Bisphosphonate therapy for osteoporosis: benefits, risks, and drug holiday

Clinical Management of Osteoporotic Fractures

PURPOSE OF REVIEW

This review examines recent literature regarding the clinical management of fragility fractures, provides insight into new practice patterns, and discusses controversies in current management.

RECENT FINDINGS

There are declining rates of osteoporosis management following initial fragility fracture. Management of osteoporotic fractures via a multidisciplinary team reduces secondary fracture incidence and improves overall osteoporotic care. Anabolic agents (abaloparatide and teriparatide) are effective adjuvants to fracture repair, and have shown positive results in cases of re-fracture in spite of medical management (i.e., bisphosphonates). For AO 31-A1 and A2 intertrochanteric hip fractures (non-reverse obliquity), no clinical advantage of intramedullary fixation over the sliding hip screw (SHS) has been proven; SHS is more cost-effective. As fragility fracture incidence continues to rise, orthopedic surgeons must play a more central role in the care of osteoporotic patients. Initiation of pharmacologic intervention is key to preventing subsequent fragility fractures, and may play a supportive role in initial fracture healing. While the media bombards patients with complications of medical therapy (atypical femur fractures, osteonecrosis of jaw, myocardial infarction), providers need to understand and communicate the low incidence of these complications compared with consequences of not initiating medical therapy.

Effects of discontinuing oral bisphosphonate treatments for postmenopausal osteoporosis on bone turnover markers and bone density

The antiresorptive potency varies between different bisphosphonates. We investigated the effect of stopping oral bisphosphonate treatment for postmenopausal osteoporosis (ibandronate, alendronate, risedronate) on BTMs and BMD. After stopping treatment, all three groups showed an increase in BTMs and a decrease in hip BMD; however, none returned to pre-treatment baseline values.

INTRODUCTION

Bisphosphonates (BPs) continue to suppress bone turnover markers (BTMs) after treatment has stopped, leading to the suggestion that a pause in treatment could be considered for low-risk patients. Indirect comparisons suggest that after cessation of treatment, the effects on bone may differ between drugs. We investigated the effects of stopping oral BP treatments for postmenopausal osteoporosis on BTMs and bone mineral density (BMD).

METHODS

We studied postmenopausal osteoporotic women who had previously taken part in a 2-year randomised study of three oral BPs (ibandronate, alendronate, or risedronate). At the end of the study, women with hip BMD T-score > - 2.5 and considered clinically appropriate to discontinue treatment were invited to participate in a further 2-year observational study. Biochemical response was assessed using BTMs, and BMD was measured by dual-energy X-ray absorptiometry.

RESULTS

All BTMs increased after treatment withdrawal but remained below the pre-treatment baseline with less suppression of BTMs for the risedronate group compared to alendronate and ibandronate up to 48 weeks. There was no difference between the BP groups 96 weeks after stopping treatment. The change in BMD during the 96 weeks after stopping treatment was - 1.6% (95% CI - 1.9 to - 1.2, P < 0.001) for the total hip and - 0.6% (95% CI - 1.1 to - 0.2, P = 0.17) at the lumbar spine with no difference between the three BP groups (P = 0.85 and P = 0.48, respectively).

CONCLUSION

For all treatment groups, there was an increase in BTMs and a decrease in hip BMD after stopping BPs for 2 years; however, none returned to pre-treatment baseline values.

Long-term benefits and risks of parathyroid hormone treatment in compliant osteoporotic patients. A Danish national register based cohort study

PURPOSE

Medical treatment of osteoporosis should preferably be both effective and have minimal side effects. The aim of the present study was to examine long-term benefits and risks of parathyroid hormone (PTH) treatment in compliant patients.

METHODS

This is a nationwide retrospective cohort study based on national registers in which we identified 1739 patients treated with PTH (2003-2010) (index cases) for at least 18 months and with a medication possession rate of > 0.8. For comparison, patients treated with bisphosphonate (BP) (n = 13,131) and anti-osteoporotic treatment-naïve controls (n = 12,721) were selected. Incidence of fractures, drug consumption, and comorbidity were compared between the three cohorts. Mean follow-up of the PTH-treated patients was 4.3 years (range 1.8-8.7 years).

RESULTS

Before initiation of treatment, PTH patients had a significantly higher Charlson comorbidity index score and more osteoporotic fractures than both BP patients and controls. No difference was detected in the incidence of fractures during PTH treatment or years after between PTH patients and BP patients. No significant difference in the use of drugs was seen between PTH and BP patients, except for PPI intake which was higher in PTH patients. No significant increases were found in the incidence of cancers or other ICD-10 diagnoses among PTH-treated patients in comparison with both BP and controls.

CONCLUSION

Overall, PTH treatment is effective and safe. Following PTH treatment in compliant patients, neither fracture incidence nor drug consumption differed between PTH-treated and BP-treated patients, despite the fact that PTH-treated patients had more severe osteoporosis. No increased incidence of malignant diseases or other diseases was detected.

Trends and Determinants of Osteoporosis Treatment and Screening in Patients With Rheumatoid Arthritis Compared to Osteoarthritis

OBJECTIVE

To profile osteoporosis (OP) care in patients with rheumatoid arthritis (RA) over the past decade.

METHODS

Patients with RA or osteoarthritis (OA) were followed from 2003 through 2014. OP care was defined as receipt of OP treatment (with the exception of calcium/vitamin D) or screening (OPTS). Adjusted trends over followup, and the factors associated with OP care, were examined using multivariable Cox proportional hazards.

RESULTS

OPTS was reported in 67.4% of 11,669 RA patients and in 64.6% of 2,829 OA patients during a median (interquartile range) 5.5 (2-9) years of followup. In patients for whom treatment was recommended by the 2010 American College of Rheumatology (ACR) glucocorticoid-induced OP (GIOP) guidelines (48.4% of RA patients and 17.6% of OA patients), approximately 55% overall reported OP medication use. RA patients were not more likely to undergo OPTS compared to OA patients (hazard ratio 1.04 [95% confidence interval 0.94-1.15]). Adjusted models showed a stable trend for OPTS between 2004 and 2008 compared to 2003, with a significant downward trend after 2008 in both RA and OA patients. Factors associated with receipt of OP care in RA patients were older age, postmenopausal state, prior fragility fracture or diagnosis of OP, any duration of glucocorticoid treatment, and use of biologic agents.

CONCLUSION

Approximately half of RA patients for whom treatment was indicated never received an OP medication. OP care in RA patients was not better than in OA patients, and the relative risk of the application of this care has been decreasing in RA and OA patients since 2008 without improvement after the release of the 2010 ACR GIOP guideline.

Using a sequential explanatory mixed method to evaluate the therapeutic window of opportunity for initiating osteoporosis treatment following fragility fractures

Interventions targeting patients with recent fragility fracture and their physician were most successful at initiating osteoporosis treatment during the first 12 months. This window of opportunity had already closed after 1 year. The reasons for declining or accepting the intensive intervention were explored in patients still untreated at 12 months.

INTRODUCTION

A fragility fracture (FF) event identifies patients most likely to benefit from osteoporosis treatment. Nonetheless, most FF patients go untreated. Our objective was to determine how long an incident FF remains a strong incentive to initiate osteoporosis treatment.

METHODS

A total of 1086 men and women over age 50 with a recent FF event were assigned to either standard care (SC), to minimal (MIN), or intensive (INT) interventions targeting patients and their family physician to initiate osteoporosis treatment. Inpatients with FF (mainly hip) evaluated by rheumatologists were also included in a specialized group (SPE; n = 324). At 1 year, untreated patients in both the SC and the MIN groups were offered an INT intervention. The cohort was followed through 48 months. A qualitative analysis of patient-centered decision-making associated with initiation of treatment was conducted.

RESULTS

In MIN and INT groups, osteoporosis treatment was initiated in 41.0 and 54.3% of untreated patients by 12 months, respectively, compared to 68.4% in SPE and 18.9% in SC groups; initiation rates drastically dropped thereafter. Over 4863 patient-years of follow-up, the rates of new FF were 3.4 per 100 patient-years, without significant differences between patients with initial major or minor FF, nor between control or intervention groups. Failure by patients and physicians to recognize FF as a sign of underlying bone disease contributed the most to lack of treatment.

CONCLUSION

While incident FFs are an ideal opportunity for starting osteoporosis treatment, 1 year later, the therapeutic window of opportunity has already closed.

