Asia-Pacific consensus on long-term and sequential therapy for osteoporosis.

Objectives: This study aimed to present the Asia-Pacific consensus on long-term and sequential therapy for osteoporosis, offering evidence-based recommendations for the effective management of this chronic condition. The primary focus is on achieving optimal fracture prevention through a comprehensive, individualized approach. Methods: A panel of experts convened to develop consensus statements by synthesizing the current literature and leveraging clinical expertise. The review encompassed long-term anti-osteoporosis medication goals, first-line treatments for individuals at very high fracture risk, and the strategic integration of anabolic and antiresorptive agents in sequential therapy approaches. Results: The panelists reached a consensus on 12 statements. Key recommendations included advocating for anabolic agents as the first-line treatment for individuals at very high fracture risk and transitioning to antiresorptive agents following the completion of anabolic therapy. Anabolic therapy remains an option for individuals experiencing new fractures or persistent high fracture risk despite antiresorptive treatment. In cases of inadequate response, the consensus recommended considering a switch to more potent medications. The consensus also addressed the management of medication-related complications, proposing alternatives instead of discontinuation of treatment. Conclusions: This consensus provides a comprehensive, cost-effective strategy for fracture prevention with an emphasis on shared decision-making and the incorporation of country-specific case management systems, such as fracture liaison services. It serves as a valuable guide for healthcare professionals in the Asia-Pacific region, contributing to the ongoing evolution of osteoporosis management.

Survey of awareness and attitudes to the management of fragility fractures among the membership of the Asia Pacific Orthopaedic Association.

A survey of awareness and attitudes to the management of fragility fractures among the membership of the Asia Pacific Orthopaedic Association conducted in 2022 found considerable variation in care across the region. A Call to Action is proposed to improve acute care, rehabilitation and secondary fracture prevention across Asia Pacific. PURPOSE: Fragility fractures impose a substantial burden on older people and their families, healthcare systems and national economies. The current incidence of hip and other fragility fractures across the Asia Pacific region is enormous and set to escalate rapidly in the coming decades. This publication describes findings of a survey of awareness and attitudes to the management of fragility fractures among the membership of the Asia Pacific Orthopaedic Association (APOA) conducted in 2022. METHODS: The survey was developed as a collaboration between the Asia Pacific Osteoporosis and Fragility Fracture Society and the Asia Pacific Fragility Fracture Alliance, and included questions relating to aspects of care upon presentation, during surgery and mobilisation, secondary fracture prevention, and access to specific services. RESULTS: In total, 521 APOA members completed the survey and marked variation in delivery of care was evident. Notable findings included: Fifty-nine percent of respondents indicated that analgesia was routinely initiated in transit (by paramedics) or within 30 minutes of arrival in the Emergency Department. One-quarter of respondents stated that more than 80% of their patients underwent surgery within 48 hours of admission. One-third of respondents considered non-hip, non-vertebral fractures to merit assessment of future fracture risk. One-third of respondents reported the presence of an Orthogeriatric Service in their hospital, and less than a quarter reported the presence of a Fracture Liaison Service. CONCLUSION: A Call to Action for all National Orthopaedic Associations affiliated with APOA is proposed to improve the care of fragility fracture patients across the region.

Sequential multimodal treatments with chemotherapy and surgery for advanced soft tissue sarcoma may be associated with better survival than chemotherapy.

