence bone health. The aim of this study was to investigate the relationship between egg production, genetically determined high laying performance, estradiol-17ß concentration, and keel bone characteristics. Two hundred hens of two layer lines differing in laying performance (WLA: high performing; G11: low performing) were divided into four treatment groups: Group S received an implant containing a GnRH agonist that suppressed egg production, group E received an implant containing the sexual steroid estradiol-17ß, group SE received both implants, and group C were kept as control hens. Between the 12th and the 62nd weeks of age, the keel bone of all hens was radiographed and estradiol-17ß plasma concentration was assessed at regular intervals. Non-egg laying hens showed a lower risk of keel bone fracture and a higher radiographic density compared to egg laying hens. Exogenous estradiol-17ß was associated with a moderately higher risk of fracture within egg laying but with a lower risk of fracture and a higher radiographic density within non-egg laying hens. The high performing layer line WLA showed a significantly higher fracture risk but also a higher radiographic density compared to the low performing layer line G11. In contrast, neither the risk nor the severity of deviations were unambiguously influenced by egg production or layer line. We assume that within a layer line, there is a strong association between egg production and keel bone fractures, and, possibly, bone mineral density, but not between egg production and deviations. Moreover, our results confirm that genetic background influences fracture prevalence and indicate that the selection for high laying performance may negatively influence keel bone health.

Patient Age Is Inversely Associated with Injury Counts Caused by Motor Vehicle Crashes

Associations between age and fracture incidence, total number of fractures, and total number of injuries per occupant occurring in motor vehicle crashes were evaluated. An observational study of the Crash Injury Research and Engineering Network was conducted. Multivariable logistic regression and negative binomial models were used to relate age (2064, 65+ years) to fracture incidence, total number of fractures per occupant, and total number of injuries, adjusting for sex and change in vehicle velocity (deltav). Over 90% of occupants had at least one fracture for a total of 5,846 fracture injuries. The older age group experienced a 15% increase in the incidence of total injuries sustained compared to the younger group (Incident Rate Ratio = 1.15, 95% Confidence Interval = 1.081.23, p 0.0001). Older patients should be considered for polytrauma evaluation even with a lower energy motor vehicle crash. (Journal of Surgical Orthopaedic Advances 29(1):3639, 2020).

Estradiol and Follicle-Stimulating Hormone as Predictors of Onset of Menopause Transition-Related Bone Loss in Pre- and Perimenopausal Women

The menopause transition (MT) may be an opportunity for early intervention to prevent rapid bone loss. To intervene early, we need to be able to prospectively identify pre- and perimenopausal women who are beginning to lose bone. This study examined whether estradiol (E2), or follicle-stimulating hormone (FSH), measured in pre- and perimenopausal women, can predict significant bone loss by the next year. Bone loss was considered significant if bone mineral density (BMD) decline at the lumbar spine (LS) or femoral neck (FN) from a pre- or early perimenopausal baseline to 1 year after the E2 or FSH measurement was greater than the least detectable change. We used data from 1559 participants in the Study of Women's Health Across the Nation and tested E2 and FSH as separate predictors using repeated measures modified Poisson regression. Adjusted for MT stage, age, race/ethnicity, and body mass index, women with lower E2 (and higher FSH) were more likely to lose BMD: At the LS, each halving of E2 and each doubling of FSH were associated with 10% and 39% greater risk of significant bone loss, respectively (p < 0.0001 for each). At the FN, each halving of E2 and each doubling of FSH were associated with 12% (p = 0.01) and 27% (p < 0.001) greater risk of significant bone loss. FSH was more informative than E2 (assessed by the area under the receiver-operator curve) at identifying women who were more versus less likely to begin losing bone, especially at the LS. Prediction was better when hormones were measured in pre- or early perimenopause than in late perimenopause. Tracking within-individual change in either hormone did not predict onset of bone loss better than a single measure. We conclude that measuring FSH in the MT can help prospectively identify women with imminent or ongoing bone loss at the LS. © 2019 American Society for Bone and Mineral Research.

Repeating Measurement of Bone Mineral Density when Monitoring with Dual-energy X-ray Absorptiometry: 2019 ISCD Official Position

Bone mineral density (BMD) can be measured at multiple skeletal sites using various technologies to aid clinical decision-making in bone and mineral disorders. BMD by dual-energy X-ray absorptiometry (DXA) has a critical role in predicting risk of fracture, diagnosis of osteoporosis, and monitoring patients. In clinical practice, DXA remains the most available and best validated tool for monitoring patients. A quality baseline DXA scan is essential for comparison with all subsequent scans. Monitoring patients with serial measurements requires technical expertise and knowledge of the least significant change in order to determine when follow-up scans should be repeated. Prior ISCD Official Positions have clarified how and when repeat DXA is useful as well as the interpretation of results. The 2019 ISCD Official Positions considered new evidence and clarifies if and when BMD should be repeated. There is good evidence showing that repeat BMD measurement can identify people who experience bone loss, which is an independent predictor of fracture risk. There is good evidence showing that the reduction in spine and hip fractures with osteoporosis medication is proportional to the change in BMD with treatment. There is evidence that measuring BMD is useful following discontinuation of osteoporosis treatment. There is less documentation addressing the effectiveness of monitoring BMD to improve medication adherence, whether monitoring of BMD reduces the risk of fracture, or effectively discriminates patients who should and should not recommence treatment following an interruption of medication. Further research is needed in all of these areas.

