Glucocorticoid-induced osteoporosis management among seniors, by year, sex, and indication, 1996-2012

Insights and implications of sexual dimorphism in osteoporosis

Osteoporosis, a metabolic bone disease characterized by low bone mineral density and deterioration of bone microarchitecture, has led to a high risk of fatal osteoporotic fractures worldwide. Accumulating evidence has revealed that sexual dimorphism is a notable feature of osteoporosis, with sex-specific differences in epidemiology and pathogenesis. Specifically, females are more susceptible than males to osteoporosis, while males are more prone to disability or death from the disease. To date, sex chromosome abnormalities and steroid hormones have been proven to contribute greatly to sexual dimorphism in osteoporosis by regulating the functions of bone cells. Understanding the sex-specific differences in osteoporosis and its related complications is essential for improving treatment strategies tailored to women and men. This literature review focuses on the mechanisms underlying sexual dimorphism in osteoporosis, mainly in a population of aging patients, chronic glucocorticoid administration, and diabetes. Moreover, we highlight the implications of sexual dimorphism for developing therapeutics and preventive strategies and screening approaches tailored to women and men. Additionally, the challenges in translating bench research to bedside treatments and future directions to overcome these obstacles will be discussed.

Guideline adherence by physicians for management of glucocorticoid-induced osteoporosis in Japan: a nationwide health insurance claims database study

Risk of fracture due to glucocorticoid-induced osteoporosis (GIO) can be reduced by anti-osteoporosis (OP) medications. The proportion of patients on long-term glucocorticoid therapy who received anti-OP medications according to the GIO management guidelines has increased in recent years, but is still suboptimal.

INTRODUCTION

Adherence of physicians to guidelines for glucocorticoid (GC)-induced osteoporosis (GIO) management is currently unclear. This study aimed to clarify the state of guideline adherence by physicians in Japan and identify factors associated with guideline adherence using a nationwide health insurance claims database (NDBJ).

METHODS

Patients aged ≥ 50 years who were prescribed GC for ≥ 90 days after 180 days without a GC prescription and who were followed up for osteoporosis (OP) management for the subsequent 360 days during the period spanning 2012-2018 were selected from the NDBJ. Guideline adherence was evaluated with the proportion of patients who received OP management as recommended by the Japanese guidelines. Information on previous vertebral and hip fractures, dementia, and polypharmacy was obtained. Factors associated with OP management were evaluated by logistic regression analysis.

RESULTS

A total of 512,296 patients were considered to be at high risk of fracture according to the guidelines. Proportions of patients receiving OP management (BMD testing or anti-OP medications) have increased in recent years. In 2017, 33.7% of men and 55.3% of women received OP management in the initial 90 days of GC therapy. Female sex, previous anti-OP medications, polypharmacy, and higher GC dose were significantly associated with receiving OP management, while dementia showed an inverse association. A prior history of hip fracture, a strong risk factor for future fracture, was not significantly associated with receiving OP management.

CONCLUSIONS

Although guideline adherence by physicians has increased in recent years, it remains suboptimal. Further efforts to improve guideline adherence are necessary.

TRIAL REGISTRATION NUMBER

The present study is not registered.

Status of Glucocorticoid-Induced Osteoporosis Preventive Care in Korea: A Retrospective Cohort Study on the Korean National Health Insurance Service Database

Background and Objectives: It is crucial to prevent osteoporosis in patients receiving long-term glucocorticoid (GC) treatment. This study aimed to investigate the frequency and associated factors of preventive care for glucocorticoid-induced osteoporosis (GIOP) in Korea. Materials and Methods: Using the Korean National Health Insurance Service database, we identified 37,133 individuals aged ≥ 20 years who commenced long-term (≥90 days) oral GC between 2011 and 2012. High-quality GIOP preventive care was defined as either a bone mineral density (BMD) test, calcium and/or vitamin D supplementation, or prescription osteoporosis medications within 6 months of GC initiation. Multivariable logistic regression models were used to calculate odds ratios (ORs) for associated factors for high-quality GIOP preventive care. Results: The mean age was 49.8 years, and 18,476 (49.8%) patients were female. The frequency of high-quality GIOP preventive care was only 3.68% (BMD test, 1.46%; osteoporosis medications, 1.65%; calcium/vitamin D, 1.63%). Increasing age (OR = 2.53, p < 0.001; 40–49 years, OR = 3.99, p < 0.001; 50–59 years, OR = 5.17, p < 0.001; 60–69 years, OR = 8.07, p < 0.001; ≥70 years, respectively), systemic autoimmune disease (OR = 3.08, p < 0.001), rural residence (OR = 1.19, p = 0.046), concomitant hyperthyroidism (OR = 1.58, p = 0.007), and malignancy (OR = 1.59, p < 0.001) were significantly associated with a higher likelihood of receiving high-quality GIOP preventive care. Male sex (OR = 0.26, p < 0.001) and GC prescription in primary care clinics and nursing hospitals (OR = 0.66, p < 0.001) were associated with a lower rate of high-quality GIOP preventive care. Conclusions: Most Korean patients treated with GC did not receive appropriate preventive care for GIOP in real-world practice. More efforts are needed by clinicians to prevent, screen, and treat GIOP.