BACKGROUND: In patients with advanced soft tissue sarcoma (STS), surgery had been reported to be associated with superior overall survival (OS). Chemotherapy details for such patients were less reported, and whether multimodal treatment with surgery and chemotherapy provides extra survival benefit remains unclear. METHODS: We retrospectively reviewed patients with newly diagnosed advanced STS treated at National Taiwan University Hospital from January 1, 2011, to December 31, 2017. OS was calculated from the day of diagnosis of advanced STS to the day of death or last follow-up. Baseline patient characteristics and details regarding surgery and chemotherapy were recorded. RESULTS: A total of 545 patients were diagnosed with STS from 2011 to 2017, of which 226 patients had advanced STS. The median age was 54.7 years, and 54% of patients were women. Approximately 38% of patients with advanced STS underwent surgery and exhibited a trend of longer OS compared with who did not (median = 18.6 vs. 11.9 months, p = 0.083). In the chemotherapy subgroup, the benefit of surgery was more prominent (median = 21.9 vs. 16.5 months, p = 0.037). Patients who received chemotherapy prior to surgery exhibited numerically longer OS than those who underwent surgery first (median = 33.9 vs. 18.3 months, p = 0.155). After adjusting other clinical factors, chemotherapy remained an independent factor associated with favourable OS. CONCLUSION: Surgery may be more beneficial for the patients who receive chemotherapy. Our results support evaluation of sequential multimodal treatments strategy including surgery and chemotherapy in patients with advanced STS.

Nε-(1-Carboxymethyl)-L-lysine/RAGE Signaling Drives Metastasis and Cancer Stemness through ERK/NFκB axis in Osteosarcoma.

Osteosarcoma is an extremely aggressive bone cancer with poor prognosis. Nε-(1-Carboxymethyl)-L-lysine (CML), an advanced glycation end product (AGE), can link to cancer progression, tumorigenesis and metastasis, although the underlying mechanism remains unclear. The role of CML in osteosarcoma progression is still unclear. We hypothesized that CML could promote migration, invasion, and stemness in osteosarcoma cells. CML and its receptor (RAGE; receptor for AGE) were higher expressed at advanced stages in human osteosarcoma tissues. In mouse models, which streptozotocin was administered to induce CML accumulation in the body, the subcutaneous tumor growth was not affected, but the tumor metastasis using tail vein injection model was enhanced. In cell models (MG63 and U2OS cells), CML enhanced tumor sphere formation and acquisition of cancer stem cell characteristics, induced migration and invasion abilities, as well as triggered the epithelial-mesenchymal transition process, which were associated with RAGE expression and activation of downstream signaling pathways, especially the ERK/NFκB pathway. RAGE inhibition elicited CML-induced cell migration, invasion, and stemness through RAGE-mediated ERK/NFκB pathway. These results revealed a crucial role for CML in driving stemness and metastasis in osteosarcoma. These findings uncover a potential CML/RAGE connection and mechanism to osteosarcoma progression and set the stage for further investigation.

Osteoporosis care after hip fracture: Observation from national health insurance database and fracture liaison services.

BACKGROUND: The objective of this research was to report the trend of osteoporosis care after hip fractures from usual care (UC) and to compare the quality of care with those who received fracture liaison services (FLSs). METHODS: Data on osteoporosis care for patients with hip fracture were acquired from the National Health Insurance claims (UC group), and surveys from FLS programs (FLS group). A total of 183,300 patients receiving UC and 3010 patients receiving FLS were studied. For the two groups, common osteoporosis care indicators, such as bone mineral density (BMD) testing rate, antiosteoporosis medication commencement rate, and adherence rate were described. RESULTS: There were 2488 participants (82.7%) in the FLS group who completed Dual-energy X-ray absorptiometry (DXA) in 8 weeks, 155 (5.1%) who finished it between 8 weeks and 1 year. Even in 2018, when the DXA completion rate was at its highest, the completion rate in the UC group was only 23.5%. In terms of medication commencement, 2372 FLS patients (78.8%) received treatment within 3 months. Only 24.9% of the UC patients received antiosteoporosis medication within 3 months. Furthermore, antiosteoporosis medication adherence rate was 92.2% after 1 year and 83.9% after 2 years in the FLS group, but these were only 66.5% and 42.7%, respectively, in the UC group. CONCLUSION: Patients who received FLS had more timely BMD exams, antiosteoporosis medication treatment, and higher adherence to antiosteoporosis therapy than those who received UC. The discrepancy in rates of continuing treatment became more significant over time between both groups.

Eleven years secular trend of the initiation of anti-osteoporosis medications and subsequent fractures in Taiwan: From 2008 to 2018.

