Bisphosphonates and mortality: confounding in observational studies?

Molecularly Imprinted Macroporous Hydrogel Promotes Bone Regeneration via Osteogenic Induction and Osteoclastic Inhibition

Macroporous hydrogels offer physical supportive spaces and bio-instructive environment for the seeded cells, where cell-scaffold interactions directly influence cell fates and subsequently affect tissue regeneration post-implantation. Effectively modifying bioactive motifs at the inner pore surface provides appropriate niches for cell-scaffold interactions. A molecular imprinting method and sacrificial templates are introduced to prepare inner pore surface modification in the macroporous hydrogels. In detail, acrylated bisphosphonates (Ac-BPs) chelating to templates (CaCO3 particles) are anchored on the inner pore surface of the methacrylated gelatin (GelMA)-methacrylated hyaluronic acid (HAMA)-poly (ethylene glycol) diacrylate (PEGDA) macroporous hydrogel (GHP) to form a functional hydrogel scaffold (GHP-int-BP). GHP-int-BP, but not GHP, effectively crafts artificial cell niches to substantially alter cell fates, including osteogenic induction and osteoclastic inhibition, and promote in situ bone regeneration. These findings highlight that molecular imprinting on the inner pore surface in the hydrogel efficiently creates orthogonally additive bio-instructive scaffolds for bone regeneration.

Using machine-learning to decode postoperative hip mortality Trends: Actionable insights from an extensive clinical dataset

BACKGROUND

Hip fractures are one of the most common injuries experienced by the general population. Despite advances in surgical techniques, postoperative mortality rates remain high. identifying relevant clinical factors associated with mortality is essential to preoperative risk stratification and tailored post-surgical interventions to improve patient outcomes. The purpose of this study aimed to identify preoperative risk factors and develop predictive models for increased hip fracture-related mortality within 30 days post-surgery, using one of the largest patient cohorts to date.

METHODS

Data from the American College of Surgeons National Surgical Quality Improvement Program database, comprising 107,660 hip fracture patients treated with surgical fixation was used. A penalized regression approach, least absolute shrinkage and selection operator was employed to develop two predictive models: one using preoperative factors and the second incorporating both preoperative and postoperative factors.

RESULTS

The analysis identified 68 preoperative factor outcomes associated with 30-day mortality. The combined model revealed 84 relevant factors, showing strong predictive power for determining postoperative mortality, with an AUC of 0.83.

CONCLUSIONS

The study's comprehensive methodology provides risk assessment tools for clinicians to identify high-risk patients and optimize patient-specific care.

Potential Geroprotectors - From Bench to Clinic

Geroprotectors are substances that slow down aging process and can be used for prevention of age-related diseases. Geroprotectors can improve functioning of various organ systems and enhance their homeostatic capabilities. We have developed a system of criteria for geroprotectors and proposed their classification based on the mechanisms of their action on the aging processes. Geroprotectors are required to reduce mortality, improve human aging biomarkers, have minimal side effects, and enhance quality of life. Additionally, there are approaches based on combining geroprotectors targeted to different targets and mechanisms of aging to achieve maximum effectiveness. Currently, numerous preclinical studies are being conducted to identify new molecular targets and develop new approaches to extend healthy aging, although the number of clinical trials is limited. Geroprotectors have the potential to become a new class of preventive medicines as they prevent onset of certain diseases or slow down their progression.

Detecting Selection Bias in Observational Studies-When Interventions Work Too Fast

This Viewpoint discusses the limitations that observational studies have in drawing causal inferences.

Geriatric nutritional risk index as the prognostic factor in older patients with fragility hip fractures

This study investigated the long-term survival and incidence of secondary fractures after fragility hip fractures. The 5-year survival rate was 62%, and the mortality risk was seen in patients with GNRI < 92. The 5-year incidence of secondary fracture was 22%, which was significantly higher in patients with a BMI < 20.

BACKGROUND

Malnutrition negatively influences the postoperative survival of patients with fragility hip fractures (FHFs); however, little is known about their association over the long term.