Epidemiology of glucocorticoid-induced osteoporosis and management of associated fracture risk in Japan

INTRODUCTION

Glucocorticoid-induced osteoporosis (GIOP) is associated with a high fracture risk. Practice guidelines by the Japanese Society for Bone and Mineral Research in 2014 recommend bone densitometry and appropriate treatment to reduce this risk. The study objectives were to describe characteristics of GIOP patients in Japan and to evaluate their management in a subgroup of patients without comorbid cancer.

MATERIALS AND METHODS

This retrospective cohort study was performed using the Medical Data Vision (MDV) database from Japan. Adult patients initiating oral glucocorticoid treatment with a total GIOP risk score ≥ 3, based on the 2014 practice guideline, identified between 2009 and 2019 were eligible. A subgroup of patients without any cancer diagnosis was also identified. Data were extracted on demographics, concurrent medical conditions, use of bone densitometry, and osteoporosis treatment.

RESULTS

25,569 patients were eligible, of whom 12,227 had a confirmed cancer diagnosis. Mean age was 68.5 years and 12,356 patients (48.3%) were women. Concurrent medical conditions of interest were documented in 14,887 patients, most frequently rheumatoid arthritis (n = 4185) and asthma (n = 3085). Yearly bone densitometry was performed in 6.5% (n = 865) of the cancer-free subgroup; 51.8% (n = 6905) were prescribed an osteoporosis treatment, most frequently bisphosphonates (n = 5132; 74.3%). Between 2011 and 2018, rates of densitometry were stable, whereas prescription rates increased from 40.0 to 51.8%.

CONCLUSION

In spite of publication of guidelines for GIOP management, there is an important treatment gap in their application in everyday practice. For this reason, public health measures to increase physician awareness of GIOP are needed.

German Society of Rheumatology recommendations for management of glucocorticoid-induced osteoporosis

BACKGROUND

Glucocorticoids are of substantial therapeutic importance in the treatment of inflammatory diseases, but are also associated with bone mineral density loss, osteoporosis, and fractures, especially with long-term use.

OBJECTIVE

To develop recommendations for the management of glucocorticoid-induced osteoporosis (GIOP) in adult patients on long-term glucocorticoid (GC) treatment.

METHODS

A systematic literature search (SLR) was conducted to synthesize the evidence for GIOP prevention and treatment options. Recommendations were developed based on SLR/level of evidence and by previously defined questions and in a structured group consensus process.

RESULTS

Recommendations include supplementation with calcium and vitamin D under long-term GC therapy in adults. If specific osteologic treatment is indicated, we recommend bisphosphonates or denosumab as first-line treatment. If fracture risk is high, we recommend teriparatide as primary specific osteologic treatment. Denosumab should be used in cases of severe renal insufficiency, and specific osteologic treatment should not be given in pregnancy. For patients who have not reached the treatment goal, a switch to another class of specific osteologic drugs should be performed. We recommend re-evaluation after a treatment duration of 3-5 years or after termination of long-term GC treatment.

CONCLUSION

This work aims to provide evidence-based and consensus-based recommendations for the best possible management of GIOP in Germany and to support treatment decisions.

[German Society of Rheumatology Recommendations for the management of glucocorticoid-induced Osteoporosis. German version]

BACKGROUND

Glucocorticoids are of substantial therapeutic importance in the treatment of inflammatory diseases, but are also associated with bone mineral density loss, osteoporosis, and fractures, especially with long-term use.