BACKGROUND: Osteoporosis is a common metabolic bone disease that benefits from many newly developed anti-osteoporosis medications (AOMs). Reimbursement policies need to allocate medical budgets properly based on evidence-based data. This study aimed to investigate the 11-year secular trend, focusing on older age and males in this adjustment wave of the National Health Insurance reimbursement. METHODS: We adopted a nationwide cohort from Taiwan's National Health Insurance Research Database (NHIRD). Patients undergoing newly initiated AOMs from 2008 to 2018 were included. The AOMs in this study included denosumab, zoledronate, ibandronate, alendronate, raloxifene, and risedronate. Patients <50 years, pathological fractures, missing data, and two AOMs prescribed were excluded. The real-world trends related to subsequent fragility fracture and death within 1 and 3 years were used to evaluate the potential effects due to revision of reimbursement policies. RESULTS: Of 393,092 patients, among them, 336,229 patients met the criteria, whose mean age ranged from 73.3 to 74.4 years, and nearly 80% were female. Further analysis showed a steady increase of AOMs from 5567 (17.1%) and 8802 (27.0%) in 2008-6697 (18.3%) and 10,793 (29.5%) in 2018 for males and 80+ years respectively. The subsequent fragility fracture within one and three years post AOMs initiation was 5.81% and 11.80% in 2018. CONCLUSION: This study showed an immediate drop in AOMs prescription after the implementation of a new stricter reimbursement policy. It took 5 years to return the annual prescription number.

Constraining in reimbursement criteria and the adherence to anti-osteoporosis medications (AOMs) in Taiwan: Urbanization makes the difference.

BACKGROUND: The Bureau of National Health Insurance in Taiwan implemented a new reimbursement scheme incorporating bone mineral density (BMD) criteria on Jan. 1, 2011. This study aimed to investigate a real-life 11-year secular trend of adherence in new AOMs users and evaluated the change of adherence to AOMs therapy in different urbanization areas after reimbursement criteria were restrained. METHODS: We used Taiwan's National Health Insurance Research Database to identify new AOMs users as our study population. The AOMs in this study included denosumab, zoledronate, ibandronate, alendronate, raloxifene, and risedronate. The first prescription date of AOMs was defined as the cohort entry date. The adherence rates within one year after initiation were assessed. RESULTS: High adherence (≥75%) in the first year increased markedly after the new reimbursement scheme in 2011, changing from 31.8% in 2008, and 41.7% in 2011 to 54.2% in 2018. On the other hand, low adherence (<25%) decreased from 38.8% in 2008 to 14.6% in 2018. In addition, the switchers increased from 5.9% in 2008 to 9.3% in 2018, indicating a more flexible choice of AOMs. The proportion of high adherence to AOMs was highest in high-urbanization areas, and the proportion increased about two times from 30% in 2008 to 60% in 2018. CONCLUSION: The implementation of new reimbursement criteria in 2011 was associated with increased adherence to AOMs and the increase was most apparent in high-urbanization areas.

Does the Presence of Missing Data Affect the Performance of the SORG Machine-learning Algorithm for Patients With Spinal Metastasis? Development of an Internet Application Algorithm.