OBJECTIVE

This study evaluated the ability of the geriatric nutritional risk index (GNRI) as a risk factor for long-term mortality after FHFs.

METHODS

This study included 623 Japanese patients with FHFs over the age of 60 years. We prospectively collected data on admission and during hospitalization and assessed the patients' conditions after discharge through a questionnaire. We examined the long-term mortality and the incidence of secondary FHFs and assessed the prognostic factors.

RESULTS

The mean observation period was 4.0 years (range 0-7 years). The average age at the time of admission was 82 years (range 60-101 years). The overall survival after FHFs (1 year, 91%; 5 years, 62%) and the incidence of secondary FHFs were high (1 year, 4%; 5 years, 22%). The multivariate Cox proportional hazard analysis revealed the risk factors for mortality as older age (hazard ratio [HR] 1.04), male sex (HR 1.96), lower GNRI score (HR 0.96), comorbidities (malignancy, HR 2.51; ischemic heart disease, HR 2.24; revised Hasegawa dementia scale ≤ 20, HR 1.64), no use of active vitamin D3 on admission (HR 0.46), and a lower Barthel index (BI) (on admission, HR 1.00; at discharge, HR 0.99). The GNRI scores were divided into four risk categories: major risk (GNRI, < 82), moderate risk (82-91), low risk (92-98), and no risk (> 98). Patients at major and moderate risks of GNRI had a significantly lower overall survival rate (p < 0.001). Lower body mass index (BMI) was also identified as a prognostic factor for secondary FHFs (HR 0.88 [p = 0.004]).

CONCLUSIONS

We showed that older age, male sex, a lower GNRI score, comorbidities, and a lower BI are risk factors for mortality following FHFs. GNRI is a novel and simple predictor of long-term survival after FHFs.

Pros and Cons of Skeletal Medications in the COVID-19 Era

Purpose of Review

This review provides an overview regarding osteoporosis therapies during the COVID-19 pandemic.

Recent Findings

The COVID-19 pandemic has disrupted treatments for osteoporosis and resulted in decreased adherence particularly for parenteral regimens. Osteoporosis medications are safe and effective during the pandemic and should be continued whenever possible. Bisphosphonates have long-lasting effects on bone turnover such that delays in their administration are unlikely to be harmful to skeletal health. In contrast, interruption of denosumab treatment is strongly discouraged because of rapid loss of bone mass and an associated increased risk for rebound vertebral fractures. When osteoanabolic treatments cannot be continued during the pandemic, change to an oral bisphosphonate is advised. Preclinical data suggest possible beneficial effects of some therapies against COVID-19, but require validation in clinical studies. Vitamin D deficiency is associated with a more severe COVID-19 clinical course but data supporting improvements in outcomes with vitamin D supplementation are lacking.

Summary

The impact of the COVID-19 pandemic on long-term bone health remains unknown but focused interventions to ensure osteoporosis treatment initiation/maintenance should be implemented. Future studies are needed to determine whether osteoporosis medications have an impact on SARS-CoV-2 pathophysiology and COVID-19 clinical outcomes.

Bisphosphonate-based hydrogel mediates biomimetic negative feedback regulation of osteoclastic activity to promote bone regeneration

The intricate dynamic feedback mechanisms involved in bone homeostasis provide valuable inspiration for the design of smart biomaterial scaffolds to enhance in situ bone regeneration. In this work, we assembled a biomimetic hyaluronic acid nanocomposite hydrogel (HA-BP hydrogel) by coordination bonds with bisphosphonates (BPs), which are antiosteoclastic drugs. The HA-BP hydrogel exhibited expedited release of the loaded BP in response to an acidic environment. Our in vitro studies showed that the HA-BP hydrogel inhibits mature osteoclastic differentiation of macrophage-like RAW264.7 cells via the released BP. Furthermore, the HA-BP hydrogel can support the initial differentiation of primary macrophages to preosteoclasts, which are considered essential during bone regeneration, whereas further differentiation to mature osteoclasts is effectively inhibited by the HA-BP hydrogel via the released BP. The in vivo evaluation showed that the HA-BP hydrogel can enhance the in situ regeneration of bone. Our work demonstrates a promising strategy to design biomimetic biomaterial scaffolds capable of regulating bone homeostasis to promote bone regeneration.