OBJECTIVE

To develop recommendations for the management of glucocorticoid-induced osteoporosis (GIOP) in adult patients on long-term glucocorticoid (GC) treatment.

METHODS

A systematic literature search (SLR) was conducted to synthesize the evidence for GIOP prevention and treatment options. Recommendations were developed based on SLR/level of evidence and by previously defined questions and in a structured group consensus process.

RESULTS

Recommendations include supplementation with calcium and vitamin D under long-term GC therapy in adults. If specific osteologic treatment is indicated, we recommend bisphosphonates or denosumab as first-line treatment. If fracture risk is high, we recommend teriparatide as primary specific osteologic treatment. Denosumab should be used in cases of severe renal insufficiency, and specific osteologic treatment should not be given in pregnancy. For patients who have not reached the treatment goal, a switch to another class of specific osteologic drugs should be performed. We recommend re-evaluation after a treatment duration of 3-5 years or after termination of long-term GC treatment.

CONCLUSION

This work aims to provide evidence-based and consensus-based recommendations for the best possible management of GIOP in Germany and to support treatment decisions.

Guideline for the diagnosis, treatment and long-term management of cutaneous lupus erythematosus

Cutaneous lupus erythematosus (CLE) is an inflammatory, autoimmune disease encompassing a broad spectrum of subtypes including acute, subacute, chronic and intermittent CLE. Among these, chronic CLE can be further classified into several subclasses of lupus erythematosus (LE) such as discoid LE, verrucous LE, LE profundus, chilblain LE and Blaschko linear LE. To provide all dermatologists and rheumatologists with a practical guideline for the diagnosis, treatment and long-term management of CLE, this evidence- and consensus-based guideline was developed following the checklist established by the international Reporting Items for Practice Guidelines in Healthcare (RIGHT) Working Group and was registered at the International Practice Guideline Registry Platform. With the joint efforts of the Asian Dermatological Association (ADA), the Asian Academy of Dermatology and Venereology (AADV) and the Lupus Erythematosus Research Center of Chinese Society of Dermatology (CSD), a total of 25 dermatologists, 7 rheumatologists, one research scientist on lupus and 2 methodologists, from 16 countries/regions in Asia, America and Europe, participated in the development of this guideline. All recommendations were agreed on by at least 80% of the 32 voting physicians. As a consensus, diagnosis of CLE is mainly based on the evaluation of clinical and histopathological manifestations, with an exclusion of SLE by assessment of systemic involvement. For localized CLE lesions, topical corticosteroids and topical calcineurin inhibitors are first-line treatment. For widespread or severe CLE lesions and (or) cases resistant to topical treatment, systemic treatment including antimalarials and (or) short-term corticosteroids can be added. Notably, antimalarials are the first-line systemic treatment for all types of CLE, and can also be used in pregnant patients and pediatric patients. Second-line choices include thalidomide, retinoids, dapsone and MTX, whereas MMF is third-line treatment. Finally, pulsed-dye laser or surgery can be added as fourth-line treatment for localized, refractory lesions of CCLE in cosmetically unacceptable areas, whereas belimumab may be used as fourth-line treatment for widespread CLE lesions in patients with active SLE, or recurrence of ACLE during tapering of corticosteroids. As for management of the disease, patient education and a long-term follow-up are necessary. Disease activity, damage of skin and other organs, quality of life, comorbidities and possible adverse events are suggested to be assessed in every follow-up visit, when appropriate.

Understanding and Managing Corticosteroid-Induced Osteoporosis

Glucocorticoids are effective immunosuppressants used in a wide variety of diseases. Their use results in secondary osteoporosis in about 30–50% of chronic glucocorticoid users. Glucocorticoids cause a rapid decline in bone strength within the first 3–6 months mostly due to increased bone resorption by osteoclasts. This is followed by a more gradual loss of bone partly due to decreased osteoblastogenesis and osteoblast and osteocyte apoptosis. The loss of bone strength induced by glucocorticoids is not fully captured by bone mineral density measurements. Other tools such as the trabecular bone score and advanced imaging techniques give insight into bone quality; however, these are not used widely in clinical practice. Glucocorticoid-induced osteoporosis should be seen as a widely preventable disease. Currently, only about 15% of chronic glucocorticoid users are receiving optimal care. Glucocorticoids should be prescribed at the lowest dose and shortest duration. All patients should be counselled on lifestyle measures to maintain bone strength including nutrition and weight-bearing exercise. Pharmacological therapy should be considered for all patients at moderate to high risk of fracture as there is evidence for the prevention of bone loss and fractures with a favourable safety profile. Oral bisphosphonates are the current mainstay of therapy, whereas osteoanabolic agents may be considered for those at highest risk of fracture.

