Pre-treatment bone turnover does not influence the level of the response to alendronate in postmenopausal osteoporosis at the bone tissue level

PURPOSE

The main effect of anti-resorptive agents such as bisphosphonates is a reduction of bone resorption, with a consequent marked decrease of bone turnover. This post-hoc analysis investigated the changes of histomorphometric parameters of bone turnover after alendronate (ALN), according to the baseline turnover.

METHODS

Ninety postmenopausal women underwent a transiliac bone biopsy before and after 6 (n = 44) or 12 (n = 46) months of treatment with ALN (70 mg/week). The dynamic parameters reflecting the bone formation and bone turnover were mineralizing surface (MS/BS; %), bone formation rate (BFR/BS; μm3/μm2/d), and activation frequency (Ac.f; /yr). Biochemical markers sPINP and the sCTX were assessed before treatment and after 3, 6, and 12 months. Subjects were divided into quartiles based on the baseline values of BFR/BS.

RESULTS

At baseline, MS/BS and Ac.f were significantly different (p < 0.0001) among the BFR quartiles. sCTX and sP1NP were not significantly different among quartiles. After ALN treatment, MS/BS was not significantly different among quartiles but Ac.f remained significantly lower in the first quartile compared to the third and fourth ones (p < 0.03). The absolute value of the difference between pre- and post-treatment significantly correlated with the baseline BFR/BS but when expressed in percent of the baseline value, the magnitude of the diminutions of MS/BS, Ac.f, sCTX, and sP1NP was similar in the four baseline BFR quartiles.

CONCLUSION

The percentage response to ALN appeared independent of the baseline level of bone turnover. After treatment, the bone turnover tended to be similar in all BFR quartiles. This analysis investigated the influence of baseline turnover measured by bone histomorphometry on the effect of alendronate. When expressed in percent of pre-treatment values, the decreases of histomorphometric parameters and biochemical markers of bone turnover were independent of the baseline turnover.

Previous fracture and subsequent fracture risk: a meta-analysis to update FRAX

A large international meta-analysis using primary data from 64 cohorts has quantified the increased risk of fracture associated with a previous history of fracture for future use in FRAX.

INTRODUCTION

The aim of this study was to quantify the fracture risk associated with a prior fracture on an international basis and to explore the relationship of this risk with age, sex, time since baseline and bone mineral density (BMD).

METHODS

We studied 665,971 men and 1,438,535 women from 64 cohorts in 32 countries followed for a total of 19.5 million person-years. The effect of a prior history of fracture on the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture, and hip fracture alone was examined using an extended Poisson model in each cohort. Covariates examined were age, sex, BMD, and duration of follow-up. The results of the different studies were merged by using the weighted β-coefficients.

RESULTS

A previous fracture history, compared with individuals without a prior fracture, was associated with a significantly increased risk of any clinical fracture (hazard ratio, HR = 1.88; 95% CI = 1.72-2.07). The risk ratio was similar for the outcome of osteoporotic fracture (HR = 1.87; 95% CI = 1.69-2.07), major osteoporotic fracture (HR = 1.83; 95% CI = 1.63-2.06), or for hip fracture (HR = 1.82; 95% CI = 1.62-2.06). There was no significant difference in risk ratio between men and women. Subsequent fracture risk was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any clinical fracture (14%), osteoporotic fracture (17%), and for hip fracture (33%). The risk ratio for all fracture outcomes related to prior fracture decreased significantly with adjustment for age and time since baseline examination.

CONCLUSION

A previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by BMD. The effect is similar in men and women. Its quantitation on an international basis permits the more accurate use of this risk factor in case finding strategies.

Value of rare diseases reference centers: impact on diagnosis and access to specialized care in fibrous dysplasia of bone

INTRODUCTION

Reference Centers and Rare Disease Health Networks aim to improve the management of patients with rare diseases. The French reference center for Fibrous Dysplasia was certified in 2006.

OBJECTIVE

The objective of our study was to assess the effectiveness of our reference center since its constitution.

METHODS

In a retrospective cohort study, we compared the activity of our center, including the time elapsed between access to the center and the diagnostic delay of patients with Fibrous Dysplasia between two periods, 1994-2006 (before certification) and 2007-2019 (after certification). Data were extracted from patients' records (Easily®). Wilcoxon and Fisher tests were performed, using R®.

RESULTS

Our cohort included 527 patients with Fibrous Dysplasia/Mc Cune Albright syndrome. The activity of the Fibrous Dysplasia center increased from 139 patients in the first period (1994-2006) to an additional 388 patients for the second period (2007-2019). Mean time elapsed to diagnosis of Fibrous Dysplasia was 1.5 years before 2007 and 1.9 years after 2007 (p = 0.12). Diagnosis was made before referral in over 80% of patients. There was a non-significant decrease in the number of patients with delayed diagnosis: 37 patients (44%) in the first period had a diagnostic delay and 94 patients (33%) in the second period (p = 0.07). Patients were referred to our center on average 6.8 years (before 2007) and 7.9 years (after 2007) after their diagnosis (p = 0.77).

CONCLUSION

Healthcare organization with reference centers significantly impacted the management of patients with Fibrous Dysplasia/Mc Cune Albright syndrome, with a substantial increase in the activity of our center, that roughly tripled since certification. This healthcare organization was also associated with a trend toward decreasing diagnostic delay. However, diagnostic delay affected more than a third of patients and the time to access to the center remained extended (≈7-8 years after diagnosis). The current challenge lies in informing primary care providers and patients about education to rare diseases and existence of reference centers for earlier and more effective specialized management.

Denosumab use in bone fibrous dysplasia refractory to bisphosphonate: A retrospective multicentric study

INTRODUCTION

Increased RANKL expression is observed in the bone tissue of fibrous dysplasia of bone/McCune-Albright syndrome (FD/MAS). In one animal model of FD/MAS, the inhibition of RANKL reduced tumor volume. A beneficial effect of denosumab on pain in patients refractory to bisphosphonates has been reported, but without systematic quantification of pain improvement. This work describes the clinical experience of our group on the efficacy on pain of denosumab treatment, along with safety, in FD/MAS patients refractory to bisphosphonates.

MATERIALS AND METHODS

We have conducted a retrospective multicenter study in 6 academic rheumatology centers in France. We have collected patients and FD/MAS characteristics, duration of prior exposure to bisphosphonates, denosumab treatment modalities (dosage - administration regimen - number of courses); evolution of pain evaluated by Visual Analogic Scale (VAS).

RESULTS

13 patients were included (10 women and 3 men) 45 years on average, 5 MAS, 4 monostotic and 4 polyostotic forms. The average duration post-diagnosis of FD/MAS was 25 years and the mean duration of prior exposure to bisphosphonates was 4.7 years. Pain could be analyzed in 7 patients, showing a significant improvement from a mean VAS of 7.8 to 2.9 (-4.9 points, p = 0.003). In one patient with fronto-orbital FD/MAS, a 30 % decrease in lesional volume, assessed by MRI, was observed within 6 months of treatment, that was sustained over the following 12 months. Treatment regimens were heterogeneous. No hypercalcemia was observed after treatment cessation and the clinical tolerance was good.

DISCUSSION

This study suggests that denosumab reduces pain in patients with DF/MAS refractory to bisphosphonates, and quantifies this improvement for the first time in a multicenter study. In our cohort, no patients who discontinued denosumab developed hypercalcemia and clinical tolerance was overall good. This study also provides encouraging data regarding lesion volume control. Further controlled studies are required to determine the place and modalities of the denosumab treatment of FD/MAS.

CONCLUSION

Denosumab significantly decreased pain in FD/MAS refractory to bisphosphonate. This study paves the way for a randomized clinical trial to validate and standardize the prescription of denosumab in FD/MAS.

Murine models of posterolateral spinal fusion: A systematic review

BACKGROUND

Rodent models are commonly used experimentally to assess treatment effectiveness in spinal fusion. Certain factors are associated with better fusion rates. The objectives of the present study were to report the protocols most frequently used, to evaluate factors known to positively influence fusion rate, and to identify new factors.

METHOD

A systematic literature search of PubMed and Web of Science found 139 experimental studies of posterolateral lumbar spinal fusion in rodent models. Data for level and location of fusion, animal strain, sex, weight and age, graft, decortication, fusion assessment and fusion and mortality rates were collected and analyzed.

RESULTS

The standard murine model for spinal fusion was male Sprague Dawley rats of 295g weight and 13 weeks' age, using decortication, with L4-L5 as fusion level. The last two criteria were associated with significantly better fusion rates. On manual palpation, the overall mean fusion rate in rats was 58% and the autograft mean fusion rate was 61%. Most studies evaluated fusion as a binary on manual palpation, and only a few used CT and histology. Average mortality was 3.03% in rats and 1.56% in mice.

