Randomized trial of the effects of risedronate on vertebral fractures in women with established postmenopausal osteoporosis. Vertebral Efficacy with Risedronate Therapy (VERT) Study Group

The Effects of Osteoporotic and Non-osteoporotic Medications on Fracture Risk and Bone Mineral Density

Osteoporosis is a highly prevalent bone disease affecting more than 37.5 million individuals in the European Union (EU) and the  United States of America (USA). It is characterized by low bone mineral density (BMD), impaired bone quality, and loss of structural and biomechanical properties, resulting in reduced bone strength. An increase in morbidity and mortality is seen in patients with osteoporosis, caused by the approximately 3.5 million new osteoporotic fractures occurring every year in the EU. Currently, different medications are available for the treatment of osteoporosis, including anti-resorptive and osteoanabolic medications. Bisphosphonates, which belong to the anti-resorptive medications, are the standard treatment for osteoporosis based on their positive effects on bone, long-term experience, and low costs. However, not only medications used for the treatment of osteoporosis can affect bone: several other medications are suggested to have an effect on bone as well, especially on fracture risk and BMD. Knowledge about the positive and negative effects of different medications on both fracture risk and BMD is important, as it can contribute to an improvement in osteoporosis prevention and treatment in general, and, even more importantly, to the individual's health. In this review, we therefore discuss the effects of both osteoporotic and non-osteoporotic medications on fracture risk and BMD. In addition, we discuss the underlying mechanisms of action.

Dose-dependent effects of pharmaceutical treatments on bone matrix properties in ovariectomized rats

As both anabolic and anti-catabolic osteoporosis drugs affect bone formation and resorption processes, they may contribute to bone's overall mechanical behavior by altering the quality of the bone matrix. We used an ovariectomized rat model and a novel fracture mechanics approach to investigate whether treatment with an anabolic (parathyroid hormone) or anti-catabolic (alendronate) osteoporosis drugs will alter the organic and mineral matrix components and consequently cortical bone fracture toughness. Ovariectomized (at 5 months age) rats were treated with either parathyroid hormone or alendronate at low and high doses for 6 months (age 6–12 months). Specifically, treatment groups included untreated ovariectomized controls (n = 9), high-dose alendronate (n = 10), low-dose alendronate (n = 9), high-dose parathyroid hormone (n = 10), and low-dose parathyroid hormone (n = 9). After euthanasia, cortical microbeams from the lateral quadrant were extracted, notched, and tested in 3-point bending to measure fracture toughness. Portions of the bone were used to measure changes in the 1) organic matrix through quantification of advanced glycation end-products (AGEs) and non-collagenous proteins, and 2) mineral matrix through assessment of mineral crystallinity. Compared to the ovariectomized group, rats treated with high doses of parathyroid hormone and alendronate had significantly increased cortical bone fracture toughness, which corresponded primarily to increased non-collagenous proteins while there was no change in AGEs. Additionally, low-dose PTH treatment increased matrix crystallinity and decreased AGE levels. In summary, ovariectomized rats treated with pharmaceutical drugs had increased non-collagenous matrix proteins and improved fracture toughness compared to controls. Further investigation is required for different doses and longer treatment periods.

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Alendronate increases non-collagenous proteins and improves fracture toughness.

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Parathyroid hormone also increases collagen maturity and mineral crystallinity.

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Both treatments minimize accumulation of advanced glycation end-products.

Alendronate use in older patients with reduced renal function: challenges and opportunities in clinical practice

In this retrospective cohort study, alendronate use among older osteoporosis patients (age>65 years) with reduced renal function (creatinine clearance<35ml/min) was not associated with significant deterioration in renal function from baseline nor increased incidence of osteoporotic fractures or acute kidney injury, compared with patients conservatively managed with only calcium/vitamin D supplementation.

INTRODUCTION

Oral bisphosphonates are not recommended in patients with creatinine clearance (CrCl) <35ml/min, although this is not supported by post hoc analyses of pivotal oral bisphosphonate studies. As both osteoporosis and renal insufficiency are more prevalent with advancing age, it is important to determine the safety and efficacy of oral bisphosphonates among these patients.