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HA-BP hydrogel can mediate the expedited release of BP in response to the acidic microenvironment created by osteoclasts.

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HA-BP hydrogel supports preosteoclastic differentiation, but inhibits the further osteoclastic maturation.

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The implantation of HA-BP hydrogel in critical-sized bone defects significantly promotes in situ bone regeneration in vivo.

Cardiovascular Safety and Effectiveness of Bisphosphonates: From Intervention Trials to Real-Life Data

Both osteoporosis with related fragility fractures and cardiovascular diseases are rapidly outspreading worldwide. Since they are often coexistent in elderly patients and may be related to possible common pathogenetic mechanisms, the possible reciprocal effects of drugs employed to treat these diseases have to be considered in clinical practice. Bisphosphonates, the agents most largely employed to decrease bone fragility, have been shown to be overall safe with respect to cardiovascular diseases and even capable of reducing cardiovascular morbidity in some settings, as mainly shown by real life studies. No randomized controlled trials with cardiovascular outcomes as primary endpoints are available. While contradictory results have emerged about a possible BSP-mediated reduction of overall mortality, it is undeniable that these drugs can be employed safely in patients with high fracture risk, since no increased mortality has ever been demonstrated. Although partial reassurance has emerged from meta-analysis assessing the risk of cardiac arrhythmias during bisphosphonates treatment, caution is warranted in administering this class of drugs to patients at risk for atrial fibrillation, possibly preferring other antiresorptives or anabolics, according to osteoporosis guidelines. This paper focuses on the complex relationship between bisphosphonates use and cardiovascular disease and possible co-management issues.

Reduced All-Cause Mortality with Bisphosphonates Among Post-Fracture Osteoporosis Patients: A Nationwide Study and Systematic Review

We assessed the survival outcomes associated with real-world bisphosphonate use, stratified by fracture site, type, administration, and duration of treatment, among patients with osteoporosis. A systematic review that incorporates our findings was conducted to provide up-to-date evidence on survival outcomes with bisphosphonate treatment in real-world settings. Patients diagnosed with osteoporosis who had been hospitalized for major fractures were identified from Taiwan's National Health Insurance Research Database 2008-2017 and followed until 2018. There were 24,390 new bisphosphonate users who were classified and compared with 76,725 nonusers of anti-osteoporosis medications in terms of survival outcomes using Cox model analysis. An inverse probability of treatment weighted Cox model and landmark analyses for minimizing immortal time bias were also performed. Bisphosphonate users vs. nonusers had a significantly lower mortality risk, regardless of fracture site (hazard ratios (95% confidence intervals) for patients with any major fracture, hip fracture, and vertebral fracture: 0.90 (0.88, 0.93), 0.83 (0.80, 0.86), and 0.86 (0.82, 0.89), respectively). Compared with nonuse, zoledronic acid (0.77 (0.73, 0.82)) was associated with the lowest mortality, followed by ibandronate (0.85 (0.78, 0.93)) and alendronate/risedronate (0.93 (0.91, 0.96)). Using bisphosphonates for ≥ 3 years had lower mortality (0.60 (0.53, 0.67)) than using bisphosphonates for < 3 years (0.98 (0.95, 1.01)). Intravenous bisphosphonates had a lower mortality than that of oral bisphosphonates. Our results are consistent with the systematic review findings among real-world populations. In conclusion, bisphosphonate use, especially persistence to intravenous bisphosphonates (e.g., zoledronic acid), may reduce post-fracture mortality among patients with osteoporosis, particularly those with hip/vertebral fractures. This supports the rational use of bisphosphonates in post-fracture care.