CONCLUSIONS

These results suggest using a rat model, younger than 10 weeks and weighing more than 300 grams on the day of surgery, to optimize fusion rates, with decortication before grafting and fusing the L4-L5 level.

The disability associated with hand osteoarthritis is substantial in a cohort of post-menopausal women: the QUALYOR study

OBJECTIVES

Our primary aims were to assess current prevalence of HOA and the disability associated with this condition, in the group usually most affected, i.e., women older than 55.

METHODS

We performed hand radiographs, clinical examination, grip strength measurement, AUSCAN and COCHIN questionnaires in a cohort of postmenopausal women aged at least 55. Radiographic hand OA (RHOA) was defined as at least 2 affected joints among 30, grading 2 or more using the Kellgren Lawrence score but without any HOA symptom. Symptomatic HOA (OA ACR) was defined according to ACR criteria for hand OA. Moderate to severe symptomatic HOA was defined as having OA ACR and AUSCAN total score of >43/100.

RESULTS

We enrolled 1,189 participants. The mean age was 71.7 years. Inter-reader reliability of radiographs reading was good (ICC = 0.86) and intra-reader reliability was excellent (ICC = 0.97). Among the 1,189 women, 333 (28.0%) had RHOA, 482 (40.5%) patients fulfilled the ACR criteria for symptomatic HOA and 82 of these (17% of OA ACR population) had moderate to severe symptomatic HOA. The prevalence of symptomatic erosive osteoarthritis was 11.8%. Mean AUSCAN and Cochin scores were higher and grip strength lower in patients with symptomatic HOA compared to patient without HOA. Differences were more noticeable in patients with moderate to severe HOA.

CONCLUSIONS

We have assessed disability associated with HOA in greater detail than previously and found that a third of postmenopausal women had RHOA, two fifths had symptomatic HOA and one sixth of symptomatic patients had moderate to severe HOA related disability and a tenth had symptomatic erosive osteoarthritis, representing a substantial burden of disease in our population-based cohort.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

POS0499 A NEW SERUM ASSAY MEASURING SYNOVIAL TURNOVER IN RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is characterized by synovial tissue (ST) inflammation leading to pain, joint destruction, impaired mobility and ultimately increased morbidity and mortality. These various components of disease etiology can be monitored by pain scores and imaging technologies. Noninvasive assessment of joint tissues metabolism can be performed by measuring serum metabolites of tissue matrix turnover. Specific biochemical markers (BM) of bone and cartilage have been developed, but there is still a lack of a sensitive index of ST metabolism abnormalities, although there are early and key drivers of joint destruction.

Objectives

To develop a sensitive ELISA-based serum BM of ST turnover (SynHelix) and evaluate its performance in patients with RA.

Methods

We identified a 11 amino-acid sequence (HELIX-III) within the triple helical portion of type III collagen, a main component of ST matrix which is released during ST turnover and can be measured in the serum. A highly specific rabbit polyclonal antibody raised against the synthetic HELIX-III peptide was produced to develop a competitive ELISA. Specificity of the antibody was evaluated by competitive inhibitions with homologous sequences of type I, IV and XI collagens which are also present in ST, but in minor quantities for the two later. Immunohistochemistry analysis of human ST obtained during hip surgery was performed to investigate in situ localisation of the HELIX-III peptide. ELISA was then used to quantify serum HELIX-III fragments in two samples of patients with low (n= 40, median DAS 28: 2.1) and moderate (n=11, median DAS28: 3.5) RA activity participating in clinical trials. Levels in RA subjects were compared to sex and age-matched healthy controls randomly selected from epidemiological cohorts (n=70).

Results

The ELISA for SynHelix demonstrated adequate analytical performances with intra and interassay variations below 10 and 15%, respectively; analytical and functional limits of quantification of 0.21 and 2.5 ng/ml, respectively and dilution recovery of human serum ranging from 80 to 108%. Competitive inhibition experiments demonstrated that the antibody does not recognize HELIX-III peptide shortened or elongated by one amino-acid, indicating that immunogenicity is dependent on the presence of a neopitope resulting from the cleavage of the collagen molecule. The antibody does not recognize the homologous sequence of type I collagen, but shows significant immunoreactivity with the homologous sequences of type IV (alpha 5) and type XI (alpha 2) collagens with however a lower affinity than for type III collagen (a 2.2 and 4-fold higher concentration, respectively, is needed to displace 50% of the immune signal). Immunohistochemistry of ST tissue from RA subjects showed increased staining in the interstitial tissue and around vessels which are rich in type IV collagen. Median serum levels of SynHelix were significantly higher in patients with low (p=0027, +17%) and moderate RA activity (+220%, p=00004 vs healthy controls; +164% p=0.16 vs low RA) compared with those in age-matched controls, although CRP did not discriminate RA patients with low and moderate activity (2.2 mg/L for both groups, p=0.90). In RA subjects, serum SynHelix correlates modestly with CRP (r=0.59, p <0.0001), but not with DAS28.

Conclusion

The new SynHelix ELISA measures precisely circulating degradation fragments of Helix-III peptide-containing collagens. Serum SynHelix levels are already increased in patients with low activity RA, values correlating modestly the degree of systemic inflammation. Larger longitudinal studies are needed to further evaluate the value of SynHelix to predict disease outcome in RA.

Disclosure of Interests

Patrick Garnero: None declared, Evelyne Gineyts: None declared, Jean-Charles Rousseau: None declared, Hubert MAROTTE: None declared, Roland Chapurlat Consultant of: BMS, abbvie, Lilly, Galapagos, fresenius-Kiabi, novartis.

The global approach to rehabilitation following an osteoporotic fragility fracture: A review of the rehabilitation working group of the International Osteoporosis Foundation (IOF) committee of scientific advisors

PURPOSE

To conduct a review of the current state of the evidence for rehabilitation strategies post-fragility fracture.

METHODS

Narrative review conducted by the Rehabilitation Working Group of the International Osteoporosis Foundation Committee of Scientific Advisors characterizing the range of rehabilitation modalities instrumental for the management of fragility fractures.

RESULTS

Multi-modal exercise post-fragility fracture to the spine and hip is strongly recommended to reduce pain, improve physical function, and improve quality of life. Outpatient physiotherapy post-hip fracture has a stronger evidence base than outpatient physiotherapy post-vertebral fracture. Appropriate nutritional care after fragility fracture provides a large range of improvement in morbidity and mortality. Education increases understanding of osteoporosis which in turn increases utilization of other rehabilitation services. Education may improve other health outcomes such as pain and increase a patient's ability for self-advocacy.

CONCLUSION

Rehabilitation interventions are inter-reliant, and research investigating the interaction of exercise, nutrition, and other multi-modal therapies may increase the relevance of rehabilitation research to clinical care.

Reference microarchitectural values measured by HR-pQCT in a Franco-Swiss cohort of young adult women

Bone microarchitecture assessed by high-resolution peripheral quantitative computed tomography varies across populations of different origin. The study presents a reference dataset of microarchitectural parameters in a homogeneous group of participants aged within 22-27 range determined by a discriminant analysis of a larger cross-sectional cohort of 339 women.

INTRODUCTION

High-resolution peripheral quantitative computed tomography (HR-pQCT) non-invasively measures three-dimensional bone microarchitectural parameters and volumetric bone mineral density. Previous studies established normative reference HR-pQCT datasets for several populations, but there were few data assessed in a reference group of young women with Caucasian ethnicity living in Western Europe. It is important to obtain different specific reference dataset for a valid interpretation of cortical and trabecular microarchitecture data. The aim of our study was to find the population with the most optimal bone status in order to establish a descriptive reference HR-pQCT dataset in a young and healthy normal-weight female cohort living in a European area including Geneva, Switzerland, Lyon and Saint-Etienne, France.

METHODS

We constituted a cross-sectional cohort of 339 women aged 19-41 years with a BMI > 18 and < 30 kg/m². All participants had HR-pQCT measurements at both non-dominant distal radius and tibia sites.

RESULTS

We observed that microarchitectural parameters begin to decline before the age of 30 years. Based on a discriminant analysis, the optimal bone profile in this population was observed between the age range of 22 to 27 years. Consequently, we considered 43 participants aged 22-27 years to establish a reference dataset with median values and percentiles.

CONCLUSION

This is the first study providing reference values of HR-pQCT measurements considering specific age bounds in a Franco-Swiss female cohort at the distal radius and tibia sites.