BACKGROUND: The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA) was developed to predict the survival of patients with spinal metastasis. The algorithm was successfully tested in five international institutions using 1101 patients from different continents. The incorporation of 18 prognostic factors strengthens its predictive ability but limits its clinical utility because some prognostic factors might not be clinically available when a clinician wishes to make a prediction. QUESTIONS/PURPOSES: We performed this study to (1) evaluate the SORG-MLA's performance with data and (2) develop an internet-based application to impute the missing data. METHODS: A total of 2768 patients were included in this study. The data of 617 patients who were treated surgically were intentionally erased, and the data of the other 2151 patients who were treated with radiotherapy and medical treatment were used to impute the artificially missing data. Compared with those who were treated nonsurgically, patients undergoing surgery were younger (median 59 years [IQR 51 to 67 years] versus median 62 years [IQR 53 to 71 years]) and had a higher proportion of patients with at least three spinal metastatic levels (77% [474 of 617] versus 72% [1547 of 2151]), more neurologic deficit (normal American Spinal Injury Association [E] 68% [301 of 443] versus 79% [1227 of 1561]), higher BMI (23 kg/m2 [IQR 20 to 25 kg/m2] versus 22 kg/m2 [IQR 20 to 25 kg/m2]), higher platelet count (240 × 103/µL [IQR 173 to 327 × 103/µL] versus 227 × 103/µL [IQR 165 to 302 × 103/µL], higher lymphocyte count (15 × 103/µL [IQR 9 to 21× 103/µL] versus 14 × 103/µL [IQR 8 to 21 × 103/µL]), lower serum creatinine level (0.7 mg/dL [IQR 0.6 to 0.9 mg/dL] versus 0.8 mg/dL [IQR 0.6 to 1.0 mg/dL]), less previous systemic therapy (19% [115 of 617] versus 24% [526 of 2151]), fewer Charlson comorbidities other than cancer (28% [170 of 617] versus 36% [770 of 2151]), and longer median survival. The two patient groups did not differ in other regards. These findings aligned with our institutional philosophy of selecting patients for surgical intervention based on their level of favorable prognostic factors such as BMI or lymphocyte counts and lower levels of unfavorable prognostic factors such as white blood cell counts or serum creatinine level, as well as the degree of spinal instability and severity of neurologic deficits. This approach aims to identify patients with better survival outcomes and prioritize their surgical intervention accordingly. Seven factors (serum albumin and alkaline phosphatase levels, international normalized ratio, lymphocyte and neutrophil counts, and the presence of visceral or brain metastases) were considered possible missing items based on five previous validation studies and clinical experience. Artificially missing data were imputed using the missForest imputation technique, which was previously applied and successfully tested to fit the SORG-MLA in validation studies. Discrimination, calibration, overall performance, and decision curve analysis were applied to evaluate the SORG-MLA's performance. The discrimination ability was measured with an area under the receiver operating characteristic curve. It ranges from 0.5 to 1.0, with 0.5 indicating the worst discrimination and 1.0 indicating perfect discrimination. An area under the curve of 0.7 is considered clinically acceptable discrimination. Calibration refers to the agreement between the predicted outcomes and actual outcomes. An ideal calibration model will yield predicted survival rates that are congruent with the observed survival rates. The Brier score measures the squared difference between the actual outcome and predicted probability, which captures calibration and discrimination ability simultaneously. A Brier score of 0 indicates perfect prediction, whereas a Brier score of 1 indicates the poorest prediction. A decision curve analysis was performed for the 6-week, 90-day, and 1-year prediction models to evaluate their net benefit across different threshold probabilities. Using the results from our analysis, we developed an internet-based application that facilitates real-time data imputation for clinical decision-making at the point of care. This tool allows healthcare professionals to efficiently and effectively address missing data, ensuring that patient care remains optimal at all times. RESULTS: Generally, the SORG-MLA demonstrated good discriminatory ability, with areas under the curve greater than 0.7 in most cases, and good overall performance, with up to 25% improvement in Brier scores in the presence of one to three missing items. The only exceptions were albumin level and lymphocyte count, because the SORG-MLA's performance was reduced when these two items were missing, indicating that the SORG-MLA might be unreliable without these values. The model tended to underestimate the patient survival rate. As the number of missing items increased, the model's discriminatory ability was progressively impaired, and a marked underestimation of patient survival rates was observed. Specifically, when three items were missing, the number of actual survivors was up to 1.3 times greater than the number of expected survivors, while only 10% discrepancy was observed when only one item was missing. When either two or three items were omitted, the decision curves exhibited substantial overlap, indicating a lack of consistent disparities in performance. This finding suggests that the SORG-MLA consistently generates accurate predictions, regardless of the two or three items that are omitted. We developed an internet application (https://sorg-spine-mets-missing-data-imputation.azurewebsites.net/) that allows the use of SORG-MLA with up to three missing items. CONCLUSION: The SORG-MLA generally performed well in the presence of one to three missing items, except for serum albumin level and lymphocyte count (which are essential for adequate predictions, even using our modified version of the SORG-MLA). We recommend that future studies should develop prediction models that allow for their use when there are missing data, or provide a means to impute those missing data, because some data are not available at the time a clinical decision must be made. CLINICAL RELEVANCE: The results suggested the algorithm could be helpful when a radiologic evaluation owing to a lengthy waiting period cannot be performed in time, especially in situations when an early operation could be beneficial. It could help orthopaedic surgeons to decide whether to intervene palliatively or extensively, even when the surgical indication is clear.