Over half of seniors who start oral bisphosphonate therapy are exposed for 3 or more years: novel rolling window approach and patterns of use

Most adherence studies only consider treatment following a first prescription. Using an extended follow-up, we found that 60% of seniors starting oral bisphosphonate therapy were exposed for ≥ 3 years (48% for ≥ 5 years). Studies are needed to examine the benefits and harms of continuing bisphosphonate therapy beyond 3 years.

INTRODUCTION

The purpose of this study was to identify and describe patterns of long-term oral bisphosphonate use among seniors using a novel methodological approach that considers extended follow-up.

METHODS

Among Ontarians aged 66 years or older, we identified subjects with a first dispensing of alendronate or risedronate between November 2000 and December 2016. We followed them until death or December 2019 to identify patients with ≥ 3 years of bisphosphonate use, defined as a proportion of days covered ≥ 80%, using 3-year rolling windows. We calculated the proportion of patients with long-term therapy (≥ 3 years of use) using Kaplan-Meier estimates. We described patterns of long-term use and compared patient characteristics between patients with and without long-term therapy.

RESULTS

We identified 260,784 eligible seniors initiating bisphosphonate therapy. Of these, 60% continued therapy ≥ 3 years (77% women), and 48% continued ≥ 5 years. Characteristics did not meaningfully differ between patients with or without long-term therapy. The median length of long-term therapy was 7.0 (IQR 5.1) years for women and 6.1 (IQR 4.3) years for men. Only 20% experienced a treatment gap before long-term therapy, yet 50% experienced a treatment gap of ≥ 120 days after a median 5.3 years of therapy. Eighty-one percent who returned to therapy following a treatment gap re-initiated an oral bisphosphonate, with 18% switching to denosumab.

CONCLUSIONS

Among seniors initiating oral bisphosphonates, we found that 60% receive at least 3 years of therapy when using an extended follow-up. Studies are needed to examine the benefits and harms of continuing bisphosphonate therapy beyond 3 years.

Betel leaf extract and its major component hydroxychavicol promote osteogenesis and alleviate glucocorticoid-induced osteoporosis in rats

Piper betle leaves possess several ethnomedicinal properties and are immensely used in traditional medicinal practices in regions of Asian and African subcontinents. However, their effects in treating skeletal complications are least known. In this study, we evaluated cellular and molecular effects of betel leaf extract (BLE) and its major phytoconstituent, hydroxychavicol (HCV) in promoting osteogenesis in vitro and alleviating glucocorticoid induced osteoporosis (GIO) in vivo. Both BLE and HCV markedly stimulated osteoblast differentiation of C3H10T1/2 cells with increased expression of RUNX2 and osteopontin through the GSK-3β/β-catenin-signaling pathway. Also, oral administration of BLE and HCV in GIO rats resulted in restoration of bone mass and tissue microarchitecture. Thus, with our findings we conclude that BLE and HCV promote osteogenesis of C3H10T1/2 cells via the GSK-3β/β-catenin pathway and alleviate GIO in rats.

When to Start and Stop Bone-Protecting Medication for Preventing Glucocorticoid-Induced Osteoporosis

Glucocorticoid-induced osteoporosis (GIOP) leads to fractures in up to 40% of patients with chronic glucocorticoid (GC) therapy when left untreated. GCs rapidly increase fracture risk, and thus many patients with anticipated chronic GC exposures should start anti-osteoporosis pharmacotherapy to prevent fractures. In addition to low awareness of the need for anti-osteoporosis therapy among clinicians treating patients with GCs, a major barrier to prevention of fractures from GIOP is a lack of clear guideline recommendations on when to start and stop anti-osteoporosis treatment in patients with GC use. The aim of this narrative review is to summarize current evidence and provide considerations for the duration of anti-osteoporosis treatment in patients taking GCs based on pre-clinical, clinical, epidemiologic, and pharmacologic evidence. We review the pathophysiology of GIOP, outline current guideline recommendations on initiating and stopping anti-osteoporosis therapy for GIOP, and present considerations for the duration of anti-osteoporosis treatment based on existing evidence. In each section, we illustrate major points through a patient case example. Finally, we conclude with proposed areas for future research and emerging areas of interest related to GIOP clinical management.