Extent of Extraskeletal Manifestations of Fibrous Dysplasia/McCune-Albright Syndrome in Patients with Mazabraud's Syndrome

Mazabraud's syndrome (MZB) is a rare condition in which fibrous dysplasia of bone/the McCune-Albright syndrome (FD/MAS) co-exists with intramuscular myxomas. Both FD and the myxomas harbor the GNAS-mutation. Recent studies have shown that extraskeletal, GNAS-related features are associated with a more severe phenotype of FD/MAS. However, patients with MZB are often only seen by orthopedic surgeons. We therefore evaluated MZB patients seen in tertiary referral centers from the Netherlands (LUMC), USA (National Institutes of Health) and France (INSERM UMR 1033 (Lyos), Hôpital Edouard Herriot). All FD/MAS patients known in these centers with an additional diagnosis of a myxoma were included. Demographic information and data on disease extent and extraskeletal manifestations of FD/MAS such as precocious puberty (PP) or café-au-lait patches (CAL) were retrieved from patient's medical records. Thirty MZB patients were included: 20 women (67%) and 10 men (33%). Patients received a diagnosis of MZB (median 42 years, range 16-19) significantly later than the diagnosis of FD/MAS (median 30 years, range 0-60), p < 0.01. Twenty-six patients were diagnosed with polyostotic disease (87%). In 97% the myxoma was located near the skeletal FD lesion. The combination of MZB and MAS was made in 13 patients in whom PP (n = 7), CAL (n = 7), GH-excess (n = 3) and hyperthyroidism (n = 3) were present. Other extraskeletal features were (multinodular) goiter (n = 2) and thyroid cysts (n = 1). Furthermore, in this cohort of patients with MZB several (pre-)malignant tumors were observed; ductal carcinoma in situ of the breast in 3 patients (10%), breast cancer in 1 patient (3.3%), intra pancreatic mucinous neoplasms in 3 patients (10%) and liver adenomas in 2 patients (6.6%). A total of 47% of patients with MZB had an additional extraskeletal feature such as an endocrinopathy. In MZB, 87% of patients suffer from polyostotic FD, 43% of patients have extraskeletal GNAS-features such as an hyperfunctioning endocrinopathy and 30% (pre-)malignant tumors. We therefore advocate that MZB patients should undergo a complete screening and long-term follow-up for extent of bone disease, but also extraskeletal GNAS features of FD/MAS.

The clinical application of high-resolution peripheral computed tomography (HR-pQCT) in adults: state of the art and future directions

High-resolution peripheral computed tomography (HR-pQCT) was developed to image bone microarchitecture in vivo at peripheral skeletal sites. Since the introduction of HR-pQCT in 2005, clinical research to gain insight into pathophysiology of skeletal fragility and to improve prediction of fractures has grown. Meanwhile, the second-generation HR-pQCT device has been introduced, allowing novel applications such as hand joint imaging, assessment of subchondral bone and cartilage thickness in the knee, and distal radius fracture healing. This article provides an overview of the current clinical applications and guidance on interpretation of results, as well as future directions. Specifically, we provide an overview of (1) the differences and reference data for HR-pQCT variables by age, sex, and race/ethnicity; (2) fracture risk prediction using HR-pQCT; (3) the ability to monitor response of anti-osteoporosis therapy with HR-pQCT; (4) the use of HR-pQCT in patients with metabolic bone disorders and diseases leading to secondary osteoporosis; and (5) novel applications of HR-pQCT imaging. Finally, we summarize the status of the application of HR-pQCT in clinical practice and discuss future directions. From the clinical perspective, there are both challenges and opportunities for more widespread use of HR-pQCT. Assessment of bone microarchitecture by HR-pQCT improves fracture prediction in mostly normal or osteopenic elderly subjects beyond DXA of the hip, but the added value is marginal. The prospects of HR-pQCT in clinical practice need further study with respect to medication effects, metabolic bone disorders, rare bone diseases, and other applications such as hand joint imaging and fracture healing. The mostly unexplored potential may be the differentiation of patients with only moderately low BMD but severe microstructural deterioration, which would have important implications for the decision on therapeutical interventions.

Discriminating value of HR-pQCT for fractures in women with similar FRAX scores: A substudy of the FRISBEE cohort

Areal bone mineral density (aBMD) has a low sensitivity to identify women at high fracture risk. The FRAX algorithm, by combining several clinical risk factors, might improve fracture prediction compared to aBMD alone. Several micro-architectural and biomechanical parameters which can be measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) are associated with fracture risk. HR-pQCT in combination or not with finite element analysis (FEA) may be used to improve bone strength prediction. Our aim was to assess whether HR-pQCT measurements (densities, cortical and trabecular microarchitecture, biomechanical proprieties assessed by FEA) had an added value in predicting fractures in a subgroup of women belonging to the Belgian FRISBEE cohort. One hundred nineteen women who sustained a fracture (aged 60 to 85 years) during the initial follow-up of our cohort had a radius and tibia examination by HR-pQCT and were compared with controls matched for their FRAX score at baseline. We found that low distal radius total (OR = 1.41 [1.07-1.86] per SD, p < 0.05) and trabecular densities (OR = 1.45 [1.10-1.90], p < 0.01), trabecular number (OR = 1.32 [1.01-1.72], p < 0.05), intra individual distribution of separation (OR = 0.73 [0.54-0.99], p < 0.05) as several FEA parameters were significantly associated with fractures. At the distal tibia, impaired cortical density (OR = 1.32 [1.03-1.70] per SD, p < 0.05) and thickness (OR = 1.29 [1.01-1.63], p < 0.05) and apparent modulus (OR = 1.30 [1.01-1.66], p < 0.05) were significantly correlated with fractures. A low ultra distal radial aBMD (UDR) measured at the time of HR-pQCT was significantly associated with fractures (OR = 1.67 [1.22-2.28], p < 0.01). Women from both groups were followed further after the realization of the HR-pQCT and 46 new fractures were registered. In this second part of the study, low UDR aBMD (OR = 1.66 [1.18-2.35], p < 0.01), total (OR = 1.48 [1.08-2.03], p < 0.05), cortical (OR = 1.40 [1.04-1.87], p < 0.05) and trabecular (OR = 1.37 [1.01-1.85], p < 0.05) densities or apparent modulus (OR = 1.49 [1.07-2.05], p < 0.05) at the radius were associated with a significant increase of fracture risk. At the tibia, only the cortical density was significantly associated with the fracture risk (OR = 1.34 [1.02-2.76], p < 0.05). These results confirm the interest of HR-pQCT measurements for the evaluation of fracture risk, also in women matched for their baseline FRAX score. They also highlight that UDR aBMD contains pertinent information.

Randomized, controlled trial to assess the safety and efficacy of odanacatib in the treatment of men with osteoporosis

Odanacatib (ODN) was investigated as an osteoporosis treatment in 292 men. Compared with placebo, odanacatib improved bone mineral density and led to sustained bone resorption decreases while producing relatively little bone formation reduction that leveled off with time. However, increased risk of stroke in another study stopped further odanacatib development.

INTRODUCTION

ODN, a selective oral cathepsin K inhibitor, was in development for osteoporosis treatment. This phase 3, double-blind, randomized, placebo-controlled, 24-month study investigated ODN safety and efficacy in men with osteoporosis.

METHODS

Men with idiopathic osteoporosis or osteoporosis due to hypogonadism and a lumbar spine or hip (total hip [TH], femoral neck [FN], or trochanter) bone mineral density (BMD) T-score of ≤ - 2.5 to ≥ - 4.0 without prior vertebral fracture or ≤ - 1.5 to ≥ - 4.0 with one prior vertebral fracture were randomized (1:1) to once-weekly ODN 50 mg or placebo. All received 5600 IU vitamin D₃ weekly and calcium supplementation as needed (≥ 1200 mg daily). The primary efficacy outcome was changed from baseline in lumbar spine BMD versus placebo.

RESULTS

Overall, 292 men, mean age 68.8 years, were randomly assigned to ODN or placebo. Versus placebo, ODN increased BMD from baseline at the lumbar spine, TH, FN, and trochanter by 5.6%, 2.0%, 1.7%, and 2.1%, respectively (all p < 0.01), and decreased uNTx/Cr (68%, p < 0.001), sCTx (77%, p < 0.001), sP1NP (16%, p = 0.001), and sBSAP (8%, p = 0.019). The between-group bone formation marker decrease peaked at 3 months, then returned toward baseline. The safety profile, including cardiovascular events, was similar between groups.

CONCLUSION

Though a promising osteoporosis therapy for men, ODN development was discontinued due to increased risk of stroke in the LOFT phase 3 trial.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01120600 (registered May 11, 2010).

Rapid Progression of Aortic Calcification in Older Men with Low Appendicular Lean Mass and Poor Physical Function

OBJECTIVES

Assessment of the progression of abdominal aortic calcification (AAC) may be a surrogate marker of the impact of physical function on cardiovascular risk. Our aim was to assess the risk of rapid AAC progression in older men with low relative appendicular lean mass (RALM) and poor physical function.

DESIGN

Prospective cohort study.

SETTING

Community-dwelling older men.

PARTICIPANTS

621 men aged 50-85 followed prospectively (baseline, 3 and 7.5 years).

MEASUREMENTS

Body composition was assessed by DXA. Poor physical function was defined as incapacity to perform ≥1 of 5 clinical tests (balance, muscle strength). AAC was assessed using Kauppila's semiquantitative score. Reclassification improvement was assessed by comparing the areas under the curve (AUC) using DeLong's method.