Comparison of eight modern preoperative scoring systems for survival prediction in patients with extremity metastasis.

BACKGROUND: Survival is an important factor to consider when clinicians make treatment decisions for patients with skeletal metastasis. Several preoperative scoring systems (PSSs) have been developed to aid in survival prediction. Although we previously validated the Skeletal Oncology Research Group Machine-learning Algorithm (SORG-MLA) in Taiwanese patients of Han Chinese descent, the performance of other existing PSSs remains largely unknown outside their respective development cohorts. We aim to determine which PSS performs best in this unique population and provide a direct comparison between these models. METHODS: We retrospectively included 356 patients undergoing surgical treatment for extremity metastasis at a tertiary center in Taiwan to validate and compare eight PSSs. Discrimination (c-index), decision curve (DCA), calibration (ratio of observed:expected survivors), and overall performance (Brier score) analyses were conducted to evaluate these models' performance in our cohort. RESULTS: The discriminatory ability of all PSSs declined in our Taiwanese cohort compared with their Western validations. SORG-MLA is the only PSS that still demonstrated excellent discrimination (c-indexes>0.8) in our patients. SORG-MLA also brought the most net benefit across a wide range of risk probabilities on DCA with its 3-month and 12-month survival predictions. CONCLUSIONS: Clinicians should consider potential ethnogeographic variations of a PSS's performance when applying it onto their specific patient populations. Further international validation studies are needed to ensure that existing PSSs are generalizable and can be integrated into the shared treatment decision-making process. As cancer treatment keeps advancing, researchers developing a new prediction model or refining an existing one could potentially improve their algorithm's performance by using data gathered from more recent patients that are reflective of the current state of cancer care.

Nε-(1-Carboxymethyl)-L-lysine, an advanced glycation end product, exerts malignancy on chondrosarcoma via the activation of cancer stemness.

Despite epidemiological evidence that suggests diabetes mellitus is a risk factor for cancer, the link between diabetes mellitus and primary bone cancer is rarely discussed. Chondrosarcomas are primary malignant cartilage tumors with poor prognosis and high metastatic potential. It remains unclear whether hyperglycemia affects the stemness and malignancy of chondrosarcoma cells. Nε-(1-Carboxymethyl)-L-lysine (CML), an advanced glycation end product (AGE), is a major immunological epitope detected in the tissue proteins of diabetic patients. We hypothesized that CML could enhance cancer stemness in chondrosarcoma cells. CML enhanced tumor-sphere formation and the expression of cancer stem cell markers in human chondrosarcoma cell lines. Migration and invasion ability and the epithelial-mesenchymal transition (EMT) process were also induced by CML treatment. Moreover, CML increased the protein expression levels of the receptor for AGE (RAGE), phosphorylated NFκB-p65, and decreased the phosphorylation of AKT and GSK-3. We also found that hyperglycemia with high CML levels facilitated tumor metastasis, whereas tumor growth was not affected in the streptozotocin (STZ)-induced diabetic NOD/SCID tumor xenograft mouse models. Our results indicate that CML enhances chondrosarcoma stemness and metastasis, which may reveal the relationship between AGE and bone cancer metastasis.

The real-world adherence of the first-line anti-osteoporosis medications in Taiwan: Visualize the gap between reality and expectations.