Significant association between skeletal bone mineral density and moderate to severe periodontitis in fair oral hygiene individuals

AIM

This cross-sectional study aimed to investigate the association between skeletal bone mineral density (BMD) and periodontitis in Thai adults and elders.

METHODS

This study comprised 3282 participants aged 30-82 years. BMD was assessed at 3 skeletal sites using dual-energy X-ray absorptiometry. Each participant's BMD status was classified as normal, osteopenia or osteoporosis. Periodontal assessments were the number of remaining teeth, plaque score, probing depth and clinical attachment level (CAL). The participants were classified into no/mild or moderate/severe periodontitis groups. The mean periodontal variables between BMD categories were compared. The association between the BMD status and moderate/severe periodontitis was analyzed using binary logistic regression.

RESULTS

Among the BMD categories, the greatest mean CAL and the lowest mean number of remaining teeth were found in the osteoporosis group. The mean CAL difference between the osteoporosis and normal BMD groups was 0.3 mm. In 337 participants with a plaque score of less than 40%, there was a significant association between osteoporosis and moderate/severe periodontitis.

CONCLUSION

Skeletal BMD in the osteoporosis range was associated with moderate/severe periodontitis in individuals with fair oral hygiene, suggesting the benefit of special attention to the skeletal bone health of these individuals.

Predictors of imminent non-vertebral fracture in elderly women with osteoporosis, low bone mass, or a history of fracture, based on data from the population-based Canadian Multicentre Osteoporosis Study (CaMos)

Using data from the Canadian Multicentre Osteoporosis Study, several risk factors predictive of imminent (2-year) risk of low-trauma non-vertebral fracture among high-risk women were identified, including history of falls, history of low-trauma fracture, poorer physical function, and lower T score. Careful consideration should be given to targeting this population for therapy.

PURPOSE

Fracture risk assessment has focused on a long-term horizon and populations with a broad risk range. For elderly women with osteoporosis or low bone mass, or a history of fragility fractures ("high-risk women"), risk prediction over a shorter horizon may have greater clinical relevance.

METHODS

A repeated-observations design and data from the Canadian Multicentre Osteoporosis Study were employed. Study population comprised women aged ≥ 65 years with T score (total hip, femoral neck, spine) ≤ - 1.0 or prior fracture. Hazard ratios (HR) for predictors of low-trauma non-vertebral fracture during 2-year follow-up were estimated using multivariable shared frailty model.

RESULTS

The study population included 3228 women who contributed 5004 observations; 4.8% experienced low-trauma non-vertebral fracture during the 2-year follow-up. In bivariate analyses, important risk factors included age, back pain, history of falls, history of low-trauma fracture, physical function, health status, and total hip T score. In multivariable analyses, only four independent predictors were identified: falls in past 12 months (≥ 2 falls: HR = 1.9; 1 fall: HR = 1.5), low-trauma fracture in past 12 months (≥ 1 fracture: HR = 1.7), SF-36 physical component summary score (≤ 42.0: HR = 1.6), and total hip T score (≤ - 3.5: HR = 3.7; > - 3.5 to ≤ - 2.5: HR = 2.5; > - 2.5 to ≤ - 1: HR = 1.3).

CONCLUSIONS

Imminent risk of low-trauma non-vertebral fracture is elevated among high-risk women with a history of falls or low-trauma fracture, poorer physical function, and lower T score. Careful consideration should be given to identifying and targeting this population for therapy.

Lithium use and risk of fracture: a systematic review and meta-analysis of observational studies

This systematic review and meta-analysis summarized the results from nine eligible observational studies. Lithium use was significantly associated with a decrease risk of fractures.

INTRODUCTION

The association between lithium use and risk of fracture is uncertain. To date, there have been no meta-analyses that have studied the association between the two. We conducted a systematic review and meta-analysis to examine the effect of lithium medication on the risk of fracture.

METHODS

A comprehensive literature search was performed in PubMed, Embase, and MEDLINE to include eligible observational studies. Three reviewers conducted the literature search, study selection, study appraisal, and data abstraction independently. Random effects models were used to obtain the overall estimate for meta-analysis. Cochran's Q and Higgins' I² were used to assess heterogeneity. A funnel plot and Egger's regression test were employed to assess publication bias.

RESULTS

Of the 3819 studies that were identified by our search strategy, eight were eligible for the systematic review, while seven of them qualified for the meta-analysis. In studies that reported risk ratio (RR) of fracture as an outcome (five studies [n = 1,134,722]), lithium use was associated with a 20% decrease in risk of fracture (RR = 0.80; 95% CI, 0.73-0.87; p < 0.01). A decreased risk of fracture associated with lithium was also observed in studies that adjusted for previous fractures (RR = 0.81; 95% CI, 0.73-0.89; p < 0.01). The decreased risk of fracture associated with lithium use remained consistent in all the analyses with different inclusion criteria. Neither significant heterogeneity nor significant publication bias was observed.

CONCLUSION

The present systematic review and meta-analysis demonstrated that lithium use was associated with a significant decreased risk of fracture.