RESULTS

Rapid AAC progression (>0.6 point/year) was found in 168 men (27.1%). After adjustment for confounders including baseline AAC, the risk of rapid AAC progression increased with lower RALM (OR=1.42/SD, 95%CI: 1.09-1.86, p<0.01) and was higher in the lowest (<7.5kg/m2) vs. highest (>8.6kg/m2) quartile (OR=2.15, 95%CI: 1.17-3.95, p<0.01). Poor physical performance was associated with rapid AAC progression (OR=2.76, 95%CI: 1.48-5.91, p<0.005). Low RALM (<7.84kg/m2 defined using Youden's index) and poor physical function contributed to the risk of rapid AAC progression jointly. Men who had low RALM and poor physical function had higher risk of rapid AAC progression vs. men without these traits (OR=4.66, 95%CI: 1.72-12.62, p<0.05). RALM and physical function improved the identification of men with rapid AAC progression (DAUC=0.026, 95%CI: 0.005-0.046, p<0.05) after adjustment for confounders including baseline AAC score.

CONCLUSIONS

Low RALM and poor physical function are associated with higher risk of rapid AAC progression and possibly represent another measure of cardiovascular risk.

Determining individual trajectories of joint space loss: improved statistical methods for monitoring knee osteoarthritis disease progression

OBJECTIVES

Knee osteoarthritis (KOA) progression is frequently monitored by calculating the change in knee joint space width (JSW) measurements. Such differences are small and sensitive to measurement error. We aimed to assess the utility of two alternative statistical modelling methods for monitoring KOA.

MATERIAL AND METHODS

We used JSW on radiographs from both the control arm of the Strontium Ranelate Efficacy in Knee Osteoarthritis trial (SEKOIA), a 3-year multicentre, double-blind, placebo-controlled phase three trial, and the Osteoarthritis Initiative (OAI), an open-access longitudinal dataset from the USA comprising participants followed over 8 years. Individual estimates of annualised change obtained from frequentist linear mixed effect (LME) and Bayesian hierarchical modelling, were compared with annualised crude change, and the association of these parameters with change in WOMAC pain was examined.

RESULTS

Mean annualised JSW changes were comparable for all estimates, a reduction of around 0.14 mm/y in SEKOIA and 0.08 mm/y in OAI. The standard deviation (SD) of change estimates was lower with LME and Bayesian modelling than crude change (SEKOIA SD = 0.12, 0.12 and 0.21 respectively; OAI SD = 0.08, 0.08 and 0.11 respectively). Estimates from LME and Bayesian modelling were statistically significant predictors of change in pain in SEKOIA (LME P-value = 0.04, Bayes P-value = 0.04), while crude change did not predict change in pain (P-value = 0.10).

CONCLUSIONS

Implementation of LME or Bayesian modelling in clinical trials and epidemiological studies, would reduce sample sizes by enabling all study participants to be included in analysis regardless of incomplete follow up, and precision of change estimates would improve. They provide increased power to detect associations with other measures.

High fracture risk patients with glucocorticoid-induced osteoporosis should get an anabolic treatment first

Long-term glucocorticoid (GC) therapy induces glucocorticoid-induced osteoporosis (GIOP) and its associated fractures. Most specialty organizations recommend bisphosphonates as first-line therapies based only on bone mineral density efficacy data. Effective treatment of GIOP based on head-to-head trials with fracture endpoint has not yet been established. The pathophysiologic mechanisms of GIOP that lead to the detrimental effects on bone are not yet fully elucidated. Although GCs in an early and transitory period promote osteoclastic activity, in the current paper, we outline why GIOP is in fact a disease of the bone formation and then provide the rationale for the use of bone-forming agents as first-line therapy for patients with high fracture risk in GIOP.

Guidelines for the assessment of bone density and microarchitecture in vivo using high-resolution peripheral quantitative computed tomography

INTRODUCTION

The application of high-resolution peripheral quantitative computed tomography (HR-pQCT) to assess bone microarchitecture has grown rapidly since its introduction in 2005. As the use of HR-pQCT for clinical research continues to grow, there is an urgent need to form a consensus on imaging and analysis methodologies so that studies can be appropriately compared. In addition, with the recent introduction of the second-generation HrpQCT, which differs from the first-generation HR-pQCT in scan region, resolution, and morphological measurement techniques, there is a need for guidelines on appropriate reporting of results and considerations as the field adopts newer systems.

METHODS

A joint working group between the International Osteoporosis Foundation, American Society of Bone and Mineral Research, and European Calcified Tissue Society convened in person and by teleconference over several years to produce the guidelines and recommendations presented in this document.

RESULTS

An overview and discussion is provided for (1) standardized protocol for imaging distal radius and tibia sites using HR-pQCT, with the importance of quality control and operator training discussed; (2) standardized terminology and recommendations on reporting results; (3) factors influencing accuracy and precision error, with considerations for longitudinal and multi-center study designs; and finally (4) comparison between scanner generations and other high-resolution CT systems.

CONCLUSION

This article addresses the need for standardization of HR-pQCT imaging techniques and terminology, provides guidance on interpretation and reporting of results, and discusses unresolved issues in the field.

GNAS mutated thyroid carcinoma in a patient with Mc Cune Albright syndrome

Mc Cune-Albright syndrome (MAS) is a rare disorder defined by the triad of polyostotic fibrous dysplasia, “café au lait” skin hyperpigmentation and hyperfunctioning endocrinopathies, such as precocious puberty.

MAS is caused by an activating post zygotic somatic mutation of GNAS gene, coding for the alpha-subunit of the stimulatory G protein (Gsalpha). In endocrine tissues, this mutation results in overproduction of hormones and endocrine cell hyperfunction and proliferation.

Whereas the association of hyperthyroidism and thyroid adenomas is well known in MAS, the relation with thyroid carcinoma has rarely been observed.

We report the occurrence of a thyroid carcinoma in an 18-years old woman with MAS, revealed by subclinical hyperthyroidism detected during her systematic annual follow-up. Ultrasound and thyroid scintigraphy revealed the presence of a nodule in the right lobe. Pathology on hemithyroidectomy revealed an unexpected thyroid follicular carcinoma. Neoplastic thyroid cells harbored the GNAS R201C activating mutation. This observation suggests that MAS may predispose patients to thyroid carcinomas and supports the importance of thyroid assessment by physical examination, hormonal blood test and ultrasound, in the follow-up of patients with MAS. Because ultrasound diagnostic is challenging in MAS, needle puncture of palpable nodules should be advised.

AB0815 CHANGES IN BODY COMPOSITION, BONE MINERAL DENSITY AND BONE REMODELING MARKERS DURING INTERLEUKIN 12/23 INHIBITION IN PSORIATIC ARTHRITIS

Background:

Psoriatic arthritis (PsA) is a chronic inflammatory disease characterized by multiple comorbid conditions including cardiovascular comorbidities, diabetes, obesity and osteoporosis. Little is known about body composition in patients with PsA and no data are available regarding body composition changes under DMARDs.

Objectives:

We investigated the effects of ustekinumab (UST), a humanized anti-interleukin 12/23 antibody, on body composition, bone mineral density (BMD) and bone remodeling markers in patients treated for PsA.

Methods:

Thirty patients with active PsA treated with UST were included in a 6 months open follow-up study. Body mass index, DAS28-CRP, bone remodeling markers, serum levels of leptin, BMD and body composition (dual-energy X-ray absorptiometry) were measured at baseline and 6 months of treatment. At baseline, PsA patients were compared with 60 non-PsA controls matched for age, sex and body mass index.

Results:

Compared with controls, we observed lower total and appendicular lean mass (53.1 ±13.1 vs. 56.7 ±11.9 kg, p=0.013 and 21.6 ±6.3 vs. 23.4 ±5.0 kg, p=0.010 respectively) and greater fat mass in PsA (32.5 ±10.8 vs. 25.2 ±8.9 kg, p<0.001). Among PsA patients, 30% had a skeletal muscle mass index below the cut-off point for sarcopenia (Baumgartner’s criteria: men 7.26 kg/m2, women 5.5 kg/m2) whereas no case was observed in the control group. After 6 months of treatment with UST, there was not a significant change of BMI, while there was a tendency for reaching the significant level for fat mass (+1.75 ±3.60 kg, p=0.054), and fat mass index (+0.59 ±1.25 kg/m2, p=0.061). In contrast, a decrease in total lean mass was observed (-1.57 ±3.10 kg, p=0.046) without a significant change in appendicular lean mass and skeletal muscle mass index. No changes for bone remodeling markers, leptin and BMD were observed at 6 months.

Conclusion:

Patients with active PsA required biologic therapy had increased fat mass and decreased lean mass. Moreover, ustekinumab might worsen the decrease in lean mass with no significant change in fat mass.