Glucocorticoid-induced osteoporosis: 2019 concise clinical review

Glucocorticoids remain widely used for many medical conditions, and fractures are the most serious common adverse event related to long-term glucocorticoid use. Glucocorticoid-induced osteoporosis (GIOP) develops in a time- and dose-dependent manner, but even at low doses, an increased risk of fragility fracture may be observed even within the first month of treatment. GIOP is mediated by multiple pathophysiologic mechanisms resulting in an inhibition of bone formation and an increase in bone resorption. The clinical assessment of GIOP has potential pitfalls since dual-energy X-ray absorptiometry (DXA) may underestimate the risk of fracture in patients treated with glucocorticoids. Many national organizations have developed guidelines for assessing fracture risk and treating patients with, or at risk for, GIOP. These groups advocate both antiresorptive agents and bone-forming agents based predominately on their efficacy in improving bone mineral density. Oral bisphosphonates are generally the first-line therapy for GIOP in most patients due to their proven efficacy, good safety, and low cost. For those patients at greater risk of fracture, teriparatide should be considered earlier, based on its ability to significantly reduce vertebral fractures when compared with alendronate. GIOP remains a major public health concern that is at least partially preventable with current and potential future therapeutic options.

Denosumab versus risedronate in glucocorticoid-induced osteoporosis: a multicentre, randomised, double-blind, active-controlled, double-dummy, non-inferiority study

BACKGROUND

Glucocorticoid-induced osteoporosis is the most common form of secondary osteoporosis and is associated with an estimated annual fracture rate of 5%. We aimed to assess the efficacy and safety of denosumab compared with risedronate in glucocorticoid-induced osteoporosis.

METHODS

We did a 24-month, double-blind, active-controlled, double-dummy, non-inferiority study at 79 centres in Europe, Latin America, Asia, and North America. Eligible patients were aged 18 years or older and were receiving glucocorticoids (≥7·5 mg prednisone daily, or equivalent) for at least 3 months (glucocorticoid continuing) or less than 3 months (glucocorticoid initiating) before screening. Patients younger than 50 years needed to have a history of osteoporosis-related fracture; glucocorticoid-continuing patients aged 50 years or older needed a lumbar spine, total hip, or femoral neck bone mineral density T score of -2·0 or less, or -1·0 or less if they had a history of osteoporosis-related fracture. Participants were randomly assigned (1:1) to either 60 mg subcutaneous denosumab every 6 months and oral placebo daily for 24 months, or 5 mg oral risedronate daily and subcutaneous placebo every 6 months for 24 months. Randomisation was stratified by sex within each subpopulation, and was done with an interactive voice-response system. Active drugs and corresponding placebos had identical packaging, labels, and appearance. The primary outcome was non-inferiority of denosumab to risedronate in terms of percentage change from baseline in lumbar spine bone mineral density at 12 months based on non-inferiority margins (-0·7 and -1·1 percentage points for the glucocorticoid-continuing and glucocorticoid-initiating subpopulations, respectively). Superiority was also assessed as a secondary outcome. The primary efficacy set included all randomly assigned participants who had a baseline and postbaseline lumbar spine bone mineral density measurement, and was analysed according to randomised treatment assignment. The safety analysis set included all randomly assigned participants who received at least one dose of investigational product, and was analysed by actual treatment received. This study is registered with ClinicalTrials.gov (NCT01575873) and is completed.

FINDINGS

Between March 28, 2012, and June 30, 2015, 795 patients, 505 of whom were glucocorticoid continuing and 290 of whom were glucocorticoid initiating, were enrolled and randomly assigned (398 to denosumab, 397 to risedronate). Denosumab was both non-inferior and superior to risedronate at 12 months for effect on bone mineral density at the lumbar spine in both glucocorticoid-continuing (4·4% [95% CI 3·8-5·0] vs 2·3% [1·7-2·9]; p<0·0001) and glucocorticoid-initiating (3·8% [3·1-4·5] vs 0·8% [0·2-1·5]; p<0·0001) subpopulations. Incidence of adverse events, serious adverse events (including infections), and fractures was similar between treatment groups. The most common adverse events were back pain (17 [4%] patients in the risedronate group and 18 [5%] in the denosumab group) and arthralgia (21 [5%] patients in the risedronate group and 17 [4%] in the denosumab group). Serious infection occurred in 15 (4%) patients in the risedronate group and 17 (4%) patients in the denosumab group.