Accelerated Bone Loss in Older Men: Effects on Bone Microarchitecture and Strength

Accelerated bone loss (ABL) shown on routine dual-energy X-ray absorptiometry (DXA) may be accompanied by microarchitectural changes, increased cortical porosity, and lower bone strength. To test this hypothesis, we performed a cross-sectional study and used high-resolution peripheral quantitative computed tomography (HR-pQCT) scans (Scanco Medical AG, Brüttisellen, Switzerland) to measure estimated bone strength and microarchitecture in the distal radius and distal and diaphyseal tibia. We studied 1628 men who attended the year 14 exam of the Osteoporotic Fractures in Men (MrOS) study. We retrospectively characterized areal bone mineral density (aBMD) change from the year 7 to year 14 exam in three categories: "accelerated" loss, ≥10% loss at either the total hip or femoral neck (n = 299, 18.4%); "expected" loss, <10% (n = 1061, 65.2%), and "maintained" BMD, ≥0% (n = 268, 16.5%). The ABL cut-off was a safety alert established for MrOS. We used regression models to calculate adjusted mean HR-pQCT parameters in men with ABL, expected loss, or maintained BMD. Men who experienced ABL were older and had a lower body mass index and aBMD and experienced greater weight loss compared with other men. Total volumetric BMD and trabecular and cortical volumetric BMD were lower in men with ABL compared with the expected or maintained group. Men with ABL had significantly lower trabecular bone volume fraction (BV/TV), fewer trabeculae, and greater trabecular separation at both the distal radius and tibia than men with expected loss or who maintained aBMD, all p trend <0.001. Men with ABL had lower cortical thickness and lower estimated bone strength, but there was no difference in cortical porosity except at the tibia diaphyseal site. In summary, men with ABL have lower estimated bone strength, poorer trabecular microarchitecture, and thinner cortices than men without ABL but have similar cortical porosity. These impairments may lead to an increased risk of fracture. © 2018 American Society for Bone and Mineral Research.

The effect of glucocorticoids on bone mineral density in patients with rheumatoid arthritis: A systematic review and meta-analysis of randomized, controlled trials

PURPOSE

The role of glucocorticoids in the treatment of rheumatoid arthritis (RA) is widely debated. Impairment of bone formation may be counter-balanced by reduced systemic inflammation. This review aims to assess the effect of prednisolone/prednisone on bone mineral density (BMD) in patients with RA analyzed in randomized, controlled trials.

METHODS

We performed a systematic literature search and identified randomized, double-blinded placebo-controlled studies including patients with RA and using prednisolone or prednisone as the intervention. We selected studies that measured BMD by DXA at baseline and at least once thereafter. Two authors independently performed reference review, data extraction and risk of bias assessment. Primary outcome was mean change in BMD from baseline to follow-up. Secondary endpoints included radiographic scores, RA disease activity indices and fractures. We rated the quality of evidence using the GRADE approach. Outcomes were standardized for meta-analyses and 95% confidence intervals (95% CI) were calculated.

RESULTS

We identified 7 studies and included previously unpublished data. Studies were similar regarding study population and intervention. Standard mean difference (SMD) in change in BMD from 0 to 24 months was -0.02 (95%CI -0.16, 0.12) at the lumbar spine and -0.11 (95% CI -0.25, 0.02) at the hip (both high quality evidence) between patients treated with prednisolone/prednisone or not. Data completeness was low in some studies, concomitant treatment of RA differed between studies and differences in use of anti-osteoporotic medication may have influenced the results. However, sensitivity analyses excluding studies in which participants used either the most or the least potent concomitant RA treatment or used anti-osteoporotic therapies did not alter the estimates.

CONCLUSIONS

In patients with early and active RA, we found no difference in change in BMD between patients treated with prednisone/prednisolone versus placebo, suggesting that at least through 24 months, the suppression of inflammation by glucocorticoids may counterbalance their adverse effects on bone remodeling.

Progesterone for the prevention and treatment of osteoporosis in women

Estradiol (E2) is women's dominant 'bone hormone' since it is essential for development of adolescent peak bone mineral density (BMD) and physiological levels prevent the rapid (3-week) bone resorption that causes most adult BMD loss. However, deceasing E2 levels trigger bone resorption/loss. Progesterone (P4) is E2's physiological partner, collaborating with E2 in every cell/tissue; its bone 'job' is to increase P4-receptor-mediated, slow (3-4 months) osteoblastic new bone formation. When menstrual cycles are normal length and normally ovulatory, E2 and P4 are balanced and BMD is stable. However, clinically normal cycles commonly have ovulatory disturbances (anovulation, short luteal phases) and low P4 levels; these are more frequent in teen and perimenopausal women and increased by everyday stressors: energy insufficiency, emotional/social/economic threats and illness. Meta-analysis shows that almost 1%/year spinal BMD loss occurs in those with greater than median (∼31%) of ovulatory disturbed cycles. Prevention of osteoporosis and fragility fractures requires the reversal of stressors, detection and treatment of teen-to-perimenopausal recurrent cycle/ovulatory disturbances with cyclic oral micronized progesterone. Low 'Peak Perimenopausal BMD' is likely the primary risk for fragility fractures in later life. Progesterone plus estradiol or other antiresorptive therapies adds 0.68%/year and may be a highly effective osteoporosis treatment. Randomized controlled trials are still needed to confirm progesterone's important role in women's bone formation.