Effects of denosumab on bone metabolism and bone mineral density with anti-TNF inhibitors, tocilizumab, or abatacept in osteoporosis with rheumatoid arthritis

Introduction

The aim of this 18-month retrospective study was to evaluate the differences in outcomes of denosumab with tumor necrosis factor (TNF) inhibitors (TNFis), tocilizumab (TCZ), or abatacept (ABT) treatment in osteoporosis (OP) patients with rheumatoid arthritis (RA).

Patients and methods

Patients were divided into TNFis-treated (TNF group; 44 cases), TCZ-treated (TCZ group; 8 cases), or ABT-treated (ABT group; 14 cases) groups. We measured serum bone-specific alkaline phosphatase (BAP) and tartrate-resistant acid phosphatase 5b (TRACP-5b) at baseline and every 3 months for 18 months and assessed bone mineral density (BMD) of the lumbar 1–4 vertebrae (L-BMD) and total hip BMD (H-BMD) at baseline and every 6 months for 18 months.

Results

There were no significant differences in the percent changes in BAP, TRACP-5b, or L-BMD among the groups. The percent change in H-BMD was significantly increased in the TCZ group at 12 months or at 12 and 18 months, compared with that in the ABT group or TNF group, respectively. The percent change in L-BMD was significantly increased at 12 months in the TCZ and TNF groups, and at 18 months in all the 3 groups compared with pretreatment levels, whereas the percent change in H-BMD was significantly higher at 6, 12, and 18 months in the TCZ group, at 12 and 18 months in the TNF group, and at 18 months in the ABT group, compared with pretreatment levels.

Conclusion

Our findings suggest that TCZ might be more useful than TNF or ABT in light of the observed H-BMD increases with denosumab therapy for OP patients with RA.

Insights into the bisphosphonate holiday: a preliminary FTIRI study

Bone composition evaluated by FTIRI analysis of iliac crest biopsies from post-menopausal women treated with alendronate for 10 years, continuously or alendronate for 5 years, followed by a 5-year alendronate-holiday, only differed with the discontinued biopsies having increased cortical crystallinity and heterogeneity of acid phosphate substitution and decreased trabecular crystallinity heterogeneity.

INTRODUCTION

Bisphosphonates (BP) are the most commonly used and effective drugs to prevent fragility fractures; however, concerns exist that prolonged use may lead to adverse events. Recent recommendations suggest consideration of a BP "holiday" in individuals taking long-term BP therapy not at high risk of fracture. Data supporting or refuting this recommendation based on bone quality are limited. We hypothesized that a "holiday" of 5 years would cause no major bone compositional changes.

METHODS

We analyzed the 31 available biopsies from the FLEX-Long-term Extension of FIT (Fracture Intervention Trial) using Fourier transform infrared imaging (FTIRI). Biopsies from two groups of post-menopausal women, a "Continuously treated group" (N = 16) receiving alendronate for ~ 10 years and a "Discontinued group" (N = 15), alendronate treated for 5 years taking no antiresorptive medication during the following 5 years. Iliac crest bone biopsies were provided at 10 years.

RESULTS

Key FTIRI parameters, mineral-to-matrix ratio, carbonate-to-phosphate ratio, acid phosphate substitution, and collagen cross-link ratio as well as heterogeneity of these parameters were similar for Continuously treated and Discontinued groups in age-adjusted models. The Discontinued group had 2% greater cortical crystallinity (p = 0.01), 31% greater cortical acid phosphate heterogeneity (p = 0.02), and 24% lower trabecular crystallinity heterogeneity (p = 0.02).

CONCLUSIONS

Discontinuation of alendronate for 5 years did not affect key FTIRI parameters, supporting the hypothesis that discontinuation would have little impact on bone composition. Modest differences were observed in three parameters that are not likely to affect bone mechanical properties. These preliminary data suggest that a 5-year BP holiday is not harmful to bone composition.

Hip fracture trends in the United States, 2002 to 2015

An analysis of United States (US) Medicare claims data from 2002 to 2015 for women aged ≥ 65 years found that age-adjusted hip fracture rates for 2013, 2014, and 2015 were higher than projected, resulting in an estimated increase of more than 11,000 hip fractures.

INTRODUCTION

Hip fractures are a major public health concern due to high morbidity, mortality, and healthcare expenses. Previous studies have reported a decrease in the annual incidence of hip fractures in the US beginning in 1995, coincident with the introduction of modern diagnostic tools and therapeutic agents for osteoporosis. In recent years, there has been less bone density testing and fewer prescriptions for osteoporosis treatments. The large osteoporosis treatment gap raises concern of possible adverse effects on hip fracture rates.

METHODS

We assessed hip fracture incidence in the US to determine if the previous decline in hip fracture incidence continued. Using 2002 to 2015 Medicare Part A and Part B claims for women ≥ 65 years old, we calculated age-adjusted hip fracture rates, weighting to the 2014 population.

RESULTS

We found that hip fracture rates declined each year from 2002 to 2012 and then plateaued at levels higher than projected for years 2013, 2014, and 2015.

CONCLUSIONS

The plateau in age-adjusted hip fracture incidence rate resulted in more than 11,000 additional estimated hip fractures over the time periods 2013, 2014, and 2015. We recommend further study to assess all factors contributing to this remarkable change in hip fracture rate and to develop strategies to reduce the osteoporosis treatment gap.

Inhibitory Effect of Purpurogallin on Osteoclast Differentiation in Vitro through the Downregulation of c-Fos and NFATc1

Purpurogallin, a benzotropolone-containing natural compound, has been reported to exhibit numerous biological and pharmacological functions, such as antioxidant, anticancer, and anti-inflammatory effects. In this study, we enzymatically synthesized purpurogallin from pyrogallol and investigated its role in receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis. Purpurogallin attenuated the formation of multinucleated tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts from bone marrow macrophages (BMMs) without causing cytotoxicity, and suppressed upregulation of osteoclast-specific markers, including TRAP (Acp5), cathepsin K (Ctsk), and dendritic cell-specific transmembrane protein (Dcstamp). However, purpurogallin did not affect the bone resorbing function of mature osteoclasts evident by the resorption pit assay. Activation of mitogen-activated protein kinases, Akt and IkB pathways in RANK signaling were not altered by purpurogallin, whereas the expression of c-Fos and NFATc1, key transcriptional regulators in osteoclastogenesis, was dramatically inhibited by purpurogallin. Purpurogallin also significantly reduced the expression level of B lymphocyte-induced maturation protein-1 (Blimp1) gene (Prdm1). Further, downregulation of Blimp1 led to forced expression of anti-osteoclastogenic genes, including interferon regulatory factor-8 (Irf8) and B-cell lymphoma 6 (Bcl6) genes. Taken together, our data suggested that purpurogallin inhibits osteoclast differentiation via downregulation of c-Fos and NFATc1.

Incidence Rate of Atypical Femoral Fracture after Bisphosphonates Treatment in Korea

BACKGROUND

Atypical femoral fracture (AFF) has been high-lightened, because it was associated with the long-term use of bisphosphonate. Comparing western countries, the incidence rate of AFF was unclear in East Asian patients. Our purposes were to estimate the incidence rate of radiologically defined AFF in Korea, and to determine the association between occurrence of AFF and long-term use of bisphosphonate.

METHODS

We conducted a hospital-based, retrospective cohort study in patients aged ≥ 45 years, who took bisphosphonate. The occurrence of AFF was estimated by using incidence rate, and the age-adjusted incidence rate to U.S. 2010 Census data. The association between occurrence of AFF and the duration of bisphosphonate use was examined. The cumulative probability of AFF was plotted per each duration of bisphosphonate use.

RESULTS

Among 10,338 individuals who took bisphosphonate, 13 patients with AFF following use of bisphosphonate were identified. The incidence rate was 85.9/100,000 person-years (95% confidence interval [CI], 50.2-146.9), and age-adjusted incidence rate was 72.7/100,000 person-years (95% CI, 29.1-175.8). In Poisson regression analysis, higher body mass index (BMI) was associated with an increased risk of AFF (relative risk, 1.2; 95% CI, 1.004-1.359). The cumulative probability of AFF increased abruptly when the duration of bisphosphonate use was 4 years or more.

CONCLUSION

Among Korean patients, the incidence rate of AFF was on a par with those of western countries, and this can provide basic information to conduct further studies by evaluating risk and benefit of continuing bisphosphonate.