METHODS

Patients with CrCl <35ml/min on alendronate (group A, n=98), with CrCl <35ml/min conservatively managed (group B, n=96), and with CrCl ≥35ml/min on alendronate (group C, n=96) were followed up to 22 months. Primary outcomes were mean change in CrCl from baseline in group A compared with groups B and C, respectively. Secondary outcomes were the incidence of osteoporotic fractures and adverse events between groups.

RESULTS

There was no significant change in CrCl from baseline when comparing group A (-1.53±6.83ml/min) with group B (0.59±5.17ml/min) (p=0.075), and group A with group C (-3.71±7.54ml/min) (p=0.163). There was no significant increase in incidences of osteoporotic fractures in group A compared with group B (adjusted relative risk (aRR) 2.02, 95% confidence interval (CI) 0.64-6.37) and group A compared with group C (aRR 1.15, 95% CI 0.46-2.89). There was no significant difference in incidences of acute kidney injury (AKI) in group A compared with group B (aRR 0.48, 95% CI 0.20-1.12). Although statistically non-significant, there was an increase in AKI incidence in group A compared with group C (RR 7.84, 95% CI 0.98-62.66).

CONCLUSION

Among patients with CrCl <35ml/min, alendronate therapy was not associated with significant deterioration in renal function from baseline. Although not powered for secondary outcomes, there were no statistically significant differences in osteoporotic fracture or AKI incidence between the groups.

Management of osteoporosis in postmenopausal women: the 2021 position statement of The North American Menopause Society

OBJECTIVE

To review evidence regarding osteoporosis screening, prevention, diagnosis, and management in the past decade and update the position statement published by The North American Menopause Society (NAMS) in 2010 regarding the management of osteoporosis in postmenopausal women as new therapies and paradigms have become available.

DESIGN

NAMS enlisted a panel of clinician experts in the field of metabolic bone diseases and/or women's health to review and update the 2010 NAMS position statement and recommendations on the basis of new evidence and clinical judgement. The panel's recommendations were reviewed and approved by the NAMS Board of Trustees.

RESULTS

Osteoporosis, especially prevalent in older postmenopausal women, increases the risk of fractures that can be associated with significant morbidity and mortality. Postmenopausal bone loss, related to estrogen deficiency, is the primary contributor to osteoporosis. Other important risk factors for postmenopausal osteoporosis include advanced age, genetics, smoking, thinness, and many diseases and drugs that impair bone health. An evaluation of these risk factors to identify candidates for osteoporosis screening and recommending nonpharmacologic measures such as good nutrition (especially adequate intake of protein, calcium, and vitamin D), regular physical activity, and avoiding smoking and excessive alcohol consumption are appropriate for all postmenopausal women. For women at high risk for osteoporosis, especially perimenopausal women with low bone density and other risk factors, estrogen or other therapies are available to prevent bone loss. For women with osteoporosis and/or other risk factors for fracture, including advanced age and previous fractures, the primary goal of therapy is to prevent new fractures. This is accomplished by combining nonpharmacologic measures, drugs to increase bone density and to improve bone strength, and strategies to reduce fall risk. If pharmacologic therapy is indicated, government-approved options include estrogen agonists/antagonists, bisphosphonates, RANK ligand inhibitors, parathyroid hormone-receptor agonists, and inhibitors of sclerostin.

CONCLUSIONS

Osteoporosis is a common disorder in postmenopausal women. Management of skeletal health in postmenopausal women involves assessing risk factors for fracture, reducing modifiable risk factors through dietary and lifestyle changes, and the use of pharmacologic therapy for patients at significant risk of osteoporosis or fracture. For women with osteoporosis, lifelong management is necessary. Treatment decisions occur continuously over the lifespan of a postmenopausal woman. Decisions must be individualized and should include the patient in the process of shared decision-making.