Lower Bone Density, Impaired Microarchitecture, and Strength Predict Future Fragility Fracture in Postmenopausal Women: 5-Year Follow-up of the Calgary CaMos Cohort

The aim of this prospective study was to use high-resolution peripheral quantitative computed tomography (HR-pQCT) to determine if baseline skeletal parameters can predict incident fragility fracture in women and, secondly, to establish if women that fracture lose bone at a faster rate than those who do not fracture. Women older than 60 years who experienced a fragility fracture during the 5-year follow-up period (incident fracture group, n = 22) were compared with those who did not experience a fragility fracture during the study (n = 127). After image registration between baseline and follow-up measures, standard and cortical morphological analyses were conducted. Odds ratios were calculated for baseline values and annualized percent change of HR-pQCT and finite element variables. At the radius, baseline HR-pQCT results show women who fractured had lower total bone mineral density (Tt.BMD; 19%), trabecular bone mineral density (Tb.BMD; 25%), and trabecular number (Tb.N; 14%), with higher trabecular separation (Tb.Sp; 19%) than women who did not fracture. At the tibia, women with incident fracture had lower Tt.BMD (15%), Tb.BMD (12%), cortical thickness (Ct.Th; 14%), cortical area (Ct.Ar; 12%), and failure load (10%) with higher total area (Tt.Ar; 7%) and trabecular area (Tb.Ar; 10%) than women who did not fracture. Odds ratios (ORs) at the radius revealed every SD decrease of Tt.BMD (OR = 2.1), Tb.BMD (OR = 2.0), and Tb.N (OR = 1.7) was associated with a significantly increased likelihood of fragility fracture. At the tibia, every SD decrease in Tt.BMD (OR = 2.1), Tb.BMD (OR = 1.7), Ct.Th (OR = 2.2), Ct.Ar (OR = 1.9), and failure load (OR = 1.7) were associated with a significantly increased likelihood of fragility fracture. Irrespective of scanning modality, the annualized percent rate of bone loss was not different between fracture groups. The results suggest baseline bone density, microarchitecture, and strength rather than change in these variables are associated with incident fragility fractures in women older than 60 years. Furthermore, irrespective of fragility fracture status, women experienced changes in skeletal health at a similar rate. © 2017 American Society for Bone and Mineral Research.

Adipose tissue depot volume relationships with spinal trabecular bone mineral density in African Americans with diabetes

Changes in select adipose tissue volumes may differentially impact bone mineral density. This study was performed to assess cross-sectional and longitudinal relationships between computed tomography-determined visceral (VAT), subcutaneous (SAT), inter-muscular (IMAT), and pericardial adipose tissue (PAT) volumes with respective changes in thoracic vertebral and lumbar vertebral volumetric trabecular bone mineral density (vBMD) in African Americans with type 2 diabetes. Generalized linear models were fitted to test relationships between baseline and change in adipose volumes with change in vBMD in 300 African American-Diabetes Heart Study participants; adjustment was performed for age, sex, diabetes duration, study interval, smoking, hypertension, BMI, kidney function, and medications. Participants were 50% female with mean ± SD age 55.1±9.0 years, diabetes duration 10.2±7.2 years, and BMI 34.7±7.7 kg/m². Over 5.3 ± 1.4 years, mean vBMD decreased in thoracic/lumbar spine, while mean adipose tissue volumes increased in SAT, IMAT, and PAT, but not VAT depots. In fully-adjusted models, changes in lumbar and thoracic vBMD were positively associated with change in SAT (β[SE] 0.045[0.011], p<0.0001; 0.40[0.013], p = 0.002, respectively). Change in thoracic vBMD was positively associated with change in IMAT (p = 0.029) and VAT (p = 0.016); and change in lumbar vBMD positively associated with baseline IMAT (p<0.0001). In contrast, vBMD was not associated with change in PAT. After adjusting for BMI, baseline and change in volumes of select adipose depots were associated with increases in thoracic and lumbar trabecular vBMD in African Americans. Effects of adiposity on trabecular bone appear to be site-specific and related to factors beyond mechanical load.

Utility of DXA for monitoring, technical aspects of DXA BMD measurement and precision testing

Monitoring a patient's bone mineral density (BMD) is one of the main reasons for dual-energy X-ray absorptiometry (DXA) referral. It is widely recommended by clinical guidelines, and the accepted standard in practice for managing patients with osteoporosis and other disorders. Clinicians and DXA providers must be familiar with the scientific rationale and procedures involved in measurement science to obtain accurate and reproducible results. Their importance is critical to maximise the value of scan acquisition and interpretation. Scanning individual patients, with different needs and disorders, requires excellence in training, experience, and is more complex than just simply 'measuring BMD'. Over the past 3 decades many studies have validated the importance of monitoring BMD for fracture risk assessment, and for patients on osteoporosis treatment. New DXA features enhance the value of DXA monitoring today. Quality BMD measurement remains an essential component of patient care in osteoporosis and other disorders, playing a critical role in informed decision making for clinicians assessing and managing their patients. In this article we describe some of the technical aspects of measurement and discuss the utility of DXA for monitoring patients in clinical practice.

Older Men With Anemia Have Increased Fracture Risk Independent of Bone Mineral Density

CONTEXT

Extremely low hemoglobin (Hgb) values have been linked to increased fracture risk at different sites. However, careful assessment of clinically defined anemia and fracture risk is lacking.

OBJECTIVE

To determine whether men with anemia were at increased risk of fracture after accounting for bone mineral density (BMD) and bone loss.

DESIGN

Cross-sectional analysis (at visit 3) and prospective analysis (from baseline to visit 3) in the Osteoporotic Fractures in Men (MrOS), a multisite, longitudinal cohort study.

SETTING

Six communities in the United States.

PARTICIPANTS

A total of 3632 community-dwelling men (age ≥65 years) in MrOS at baseline (2000 through 2002) who were able to walk unassisted, did not have hip replacement or fracture, and had complete blood cell counts at visit 3 (2007 through 2009).

OUTCOMES

Adjudicated spine and nonspine fractures during a median 7.2 years of follow-up.