Proceedings of the 2017 Santa Fe Bone Symposium: Insights and Emerging Concepts in the Management of Osteoporosis

The 18th Annual Santa Fe Bone Symposium was held on August 4-5, 2017, in Santa Fe, New Mexico, USA. The symposium convenes health-care providers and clinical researchers to present and discuss clinical applications of recent advances in research of skeletal diseases. The program includes lectures, oral presentations by endocrinology fellows, case-based panel discussions, and breakout sessions on topics of interest, with emphasis on participation and interaction of all participants. Topics included the evaluation and treatment of adult survivors with pediatric bone diseases, risk assessment and management of atypical femur fractures, nonpharmacologic strategies in the care of osteoporosis, and skeletal effects of parathyroid hormone with opportunities for therapeutic intervention. Management of skeletal complications of rheumatic diseases was discussed. Insights into sequential and combined use of antiresorptive agents were presented. Individualization of patient treatment decisions when clinical practice guidelines may not be applicable was covered. Challenges and opportunities with osteoporosis drug development were discussed. There was an update on progress of Bone Health TeleECHO (Bone Health Extension for Community Healthcare Outcomes), a teleconferencing strategy for sharing knowledge and expanding capacity to deliver best-practice skeletal health care.

1D Co(ii) coordination polymers based on cyclobutyl- and cyclopentyl-substituted zoledronate analogues: synthesis, structural comparison, thermal stability and magnetic properties

Competing magnetic exchange in 1a and 2a with predominant participation of antiferromagnetic interactions in 1a and ferromagnetic exchange in 2a.

Diffuse ocular and orbital inflammation after zoledronate infusion-case report and review of the literature

Bisphosphonates have become a commonly used class of medications to treat osteoporosis and other bone diseases. Zoledronate (zoledronic acid) can be dosed annually via intravenous infusion, making it an appealing option for patients and physicians. We report the case of a 68-year-old woman who developed severe, unilateral, ocular inflammation, including corneal endotheliitis, anterior uveitis with hyphema, scleritis, and orbital inflammation beginning 12 hours after receiving her first zoledronate infusion. Symptoms escalated but ultimately resolved with topical steroids and high-dose systemic corticosteroids. To our knowledge, this is the first report of unilateral diffuse inflammation of the eye and orbit, including corneal inflammation developing within 12 hours of a first zoledronate infusion.

Persistence with denosumab therapy in women affected by osteoporosis with fragility fractures: a multicenter observational real practice study in Italy

BACKGROUND

Persistence is commonly considered a key factor for the successful management of osteoporosis and fragility fractures. Denosumab is the first biologic agent developed for the treatment of osteoporosis with satisfying data regarding the persistence with this therapy.

AIM

The purpose of this multicenter observational real practice study was to evaluate the persistence with denosumab treatment in post-menopausal women affected by osteoporosis.

MATERIAL/SUBJECTS AND METHODS

Women were recruited in four specialized centers for the management of osteoporosis in North, Center and South of Italy. We included women with a diagnosis of post-menopausal osteoporosis, aged >50 years, able to obtain a prescription according to the Italian reimbursement criteria in force during the study period for anti-osteoporotic pharmacological treatment. They initiated a treatment with subcutaneous denosumab (Prolia^®) 60 mg/every 6 months between November 2011 and May 2016. Women who had received aromatase inhibitors were excluded. Patients were assessed at baseline and every 6 months for all treatment length. Persistence data were evaluated for a total of 36 months.

RESULTS

Eight hundred seventy women were enrolled; mean aged 70 years, with a mean body mass index of 24.8 ± 4.1 kg/m². At the Dual-energy X-ray absorptiometry assessment, the mean lumbar spine T-score was -2.76 ± 1.14 standard deviations (SD) and the mean femoral neck T-score was -2.49 ± 0.80 SD. During the study, the total persistence was 91.4%. Total dropouts were 75 (8.6%), higher within the initial 6-month period of treatment.

CONCLUSIONS

Persistence to denosumab treatment in our observational real practice study was very high. These results suggest that factors such as frequency of visits, pharmacological schedule, and opportunity to call the doctor might play an important role in the persistence and adherence to treatment to obtain maximum therapeutic effect and avoid further fragility fractures.

Emodin promotes the osteogenesis of MC3T3-E1 cells via BMP-9/Smad pathway and exerts a preventive effect in ovariectomized rats

Emodin, a natural anthraquinone extracted from the Chinese herbs rhubarb and giant knotweed rhizome, has been reported to enhance osteoblast differentiation. However, the mechanisms underlying its ability to regulate osteogenesis are unclear. The objective of this study was to determine the role of emodin in osteoblast function in vitro and its osteoprotective effect in vivo. Emodin enhanced the differentiation and mineralization of MC3T3-E1 cells, as evidenced by elevated alkaline phosphatase activity and increased number of mineralized nodules. In cultured osteoblasts, emodin significantly induced the mRNA expression of BMP-9 which is one of the least studied but most osteogenic bone morphogenetic proteins (BMPs). Furthermore, the bone morphogenetic protein receptor-Smad (BMPR-Smad) signaling axis and p38 mitogen activated protein kinase (p38 MAPK) were activated. The in vivo function of emodin were evaluated by assessing bone histomorphology, trabecular bone microarchitecture, mechanical properties of the skeleton, and serum parameters of bone turnover in ovariectomized (OVX) rats. Emodin combined with low-dose of estrogen improved trabecular bone microarchitecture in the fourth lumbar vertebra compared with low-dose estrogen alone and enhanced vertebral body strength. Moreover, emodin suppressed the OVX-induced elevation of serum osteocalcin (OC). In addition, there were fewer side effects on uterine hypertrophy with the combination therapy than with high-dose estrogen alone. However, emodin alone did not exert any osteoprotective effect. These results suggest that emodin may be a promising alternative agent for osteoporosis in combination therapy.

Psoralen stimulates osteoblast proliferation through the activation of nuclear factor-κB-mitogen-activated protein kinase signaling

Osteoporosis is a systemic skeletal disease that leads to increased bone fragility and susceptibility to fracture. Approximately 50% of postmenopausal women develop osteoporosis as a result of postmenopausal estrogen deficiency. To reduce fractures related to osteoporosis in women, previous studies have focused on therapeutic strategies that aim to increase bone formation or decrease bone resorption. However, pharmacological agents that aim to improve bone fracture susceptibility exhibit side effects. Current studies are investigating natural alternatives that possess the benefits of selective estrogen receptor modulators (SERMs) without the adverse effects. Recent studies have indicated that phytoestrogen may be an ideal natural SERM for the treatment of osteoporosis. In Chinese herbal medicine, psoralen, as the predominant substance of Psoralea corylifolia, is considered to be a phytoestrogen and is used as a remedy for osteoporosis. A number of studies have demonstrated the efficacy of psoralen in bone formation. However, the pathways and underlying molecular mechanisms that participate in psoralen-induced osteoblast formation are not well understood. In the present study, hFOB1.19 cells were treated with psoralen at different concentrations (0, 5, 10, 15 and 20 µM) for 0, 24, 36, 48 and 72 h, respectively. Reverse transcription-quantitative polymerase chain reaction and western blot assays were performed to detect glucose transporter 3 (GLUT3) expression. A cell counting kit-8 assay was used to analyze cell proliferation. In addition the effects of mitogen activated protein kinase inhibitors on extracellular signal-regulated kinase (ERK), phosphorylated (p)-ERK, p38, p-p38, c-Jun N-terminal kinase (JNK) and p-JNK expressions and cell proliferation were measured, as was the effect of nuclear factor (NF)-κB inhibitor on P65 and GLUT3 expressions and cell proliferation. The results indicated that psoralen stimulates hFOB1.19 cell proliferation in a dose-dependent manner (P<0.05). Phospho-ERK, p38 and JNK were markedly increased by psoralen compared with the control group (P<0.05), and the specific inhibitors of ERK (SCH772984), p38 (SB203580) and JNK (SP600125) reversed the stimulatory effects of psoralen on signal marker phosphorylation (P<0.05). The rate of psoralen-induced cell proliferation was significantly suppressed by inhibitors of ERK, JNK and p38 compared with psoralen treatment alone (P<0.05). In addition, psoralen stimulated osteoblast proliferation via the NF-κB signaling pathway. Therefore, the present findings suggest that psoralen may be a potential natural alternative to SERMs in the treatment of osteoporosis and fractures.