INTERPRETATION

Denosumab could be a useful treatment option for patients newly initiating or continuing glucocorticoids who are at risk of fractures.

FUNDING

Amgen.

Effectiveness of Oral Bisphosphonates in Reducing Fracture Risk Among Oral Glucocorticoid Users: Three Matched Cohort Analyses

The benefit of oral bisphosphonates in reducing fracture risk in glucocorticoid-induced osteoporosis is controversial. We aimed to estimate the effectiveness of oral bisphosphonates in reducing fracture risk in a cohort of new chronic oral glucocorticoid users. We created three matched cohorts using health care administrative data from Ontario, Canada. We included residents aged 66 years and older initiating chronic oral glucocorticoids (≥450 mg prednisone equivalent and ≥2 glucocorticoid prescriptions within a 6-month window) between January 1998 and September 2014. Exposed patients were those who initiated an oral bisphosphonate (alendronate, etidronate, or risedronate) within the first 6 months of starting chronic oral glucocorticoid therapy. Exposed cohorts (3945 alendronate, 5825 risedronate, and 8464 etidronate) were each matched 1:1 to unexposed patients on glucocorticoid exposure, fracture risk factors, and propensity score. We examined incident hip (primary outcome), vertebral, forearm, and humerus fractures using Cox proportional hazard models. Alendronate (hazard ratio [HR] = 0.46, 95% confidence interval [CI] 0.25-0.80) and risedronate (HR = 0.58, 95% CI 0.36-0.90) were associated with reduced hip fracture risk. Alendronate (HR =  0.52, 95% CI 0.39-0.68), etidronate (HR = 0.59, 95% CI 0.48-0.73) and risedronate (HR = 0.47 95% CI 0.36-0.60) were associated with reduced vertebral fracture risk. No risk reduction in forearm or humerus fractures was apparent for any bisphosphonate. Among older chronic glucocorticoid initiators, all oral bisphosphonates reduced vertebral fracture risk, yet only alendronate and risedronate reduced hip fracture risk. Results were similar between men and women. We provided compelling evidence that early initiation of oral bisphosphonates during chronic oral glucocorticoid therapy is beneficial to prevent osteoporotic fractures. © 2017 American Society for Bone and Mineral Research.

The CRH-Transgenic Cushingoid Mouse Is a Model of Glucocorticoid-Induced Osteoporosis

Glucocorticoids (GCs) have unparalleled anti‐inflammatory and immunosuppressive properties, which accounts for their widespread prescription and use. Unfortunately, a limitation to GC therapy is a wide range of negative side effects including Cushing's syndrome, a disease characterized by metabolic abnormalities including muscle wasting and osteoporosis. GC‐induced osteoporosis occurs in 30% to 50% of patients on GC therapy and thus, represents an important area of study. Herein, we characterize the molecular and physiologic effects of GC‐induced osteoporosis using the Cushing's mouse model, the corticotropin releasing hormone (CRH) transgenic mouse (CRH‐Tg). The humeri, femurs, and tibias from wild‐type (WT) and CRH‐Tg male mice, aged 13 to 14 weeks old were subjected to multiple bone tests including, micro–computed tomography (μCT), static and dynamic histomorphometry, strength testing, and gene expression analyses. The CRH‐Tg mice had a 38% decrease in cortical bone area, a 35% decrease in cortical thickness, a 16% decrease in trabecular thickness, a sixfold increase in bone adiposity, a 27% reduction in osteoid width, a 75% increase in bone‐resorbing osteoclast number/bone surface, a 34% decrease in bone formation rate, and a 40% decrease in bone strength compared to WT mice. At the gene expression level, CRH‐Tg bone showed significantly increased osteoclast markers and decreased osteoblast markers, whereas CRH‐Tg muscle had increased muscle atrophy gene markers compared to WT mice. Overall, the CRH‐Tg mouse model aged to 14 weeks recapitulated many features of osteoporosis in Cushing's syndrome and thus, represents a useful model to study GC‐induced osteoporosis and interventions that target the effects of GCs on the skeleton. © 2017 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

Fracture risk in oral glucocorticoid users: a Bayesian meta-regression leveraging control arms of osteoporosis clinical trials

Little data exist on the frequency of fracture among oral glucocorticoid users. We examined the effect of oral glucocorticoids on fracture incidence using data from randomized controlled trials. Patients starting glucocorticoids had a higher probability of fracture and decline in bone mineral density compared to chronic glucocorticoid users.