RESULTS

Analytic baseline characteristics associated with fractures or anemia (defined as Hgb <12 g/dL) were included in multivariable models. Anemia was associated with increased risk of any fracture [hazard ratio (HR), 1.67; 95% confidence interval (CI), 1.26 to 2.21] and nonspine fracture (HR, 1.70; 95% CI, 1.25 to 2.31). A model including change in BMD slightly attenuated the association with any (HR, 1.60; 95% CI, 1.20 to 2.13) and nonspine fractures (HR, 1.57; 95% CI, 1.14 to 2.15). Including absolute BMD did not significantly alter the anemia-fracture association. Anemia was not associated with spine fracture.

CONCLUSIONS

Community-dwelling older men with anemia had a 57% to 72% increase in nonspine fracture risk independent of BMD and bone loss.

The prevalence of osteoporosis and the rate of bone loss in Korean adults: the Chungju metabolic disease cohort (CMC) study

Because the rate of bone loss is an important risk factor for fracture, we studied longitudinal changes in bone mineral density (BMD). Although the BMD of the hip decreased over time, spine BMD remained largely stable or increased. Therefore, spine BMD may not be appropriate for assessing BMD change.

INTRODUCTION

The rate of age-dependent bone loss has been shown to be an important risk factor for fracture. However, longitudinal rates of BMD loss in Korea have not yet been reported. The objective of this study was to evaluate longitudinal changes in BMD in Korea.

METHODS

This cohort study was performed in a population of individuals 40 years of age or older living in the rural area of Chungju City, Korea. A second BMD examination was conducted approximately 4 years after a baseline examination. A total of 3755 of the 6007 subjects completed the follow-up visit, corresponding to a follow-up rate of 62.51%.

RESULTS

The age-standardized osteoporosis prevalence was 12.81% in males and 44.35% in females. In males, the average annual BMD loss at the total hip increased from -0.25% per year in their 40s to -1.12% per year in their 80s. In females, the average annual BMD loss at the total hip increased from -0.69% per year in their 40s to -1.51% per year in their 80s. However, the average annual percentage change in spine BMD in females increased from -0.91% per year in their 40s to +1.39% per year in their 80s.

CONCLUSIONS

A substantial number of subjects had osteoporosis, even though we standardized the prevalence of osteoporosis. In total hip, the mean BMD was decreased during the follow-up period; in addition, the annual percentage loss increased with age. However, spine BMD remained approximately stable or increased over time and therefore may not be appropriate for assessing BMD change.

Premenopausal Trabecular Bone Loss is Associated with a Family History of Fragility Fracture

INTRODUCTION

Although a fragility fracture family history (FFFH+) has repeatedly been shown to be associated with lower bone mineral density (BMD), its relationship to human BMD change is unclear. Animal research, however, documented that different purebred strains within rodent species have wide ranges in rates of bone acquisition during growth as well as in change post-ovariectomy. Our objective was to compare the rate of premenopausal spinal trabecular BMD change between women with and without a general family history of fragility fracture.

PARTICIPANTS AND METHODS

Healthy premenopausal community women participated in prospective observational studies at two academic medical research centres: Vancouver, Canada (n = 66) and Munich, Germany (n = 20). The primary outcome was annual spinal BMD change, measured by quantitative computed tomography (QCT). The two studies employed similar methodologies for assessing QCT and FFFH.

RESULTS

Volunteer community participants had a mean age of 36.0 (SD, 6.9) years, body mass index 22.5 (2.4) and baseline QCT of 150.2 (22.5) mg/cm³ trabecular bone. The rates of BMD change were similar in both cities: - 3.5 (5.1)/year Vancouver, - 2.0 (3.4)/year Munich (95 % CI of difference: - 3.9, 0.9). Over a third of the women (31 of the 86, 36 %) reported FFFH+. Those with and without a FFFH were similar in demographics, nutrition, exercise, menstrual cycle and luteal phase lengths and physiological measures (serum calcium, osteocalcin and estradiol). However, women with FFFH+ lost trabecular BMD more rapidly: FFFH+, - 4.9 (5.0), FFFH-, - 2.2 (4.4) mg/cm³/year (95 % CI diff - 0.7 to - 4.8, F_1.83 = 7.88, p = 0.006). FFFH+ explained 7.7 % of the variance in QCT volumetric trabecular spinal bone change/year in these healthy premenopausal women.

CONCLUSION

This study shows for the first time that having a history of a fragility fracture in a family member is associated with a greater rate of premenopausal spinal trabecular bone loss.

Changes in Bone Mineral Density in the Year after Critical Illness

RATIONALE

Critical illness may be associated with increased bone turnover and loss of bone mineral density (BMD). Prospective evidence describing long-term changes in BMD after critical illness is needed to further define this relationship.

OBJECTIVES

To measure the change in BMD and bone turnover markers (BTMs) in subjects 1 year after critical illness compared with population-based control subjects.

METHODS

We studied adult patients admitted to a tertiary intensive care unit (ICU) who required mechanical ventilation for at least 24 hours. We measured clinical characteristics, BTMs, and BMD during admission and 1 year after ICU discharge. We compared change in BMD to age- and sex-matched control subjects from the Geelong Osteoporosis Study.

MEASUREMENTS AND MAIN RESULTS

Sixty-six patients completed BMD testing. BMD decreased significantly in the year after critical illness at both femoral neck and anterior-posterior spine sites. The annual decrease was significantly greater in the ICU cohort compared with matched control subjects (anterior-posterior spine, -1.59%; 95% confidence interval, -2.18 to -1.01; P < 0.001; femoral neck, -1.20%; 95% confidence interval, -1.69 to -0.70; P < 0.001). There was a significant increase in 10-year fracture risk for major fractures (4.85 ± 5.25 vs. 5.50 ± 5.52; P < 0.001) and hip fractures (1.57 ± 2.40 vs. 1.79 ± 2.69; P = 0.001). The pattern of bone resorption markers was consistent with accelerated bone turnover.