Sclerostin antibodies in osteoporosis: latest evidence and therapeutic potential

Sclerostin is an osteocyte-derived glycoprotein that inhibits Wnt/β-catenin signaling and activation of osteoblast function, thereby inhibiting bone formation. It plays a vital role in the regulation of skeletal growth. In adults, sclerostin secretion is modulated by skeletal loading (increased secretion with immobilization; less with weight bearing) and by hormonal/cytokine actions on the osteocyte. Sclerostin deficiency syndromes in humans and animals are characterized by high bone mass of normal quality. In animal models of osteoporosis, inhibition of sclerostin by monoclonal antibodies induces osteoblast activity and new bone formation, normalizing bone mass and improving bone architecture and strength. In recently completed clinical trials, anti-sclerostin antibody therapy results in marked increases in bone mineral density and rapid and substantial reduction in fracture risk. This review will focus on these recent studies and anticipate the role of anti-sclerostin therapy in the management of patients with osteoporosis.

The protective effect of berberine hydrochloride on LPS‑induced osteoclastogenesis through inhibiting TRAF6‑Ca2+‑calcineurin‑NFATcl signaling pathway

The present study investigated the protective effect of berberine hydrochloride on lipopolysaccharide (LPS) ‑induced acute bone destruction through inhibition of the TNF receptor associated factor 6 (TRAF6)‑Ca2+‑calcineurin‑nuclear factor of activated T‑cell 1 (NFATc1) signaling pathway. An osteoclast culture system of RAW264.7 cells induced by LPS in vitro was established. A polymerase chain reaction (PCR) assay was applied to determine the effect of berberine hydrochloride on the mRNA expression levels of fos‑related antigen 2 (Fra‑2), tartrate‑resistant acid phosphatase (TRAP), β3‑integrin, cathepsin K, dendritic cell‑specific transmembrane protein (DC‑STAMP), V‑type proton ATPase subunit d 2 (Atp6v0d2) and NFATcl. An ELISA assay was performed to measure the release of tumor necrosis factor‑α (TNF‑α). Western blot analysis was used to measure the effect of berberine hydrochloride on the expression of calcineurin in the LPS‑induced NFATc1 signaling pathway, as well as the expression levels of phosphoinositide phospholipase C‑γl (PLC‑γ1), toll like receptor 4 (TLR4) and TRAF6. The effect of berberine hydrochloride on Ca2+ concentration was detected using a confocal technique with a Flou‑3/acetoxymethyl ester Ca2+ probe. The PCR results demonstrated that berberine hydrochloride inhibited the mRNA expression levels of Fra‑2, TRAP, β3‑integrin, cathepsin K, DC‑STAMP, Atp6v0d2 and NFATc1. Furthermore, the ELISA results demonstrated that TNF‑α expression was decreased. The western blot analysis revelead that berberine hydrochloride treatment results in decreased expression levels of PLC‑γ1, TLR4 and TRAF6, and inhibition of Ca2+ influx. In conclusion, the results of the present study suggest that berberine hydrochloride targets TRAF6 and NFATc1, thus inhibiting osteoclastogenesis and bone destruction via inhibition of the TRAF6‑Ca2+‑calcineurin‑NFATcl signaling pathway.

Assessing the feasibility of the Effectiveness of Discontinuing Bisphosphonates trial: a pilot study

The Effectiveness of Discontinuing Bisphosphonates (EDGE) study is a planned pragmatic clinical trial to guide "drug holiday" clinical decision making. This pilot study assessed work flow and feasibility of such a study. While participant recruitment and treatment adherence were suboptimal, administrative procedures were generally feasible and minimally disrupted clinic flow.

INTRODUCTION

The comparative effectiveness of continuing or discontinuing long-term alendronate (ALN) on fractures is unknown. A large pragmatic ALN discontinuation study has potential to answer this question.

METHODS

We conducted a 6-month pilot study of the planned the EDGE study among current long-term ALN users (women aged ≥65 with ≥3 years of ALN use) to determine study work flow and feasibility including evaluating the administrative aspects of trial conduct (e.g., time to contract, institutional review board (IRB) approval), assessing rates of site and participant recruitment, and evaluating post-randomization outcomes, including adherence, bisphosphonate-associated adverse events, and participant and site satisfaction. We assessed outcomes 1 and 6 months after randomization.

RESULTS

Nine sites participated, including seven community-based medical practices and two academic medical centers. On average (SD), contract execution took 3.4 (2.3) months and IRB approval took 13.9 (4.1) days. Sites recruited 27 participants (13 to continue ALN and 14 to discontinue ALN). Over follow-up, 22% of participants did not adhere to their randomization assignment: 30.8% in the continuation arm and 14.3% in the discontinuation arm. No fractures or adverse events were reported. Sites reported no issues regarding work flow, and participants were highly satisfied with the study.

CONCLUSIONS

Administrative procedures of the EDGE study were generally feasible, with minimal disruption to clinic flow. In this convenience sample, participant recruitment was suboptimal across most practice sites. Accounting for low treatment arm adherence, a comprehensive recruitment approach will be needed to effectively achieve the scientific goals of the EDGE study.

High and pointed type of femoral localized reaction frequently extends to complete and incomplete atypical femoral fracture in patients with autoimmune diseases on long-term glucocorticoids and bisphosphonates

Once a localized reaction (beaking) was detected, discontinuation of bisphosphonates (BPs) and switching to vitamin D supplementation or teriparatide therapy effectively improved its shape. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete atypical femoral fracture increased and consideration of prophylactic fixation for such patients was required.

INTRODUCTION

Femoral localized reaction (localized periosteal thickening of the lateral cortex, beaking) is reported to precede atypical femoral fractures (AFFs) and to develop in 8-10% of patients with autoimmune diseases taking BPs and glucocorticoids. The aims of the present study were to retrospectively investigate the shapes of localized reaction to consider how to manage the condition.

METHODS

Twenty femora of 12 patients with autoimmune diseases who were on BPs and glucocorticoids exhibited femoral localized reaction. The heights of localized reaction were measured and the shapes classified as pointed, arched, and other. Localized reaction changes were divided into three categories: deterioration, no change, and improvement. A severe form of localized reaction was defined; this was associated with prodromal pain, de novo complete AFF, or incomplete AFF with a fracture line at the localized reaction.

RESULTS

The mean height of localized reaction was 2.3 ± 0.8 mm (range, 1.0-3.7 mm) and the pointed type was 35%. Localized reaction was significantly higher (3.3 ± 0.8 vs. 2.1 ± 0.7 mm; p = 0.003) and the pointed type more common (78 vs. 27%; p = 0.035) in those with the severe form of localized reaction. Seven patients with localized reactions discontinued BPs just after localized reaction was detected, but five continued on BPs for 2 years. Localized reaction deterioration was more common in patients who continued than discontinued BPs (100 vs. 29%; p = 0.027). After 2 years, all patients had discontinued BPs and localized reaction did not deteriorate further in any patient.

CONCLUSIONS

Once a localized reaction was detected, discontinuation of BPs and switching to vitamin D supplementation or teriparatide therapy effectively improved it. When the localized reaction was high, of the pointed type, and/or accompanied by prodromal pain, the risks of complete and incomplete AFF increased and consideration of prophylactic fixation for such patients was required.

Evaluation of a "Just-in-Time" Nurse Consultation on Bone Health: A Pilot Randomized Controlled Trial

CONTEXT

Evidence is inconclusive whether a nurse consultation can improve osteoporosis-related patient outcomes.

OBJECTIVE

To evaluate whether a nurse consultation immediately after dual-energy x-ray absorptiometry (DXA) produced better osteoporosis-related outcomes than a simple intervention to activate adults in good bone health practices or usual care.

DESIGN

Pilot randomized controlled trial, conducted within the larger Patient Activation After DXA Result Notification (PAADRN) trial (NCT01507662). After DXA, consenting adults age 50 years or older were randomly assigned to 3 groups: nurse consultation, PAADRN intervention (mailed letter with individualized fracture risk and an educational brochure), or usual care (control). Nurse consultation included reviewing DXA results, counseling on bone health, and ordering needed follow-up tests or physician referrals.

MAIN OUTCOME MEASURES

Change from baseline to 52 weeks in participant-reported osteoporosis-related pharmacotherapy, lifestyle, activation and self-efficacy, and osteoporosis care satisfaction.

RESULTS

Nurse consultation participants (n = 104) reported 52-week improvements in strengthening and weight-bearing exercise (p = 0.09), calcium intake (p < 0.01), osteoporosis knowledge (p = 0.04), activation (p < 0.01), dietary self-efficacy (p = 0.06), and osteoporosis care satisfaction (p < 0.01). Compared with PAADRN intervention participants (n = 39), nurse consultation participants had improved dietary self-efficacy (p = 0.07) and osteoporosis care satisfaction (p = 0.05). No significant improvements in osteoporosis-related outcomes were achieved vs PAADRN controls (n = 70).