BACKGROUND: Adherence to anti-osteoporosis medications (AOMs) is crucial. National Health Insurance (NHI) in Taiwan has its own rules of reimbursement rule for AOMs. The midterm adherence remained inconclusive. Here we investigated the adherence according to the initially used AOMs, for three consecutive years. METHODS: The nationwide cohort study from 2008 to 2018, based on Taiwan's National Health Insurance Research Database, included 336,229 patients. Their adherence, indicated by medication possession ratio (MPR), to the initial AOMs was investigated yearly for three consecutive years. The overall MPRs (OMPR), including the switched AOMs, were also calculated in the first year. The Sankey diagram further visualized the patient flows toward different adherence according to the initial AOMs. RESULTS: The OMPR in the first year improved if the patients used AOMs with longer dosing intervals. 100%, 68.9%, 40.7%, and 34.0% of the patients started the treatment with zoledronate, denosumab, alendronate, and raloxifene, respectively, had OMPR ≥75% in the first year. In the 3rd year, only 20.89%, 24.13%, and 12.83% of the patients continuously treated with zoledronate, denosumab, and alendronate, respectively, had MPR ≥75%. From the Sankey diagram, we also observed that patients who had poor adherence at one year were inclined to have poor adherence or discontinue antiosteoporosis treatment in the next year. CONCLUSION: The initial AOMs and the observed adherence may provide clues for optimizing patient treatment. The real-world adherence in Taiwan was far from satisfactory in our study.

Diagnostic accuracy of algorithms to define incident and second hip fractures: A Taiwan validation study.

BACKGROUND: Previous epidemiological researchers have used various algorithms to identify a second hip fracture; however, there has been no validation of these algorithms to date. This study aimed to verify existing algorithms for identifying second hip fracture under the International Classification of Diseases diagnostic coding systems. Furthermore, we examined the validity of two newly proposed algorithms that integrated the concept of periprosthetic fractures and laterality of the ICD-10 coding system. METHODS: Claims data of patients hospitalized for hip fracture from National Taiwan University Hospitals between 2007 and 2020 were retrieved. Hip fracture was confirmed by 2 orthopaedic surgeons with medical records and imaging data as gold standards. The validity of 9 existing and 2 newly proposed algorithms for identifying second hip fracture was evaluated. RESULTS: The positive predictive value (PPV) range between 84% and 90% in existing algorithms for identifying second hip fractures. Noteworthy, the longer time interval for discrimination resulted in slightly increased PPV (from 87% to 90%), while decreased sensitivity noticeably (from 87% to 72%). When considering the information about periprosthetic fracture, the PPV increased to 91% without diminished sensitivity. The PPV of the newly proposed ICD-10-specific algorithm was 100%. CONCLUSION: Algorithms integrated clinical insights of periprosthetic fractures and laterality concept of ICD-10 coding system provided satisfactory validity and help precisely define second hip fracture in future database research.

Asia-pacific consensus on osteoporotic fracture prevention in postmenopausal women with low bone mass or osteoporosis but no fragility fractures.

Postmenopausal women are at significant risk for osteoporotic fractures due to their rapid bone loss. Half of all postmenopausal women will get an osteoporosis-related fracture over their lifetime, with 25% developing a spine deformity and 15% developing a hip fracture. By 2050, more than half of all osteoporotic fractures will occur in Asia, with postmenopausal women being the most susceptible. Early management can halt or even reverse the progression of osteoporosis. Consequently, on October 31, 2020, the Taiwanese Osteoporosis Association hosted the Asia-Pacific (AP) Postmenopausal Osteoporotic Fracture Prevention (POFP) consensus meeting, which was supported by the Asian Federation of Osteoporosis Societies (AFOS) and the Asia Pacific Osteoporosis Foundation (APOF). International and domestic experts developed ten applicable statements for the prevention of osteoporotic fractures in postmenopausal women with low bone mass or osteoporosis but no fragility fractures in the AP region. The experts advocated, for example, that postmenopausal women with a high fracture risk be reimbursed for pharmaceutical therapy to prevent osteoporotic fractures. More clinical experience and data are required to modify intervention tactics.

Clinical practice guidelines for the prevention and treatment of osteoporosis in Taiwan: 2022 update.