CONCLUSIONS

Critically ill individuals experience a significantly greater decrease in BMD in the year after admission compared with population-based control subjects. Their bone turnover biomarker pattern is consistent with an increased rate of bone loss.

Changes in Nonosteoporotic Bone Density and Subsequent Fractures in Women

OBJECTIVES

Osteopenia is considerably more common than osteoporosis and accounts for most of the fracture burden in women older than 50 years. It is uncertain when to initiate treatment in osteopenia. We sought to determine in women with osteopenia what effect transitioning to lower categories had on subsequent fracturing.

METHODS

We surveyed 1150 women from office-based practices who had initial normal or osteopenic bone mineral densities (BMDs) and who were retested after 5.75 years. We classified categories related to baseline T scores as follows: normal (>-1.0), mild osteopenia (-1.0 to -1.49), moderate osteopenia (-1.5 to -1.99), and severe osteopenia (-2.0 to -2.49). We determined during a 9.6-year follow-up period the fracture occurrence in those who maintained their initial category status or transitioned into lower categories.

RESULTS

Transitioning to lower categories was not significantly different among baseline osteopenic categories but significantly more than normal baseline BMDs. Total fractures, individuals fracturing, and major fractures were significantly more, with baseline T scores of ≤-1.5 (<0.001). Although only 10.2% transitioned to osteoporosis, 90.5% of these transitions occurred with baseline T scores ≤-1.5 and accounted for significantly more fractures than baseline T scores of >-1.5.

CONCLUSIONS

Most subsequent fractures and transitions to osteoporosis occurred with baseline T scores ≤-1.5. Clinical risk factors need to be used to determine at what T score threshold treatment would be cost effective.

Tapered vs Cylindrical Stem Fixation in a Model of Femoral Bone Deficiency in Revision Total Hip Arthroplasty

BACKGROUND

Distal fixation achieved with a tapered stem design has demonstrated favorable clinical results in revision total hip arthroplasty in the setting of severe bone defects. However, stem subsidence is common with this stem design.

PURPOSE

The purpose of this study is to compare the initial fixation stability of a tapered stem design to a fully porous-coated cylindrical stem design in a model of severe femoral bone deficiency.

METHODS

Tapered and cylindrical stems (n = 8) were implanted into a model femur with progressively shorter segments for fixation (9, 6, or 3 cm). The stems were axially loaded, and the force to produce subsidence was recorded.

RESULTS

Average loads to produce 150 μm of displacement with a 3-cm segment were higher for the tapered stem (393 N vs 221 N, P < .01). No difference was observed in the 6- or 9-cm models. Average loads to produce failure (>4-mm subsidence) were also higher for tapered stems with a 3-cm segment (1574 N vs 500 N, P < .0001). A regression analysis determined the minimum segment length of 1.5-2.5 cm to obtain stable fixation with a tapered stem design (R(2) = 0.78, P < .001).

CONCLUSIONS

Tapered stems required higher loads to produce subsidence than cylindrical stems in a revision THA model. Revision tapered stems require a minimum intact segment of 1.5-2.5 cm to obtain adequate initial fixation stability. Revision tapered stems have superior initial fixation stability to cylindrical stems in the setting of severe bone loss.

Hip Fracture Types in Canadian Men and Women Change Differently with Age: A Population-Level Analysis

BACKGROUND

We have previously reported a gender difference in the occurrence of hip fracture type with age in our local population. In the current report, we have explored this phenomenon in a Canadian population using five years of data from a national administrative database. We have compared community-dwelling and institutionalized individuals to determine if frailty is important and has a differential effect on the type of hip fracture experienced.

METHODS

Hospitalization records from 2005 to 2009, in which the most responsible diagnosis, that is the diagnosis causing the admission to hospital, was a hip fracture, were obtained from the Discharge Abstract Database of the Canadian Institute for Health Information. Hip fracture type was identified using the Canadian Classification of Health Interventions and the International Classification of Diseases 10th Revision, Canada (ICD-10-CA). Hip fracture proportions were calculated for the study period and stratified by age group and sex.

RESULTS

The relative proportion of intertrochanteric fractures in women rose from 35% in the youngest group (55-59 years) to 51% in the oldest group (84+ years; P < 0.0001). In men, the proportions remain relatively stable (47% and 44%, respectively). Community and institutionalized patients showed the same pattern.

CONCLUSIONS

The change in the proportion of the two hip fracture types that occur in women but not men may point to differences in the etiology and consequently the approaches to prevention for the two fracture types. Level of frailty did not seem to be important.