Disclosure of Interests:

Julien Paccou Grant/research support from: Janssen, Speakers bureau: Abbvie, Amgen, Janssen, Lilly, MSD, Novartis, Pfizer, Sandoz, Sanofi, UCB, Wallis Bavière: None declared, Roland Chapurlat: None declared, Elisabeth Sornay-Rendu: None declared, Pawel Szulc: None declared, Bernard Cortet Consultant of: Aptissen, René-Marc Flipo Consultant of: Johnson and Johnson, MSD France, Novartis, Sanofi, Speakers bureau: Johnson and Johnson, MSD France, Novartis, Sanofi

The cartilage degradation marker, urinary CTX-II, is associated with the risk of incident total joint replacement in postmenopausal women. A 18 year evaluation of the OFELY prospective cohort

OBJECTIVE

Identifying objective risk-indicators for total joint replacement (TJR) is useful to enrich population at high risk in OA clinical trials. We investigate the association of urinary CTX-II, a biochemical marker of cartilage breakdown, with the risk of TJR.

METHOD

478 postmenopausal women (mean age 65.5 ± 7.5 yr) from the OFELY cohort were studied. CTX-II, serum CTX-I (bone resorption) and PINP (bone formation), were measured at baseline. Association between CTX-II and incidence of TJR was assessed by Cox Hazard Regression.

RESULTS

During a median (95%CI) 17.8 (15.0-18.1) years follow-up, 38 women sustained a TJR, including hip (n = 29) or knee (n = 9) replacement. CTX-II -but not CTX-I or PINP- was higher in patients with TJR (+34%, P = 0.001 vs women with no TJR). Increased baseline CTX-II levels were associated with a higher risk of TJR with a Hazard Ratio (HR) (95 CI) of 1.45 (1.13-1.85) per 1 SD increase after adjustment for age, BMI and total hip BMD. CTX-II remained significantly associated with the risk of TJR after further adjustment for total WOMAC, prevalent knee OA (KL ≥ 2) and self-reported hip OA [HR (95 CI): 1.31 (1.01-1.71), P = 0,04]. When women were categorized as low and high CTX-II (lower and above the 95 percentile of healthy premenopausal women, respectively), subjects with high levels had an age-BMI-hip BMD adjusted HR (95 CI) of 3.00 (1.54-5.85) compared to women with low levels which remained significant after further adjustment for WOMAC, knee and/or hip OA [HR (95 CI): 2.45 (1.25-4.89), P = 0.01].

CONCLUSION

CTX-II is an independent risk indicator of TJR in postmenopausal women suggesting that it may be useful to identify subjects at high risk of TJR.

Interventions to improve osteoporosis care: a systematic review and meta-analysis

Osteoporosis (OP) is a major public health concern, but still OP care does not meet guidelines. Interventions have been developed to improve appropriate OP management. The objective of the present study was to systematically review the current literature to ascertain the efficacy of interventions to improve OP care and characterize interventions taking into account elements related to their potential cost and feasibility. Studies published from 2003 to 2018 were retrieved from PubMed/MEDLINE, Science Direct, Web of Science, Cochrane, and Wiley Online Library databases. Screening of references and quality assessment were independently performed by two reviewers. We classified interventions into three types according to the target of the intervention: health system (structural interventions), healthcare professional (HCP), and patient. Meta-analysis was performed by type of intervention and their effect on two outcomes: prescription of BMD measurement and prescription of OP therapy. A total of 4268 records were screened; 32 studies were included in the qualitative analysis and 29 studies in the quantitative analysis. Structural interventions strongly and significantly improved prescription of BMD measurement (OR = 9.99, 95% CI 2.05; 48.59) and treatment prescription (OR = 3.82, 95% CI 2.16; 6.75). The impact of HCP-centered interventions on BMD measurement prescription did not reach statistical significance (OR = 2.19, 95% CI 0.84; 5.73) but significantly improved treatment prescription (OR = 3.82, 95% CI 2.16; 6.75). Interventions involving patients significantly improved the prescription of BMD measurement (OR = 2.16, 95% CI 1.62; 2.89) and treatment prescription (OR = 1.70, 95% CI 1.35; 2.14). Interventions to improve OP management had a significant positive impact on prescription of BMD measurement but a more limited impact on treatment prescription.

Serum periostin levels and severity of fibrous dysplasia of bone

Fibrous dysplasia of bone (FD) is a rare congenital bone disease, characterized by a fibrous component in the bone marrow. Periostin has been extensively researched because of its implication in various fibrotic or inflammatory diseases. Periostin may be associated with the burden or the severity of FD. The case control PERIOSDYS study aimed at assessing serum periostin levels in FD patients. Sixty four patients with monostotic or polyostotic disease were included, in order to evaluate whether the concentrations were greater in patients than in 128 healthy age, BMI and sex-matched controls and if they were more elevated in patients with the more severe phenotypes. We found that periostin levels were greater in patients with FD compared to controls (mean = 1085 vs 958 pmol/l, p = 0.026), especially in those with a history of fracture (mean = 1475 vs 966 pmol/l, p = 0.0005), polyostotic forms (mean = 1214 vs 955 pmol/l, p = 0.004) or McCune-Albright syndrome (mean = 1585 vs 1023 pmol/l, p = 0.0048). In contrast, high pain levels were not associated with periostin levels (mean = 1137 vs 1036 pmol/l, p = 0.445). Furthermore, patients undergoing bisphosphonate therapy had significantly lower levels than treatment naïve patients (mean = 953 vs 1370 pmol/l, p = 0.002). In conclusion, periostin may be a biochemical marker indicative of the most severe forms of FD and could be used to monitor patients treated with bisphosphonates.

Fibrous dysplasia of occipital bone revealed by acute intracranial hypertension

Fibrous dysplasia of bone is a stem cell bone disease due to a somatic GNAS mutation which can affect craniofacial bones. Although craniofacial fibrous dysplasia is a benign and progressive disorder, it can cause mass effect on the cranial structures. We describe an 18-year-old man, without past medical history, came at the emergency department with progressively worsening headache, associated with vomiting. Cranial bone CT and then brain MRI revealed fibrous dysplasia of occipital bone with intraosseous cyst, compression of right sigmoid vein. An angiography was performed to stent the right sigmoid vein and symptoms had completely resolved only a few hours after the procedure. Then, a treatment by bisphosphonates was introduced. We believe this is the first description of sigmoid vein compression by a bone cyst, requiring stenting. MRI should be performed urgently in case of unusual severe headache or rapidly evolving neurologic impairment in patients with craniofacial fibrous dysplasia. Treatment of fibrous dysplasia is a controversial subject. In cases with neurologic complications, surgery or endovascular treatment might be performed.

Self-perception of fracture risk: what can it tell us?

In this study, we report that self-perception of fracture risk captures some aspect of fracture risk not currently measured using conventional fracture prediction tools and is associated with improved medication uptake. It suggests that adequate appreciation of fracture risk may be beneficial and lead to greater healthcare engagement and treatment.

INTRODUCTION

This study aimed to assess how well self-perception of fracture risk, and fracture risk as estimated by the fracture prediction tool FRAX, related to fracture incidence and uptake and persistence of anti-osteoporosis medication among women participating in the Global Longitudinal study of Osteoporosis in Women (GLOW).

METHODS

GLOW is an international cohort study involving 723 physician practices across 10 countries in Europe, North America and Australia. Aged ≥ 55 years, 60,393 women completed baseline questionnaires detailing medical history, including co-morbidities, fractures and self-perceived fracture risk (SPR). Annual follow-up included self-reported incident fractures and anti-osteoporosis medication (AOM) use. We calculated FRAX risk without bone mineral density measurement.

RESULTS

Of the 39,241 women with at least 1 year of follow-up data, 2132 (5.4%) sustained an incident major osteoporotic fracture over 5 years of follow-up. Within each SPR category, risk of fracture increased as the FRAX categorisation of risk increased. In GLOW, only 11% of women with a lower baseline SPR were taking AOM at baseline, compared with 46% of women with a higher SPR. AOM use tended to increase in the years after a reported fracture. However, women with a lower SPR who were fractured still reported lower AOM rates than women with or without a fracture but had a higher SPR.

CONCLUSIONS

These results suggest that SPR captures some aspect of fracture risk not currently measured using conventional fracture prediction tools and is also associated with improved medication uptake.

Improving patient outcomes in fibrous dysplasia/McCune-Albright syndrome: an international multidisciplinary workshop to inform an international partnership

To develop consensus on improving the management of patients, we convened an international workshop involving patients, clinicians, and researchers. Key findings included the diagnostic delay and variability in subsequent management with agreement to develop an international natural history study. We now invite other stakeholders to join the partnership.