Real-World Effectiveness of Anti-Resorptive Treatment in Patients With Incident Fragility Fractures-The STORM Cohort-A Swedish Retrospective Observational Study

Results from real-world evidence (RWE) from the largest healthcare region in Sweden show low uptake of antiresorptive (AR) treatment, but beneficial effect in those receiving treatment, especially for the composite outcome of hip fracture or death. For RWE studies, Sweden is unique, with virtually complete coverage of electronic medical records (EMRs) and both regional and national registries, in a universal publicly funded healthcare system. To our knowledge, there is no previous RWE study evaluating the efficacy of AR treatment compared to no AR treatment after fragility fracture, including data on parenteral treatments administered in hospital settings. The Stockholm Real World Management (STORM) study cohort was established in the healthcare region of Stockholm to retrospectively assess the effectiveness of AR treatment after first fragility fracture using the regional EMR system for both hospital and primary care. Between 2012 and 2018, we identified 69,577 fragility fracture episodes among 59,078 patients, men and women, 50 years and older. Of those, 21,141 patients met inclusion and exclusion criteria (eligible cohort). From these, the final matched study cohort comprised 9840 fragility fractures (cases receiving AR treatment [n = 1640] and controls not receiving AR treatment [n = 8200]). Propensity scores were estimated using logistic regression models with AR treatment as outcome and confounders as independent variables followed by analysis using Cox proportional hazard models. Real world evidence from Sweden's largest healthcare region, comprising a quarter of the Swedish population, show that only 10% of patients receive AR treatment within 1 year after a fragility fracture. Factors associated with not receiving treatment include having a diagnosis of cardiovascular disease. In those treated, AR have positive effects particularly on the composite of fracture and death (any fracture/death and hip fracture/death) in individuals matched for all major confounders. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

All-cause mortality risk in aged femoral intertrochanteric fracture patients

Introduction

The 1-year mortality rate after femoral intertrochanteric fracture is higher than that of femoral neck fracture, which also belongs to hip fracture (Cui et al. in Arch Osteoporos 14(1):55, 2019). With the application of the concept of co-management model of orthopedics and geriatrics, the short-term and long-term mortality of all types of hip fractures has decreased (Van Heghe et al. in Calcif Tissue Int, 2021, https://doi.org/10.1007/s00223-021-00913-5). However, the mortality of Chinese femoral intertrochanteric fracture patients under this model has not been reported in the literatures.

Aim

This paper aims to study the risk factors of postoperative all-cause mortality in aged patients with femoral intertrochanteric fracture under the co-management model of orthopedics and geriatrics.

Materials and methods

This is a single-center prospective cohort study based on the real world, under the co-management of orthopedics and geriatrics, 363 patients aged ≥ 65 years with femoral intertrochanteric fracture were enrolled and followed up for 2–3 years; 52 patients were lost to follow up. Age, gender, body mass index (BMI), history of comorbidities, hip Bone Mineral Density (BMD), fracture history, 25(OH)D level, hemoglobin level, anti-osteoporosis treatment were risk factors to be tested. Kaplan–Meier survival curves and multivariate Cox proportional hazards models were constructed to analyze the impact of factors on all-cause mortality.

Results

(1) Most of the dead patients were older (the mean age was 83.4 years, compared with 79.8 years for surviving patients), with more complications and without anti-osteoporosis medication; gender, pre-fracture history, BMI, total hip BMD, hemoglobin, 25(OH)D had no difference between the dead and the living patients. (2) Elderly patients with Intertrochanteric fracture can benefit from the early treatment of Zoledronic Acid (within 3 days after the operation).

Conclusion

Under the co-management of orthopedics and geriatrics, to Chinese patients with Femoral Intertrochanteric fracture, Doctors should pay more attention to their age and chronic disease, and give anti-osteoporosis treatment if allowed.

Fracture recurrence in hip fracture with menopausal hormone therapy versus risedronate: a clinical trial

OBJECTIVES

An open-label, randomized trial was conducted to examine the effects of risedronate versus menopausal hormone therapy (MHT) in postmenopausal women with recent hip fracture.