Comparison of Speed of Sound Measures Assessed by Multisite Quantitative Ultrasound to Bone Mineral Density Measures Assessed by Dual-Energy X-Ray Absorptiometry in a Large Canadian Cohort: the Canadian Multicentre Osteoporosis Study (CaMos)

Dual-energy X-ray absorptiometry (DXA) is an important tool for the estimate of fracture risk through the measurement of bone mineral density (BMD). Similarly, multisite quantitate ultrasound can prospectively predict future fracture through the measurement of speed of sound (SOS). This investigation compared BMD (at the femoral neck, total hip, and lumbar spine) and SOS measures (at the distal radius, tibia, and phalanx sites) in a large sample of randomly-selected and community-based individuals from the Canadian Multicentre Osteoporosis Study. Furthermore, mass, height, and age were also compared with both measures. There were 4123 patients included with an age range of 30-96.8 yr. Pearson product moment correlations between BMD and SOS measures were low (0.21-0.29; all p<0.001), irrespective of site. Mass was moderately correlated with BMD measures (0.40-0.58; p<0.001), but lowly correlated with SOS measures (0.03-0.13; p<0.05). BMD and SOS were negatively correlated to age (-0.17 to -0.44; p<0.001). When regression analyses were performed to predict SOS measures at the 3 sites, the models predicted 20%-23% of the variance, leaving 77%-80% unaccounted for. The SOS measures in this study were found to be largely independent from BMD measures. In areas with no or limited access to DXA, the multisite quantitative ultrasound may act as a valuable tool to assess fracture risk. In locales with liberal access to DXA, the addition of SOS to BMD and other clinical risk factors may improve the identification of those patients at high risk for future fracture.

Fracture prediction from repeat BMD measurements in clinical practice

We investigated whether repeat BMD measurements in clinical populations are useful for fracture risk assessment. We report that repeat BMD measurements are a robust predictor of fracture in clinical populations; this is not affected by preceding BMD change or recent osteoporosis therapy.

INTRODUCTION

In clinical practice, many patients selectively undergo repeat bone mineral density (BMD) measurements. We investigated whether repeat BMD measurements in clinical populations are useful for fracture risk assessment and whether this is affected by preceding change in BMD or recent osteoporosis therapy.

METHODS

We identified women and men aged ≥ 50 years who had a BMD measurement during 1990-2009 from a large clinical BMD database for Manitoba, Canada (n = 50,215). Patient subgroups aged ≥ 50 years at baseline with repeat BMD measures were identified. Data were linked to an administrative data repository, from which osteoporosis therapy, fracture outcomes, and covariates were extracted. Using Cox proportional hazards models, we assessed covariate-adjusted risk for major osteoporotic fracture (MOF) and hip fracture according to BMD (total hip, lumbar spine, femoral neck) at different time points.

RESULTS

Prevalence of osteoporosis therapy increased from 18 % at baseline to 55 % by the fourth measurement. Total hip BMD was predictive of MOF at each time point. In the patient subgroup with two repeat BMD measurements (n = 13,481), MOF prediction with the first and second measurements was similar: adjusted-hazard ratio (HR) per SD 1.45 (95 % CI 1.34-1.56) vs. 1.64 (95 % CI 1.48-1.81), respectively. No differences were seen when the second measurement results were stratified by preceding change in BMD or osteoporosis therapy (both p-interactions >0.2). Similar results were seen for hip fracture prediction and when spine and femoral neck BMD were analyzed.

CONCLUSION

Repeat BMD measurements are a robust predictor of fracture in clinical populations; this is not affected by preceding BMD change or recent osteoporosis therapy.

Bone Mineral Density as a Predictor of Subsequent Wrist Fractures: Findings From the Women's Health Initiative Study

CONTEXT

Wrist fractures are common among postmenopausal women. Associations of bone mineral density (BMD) and 10-year predicted risk of major osteoporotic fracture (MOF) with wrist fractures are poorly characterized.

OBJECTIVE

The objective was to examine associations between the Fracture Risk Assessment Tool (FRAX)-predicted risk of MOF, BMD, BMD change, and wrist fracture.

DESIGN

This was a prospective observational study with a mean follow-up of 8.5 years.

SETTING

This study included 40 US centers.

PARTICIPANTS

A total of 11 392 participants from the Women's Health Initiative BMD Cohort aged 50-79 years at baseline were included in this study.

INTERVENTIONS

None.

MAIN OUTCOME

The goal was to measure incident wrist fracture.

RESULTS

A FRAX-predicted MOF risk ≥9.3% identified 17% of the women aged <65 years who subsequently experienced wrist fracture. Each one standard deviation lower BMD was associated with higher wrist fracture risk, with adjusted hazard ratio (95% confidence interval) of 1.66 (1.42-1.93) for femoral neck (FN) BMD and 1.45 (1.28-1.64) for lumbar spine BMD. Compared with FN BMD T score ≥ -1.0, wrist fracture adjusted hazard ratios (95% confidence interval) were: 1.51 (1.06-2.16) for a T score between -1.01 and -1.49; 1.93 (1.36-2.72) for T score between -1.50 and -1.99; 2.52 (1.77-3.60) for a T score between -2.00 and -2.49; and 2.65 (1.78-3.95) for a T score ≤ -2.5. Decrease in FN BMD between baseline and year 3 was associated with increased risk of subsequent wrist fracture; however, change in lumbar spine BMD was not.

CONCLUSIONS

Lumbar spine and femoral neck BMDs were associated with incident wrist fracture, but the FRAX threshold recommended to identify screening candidates did not identify the majority of women who subsequently experienced wrist fracture. Improved understanding of determinants of wrist fractures is warranted.

Denosumab and teriparatide transitions in postmenopausal osteoporosis (the DATA-Switch study): extension of a randomised controlled trial

BACKGROUND

Unlike most chronic diseases, osteoporosis treatments are generally limited to a single drug at a fixed dose and frequency. Nonetheless, no approved therapy is able to restore skeletal integrity in most osteoporotic patients and the long-term use of osteoporosis drugs is controversial. Thus, many patients are treated with the sequential use of two or more therapies. The DATA study showed that combined teriparatide and denosumab increased bone mineral density more than either drug alone. Discontinuing teriparatide and denosumab, however, results in rapidly declining bone mineral density. In this DATA-Switch study, we aimed to assess the changes in bone mineral density in postmenopausal osteoporotic women who transitioned between treatments.