CONCLUSION

"Just-in-time" nurse consultation yielded a few improvements over 52 weeks in osteoporosis-related outcomes; however, most changes were not different from those obtained through the lower-cost PAADRN intervention or usual care.

Western Osteoporosis Alliance Clinical Practice Series: Evaluating the Balance of Benefits and Risks of Long-Term Osteoporosis Therapies

Osteoporosis is a chronic disease that requires life-long strategies to reduce fracture risk. Few trials have investigated the balance of benefits and risk with long-term use of osteoporosis therapies, and fewer still have investigated the consequences of treatment discontinuation. The best available evidence suggests that up to 10 years of treatment with an oral bisphosphonate maintains the degree of fracture risk reduction observed in the 3-year registration trials. With denosumab, 10 years of therapy appears to provide fracture risk reduction similar to or better than that observed in the 3-year registration trial. Available data suggest an increasing but low risk of fractures with atypical features with increasing duration of bisphosphonate therapy. Published data linking duration of therapy to osteonecrosis of the jaw are lacking for bisphosphonates and denosumab. Other side effects associated with denosumab or bisphosphonates do not appear to be related to therapy duration. The antifracture benefits of long-term therapy with bisphosphonates and denosumab in appropriately selected patients outweigh the low risk of serious side effects.

The zebrafish operculum: A powerful system to assess osteogenic bioactivities of molecules with pharmacological and toxicological relevance

Bone disorders affect millions of people worldwide and available therapeutics have a limited efficacy, often presenting undesirable side effects. As such, there is a need for novel molecules with bone anabolic properties. The aim of this work was to establish a rapid, reliable and reproducible method to screen for molecules with osteogenic activities, using the zebrafish operculum to assess bone formation. Exposure parameters were optimized through morphological analysis of the developing operculum of larvae exposed to calcitriol, a molecule with known pro-osteogenic properties. An exposure of 3days initiated at 3days post-fertilization was sufficient to stimulate operculum formation, while not affecting survival or development of the larvae. Dose-dependent pro- and anti-osteogenic effects of calcitriol and cobalt chloride, respectively, demonstrated the sensitivity of the method and the suitability of the operculum system. A double transgenic reporter line expressing fluorescent markers for early and mature osteoblasts was used to gain insights into the effects of calcitriol and cobalt at the cellular level, with osteoblast maturation shown to be stimulated and inhibited, respectively, in the operculum of exposed fish. The zebrafish operculum represents a consistent, robust and rapid screening system for the discovery of novel molecules with osteogenic, anti-osteoporotic or osteotoxic activity.

Moxibustion treatment for primary osteoporosis: A systematic review of randomized controlled trials

Primary osteoporosis (POP) has a serious impact on quality of life for middle-aged and elderly, which particularly increase the risk of fracture. We conducted the systematic review to evaluate the effects of moxibustion for POP in randomized controlled trials (RCTs).Eight databases were searched from their inception to July 30, 2016. The RCTs reporting the moxibustion as a monotherapy or in combination with conventional therapy for POP were enrolled. The outcomes might be fracture incidence, quality of life, clinical symptoms, death attributed to osteoporosis, adverse effect, bone mineral density (BMD), and biochemical indicators. Literature selection, data abstraction, quality evaluation, and data analysis were in accordance with Cochrane standards.Thirteen trials including 808 patients were included. Meta-analysis was not conducted because of the obvious clinical or statistical heterogeneity. Limited evidence suggested that moxibustion plus anti-osteoporosis medicine might be more effective in relieving the pain (visual analogue scale scores average changed 2 scores between groups, 4 trials), increasing the BMD of femoral neck (average changed 0.4 g/cm2 between groups, 3 trials), and improving the level of bone gla protein, osteoprotegerin and bone alkaline phosphatase (2 trials) compared with anti-osteoporosis medicine alone. However, the quality of previous studies was evaluated as generally poor. The safety evidence of moxibustion was still insufficient. Due to the paucity of high-quality studies, there was no definite conclusion about the efficacy and safety of moxibustion treating POP although parts of positive results were presented. Future research should pay attention to the dose-response relation and fracture incidence of moxibustion for POP.

Oral administration of kaempferol inhibits bone loss in rat model of ovariectomy-induced osteopenia

BACKGROUND

Postmenopausal osteoporosis and osteoporotic fractures constitute an increasing problem in developing countries. Kaempferol, isolated from seeds of Cuscuta chinensis, is an active flavonoid inhibiting in vitro osteoclast activity. The aim of the presented research was an assessment of kaempferol effect on estrogen-deficiency-induced bone structure disturbances in rats.

METHODS

The study was performed on 24 Wistar female rats divided into 3 groups: SHAM - rats undergoing a "sham" surgery, OVX-C - control group of animals that underwent ovariectomy, OVX-K - rats undergoing ovariectomy and receiving kaempferol for 8 weeks (from day 56 to day 112).

RESULTS

In the OVX-K group, contrary to the OVX-C one, there was no significant decrease in femoral bone mineral density (BMD). A significant increase in Young's modulus was observed in the OVX-K group compared to the OVX-C (15.33±2.51GPa vs. 11.14±1.93GPa, p<0.05). A decreased bone turnover was detected in the OVX-K group. Tissue volume ratio (BV/TV) and trabecular bone perimeter were increased in the OVX-K group compared to the OVX-C one (0.241±0.037 vs. 0.170±0.022, p<0.05 and 15.52±2.78mm vs. 9.67±3.07mm, p<0.05, respectively).

CONCLUSION

Kaempferol has a beneficial influence on estrogen-deficiency-induced disturbances of bone structure in rats.

Importance of prompt antiresorptive therapy in postmenopausal women discontinuing teriparatide or denosumab: The Denosumab and Teriparatide Follow-up study (DATA-Follow-up)

When teriparatide and denosumab are discontinued, bone mineral density (BMD) abruptly decreases. To compare rates of bone loss in postmenopausal women who discontinue denosumab or teriparatide and receive no additional prescription osteoporosis medications to women who discontinue these drugs followed by prompt antiresorptive therapy, we asked women concluding the Denosumab and Teriparatide Administration (DATA) study and its extension, DATA-Switch, to return for BMD measurements 1-2years after study completion. In these studies, women received 2-years of either teriparatide, denosumab or both medications followed by 2-years of the alternate therapy (women who received combination therapy initially received an additional 2-years of denosumab alone). Fifty of 69 women who completed DATA-Switch returned after a mean of 15.4±3.5months. Of the 28 women who received antiresorptive therapy (10 denosumab, 10 oral bisphosphonates, 8 intravenous zoledronic acid), the mean interval between ending DATA-Switch and beginning antiresorptive therapy was 3.8±3.1months. In the 22 women not receiving follow-up therapy, femoral neck, total hip, and spine BMD decreased by -4.2±4.3%, -4.5±3.6%, and -10.0±5.4%, respectively, while BMD was maintained in those who did receive follow-up antiresorptive drugs (femoral neck, total hip, and spine BMD changes of -0.6±2.7%, -0.8±3.1%, and -1.2±4.7%, respectively, P<0.001 for all between-group comparisons). Among untreated women, femoral neck BMD decreased more in those discontinuing denosumab (-5.8±4.0%) than in those discontinuing teriparatide (-0.8±2.6%, P=0.008). Total hip BMD, but not spine BMD, showed a similar pattern. Among treated women, denosumab increased femoral neck and total hip BMD more than bisphosphonates while BMD changes at the spine did not differ significantly. In summary, the large teriparatide and denosumab-induced gains in BMD achieved with 4years of intensive therapy in the DATA and DATA-Switch studies were maintained in patients who received prompt antiresorptive therapy but not in those left untreated. These results demonstrate the negative consequences of delaying consolidation therapy in women treated with these drugs and underscore the importance of timely medication transitions in such patients.

Observations following discontinuation of long-term denosumab therapy

Stopping denosumab after 8 years of continued treatment was associated with bone loss during a 1-year observation study in patients who were not prescribed osteoporosis treatment. Bone loss was attenuated in patients who began another osteoporosis therapy. Treatment to prevent bone loss upon stopping denosumab should be considered.

INTRODUCTION

This study aimed to understand osteoporosis management strategies during a 1-year observational follow-up after up to 8 years of denosumab treatment in a phase 2 study.