Osteoporosis greatly increases the risk of fractures. Osteoporotic fractures negatively impact quality of life, increase the burden of care, and increase mortality. Taiwan is an area with a high prevalence of osteoporosis. This updated summary of guidelines has been developed by experts of the Taiwan Osteoporosis Association with the intention of reducing the risks of osteoporotic fractures and improving the quality of care for patients with osteoporosis. The updated guidelines compile the latest evidence to provide clinicians and other healthcare professionals with practical recommendations for the prevention, diagnosis, and management of osteoporosis under clinical settings in Taiwan.

Urban-rural differences in outcomes and management of vertebral fractures: A real-world observational study.

BACKGROUND: A fracture liaison services (FLSs) and its modified services reduce refractures and mortality and can be cost-effective. Limited studies have addressed whether urban-rural differences exist in vertebral fracture outcomes and management. Therefore, the aims of the study were to investigate any urban-rural differences in refracture, mortality, prescription pattern, and associated factors of vertebral fractures after receiving assistance from an FLSs. METHODS: Baseline characteristics and osteoporosis medication prescription patterns of participants were collected. After 1-year follow-up, mortality, refracture rate, and osteoporosis medication switching and adherence were evaluated. Multivariate logistic regressions were performed to identify baseline correlates on one-year mortality. RESULTS: There was higher mortality rate in the rural group but no urban-rural difference in the 1-year refracture rate after implementation of FLSs and medication management services (MMSs). The types of osteoporosis medications prescribed for both groups were similar, but participants in the rural group were less likely to change their osteoporosis medications during the 1-year follow-up timeframe and with lower adherence rate. The likelihood of being older and having chronic kidney disease, osteoarthritis, and neurological disease was higher in the rural group. CONCLUSION: Our multicomponent services have similar effectiveness in osteoporosis treatment between urban and rural areas. The overall adherence rate was lower in the rural group with higher mortality but no difference in the refracture rate in one year.

A ubiquitous endocrine disruptor tributyltin induces muscle wasting and retards muscle regeneration.

BACKGROUND: Organotin pollutant tributyltin (TBT) is an environmental endocrine disrupting chemical and is a known obesogen and diabetogen. TBT can be detected in human following consumption of contaminated seafood or water. The decrease in muscle strength and quality has been shown to be associated with type 2 diabetes in older adults. However, the adverse effects of TBT on the muscle mass and function still remain unclear. Here, we investigated the effects and molecule mechanisms of low-dose TBT on skeletal muscle regeneration and atrophy/wasting using the cultured skeletal muscle cell and adult mouse models. METHODS: The mouse myoblasts (C2C12) and differentiated myotubes were used to assess the in vitro effects of low-dose tributyltin (0.01-0.5 µM). The in vivo effects of TBT at the doses of 5 and 25 µg/kg/day (n = 6/group), which were five times lower than the established no observed adverse effect level (NOAEL) and equal to NOAEL, respectively, by oral administration for 4 weeks on muscle wasting and muscle regeneration were evaluated in a mouse model with or without glycerol-induced muscle injury/regeneration. RESULTS: TBT reduced myogenic differentiation in myoblasts (myotube with 6-10 nuclei: 53.9 and 35.8% control for 0.05 and 0.1 µM, respectively, n = 4, P < 0.05). TBT also decreased myotube diameter, upregulated protein expression levels of muscle-specific ubiquitin ligases (Atrogin-1 and MuRF1), myostatin, phosphorylated AMPKα, and phosphorylated NFκB-p65, and downregulated protein expression levels of phosphorylated AKT and phosphorylated FoxO1 in myotubes (0.2 and 0.5 µM, n = 6, P < 0.05). Exposure of TBT in mice elevated body weight, decreased muscle mass, and induced muscular dysfunction (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). TBT inhibited soleus muscle regeneration in mice with glycerol-induced muscle injury (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). TBT upregulated protein expression levels of Atrogin-1, MuRF1, myostatin, and phosphorylated AMPKα and downregulated protein expression level of phosphorylated FoxO1 in the mouse soleus muscles (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). CONCLUSIONS: This study demonstrates for the first time that low-dose TBT significantly inhibits myogenic differentiation and triggers myotube atrophy in a cell model and significantly decreases muscle regeneration and muscle mass and function in a mouse model. These findings suggest that low-dose TBT exposure may be an environmental risk factor for muscle regeneration inhibition, atrophy/wasting, and disease-related myopathy.