PURPOSE

The aim of this study was develop a consensus on how to improve the management of patients with fibrous dysplasia and prioritize areas for research METHODS: An international workshop was held over 3 days involving patients, clinicians, and researchers. Each day had a combination of formal presentations and facilitated discussions that focused on clinical pathways and research.

RESULTS

The patient workshop day highlighted the variability of patients' experience in getting a diagnosis, the knowledge of general clinical staff, and understanding long-term outcomes. The research workshop prioritized collaborations that improved understanding of the contemporary natural history of fibrous dysplasia/McCune-Albright syndrome (FD/MAS). The clinical workshop outlined the key issues around diagnostics, assessment of severity, treatment and monitoring of patients.

CONCLUSIONS

In spite of advances in understanding the genetic and molecular underpinnings of fibrous dysplasia/McCune-Albright syndrome, clinical management remains a challenge. From the workshop, a consensus was reached to create an international, multi-stakeholder partnership to advance research and clinical care in FD/MAS. We invite other stakeholders to join the partnership.

Children and adolescents with cystic fibrosis display moderate bone microarchitecture abnormalities: data from high-resolution peripheral quantitative computed tomography

We investigated whether bone microstructure assessed by high-resolution peripheral quantitative tomography (HR-pQCT) could be altered in children and teenagers with cystic fibrosis (CF). In comparison to their healthy counterparts, bone microstructure was mildly affected at the tibial level only.

INTRODUCTION

Cystic fibrosis-related bone disease (CFBD) may alter bone health, ultimately predisposing patients to bone fractures. Our aim was to assess bone microstructure using high-resolution peripheral quantitative tomography (HR-pQCT) in a cohort of children and teenagers with CF in comparison to age-, puberty-, and gender-matched healthy volunteers (HVs).

METHODS

In this single-center, prospective, cross-sectional study, we evaluated the HR-pQCT bone parameters of CF patients and compared them to those of the healthy volunteers.

RESULTS

At a median age of 15.4 [range, 10.5-17.9] years, 37 CF patients (21 boys) with 91% [range, 46-138%] median forced expiratory volume in 1 s were included. At the ultradistal tibia, CF patients had a smaller bone cross-sectional area (579 [range, 399-1087] mm²) than HVs (655 [range, 445-981] mm²) (p = 0.027), related to a decreased trabecular area, without any significant differences for height. No other differences were found (trabecular number, separation, thickness, or distribution) at the radial or tibial levels. Bone structure was different in patients receiving ursodeoxycholic acid and those bearing two F508del mutations.

CONCLUSION

In our cohort of children and teenagers with good nutritional and lung function status, bone microstructure evaluated with HR-pQCT was not severely affected. Minimal microstructure abnormalities observed at the tibial level may be related to the cystic fibrosis transmembrane conductance regulator defect alone; the long-term consequences of such impairment will require further evaluation.

Effect of denosumab on trabecular bone score in postmenopausal women with osteoporosis

Trabecular bone score (TBS) assesses bone quality in the lumbar spine using dual-energy X-ray absorptiometry (DXA) scans. In postmenopausal women with osteoporosis, denosumab significantly improved TBS independently of bone mineral density (BMD). This practical technique may have a role in managing patients with osteoporosis.

INTRODUCTION

TBS, a gray-level texture index determined from lumbar spine DXA scans, correlates with bone microarchitecture and enhances assessment of vertebral fracture risk independently of BMD. In the FREEDOM study, denosumab increased BMD and reduced new vertebral fractures in postmenopausal women with osteoporosis. This retrospective analysis explored the effect of denosumab on TBS and the association between TBS and BMD in FREEDOM.

METHODS

Postmenopausal women with lumbar spine or total hip BMD T-score <-2.5 and -4.0 or higher at both sites received placebo or denosumab 60 mg subcutaneously every 6 months. TBS indices were determined from DXA scans at baseline and months 12, 24, and 36 in a subset of 285 women (128 placebo, 157 denosumab) who had TBS values at baseline and ≥1 postbaseline visit.

RESULTS

Baseline characteristics were comparable between treatment groups; mean (SD) lumbar spine BMD T-score was -2.79 (0.64), and mean (standard deviation [SD]) TBS was 1.200 (0.101) overall. In the placebo group, BMD and TBS increased by ≤0.2% or decreased from baseline at each visit. In the denosumab group, progressive increases from baseline at 12, 24, and 36 months were observed for BMD (5.7, 7.8, and 9.8%) and TBS (1.4, 1.9, and 2.4%). Percentage changes in TBS were statistically significant compared with baseline (p < 0.001) and placebo (p ≤ 0.014). TBS was largely unrelated to BMD, regardless of treatment, either at baseline or for annual changes from baseline (all r ² ≤ 0.06).

CONCLUSIONS

In postmenopausal women with osteoporosis, denosumab significantly improved TBS independently of BMD.

Nutrition and physical activity in the prevention and treatment of sarcopenia: systematic review

This systematic review summarizes the effect of combined exercise and nutrition intervention on muscle mass and muscle function. A total of 37 RCTs were identified. Results indicate that physical exercise has a positive impact on muscle mass and muscle function in subjects aged 65 years and older. However, any interactive effect of dietary supplementation appears to be limited.

INTRODUCTION

In 2013, Denison et al. conducted a systematic review including 17 randomized controlled trials (RCTs) to explore the effect of combined exercise and nutrition intervention to improve muscle mass, muscle strength, or physical performance in older people. They concluded that further studies were needed to provide evidence upon which public health and clinical recommendations could be based. The purpose of the present work was to update the prior systematic review and include studies published up to October 2015.

METHODS

Using the electronic databases MEDLINE and EMBASE, we identified RCTs which assessed the combined effect of exercise training and nutritional supplementation on muscle strength, muscle mass, or physical performance in subjects aged 60 years and over. Study selection and data extraction were performed by two independent reviewers.

RESULTS

The search strategy identified 21 additional RCTs giving a total of 37 RCTs. Studies were heterogeneous in terms of protocols for physical exercise and dietary supplementation (proteins, essential amino acids, creatine, β-hydroxy-β-methylbuthyrate, vitamin D, multi-nutrients, or other). In 79% of the studies (27/34 RCTs), muscle mass increased with exercise but an additional effect of nutrition was only found in 8 RCTs (23.5%). Muscle strength increased in 82.8% of the studies (29/35 RCTs) following exercise intervention, and dietary supplementation showed additional benefits in only a small number of studies (8/35 RCTS, 22.8%). Finally, the majority of studies showed an increase of physical performance following exercise intervention (26/28 RCTs, 92.8%) but interaction with nutrition supplementation was only found in 14.3% of these studies (4/28 RCTs).

CONCLUSION

Physical exercise has a positive impact on muscle mass and muscle function in healthy subjects aged 60 years and older. The biggest effect of exercise intervention, of any type, has been seen on physical performance (gait speed, chair rising test, balance, SPPB test, etc.). We observed huge variations in regard to the dietary supplementation protocols. Based on the included studies, mainly performed on well-nourished subjects, the interactive effect of dietary supplementation on muscle function appears limited.

Post-fracture care: do we need to educate patients rather than doctors? The PREVOST randomized controlled trial

We conducted a multicenter, randomized controlled trial to evaluate the impact of a population-based patient-centered post-fracture care program with a dedicated case manager, PREVention of OSTeoporosis (PREVOST), on appropriate post-fracture osteoporosis management. We showed that, compared to usual care, BMD investigation post-fracture was significantly improved (+20%) by our intervention program.

INTRODUCTION

Our study aims to evaluate the impact of a population-based patient-centered post-fracture care program, PREVOST, on appropriate post-fracture care.

METHODS

Multicenter, randomized controlled trial enrolling 436 women aged 50 to 85 years and attending a French hospital, for a low-energy fracture of the wrist or humerus. Randomization was stratified by age, hospital department, and site of fracture. The intervention was performed by a trained case manager who interacted only with the patients, with repeated oral and written information about fragility fractures and osteoporosis management, and prompting them to visit their primary care physicians. Control group received usual care. The primary outcome was the initiation of an appropriate post-fracture care defined by Bone Mineral Density (BMD) and/or anti-osteoporotic treatment prescription at 6 months.

RESULTS

At 6 months, 53% of women in intervention group initiated a post-fracture care versus 33% for usual care (adjOR 2.35, 95%CI [1.58-3.50], p < 0.001). Post-fracture care was more frequent after wrist than humerus fracture (adjOR 1.93, 95%CI [1.14-3.30], p = 0.015) and decreased with age (adjOR for 10 years increase 0.76, 95%CI [0.61-0.96], p = 0.02). The intervention resulted in BMD prescription in 50% of patients (adjOR 2.10, 95%CI [1.41-3.11], p < 0.001) and in BMD performance in 41% of patients (adjOR 2.12, 95%CI [1.40-3.20], p < 0.001) versus 33 and 25% for usual care, respectively. Having performed a BMD increased treatment prescription; however, only 46% of women with a low BMD requiring a treatment according to the French guidelines received a prescription.