METHODS

During the observational year, patients received osteoporosis management at the discretion of their physician and returned to the clinic for BMD assessment and completion of an osteoporosis management questionnaire. Incidence of serious adverse events and fractures was collected. Analyses were descriptive.

RESULTS

Of 138 eligible patients, 82 enrolled in and completed the observation study. Most (65 [79%]) did not receive prescription osteoporosis medication, with "my doctor felt I no longer needed a medication" being the most common reason (23 [35%]). Of the 17 patients who took osteoporosis medications, 8 discontinued therapy during the observation study. In patients treated with denosumab for 8 years (N = 52), BMD decreased during the 1-year observation study (6.7% [lumbar spine], 6.6% [total hip]). Those who took osteoporosis medication during the observation study showed a smaller decline in BMD than those who did not. No new safety concerns were identified. Eight patients (9.8%), all of whom had at least one predisposing risk factor, experienced 17 fractures. This included seven patients who experienced one or more vertebral fractures.

CONCLUSIONS

Consistent with denosumab's mechanism of action, treatment cessation led to reversal of the drug's effect on BMD and perhaps fracture risk. For patients who took osteoporosis therapy, bone loss was attenuated. For patients at high fracture risk, switching to another osteoporosis therapy if denosumab is discontinued seems appropriate.

Treatment of postmenopausal osteoporosis: a literature-based algorithm for use in the public health care system

Bisphosphonates are considered first-line agents in the treatment of postmenopausal osteoporosis based on extensive experience of use, safety, and proven efficacy in reducing vertebral, non-vertebral and femur fractures. However, post-marketing reports based on the treatment of millions of patients/year over lengthy periods of time have revealed the occurrence of initially unexpected adverse effects, such as osteonecrosis of the jaw and atypical femoral fracture, leading to the restriction of treatment duration with bisphosphonates by global regulatory agencies. However, despite the association between these effects and bisphosphonates, this risk should be analyzed in the context of osteoporosis treatment, alongside the benefit of preventing osteoporotic fractures and their clinical consequences. Therefore, we consider it plausible to discuss the restriction to the use of bisphosphonates, possible indications for prolonged treatment and alternative therapies following the suspension of this drug class for patients with persistent high risk of fracture after initial treatment, especially considering the problems of public health funding in Brazil and the shortage of drugs provided by the government. Thus, to standardize the treatment of osteoporosis in the public health care system, we aim to develop a proposal for a scientifically-based pharmacological treatment for postmenopausal osteoporosis, establishing criteria for indication and allowing the rational use of each pharmacological agent. We discuss the duration of the initial bisphosphonate treatment, the therapeutic options for refractory patients and potential indications of other classes of drugs as first-choice treatment in the sphere of public health, in which assessing risk and cost effectiveness is a priority.

Prevention and management of glucocorticoid-induced side effects: A comprehensive review: A review of glucocorticoid pharmacology and bone health

Systemic glucocorticoids are an essential therapy for a range of conditions, but their multiple side effects can produce significant morbidity for patients. The objective of this review is to discuss these side effects while addressing 3 questions: 1) What dose and duration of glucocorticoid therapy should prompt concern for individual side effects?; 2) How should clinicians counsel patients about these complications?; and 3) How can these problems be prevented or managed? To accomplish these objectives, we have created a series of tables and algorithms based on a review of relevant data to guide counseling, prophylaxis, and management of 11 glucocorticoid side effects. The first article in this 4-part continuing medical education series begins with a review of glucocorticoid pharmacology followed by a discussion of bone health (ie, osteoporosis and osteonecrosis).

Recognition and treatment of postmenopausal osteoporosis

Osteoporosis is a common but often silent condition among older adults. The characteristic pathological changes associated with osteoporosis may go unnoticed until a fracture occurs or a bone density test is performed. Although osteoporosis occurs in men and among premenopausal women, it is most prevalent among postmenopausal women who are the focus of this article. Within the subpopulation of postmenopausal women, there are major differences in risk status, disease severity, and response to treatment. Two individual examples are presented to highlight these differences and to illustrate appropriate assessment and treatment strategies in each scenario. In addition, general nonpharmacological recommendations for postmenopausal women across risk status and disease severity are presented.

Osteoporosis: Treat-to-Target

PURPOSE OF REVIEW

Treat-to-target (goal-directed therapy) has been proposed as a strategy to assist clinicians in selecting the most appropriate initial treatment for osteoporosis and guiding subsequent decisions to continue, change, or stop treatment. This is a review of the current medical evidence regarding treatment targets and potential clinical applications in managing patients with osteoporosis.

RECENT FINDINGS

Analyses of randomized placebo-controlled trials of approved agents to treat osteoporosis have generally shown that larger increases in bone mineral density are associated with greater reduction in fracture risk. Achievement of T-scores > -2.5 to -2.0 with treatment appears to provide little additional fracture protection. The paradigm of treat-to-target is aimed at enhancing and individualizing the care of patients with osteoporosis. Based on the best available data, the most promising target is T-score > -2.5. More data are needed to validate the clinical utility of treat-to-target for osteoporosis.

Bisphosphonate-Functionalized Imaging Agents, Anti-Tumor Agents and Nanocarriers for Treatment of Bone Cancer

Bone metastases result from the invasion of primary tumors to bone. Current treatment modalities include local treatments such as surgery and radiotherapy, while systemic treatments include chemotherapy and (palliative) treatment of skeletal metastases. Nevertheless, once bone metastases have been established they remain incurable leading to morbidity and mortality. Bisphosphonates are a well-established class of drugs, which are increasingly applied in the treatment of bone cancers owing to their effective inhibition of tumor cells and suppression of bone metastases. The increased understanding of the mechanism of action of bisphosphonates on bone and tumor cells has prompted the development of novel bisphosphonate-functionalized imaging and therapeutic agents. This review provides an update on the preclinical efficacy of bisphosphonate-functionalized fluorophore, anti-tumor agents and nanocarriers for the treatment of bone metastases. After an overview of the general characteristics of bisphosphonates and their mechanisms of action, an outline is provided on the various conjugation strategies that have become available to functionalize imaging agents, anti-tumor agents and nanocarriers with bisphosphonates. Finally, the efficacy of these bisphosphonate-modified agents and carriers in preclinical studies is evaluated by reviewing their potential to target tumors and inhibit tumor growth in clinically relevant animal models for the treatment of bone cancer.

Intravenous Zoledronic Acid 5 mg on Bone Turnover Markers and Bone Mineral Density in East China Subjects with Newly Diagnosed Osteoporosis: A 24-month Clinical Study

OBJECTIVE

This randomized, double-blind, placebo-controlled study assessed the necessity of early intervention, safety and efficacy of intravenous zoledronic acid 5 mg/year in East China women with newly diagnosed osteoporosis at high risk of fracture during a 24-month treatment period.

METHODS

Subjects (57 [52-62] years old) were randomized 3:2 to zoledronic acid versus placebo (randomized at baseline, zoledronic acid [175 cases], placebo-zoledronic acid [110 cases]). The bone mineral density of the lumbar spine and total hip was measured every 6 months with the use of dual-energy X-ray absorptiometry. Serum procollagen I N-terminal pro-peptide (PINP) and serum C-telopeptide of type I collagen (CTX) levels were measured every 6 months. The primary end point was the rate of change in the bone mineral density at the posteroanterior spine.

RESULTS

For subjects with measurements at 24 months, zoledronic acid significantly increased bone mineral density (BMD) at the lumbar spine (mean percent change ± SD, zoledronic acid 5.390% ± 0.854% versus placebo-zoledronic acid -1.038% ± 0.599%), the total hip (zoledronic acid 1.900% ± 0.262% versus placebo-zoledronic acid -1.631% ± 0.649%). Serum procollagen I N-terminal pro-peptide (PINP) and CTX decreased rapidly with zoledronic acid 5 mg treatment (P < 0.001 versus placebo at 6 month and 24 months) and changed from baseline in the zoledronic acid 5 mg and placebo-zoledronic acid 5 mg at 6 months by a mean of -66.348% and -75.375%, respectively (P < 0.001), and at 24 months by -49.950% and -52.325%, respectively (P < 0.001). No cases of serious adverse events were observed in two groups. Headache, pyrexia and myalgia occurred more commonly within the first 3 days after infusion with zoledronic acid 5 mg than with placebo (13.7% versus 2.1%, P = 0.0018; 28.0% versus 3.2%, P < 0.001; 21.7% versus 4.2%, P < 0.001, respectively).