METHODS

Among 1165 eligible women, 281 were recruited and randomly assigned to receive oral risedronate (35 mg/week) or percutaneous estradiol gel (1.5 mg/day) plus oral micronized progesterone (100 mg/day) for 4 years. The primary end point was recurrent fracture and the secondary end points were mortality and bone mineral density (BMD).

RESULTS

Kaplan-Meier analyses showed no significant differences in fracture recurrence and mortality between the two groups. The incidence of any new fracture per 100 person-years (PY) was 8.63 in the risedronate group and 12.86 in the MHT group (p = 0.180); that of clinical fracture was 4.75 and 6.99, respectively (p = 0.265); and that of asymptomatic vertebral fracture was 4.87 and 5.58, respectively (p = 0.764). The respective incidence of death per 100 PY was 3.58 and 4.40 (p = 0.503). BMD increased comparably at the lumbar spine in both groups. BMD at the total hip did not change in the risedronate group, but increased significantly by 2.8% in the MHT group.

CONCLUSIONS

MHT might not differ from risedronate in the prevention of secondary fractures and death among postmenopausal women with recent hip fracture.

Adherence to Anti-Osteoporotic Treatment and Clinical Implications after Hip Fracture: A Systematic Review

The role of anti-osteoporotic treatment as part of the secondary prevention after hip fracture in terms of mortality and re-fracture risk has been studied, and the results are promising. Decreased treatment adherence and compliance is a problem that needs to be addressed by healthcare professionals. A systematic review of the literature was performed using the PubMed database with terms that included hip fracture, mortality, second fracture, and specific anti-osteoporotic treatment. We included 28 articles, 21 regarding mortality and 20 re-fracture rates in hip fracture patients. All studies showed lower mortality after hip fracture associated with anti-osteoporotic treatment, mostly bisphosphonate agents. The re-fracture risk is still debatable, since conflicting data were found. Although most of the studies showed notable effects on mortality and re-fracture rates associated with anti-osteoporotic treatment, we still need more data to validate the actual results.

Common methodological issues and suggested solutions in bone research

Bone research is a dynamic area of scientific investigation that usually encompasses multidisciplines. Virtually all basic cellular research, clinical research and epidemiologic research rely on statistical concepts and methodology for inference. This paper discusses common issues and suggested solutions concerning the application of statistical thinking in bone research, particularly in clinical and epidemiological investigations. The issues are sample size estimation, biases and confounders, analysis of longitudinal data, categorization of continuous data, selection of significant variables, over-fitting, P-values, false positive finding, confidence interval, and Bayesian inference. It is hoped that by adopting the suggested measures the scientific quality of bone research can improve.

Bisphosphonates and lifespan

Bisphosphonates are first line agents used to treat osteoporosis and reduce fracture rate. They bind to areas of exposed calcium in the skeleton and cause osteoclast apoptosis, thereby leading to a reduction in remodelling rates. They are also used to decrease skeletal complications of some cancers including a reduction in bone metastases. Following the landmark randomised controlled trial of zoledronate post hip fracture (HORIZON) in which an unexpected survival benefit was found, there has been increasing interest in their potential ability to increase lifespan. This review will consider the clinical evidence for their effect on mortality in both the osteoporosis and non-osteoporosis settings, the latter including studies in intensive care, cancer and cardiovascular disease. Where evidence exists, this review will briefly discuss some of the postulated mechanisms for this survival benefit.

Influence of anti-osteoporosis treatments on the incidence of COVID-19 in patients with non-inflammatory rheumatic conditions

Coronavirus disease 19 (COVID-19) is currently a global pandemic that affects patients with other pathologies. Here, we investigated the influence of treatments for osteoporosis and other non-inflammatory rheumatic conditions, such as osteoarthritis and fibromyalgia, on COVID-19 incidence. To this end, we conducted a cross-sectional study of 2,102 patients being treated at the Rheumatology Service of Hospital del Mar (Barcelona, Spain). In our cohort, COVID-19 cumulative incidence from March 1 to May 3, 2020 was compared to population estimates for the same city. We used Poisson regression models to determine the adjusted relative risk ratios for COVID-19 associated with different treatments and comorbidities. Denosumab, zoledronate and calcium were negatively associated with COVID-19 incidence. Some analgesics, particularly pregabalin and most of the studied antidepressants, were positively associated with COVID-19 incidence, whereas duloxetine presented a negative association. Oral bisphosphonates, vitamin D, thiazide diuretics, anti-hypertensive drugs and chronic non-steroidal anti-inflammatory drugs had no effect on COVID-19 incidence in the studied population. Our results provide novel evidence to support the maintenance of the main anti-osteoporosis treatments in COVID-19 patients, which may be of particular relevance to elderly patients affected by the SARS-CoV-2 pandemic.