METHODS

This randomised controlled trial (DATA-Switch) is a preplanned extension of the denosumab and teriparatide administration study (DATA), in which 94 postmenopausal osteoporotic women were randomly assigned to receive 24 months of teriparatide (20 mg daily), denosumab (60 mg every 6 months), or both drugs. In DATA-Switch, women originally assigned to teriparatide received denosumab (teriparatide to denosumab group), those originally assigned to denosumab received teriparatide (denosumab to teriparatide group), and those originally assigned to both received an additional 24 months of denosumab alone (combination to denosumab group). Bone mineral density at the spine, hip, and wrist were measured 6 months, 12 months, 18 months, and 24 months after the drug transitions as were biochemical markers of bone turnover. The primary endpoint was the percent change in posterior-anterior spine bone mineral density over 4 years. Between-group changes were assessed by one-way analysis of variance in our modified intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00926380.

FINDINGS

Between Sept 27, 2011, and Jan 28, 2013, eligible women from the DATA study were enrolled into DATA-Switch. Of 83 potential enrollees from the DATA study, 77 completed at least one post-baseline visit. After 48 months, the primary outcome of mean spine bone mineral density increased by 18·3% (95% CI 14·9-21·8) in 27 women in the teriparatide to denosumab group, 14·0% (10·9-17·2) in 27 women the denosumab to teriparatide group, and 16·0% (14·0-18·0) in 23 women in the combination to denosumab group, although this increase did not differ significantly between groups (for between-group comparisons, p=0·13 for the teriparatide to denosumab group vs the denosumab to teriparatide group, p=0·30 for the teriparatide to denosumab group vs the combination to denosumab group, and p=0·41 for the denosumab to teriparatide group vs the combination to denosumab group). For the bone mineral density secondary outcomes, total hip bone mineral density increased more in the teriparatide to denosumab group (6·6% [95% CI 5·3-7·9]) than in the denosumab to teriparatide group (2·8% [1·3-4·2], p=0·0002), but had the greatest increase in the combination to denosumab group (8·6% [7·1-10·0]; p=0·0446 vs the teriparatide to denosumab group, p<0·0001 vs the denosumab to teriparatide group). Similarly, femoral neck bone mineral density increased more in the teriparatide to denosumab group (8·3% [95% CI 6·1-10·5]) and the combination to denosumab group (9·1% [6·1-12·0]) than in the denosumab to teriparatide group (4·9% [2·2-7·5]; p=0·0447 for teriparatide to denosumab vs denosumab to teriparatide, p=0·0336 for combination to denosumab vs denosumab to teriparatide). Differences between the combination to denosumab group and the teriparatide to denosumab group did not differ significantly (p=0·67). After 48 months, radius bone mineral density was unchanged in the teriparatide to denosumab group (0·0% [95% CI -1·3 to 1·4]), whereas it decreased by -1·8% (-5·0 to 1·3) in the denosumab to teriparatide group, and increased by 2·8% (1·2-4·4) in the combination to denosumab group (p=0·0075 for the teriparatide to denosumab group vs the combination to denosumab group; p=0·0099 for the denosumab to teriparatide group vs the combination to denosumab group). One participant in the denosumab to teriparatide group had nephrolithiasis, classified as being possibly related to treatment.

INTERPRETATION

In postmenopausal osteoporotic women switching from teriparatide to denosumab, bone mineral density continued to increase, whereas switching from denosumab to teriparatide results in progressive or transient bone loss. These results should be considered when choosing the initial and subsequent management of postmenopausal osteoporotic patients.

FUNDING

Amgen, Eli Lilly, and National Institutes of Health.

Relationship between pretreatment rate of bone loss and bone density response to once-yearly ZOL: HORIZON-PFT extension study

Several studies have shown that high bone turnover is associated with greater rates of bone loss and greater bone mineral density (BMD) response to antiresorptive therapy in postmenopausal osteoporosis. However, it is not known whether greater rates of bone loss before therapy are associated with greater BMD response to antiresorptive therapy. In the HORIZON-PFT study and its extension, one group of women who were randomized to receive placebo for 3 years (years 1, 2, and 3) were then switched to zoledronic acid (ZOL) 5 mg annually for up to three injections (years 4, 5, and 6, P3Z3 arm) (n = 1223). We measured total hip BMD at baseline, 1, 2, and 3 years on placebo and at 4.5 and 6 years on ZOL. The procollagen type I N-terminal propeptide (PINP) was measured at 3, 4.5, and 6 years. By design, not all subjects were followed for as long as 6 years, so this analysis focused on the results at 4.5 years. Those with the largest loss in total hip BMD on placebo in years 0 to 3 had the largest gain during ZOL (years 3 to 4.5): (r = -0.39, p < 0.0001). The change in total hip BMD in years 0 to 3 on placebo was related to the serum PINP at the end of the 3-year period (r = -0.24, p < 0.0001). The change in total hip BMD on ZOL from year 3 to 4.5 was related to the serum PINP at the end of the 3-year period (r = 0.26, p < 0.0001). We conclude that BMD response to ZOL is greater in postmenopausal women who had larger loss before treatment. This association may result from higher bone turnover being associated with both greater bone loss on placebo and greater BMD response to ZOL.