CONCLUSIONS

These data show that early application of zoledronic acid 5 mg/year was well stimulated and tolerated for bone mass in newly diagnosed east china subjects with osteoporosis in a 24-month treatment.

Anti-osteoporotic treatments in France: initiation, persistence and switches over 6 years of follow-up

Limited information is available on anti-osteoporotic treatment initiation patterns in France. In 2006-2013, the most frequently prescribed first-line treatment class for osteoporosis was represented by bisphosphonates (alendronic acid and risedronic acid), followed by strontium ranelate. Persistence with anti-osteoporotic treatment was low, with high proportions of treatment discontinuations and switches.

INTRODUCTION

This epidemiological, longitudinal study described first-line treatment initiation, persistence, switches to second-line treatment, and medical care consumption in osteoporotic patients in France during the 2007-2013 period.

METHODS

Patients aged ≥50 years, who were recorded in a French claims database and did not die during the observation period, were included if they met ≥1 inclusion criteria for osteoporosis in 2007 (≥1 reimbursement for anti-osteoporotic treatment, hospitalisation for osteoporotic fracture (spine, hip, femur, forearm bones, humerus, wrist), or ≥1 reimbursement for long-term osteoporosis-associated status). We collected data on consumption of anti-osteoporotic treatment (alendronic acid, ibandronic acid, risedronic acid, zoledronic acid, raloxifene, strontium ranelate, teriparatide) and of osteoporosis-related medical care after the date of first reimbursement for anti-osteoporotic treatment.

RESULTS

We obtained 2219 patients with a 6-year follow-up and 1387 who initiated an anti-osteoporotic treatment in 2007 and who can be selected for the treatment regimen analysis. The most frequently used first-line treatments were alendronic acid (32.7 %), risedronic acid (22.4 %), strontium ranelate (19.3 %), ibandronic acid (13.1 %) and raloxifene (12.2 %). Among patients who received these treatments, the highest persistence after 6 years was observed for raloxifene (37.3 %), alendronic acid (35.1 %) and risedronic acid (32.3 %). Treatment discontinuations were reported for 35.5 % (raloxifene) to 53.4 % (strontium ranelate) and treatment switches for 27.4 % (alendronic acid) to 56.6 % (ibandronic acid) of these patients.

CONCLUSIONS

This study showed that persistence with anti-osteoporotic treatment was relatively low in France, with high proportions of treatment discontinuations and switches, and that patients with osteoporosis were insufficiently monitored by bone specialists.

Association between bisphosphonate therapy and outcomes from rehabilitation in older people

BACKGROUND

Bisphosphonate therapy may have actions beyond bone, including effects on cardiovascular, immune and muscle function. We tested whether bisphosphonate treatment is associated with improved outcomes in older people undergoing inpatient rehabilitation.

METHODS

Analysis of prospectively collected, linked routine clinical datasets. Participants were divided into never users of bisphosphonates, use prior to rehabilitation only, use after rehabilitation only, and current users (use before and after rehabilitation). We calculated change in 20-point Barthel scores during rehabilitation, adjusting for comorbid disease and laboratory data using multivariable regression analysis. Cox regression analyses were performed to analyse the association between bisphosphonate use and time to death or hospitalisation.

RESULTS

2797 patients were included in the analysis. Current bisphosphonate users showed greater improvement in Barthel score during rehabilitation than non-users (5.0 points [95%CI 4.3-5.7] vs 3.8 [95%CI 3.6-3.9]), but no difference compared to those receiving bisphosphonates only after discharge (5.1 [95%CI 4.6-5.5]). Previous bisphosphonate use was significantly associated with time to death (adjusted hazard ratio 1.41 [95%CI 1.15-1.73]) but less strongly with time to combined endpoint of hospitalisation or death (adjusted hazard ratio 1.18 [95%CI 0.98-1.48]). Use after discharge from rehabilitation was associated with reduced risk of death (adjusted hazard ratio 0.64 [95%CI 0.55-0.73]; hazard ratio per year of bisphosphonate prescription 0.98 [95%CI 0.97-0.99]).

CONCLUSION

Bisphosphonate use is unlikely to be causally associated with improved physical function in older people, but continuing use may be associated with lower risk of death.

Denosumab for the treatment of osteoporosis

Denosumab, a specific inhibitor of RANK ligand, is a novel therapy for postmenopausal osteoporosis and related disorders. An extensive clinical development program has evaluated the clinical efficacy and safety of denosumab with several thousand patients being followed for up to 10 years. Combined with more than six years of postmarketing experience, these studies provide substantial confidence that denosumab is a convenient and appropriate treatment for patients, including Asians, at high risk for fracture. This review will summarize the clinical development of denosumab and lessons learned since its approval for clinical use in 2010.

Outcomes between older adults with atypical and typical femoral fractures are comparable

INTRODUCTION

Atypical femoral fractures (AFFs) are rare but a serious complication associated with prolonged use of bisphosphonates. However little is known about clinical outcomes of AFFs. The aim of this study is to compare the characteristics and postoperative outcomes between older patients with AFFs and typical femoral fractures (TFFs).

METHODS

A retrospective matched cohort study (each AFF was age- and sex-matched with three TFFs) of patients aged 65 years or older who were admitted to The Queen Elizabeth Hospital, South Australia between January 2011 and December 2013 was undertaken. Baseline characteristics of both groups were compared. The primary outcomes evaluated were level of independence in mobility at discharge and 3 months after surgery. Secondary outcomes included length of hospital stay, post-operative complications, rate of surgical revision, discharge destination (after acute hospital stay or rehabilitation), 28-day hospital readmission and 12-month mortality.

RESULTS

Ten patients (mean age: 78.1 years) with AFFs were compared with 30 matched TFFs. Patients with AFFs were predominantly female (90%) and 80% had been taking oral bisphosphonate. Nine of the AFFs had their fractures fixed with an intramedullary (IM) nail. The level of independent mobility at discharge (OR 0.31; 95%CI: 0.06-1.71; p=0.26) and at 3 months (OR 0.51; 95%CI: 0.10-2.53; p=0.47) were comparable between the two groups. Only one AFF patient treated with plate and screws required surgical revision, compared with none in the TFF group. Secondary outcomes were not significantly different between the two groups.

CONCLUSION

Recovery of mobility and reoperation rates after surgery of patients with AFFs were favourable and did not differ significantly from TFFs. Further consideration should be given to using IM fixation in the management of AFFs in older people.

Epidemiology and Postoperative Outcomes of Atypical Femoral Fractures in Older Adults: A Systematic Review

OBJECTIVE

To review the literature on epidemiology and postoperative outcomes particularly surgical, functional and quality of life of atypical femoral fractures (AFFs) in the older population (aged ≥65 years) using the first and second American Society of Bone Mineral Research (ASBMR) Task Force consensus definition.

METHODS

Electronic search for articles on AFFs and bisphosphonates published in English was performed. Eligible studies were reviewed systematically in relation to (a) the epidemiology of AFFs in older people and (b) postoperative outcomes of AFFs.

RESULTS

Twenty-three studies on AFFs were included: 14 on epidemiology and 11 on treatment outcomes (two articles reported on both aspects). The epidemiological studies showed that the incidence of AFFs is low (3.0-9.8 per 100,000 person-years) but relative risk increased with longer duration of bisphosphonates use, especially after more than three years. Most cases of AFFs occurred in older people aged 65 years and above. However, in six studies, the mean age of patients with bisphosphonate-related AFFs is younger than those with typical proximal femoral fractures (mean age range of 66-75 years versus 75-89 years respectively). Varying postoperative and functional outcomes have been reported but differences in study population, management approaches and endpoints may account for these variations. For incomplete AFFs, prophylactic surgical intervention is potentially beneficial.

CONCLUSION

The benefits of bisphosphonates in reducing osteoporotic fractures still outweigh the risk of AFFs in view of its low absolute risk, when the ASBMR Task Force criteria for this type of fracture were applied. The risk of AFFs in different age groups is not well defined but tends to affect the younger patients more (aged <65 years) as compared to the older population (aged ≥65 years). Evidence supporting different types of treatment in AFFs such as intramedullary or extramedullary surgical devices and the use of teriparatide, a parathyroid hormone analogue, is not yet well established.