INTRODUCTION

Oral glucocorticoids (GCs) are the leading cause of secondary osteoporosis. However, there have been few studies that quantify the rate of fracture among GC users. We sought to provide a pooled estimate of fracture risk from randomized controlled trials (RCTs) of GC-treated patients.

METHODS

We updated a MEDLINE search published by the American College of Rheumatology through to March 2015 and identified RCTs of osteoporosis therapies that reported fracture and bone mineral density (BMD) among oral GC users. We restricted the analysis to placebo or control arms. RCT arms were stratified by GC exposure at enrolment to GC initiators (≤6 months) and chronic GC users (>6 months). Bayesian meta-regression was used to estimate the annual probability of vertebral fracture (primary), non-vertebral fracture and percentage change in lumbar spine and femoral neck BMD.

RESULTS

The annual incidence of vertebral and non-vertebral fracture was 5.1 % (95 % CrI = 2.8-8.2) and 2.5 % (95 % CrI = 1.2--4.2) among GC initiators, and 3.2 % (95 % CrI = 1.8-5.0) and 3.0 % (95 % CrI = 0.8-5.9) among chronic GC users. Our meta-regression identified a non-significant effect of group-level variables (mean age, mean BMD, mean GC daily dose, patients with previous vertebral fractures, proportion of women and adjuvant used) on vertebral fracture rate.

CONCLUSION

Our study found higher vertebral fracture incidence among GC initiators, yet a relative decline in fracture incidence with longer exposure. Our findings suggest that fracture incidence among oral GC users may be more common than previously estimated. Optimizing GC-induced osteoporosis management during early exposure to GC is essential to prevent fractures.

Curcumin alleviates glucocorticoid-induced osteoporosis through the regulation of the Wnt signaling pathway

It is known that prolonged glucocorticoid (GC) treatment results in osteoporosis. This study aimed to evaluate the protective effects of curcumin on the bones of rats with dexamethasone (DXM)-induced osteoporosis. In the present study, rats were administered DXM for 60 days to induce osteoporosis, and they were then treated with curcumin (100 mg/kg/day) for a further 60 days. H&E staining was used to observe the pathological changes in the femurs. Serum osteocalcin levels and collagen-type I fragments (CTX) were examined as bone metabolism markers. The results revealed that treatment with curcumin attenuated DXM-induced bone injury in femurs, increased the serum levels of osteocalcin and decreased the levels of CTX. In addition, in in vitro experiments, primary rat osteoblasts treated with curcumin at 0.5, 1 and 2 µM were exposed to 100 nM DXM. An MTT assay was used to determine the proliferative ability of the cells. Alkaline phosphatase activity, and the mRNA expression levels of runt-related transcription factor 2 (Runx2), osterix, osteocalcin, collagen, type 1, alpha 1 (Col1A1) and osteonectin were detected to assess transcription factor-associated osteogenic differentiation. The mRNA and protein expression levels of osteoprotegerin (OPG) and receptor activator for nuclear factor-kappa B ligand (RANKL) were detected to assess cytokine-associated osteoclastogenesis. The results demonstrated that curcumin prevented the DXM-induced inhibition of the proliferative ability of the osteoblasts in a dose-dependent manner. In addition, curcumin upregulated the mRNA expression levels of transcription factors that favor osteoblast differentiation and increased the ratio of OPG to RANKL. Moreover, the effects of curcumin on the Wnt signaling pathway were also investigated. RT-qPCR and western blot analysis demonstrated that the Wnt signaling pathway, which was inhibited by DXM, was re-activated upon treatment with curcumin. Immunofluorescence staining revealed that curcumin restored the intranuclear staining of β-catenin in the DXM-stimulated osteoblasts. Collectively, our data demonstrate that curcumin may be a potential therapeutic agent for the treatment of GC-induced osteoporosis.