Low-dose tributyltin triggers human chondrocyte senescence and mouse articular cartilage aging.

Tributyltin (TBT) is known as an endocrine-disrupting chemical. This study investigated the effects and possible mechanisms of TBT exposure on inducing human articular chondrocyte senescence in vitro at the human-relevant concentrations of 0.01-0.5 µM and mouse articular cartilage aging in vivo at the doses of 5 and 25 µg/kg/day, which were 5 times lower than the established no observed adverse effect level (NOAEL) and equal to NOAEL, respectively. TBT significantly increased the senescence-associated ß-galactosidase activity and the protein expression levels of senescence markers p16, p53, and p21 in chondrocytes. TBT induced the protein phosphorylation of both p38 and JNK mitogen-activated protein kinases in which the JNK signaling was a main pathway to be involved in TBT-induced chondrocyte senescence. The phosphorylation of both ataxia-telangiectasia mutated (ATM) and histone protein H2AX (termed γH2AX) was also significantly increased in TBT-treated chondrocytes. ATM inhibitor significantly inhibited the protein expression levels of γH2AX, phosphorylated p38, phosphorylated JNK, p16, p53, and p21. TBT significantly stimulated the mRNA expression of senescence-associated secretory phenotype (SASP)-related factors, including IL-1ß, TGF-ß, TNF-α, ICAM-1, CCL2, and MMP13, and the protein expression of GATA4 and phosphorylated NF-κB-p65 in chondrocytes. Furthermore, TBT by oral gavage for 4 weeks in mice significantly enhanced the articular cartilage aging and abrasion. The protein expression of phosphorylated p38, phosphorylated JNK, GATA4, and phosphorylated NF-κB-p65, and the mRNA expression of SASP-related factors were enhanced in the mouse cartilages. These results suggest that TBT exposure can trigger human chondrocyte senescence in vitro and accelerating mouse articular cartilage aging in vivo.

Can a Bayesian belief network for survival prediction in patients with extremity metastases (PATHFx) be externally validated in an Asian cohort of 356 surgically treated patients?

BACKGROUND AND PURPOSE: Predicted survival may influence the treatment decision for patients with skeletal extremity metastasis, and PATHFx was designed to predict the likelihood of a patient dying in the next 24 months. However, the performance of prediction models could have ethnogeographical variations. We asked if PATHFx generalized well to our Taiwanese cohort consisting of 356 surgically treated patients with extremity metastasis. PATIENTS AND METHODS: We included 356 patients who underwent surgery for skeletal extremity metastasis in a tertiary center in Taiwan between 2014 and 2019 to validate PATHFx's survival predictions at 6 different time points. Model performance was assessed by concordance index (c-index), calibration analysis, decision curve analysis (DCA), Brier score, and model consistency (MC). RESULTS: The c-indexes for the 1-, 3-, 6-, 12-, 18-, and 24-month survival estimations were 0.71, 0.66, 0.65, 0.69, 0.68, and 0.67, respectively. The calibration analysis demonstrated positive calibration intercepts for survival predictions at all 6 timepoints, indicating PATHFx tended to underestimate the actual survival. The Brier scores for the 6 models were all less than their respective null model's. DCA demonstrated that only the 6-, 12-, 18-, and 24-month predictions appeared useful for clinical decision-making across a wide range of threshold probabilities. The MC was < 0.9 when the 6- and 12-month models were compared with the 12-month and 18-month models, respectively. INTERPRETATION: In this Asian cohort, PATHFx's performance was not as encouraging as those of prior validation studies. Clinicians should be cognizant of the potential decline in validity of any tools designed using data outside their particular patient population. Developers of survival prediction tools such as PATHFx might refine their algorithms using data from diverse, contemporary patients that is more reflective of the world's population.