CONCLUSION

A patient-centered care program with a dedicated case manager can significantly improve post-fracture BMD investigation.

Operator variability in scan positioning is a major component of HR-pQCT precision error and is reduced by standardized training

In this study, we determined that operator positioning precision contributes significant measurement error in high-resolution peripheral quantitative computed tomography (HR-pQCT). Moreover, we developed software to quantify intra- and inter-operator variability and demonstrated that standard positioning training (now available as a web-based application) can significantly reduce inter-operator variability.

INTRODUCTION

HR-pQCT is increasingly used to assess bone quality, fracture risk, and anti-fracture interventions. The contribution of the operator has not been adequately accounted in measurement precision. Operators acquire a 2D projection ("scout view image") and define the region to be scanned by positioning a "reference line" on a standard anatomical landmark. In this study, we (i) evaluated the contribution of positioning variability to in vivo measurement precision, (ii) measured intra- and inter-operator positioning variability, and (iii) tested if custom training software led to superior reproducibility in new operators compared to experienced operators.

METHODS

To evaluate the operator in vivo measurement precision, we compared precision errors calculated in 64 co-registered and non-co-registered scan-rescan images. To quantify operator variability, we developed software that simulates the positioning process of the scanner's software. Eight experienced operators positioned reference lines on scout view images designed to test intra- and inter-operator reproducibility. Finally, we developed modules for training and evaluation of reference line positioning. We enrolled six new operators to participate in a common training, followed by the same reproducibility experiments performed by the experienced group.

RESULTS

In vivo precision errors were up to threefold greater (Tt.BMD and Ct.Th) when variability in scan positioning was included. The inter-operator precision errors were significantly greater than the short-term intra-operator precision (p < 0.001). New trained operators achieved comparable intra-operator reproducibility to experienced operators and lower inter-operator reproducibility (p < 0.001). Precision errors were significantly greater for the radius than for the tibia.

CONCLUSION

Operator reference line positioning contributes significantly to in vivo measurement precision and is significantly greater for multi-operator datasets. Inter-operator variability can be significantly reduced using a systematic training platform, now available online ( http://webapps.radiology.ucsf.edu/refline/ ).

Clinical cone beam computed tomography compared to high-resolution peripheral computed tomography in the assessment of distal radius bone

Clinical cone beam computed tomography (CBCT) was compared to high-resolution peripheral quantitative computed tomography (HR-pQCT) for the assessment of ex vivo radii. Strong correlations were found for geometry, volumetric density, and trabecular structure. Using CBCT, bone architecture assessment was feasible but compared to HR-pQCT, trabecular parameters were overestimated whereas cortical ones were underestimated.

INTRODUCTION

HR-pQCT is the most widely used technique to assess bone microarchitecture in vivo. Yet, this technology has been only applicable at peripheral sites, in only few research centers. Clinical CBCT is more widely available but quantitative assessment of the bone structure is usually not performed. We aimed to compare the assessment of bone structure with CBCT (NewTom 5G, QR, Verona, Italy) and HR-pQCT (XtremeCT, Scanco Medical AG, Brüttisellen, Switzerland).

METHODS

Twenty-four distal radius specimens were scanned with these two devices with a reconstructed voxel size of 75 μm for Newtom 5G and 82 μm for XtremeCT, respectively. A rescaling-registration scheme was used to define the common volume of interest. Cortical and trabecular compartments were separated using a semiautomated double contouring method. Density and microstructure were assessed with the HR-pQCT software on both modality images.

RESULTS

Strong correlations were found for geometry parameters (r = 0.98-0.99), volumetric density (r = 0.91-0.99), and trabecular structure (r = 0.94-0.99), all p < 0.001. Correlations were lower for cortical microstructure (r = 0.80-0.89), p < 0.001. However, absolute differences were observed between modalities for all parameters, with an overestimation of the trabecular structure (trabecular number, 1.62 ± 0.37 vs. 1.47 ± 0.36 mm(-1)) and an underestimation of the cortical microstructure (cortical porosity, 3.3 ± 1.3 vs. 4.4 ± 1.4 %) assessed on CBCT images compared to HR-pQCT images.

CONCLUSIONS

Clinical CBCT devices are able to analyze large portions of distal bones with good spatial resolution and limited irradiation. However, compared to dedicated HR-pQCT, the assessment of microarchitecture by NewTom 5G dental CBCT showed some discrepancies, for density measurements mainly. Further technical developments are required to reach optimal assessment of bone characteristics.

Reduced bone volumetric density and weak correlation between infection and bone markers in cystic fibrosis adult patients

In our current adult CF population, low BMD prevalence was only 20 %, lower than that historically described. We found a mild increase of serum RANK-L levels, independent from the bone resorption level. The increased fracture risk in CF may be explained by a lower tibial cortical thickness and total vBMD.

INTRODUCTION

Bone disease is now well described in cystic fibrosis (CF) adult patients. CF bone disease is multifactorial but many studies suggested the crucial role of inflammation. The objectives of this study were, in a current adult CF population, to assess the prevalence of bone disease, to examine its relationship with infections and inflammation, and to characterize the bone microarchitecture using high resolution peripheral scanner (HR-pQCT).

METHODS

Fifty-six patients (52 % men, 26 ± 7 years) were assessed in clinically stable period, during a respiratory infection, and finally 14 days after the end of antibiotic therapy. At each time points, we performed a clinical evaluation, lung function tests, and biochemical tests. Absorptiometry and dorso-lumbar radiographs were also performed. A subgroup of 40 CF patients (63 % men, 29 ± 6 years) underwent bone microarchitecture assessment and was age- and gender-matched with 80 healthy controls.

RESULTS

Among the 56 CF patients, the prevalence of low areal BMD (T-score < -2 at any site), was 20 % (95 % CI: [10.2 %; 32.4 %]). After infections, serum RANK-L (+24 %, p = 0.08) and OPG (+13 %, p = 0.04) were increased with a stable ratio. Microarchitectural differences were mostly observed at the distal tibia, with lower total and cortical vBMD and trabecular thickness (respectively -9.9, -3.0, and -5 %, p < 0.05) in CF patients compared to controls, after adjustment for age, gender, weight, and height.

CONCLUSIONS

In this study, bone disease among adult CF patients was less severe than that previously described with only 20 % of CF patients with low BMD. We found a mild increase of biological marker levels and an impaired volumetric density of the tibia that may explain the increased fracture risk in CF population.

Vertebral body morphology is associated with incident lumbar vertebral fracture in postmenopausal women. The OFELY study

We investigate the predictive role of vertebral anterior cortical curvature and height heterogeneity in the occurrence of vertebral fractures in postmenopausal women. Women who will fracture had shorter vertebral height, greater heterogeneity of height than those who will not fracture, and their anterior vertebral body edge was less concave.

INTRODUCTION

Vertebral morphology has been demonstrated to be associated with further risk of fracture. The aim of this study was to analyze vertebral anterior cortical curvature (Ct.curv) and vertebral height heterogeneity in postmenopausal women before the occurrence of a vertebral fracture.

METHODS

This case-control study included 29 postmenopausal women who have underwent incident lumbar vertebral fractures (mean age 71 ± 9 years, mean time to fractures 9 ± 4 years), age-matched with 57 controls. From lateral X-rays of lumbar spine radiographs (T12 to L4), the following parameters were measured: (1) the posterior, middle, and anterior vertebral heights; (2) the heterogeneity of heights evaluated by the coefficient of variation of these three variables; (3) antero-posterior width, a 2D estimator of cross-sectional area; and (4) Ct.curv.

RESULTS

Mean vertebral heights were significantly lower among women who fractured than in controls (p < 0.05). The anterior and middle heights were significantly lower at L4 and L3 levels in fracture group (p = 0.02). The heterogeneity of vertebral height was significantly greater in the fracture group (p = 0.003). In addition, fractured patients had a significantly higher Ct.curv on L3 (p = 0.04). After adjustment for bone mineral density (BMD), only the heterogeneity of vertebral height remained significant (p = 0.005).

CONCLUSION

The current case-control study confirmed the association between vertebral height and occurrence of future vertebral fracture in postmenopausal women. The vertebrae with the smallest Ct.curv tended to fracture less often, and the heterogeneity of vertebral heights was associated with future fracture independently of BMD. An additional validation in a prospective study would be needed to confirm these initial results.

Oxytocin and bone status in men: analysis of the MINOS cohort

Oxytocin, a neurohypophysial hormone, regulates bone metabolism in animal studies and postmenopausal women. In men, oxytocin is not associated with bone mineral density, bone turnover markers, or prevalent fractures, but weakly negatively with incident fragility fracture requiring further studies.

INTRODUCTION

We previously showed that serum oxytocin (OT) level is associated with bone mineral density (BMD) and bone turnover rate in postmenopausal women. The aim of our study was to assess the relationship between circulating OT levels and bone status in men.