Benefits of Bisphosphonate Therapy: Beyond the Skeleton

PURPOSE OF REVIEW

Recent evidence from clinical trials and observational studies raises the possibility that bisphosphonate use might confer a lower risk of cardiovascular disease and cancer, resulting in a mortality benefit. This review summarizes clinical and preclinical studies examining the non-skeletal effects of bisphosphonates.

RECENT FINDINGS

Data from clinical trials are conflicting regarding whether or not bisphosphonates have beneficial effects on mortality, cardiovascular events, or cancer incidence. No clinical trials have assessed these outcomes as primary endpoints, and most trials were shorter than 4 years. Observational data suggest that bisphosphonate users may have lower mortality, delayed progression of vascular calcification and atherosclerotic burden, and reduced incidence of breast and colorectal cancer compared to non-users. Preclinical studies confirm that bisphosphonates can be taken up by macrophages and monocytes, and nitrogen-containing bisphosphonates have the ability to disrupt the mevalonate pathway within these cells. In this manner, bisphosphonates exert anti-atherogenic and anti-cancer effects. Bisphosphonates also appear to exert protective effects on vascular smooth muscle cells and endothelial cells and may have direct cytotoxic effects on cancer cells. The balance of evidence does not support bisphosphonate treatment for the primary purpose of improving non-skeletal outcomes, although appropriately designed controlled trials that further explore this possibility are both justified and required. Patients with skeletal indications for bisphosphonate therapy can be reassured that these agents are not associated with increased mortality, cardiovascular disease, or cancer incidence.

Disentangling the contribution of hospitals and municipalities for understanding patient level differences in one-year mortality risk after hip-fracture: A cross-classified multilevel analysis in Sweden

Background

One-year mortality after hip-fracture is a widely used outcome measure when comparing hospital care performance. However, traditional analyses do not explicitly consider the referral of patients to municipality care after just a few days of hospitalization. Furthermore, traditional analyses investigates hospital (or municipality) variation in patient outcomes in isolation rather than as a component of the underlying patient variation. We therefore aimed to extend the traditional approach to simultaneously estimate both case-mix adjusted hospital and municipality comparisons in order to disentangle the amount of the total patient variation in clinical outcomes that was attributable to the hospital and municipality level, respectively.

Methods

We determined 1-year mortality risk in patients aged 65 or above with hip fractures registered in Sweden between 2011 and 2014. We performed cross-classified multilevel analysis with 54,999 patients nested within 54 hospitals and 290 municipalities. We adjusted for individual demographic, socioeconomic and clinical characteristics. To quantify the size of the hospital and municipality variation we calculated the variance partition coefficient (VPC) and the area under the receiver operator characteristic curve (AUC).

Results

The overall 1-year mortality rate was 25.1%. The case-mix adjusted rates varied from 21.7% to 26.5% for the 54 hospitals, and from 18.9% to 29.5% for the 290 municipalities. The VPC was just 0.2% for the hospital and just 0.1% for the municipality level. Patient sociodemographic and clinical characteristics were strong predictors of 1-year mortality (AUC = 0.716), but adding the hospital and municipality levels in the cross-classified model had a minor influence (AUC = 0.718).

Conclusions

Overall in Sweden, one-year mortality after hip-fracture is rather high. However, only a minor part of the patient variation is explained by the hospital and municipality levels. Therefore, a possible intervention should be nation-wide rather than directed to specific hospitals or municipalities.