Bisphosphonates in the treatment of osteoporosis: a review of skeletal safety concerns

The use of bisphosphonates in treatment of osteoporosis declined significantly over the past decade. There is currently great concern, among patients and physicians, about two potential skeletal adverse effects associated with bisphosphonates- jaw osteonecrosis and atypical femur fractures. This has become a major public health issue since untreated osteoporosis carries a significant burden in terms of fracture-related morbidity and mortality, and bisphosphonates, considered first-line therapy for osteoporosis, have established efficacy in fracture and mortality reduction. Areas covered: In this review we discuss current literature on osteonecrosis of the jaw and atypical femur fractures in patients with osteoporosis treated with bisphosphonates, including case definition, pathogenesis, epidemiology, risk factors, clinical presentation, management and prevention. We conducted a literature search using PubMed and PubMed Central, using the search terms 'bisphosphonates', 'osteonecrosis of the jaw', and 'atypical fractures'. We selected relevant articles including meta-analyses, clinical trials, observational studies, and major society guidelines published between 2010 and 2016, to be included in this review. A few articles published prior to 2010 were also included as references. Expert commentary: The rare skeletal side effects of bisphosphonates should not preclude their use in patients with osteoporosis and high fracture risk, as benefits significantly outweigh the risks.

Dendritic polyglycerol anions for the selective targeting of native and inflamed articular cartilage

Dye-conjugated polyanions show high affinities toward native and inflamed cartilage dependent on the anionic moiety and the condition of the tissue.

Examination of the foreign body response to biomaterials by nonlinear intravital microscopy

Implanted biomaterials often fail because they elicit a foreign body response (FBR) and concomitant fibrotic encapsulation. To design clinically relevant interference approaches, it is crucial to first examine the FBR mechanisms. Here, we report the development and validation of infrared-excited nonlinear microscopy to resolve the three-dimensional (3D) organization and fate of 3D-electrospun scaffolds implanted deep into the skin of mice, and the following step-wise FBR process. We observed that immigrating myeloid cells (predominantly macrophages of the M1 type) engaged and became immobilized along the scaffold/tissue interface, before forming multinucleated giant cells. Both macrophages and giant cells locally produced vascular endothelial growth factor (VEGF), which initiated and maintained an immature neovessel network, followed by formation of a dense collagen capsule 2-4 weeks post-implantation. Elimination of the macrophage/giant-cell compartment by clodronate and/or neutralization of VEGF by VEGF Trap significantly diminished giant-cell accumulation, neovascularization and fibrosis. Our findings identify macrophages and giant cells as incendiaries of the fibrotic encapsulation of engrafted biomaterials via VEGF release and neovascularization, and therefore as targets for therapy.

The effect of sequential therapy for postmenopausal women with osteoporosis: A PRISMA-compliant meta-analysis of randomized controlled trials

BACKGROUND

Osteoporosis, more likely to occur in postmenopausal women, is a chronic condition that usually requires a long-term treatment strategy, but the use of either antiresorptive or anabolic drugs should be limited to 18 to 24 months. Discontinuing antiosteoporosis drugs may result in rapidly declining bone mineral density (BMD). Therefore, many patients are treated with the sequential use of 2 or more drugs. However, whether switching treatment from anabolic to antiresorptive drugs or the reverse could maintain or further increase BMD; and whether the sequential therapy could outperform the monotherapy under the same treatment duration still remains unclear. Nowadays, no firm conclusions were drawn.

METHODS

We searched Medline, Embase, and Cochrane Library from January 1, 1974 until February 1, 2016 to identify all randomized controlled trials for evaluating the effectiveness of sequential therapy of antiresorptive and anabolic drugs in postmenopausal osteoporosis women with the BMD changes of lumbar spine, femoral neck, and total hip as the outcomes. We evaluated the methodological quality and abstracted relevant data according to the Cochrane Handbook.

RESULTS

Eight trials involving 1509 patients were included. The pooled data showed that after switching treatment, the alternative drugs maintained the BMD and significantly increased the percentage change in BMD at the lumbar spine (MD, 3.59; 95% CI, 2.26-4.93), femoral neck (MD, 1.44; 95% CI, 0.60-2.27), and total hip (MD, 1.24; 95% CI, -0.12 to 2.60), although change in BMD was not significantly increased at the total hip. The sequential therapy significantly increased BMD from baseline at the lumbar spine (SMD, 0.59; 95% CI, 0.26-0.91), femoral neck (SMD, 0.22; 95% CI, 0.06-0.37), and total hip (SMD, 0.28; 95% CI, 0.01-0.56).

CONCLUSIONS

After switching treatment, sequential therapy further increased BMD. The sequential therapy showed a more significant improvement in BMD compared with any anti-resorptive drug given for the same treatment duration and was as effective as anabolic drugs. Thus, sequential therapy may be recommended as an effective treatment for osteoporotic women. However, more randomized controlled trials are still needed to determine the best sequence and the most appropriate drugs of sequential therapy.

Crocin inhibits RANKL-induced osteoclast formation and bone resorption by suppressing NF-κB signaling pathway activation

Crocin is a dietary compound with antioxidant and anti-inflammatory properties, but its effects on bone resorption have not been well characterized. Here we address this issue by examining the direct effects of crocin on osteoclast cells in vitro. Osteoclastogenesis was induced by RANKL (receptor activator of NF-κB ligand) in mouse bone marrow-derived macrophages in the absence or presence of crocin at various concentrations. Further, the bone resorption activity of mature osteoclast treated with crocin was assessed by pit assay. Without altering cell viability, crocin was shown to inhibit the differentiation and function of osteoclast cells in a dose-dependent manner. Mechanistically, RANKL-induced NF-κB and NFATc1 activation, the critical signaling pathways for osteoclast differentiation and function, were both repressed by crocin in bone marrow-derived macrophages. Thus, crocin suppresses osteoclastogenesis through direct inhibition of intracellular molecular pathways, which may contribute to future development of anti-bone resorption treatment.

Comparative efficacy of bisphosphonates in short-term fracture prevention for primary osteoporosis: a systematic review with network meta-analyses

Our network meta-analyses compared the efficacy of different bisphosphonates preventing fractures for primary osteoporosis. By including 36 studies, we found that zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture.

INTRODUCTION

This study was conducted in order to analyze the available evidence on the efficacy of bisphosphonates for preventing fractures.

METHODS

We considered randomized trials comparing any bisphosphonate with other bisphosphonate or placebo. We searched Cochrane Library, Embase, and PubMed and manually searched reference list of relevant articles. Pairwise and network meta-analyses were performed. The primary outcome is vertebral fracture. Secondary outcomes include nonvertebral fracture, hip fracture, wrist fracture, and any fracture.

RESULTS

Thirty-six studies were included. Significant difference was found between bisphosphonates for vertebral fracture and nonvertebral fracture (P < 0.0001 and P = 0.04, respectively). Compared with placebo, alendronate, clodronate, ibandronate, minodronate, pamidronate, risedronate, and zoledronic acid significantly prevented vertebral fracture. Zoledronic acid significantly reduced the risk of vertebral fracture, compared with alendronate, clodronate, etidronate, ibandronate, risedronate, and tiludronate (0.65 (0.46, 0.91), 0.53 (0.33, 0.86), 0.45 (0.27, 0.74), 0.52 (0.36, 0.75), 0.59 (0.42, 0.83), and 0.31 (0.21, 0.48), respectively). Compared with etidronate, clodronate and zoledronic acid significantly prevented nonvertebral fracture. Compared with alendronate, zoledronic acid significantly prevented any fracture. The possibility rankings showed that zoledronic ranked first in preventing vertebral fracture, hip fracture, and any fracture, and pamidronate ranked first in preventing nonvertebral fracture and wrist fracture. In the sensitivity analyses, zoledronic acid ranked first in preventing nonvertebral fracture, and alendronate ranked first in preventing hip fracture and wrist fracture.

CONCLUSION

Zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture. Uncertainty still remains and future studies are needed to accurately evaluate the comparative efficacy of bisphosphonates.

Targeting collagen for diagnostic imaging and therapeutic delivery

As the most abundant protein in mammals and a major structural component in extracellular matrix, collagen holds a pivotal role in tissue development and maintaining the homeostasis of our body. Persistent disruption to the balance between collagen production and degradation can cause a variety of diseases, some of which can be fatal. Collagen remodeling can lead to either an overproduction of collagen which can cause excessive collagen accumulation in organs, common to fibrosis, or uncontrolled degradation of collagen seen in degenerative diseases such as arthritis. Therefore, the ability to monitor the state of collagen is crucial for determining the presence and progression of numerous diseases. This review discusses the implications of collagen remodeling and its detection methods with specific focus on targeting native collagens as well as denatured collagens. It aims to help researchers understand the pathobiology of collagen-related diseases and create novel collagen targeting therapeutics and imaging modalities for biomedical applications.