METHODS

In 552 men aged 50 and older from the MINOS cohort, we measured serum levels of OT. We assessed the association of serum OT levels with BMD (lumbar, femoral neck, total hip), bone turnover markers (BTM) (serum N-terminal propeptide of type I procollagen (PINP), bone-specific alkaline phosphatase (bone ALP), and C-terminal telopeptide of type I collagen (CTX-I)) and fracture risk.

RESULTS

In the univariate analysis, serum OT level was not associated with BMD at any site, BTM levels, or with prevalent or incident fracture. OT was significantly correlated with body mass index (BMI) (r = 0.17, p < 0.001), total or bioavalaible 17β-estradiol (r = 0.09, p = 0.04 and r = 0.20, p < 0.001, respectively), free testosterone (r = 0.17, p < 0.001), and leptin (r = 0.16, p < 0.001). Multivariate analysis did not show significant relationship between serum OT and BMD. After adjustment for age, BMI, interaction BMI/age, history of fall in the last year, and BMD, OT and prevalent fracture were not associated. By contrast, the same analysis with additional adjustment for prevalent fracture showed a weakly significant negative association between OT and incident fracture, e.g., after adjustment for femoral neck BMD, HR = 0.73, 95 %CI 0.55-0.99, p = 0.04.

CONCLUSION

In men, serum OT levels are not associated with BMD, bone turnover rate, or prevalent fractures. The weak negative relationship with fracture risk requires further studies.

Taxonomy of rare genetic metabolic bone disorders

This article reports a taxonomic classification of rare skeletal diseases based on metabolic phenotypes. It was prepared by The Skeletal Rare Diseases Working Group of the International Osteoporosis Foundation (IOF) and includes 116 OMIM phenotypes with 86 affected genes.

INTRODUCTION

Rare skeletal metabolic diseases comprise a group of diseases commonly associated with severe clinical consequences. In recent years, the description of the clinical phenotypes and radiographic features of several genetic bone disorders was paralleled by the discovery of key molecular pathways involved in the regulation of bone and mineral metabolism. Including this information in the description and classification of rare skeletal diseases may improve the recognition and management of affected patients.

METHODS

IOF recognized this need and formed a Skeletal Rare Diseases Working Group (SRD-WG) of basic and clinical scientists who developed a taxonomy of rare skeletal diseases based on their metabolic pathogenesis.

RESULTS

This taxonomy of rare genetic metabolic bone disorders (RGMBDs) comprises 116 OMIM phenotypes, with 86 affected genes related to bone and mineral homeostasis. The diseases were divided into four major groups, namely, disorders due to altered osteoclast, osteoblast, or osteocyte activity; disorders due to altered bone matrix proteins; disorders due to altered bone microenvironmental regulators; and disorders due to deranged calciotropic hormonal activity.

CONCLUSIONS

This article provides the first comprehensive taxonomy of rare metabolic skeletal diseases based on deranged metabolic activity. This classification will help in the development of common and shared diagnostic and therapeutic pathways for these patients and also in the creation of international registries of rare skeletal diseases, the first step for the development of genetic tests based on next generation sequencing and for performing large intervention trials to assess efficacy of orphan drugs.

Serum periostin is associated with prevalent knee osteoarthritis and disease incidence/progression in women: the OFELY study

OBJECTIVE

Our aim was to investigate the relationships between serum periostin (POSTN) and both prevalence and incidence/progression of knee osteoarthritis (OA) in women.

METHODS

We investigated 594 women (62.7 ± 11.2 yr) from the OFELY cohort. Knee radiographs were scored according to the Kellgren & Lawrence (KL) grading system at baseline and 4 years later. Spine, hip and hand OA were assessed at baseline. Prevalent knee OA was defined by a KL score higher or equal in 2. Progression of KL was defined as an increase of the KL score ≥1 during the 4 years follow-up. Serum POSTN was measured at baseline by ELISA.

RESULTS

By non-parametric tests, POSTN was significantly lower in 83 women with a KL score ≥2 at baseline, compared to those with a KL score <2 (n = 511; 1101 ± 300 vs 1181 ± 294 ng/ml, P = 0.002) after adjustment for age, body mass index (BMI), treatments and diseases, prevalent hand OA and prevalent lumbar spine OA. By logistic regression analyses, the odds-ratio of knee OA incidence/progression was significantly reduced by 21% (P = 0.043) for each quartile increase in serum POSTN at baseline, after adjustment for age, BMI, prevalent knee OA, prevalent hand OA and prevalent lumbar spine OA.

CONCLUSIONS

We show for the first time that serum POSTN is associated with prevalence and the risk of development/progression of knee OA in women.

Serum sclerostin: the missing link in the bone-vessel cross-talk in hemodialysis patients?

We found for the first time that in maintenance hemodialysis patients, higher sclerostin serum level was associated with severe abdominal aortic calcification (AAC). In addition, cortical bone microarchitecture (density and thickness) assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT) at tibia was also independently associated with severe AAC. These results suggest that sclerostin may be involved in the association of mineral and bone disorder with vascular calcification in hemodialysis patients.

INTRODUCTION

Severe abdominal aortic calcifications are predictive of high cardiovascular mortality in maintenance hemodialysis (MHD) patients. In patients with end-stage renal disease, a high aortic calcification score was associated with lower bone turnover on bone biopsies. Thus, we hypothesized that sclerostin, a Wnt pathway inhibitor mainly secreted by osteocytes and acting on osteoblasts to reduce bone formation, may be associated with vascular calcifications in MHD patients.

METHODS

Fifty-three MHD patients, aged 53 years [35-63] (median [Q1-Q3]) were included. Serum was sampled before the MHD session to assay sclerostin. Framingham score was computed and the abdominal aortic calcification (AAC) score was assessed according to Kauppila method on lateral spine imaging using DEXA. Tibia bone status was evaluated by high-resolution peripheral quantitative computed tomography (HR-pQCT). Patients were distributed into two groups according to their AAC score: patients with mild or without AAC (score below 6) versus patients with severe AAC (score of 6 and above).

RESULTS

In multivariate analysis, after adjustment on age, dialysis duration and diabetes, serum sclerostin and cortical thickness were independently associated with severe AAC (odds ratio (OR) = 1.43 for each 0.1 ng/mL increase [95 % confidence interval (CI) 1.10-1.83]; p = 0.006 and 0.16 for 1 SD increase [0.03-0.73]; p = 0.018, respectively). A second cardiovascular model adjusted on Framingham score and the above mentioned confounders showed similar results.

CONCLUSIONS

Elevated sclerostin serum level and poorer tibia cortical bone structure by HR-pQCT were positively and independently associated with higher odds of severe AAC in MHD patients. Serum sclerostin may become a biomarker of mineral and bone disorder and vascular risk in MHD patients.

Family resemblance of bone turnover rate in mothers and daughters--the MODAM study

We studied bone turnover markers (BTM) and bone microarchitecture (using high-resolution peripheral quantitative computed tomography (HR-pQCT)) in 171 postmenopausal women and their 210 premenopausal daughters. BTM levels correlated positively between mothers and daughters. The mother-daughter pairs with high BTM levels had lower cortical density than those with low BTM levels.

INTRODUCTION

We assessed the correlation of serum bone turnover markers (BTM) between postmenopausal mothers and their premenopausal daughters as well as possible determinants of this association and its impact on resemblance of bone microarchitecture between mothers and their daughters.

METHODS

Cross-sectional analysis was performed in 171 untreated postmenopausal mothers (54 sustained fragility fractures) and their 210 premenopausal daughters. Intact N-terminal propeptide of type I collagen (PINP) and β-isomerized C-terminal crosslinking telopeptide of type I collagen (CTX-I) were measured in the fasting status. Bone microarchitecture was assessed using HR-pQCT.

RESULTS

After adjustment for age, weight, lifestyle factors, hormones, and mother's fracture status, BTM levels correlated positively between mothers and daughters (Intraclass Correlation Coefficient = 0.22-0.27, p <0.005). Average BTM levels were ∼ 0.6 SD higher among daughters of mothers in the highest BTM quartile vs. the ones in the lowest BTM quartile. The variability of BTM levels explained ≤ 10 and ≤ 14% of variability of bone microarchitecture in the daughters and mothers, respectively. Cortical density was lower by 2.3-2.9% (0.6 SD, p <0.05 to <0.005) in the daughters from the mother-daughter pairs with high BTM levels (defined by generation-specific quartiles) than in the daughters from the pairs with low BTM levels. Corresponding differences for the mothers were 4.5-4.8% (0.5 SD, p <0.05 to <0.01).

CONCLUSION

BTM levels correlated between postmenopausal mothers and their premenopausal daughters after adjustment for age, weight, mother's fracture status, lifestyle, and hormonal factors. Family resemblance of BTM levels may contribute to family resemblance of some bone microarchitectural parameters, especially of cortical density.