Breast cancer therapy and bone

Breast cancer is the most common cancer in women and the leading cause of cancer-associated mortality. The estrogen deprivation associated with therapies used to treat this disease may result in significant loss of bone density and a consequent increase in fracture risk. Anti-resorptive osteoporosis therapies (bisphosphonates and the inhibitor of receptor activator of nuclear factor-κB ligand [RANKL] denosumab) play an important role in the mitigation of cancer therapy-induced bone loss (CTIBL), and may function as adjuvant therapy in moderate to high-risk breast cancer to prevent disease recurrence. Various international guidelines have delineated treatment thresholds based on both bone density assessment and clinical risk factors for CTIBL. The role of these bone-targeted therapies as adjuvant anti-cancer treatment is evolving. Currently, evidence supports the use of the bisphosphonates, zoledronic acid and clodronate, in this setting. Unfortunately, a focus on bone health in women with breast cancer is often not prioritized, leaving this group vulnerable to significant bone loss and subsequent fracture.

Medical treatment of osteoporosis

Osteoporosis is a common chronic condition that markedly increases the risk of fractures. Osteoporotic-related fractures increase morbidity and mortality and impair quality of life. Therefore, a correct approach for fracture prevention seems mandatory. Lifestyle changes should be recommended to all patients, including weight reduction if patients are obese/overweight, increasing physical activity and avoiding alcohol consumption and smoking. Additionally, calcium and vitamin D3 should be prescribed until the vitamin D deficit is resolved. Osteoporosis treatment options mainly include antiresorptives (i.e. estrogens, selective estrogen receptor modulators, bisphosphonates, denosumab) and anabolic agents (i.e. teriparatide, abaloparatide, romosozumab). Although presenting differences in efficacy and side effects, they have all been shown to increase bone mineral density (BMD) and to reduce osteoporotic-related fractures. Monotherapy with antiresorptive agents, particularly oral bisphosphonates, should be considered routinely as the first option for treatment of postmenopausal women. However, in the case of side effects, therapeutic failure or the need for long-term use, anabolic agents may be considered. In high-risk patients, anabolic agents may be considered as an initial therapeutic option. The combination of antiresorptive and anabolic agents may be useful to increase BMD compared with monotherapy, but more information is warranted to determine the effects on fracture risk.

Efficacy and efficiency of fracture liaison services to reduce the risk of recurrent osteoporotic fractures

Background

Acting to prevent the next fracture after a sentinel fracture is support by the evidence base and brings benefits for patients, clinicians and healthcare systems. However, more patients after a fragility fracture remain untreated and vulnerable to future potentially life-changing fractures. Fracture liaison services (FLS) are models of care that can close this care gap.

Methods

A narrative review of the key evidence for the efficacy and effectiveness of FLS was performed

Results

There are few randomised control trials of FLSs and none with fracture as the primary outcome. Several observational studies have also demonstrated reductions in fracture, but most were limited by potential bias. Several studies have highlighted that not every FLS is automatically effective.

Conclusion

Further research should focus on implementing effective FLS using published standards and only then exploring impacts on patient outcomes such as refracture rates.

Anxiety Levels Predict Bone Mineral Density in Postmenopausal Women Undergoing Oral Bisphosphonates: A Two-Year Follow-Up

Clinical psychological factors may predict medical diseases. Anxiety level has been associated with osteoporosis, but its role on bone mineral density (BMD) change is still unknown. This study aimed to investigate the association between anxiety levels and both adherence and treatment response to oral bisphosphonates (BPs) in postmenopausal osteoporosis. BMD and anxiety levels were evaluated trough dual-energy X-ray absorptiometry and the Hamilton Anxiety Rating Scale (HAM-A), respectively. Participants received weekly medication with alendronate or risedronate and were grouped according to the HAM-A scores into tertiles (HAM-A 3 > HAM-A 2 > HAM-A 1). After 24 months, BMD changes were different among the HAM-A tertiles. The median lumbar BMD change was significantly greater in both the HAM-A 2 and HAM-A 3 in comparison with the HAM-A 1. The same trend was observed for femoral BMD change. Adherence to BPs was >75% in 68% of patients in the HAM-A 1, 79% of patients in the HAM-A 2, and 89% of patients in the HAM-A 3 (p = 0.0014). After correcting for age, body mass index, depressive symptoms, and the 10-yr. probability of osteoporotic fractures, anxiety levels independently predicted lumbar BMD change (β = 0.3417, SE 0.145, p = 0.02). In conclusion, women with higher anxiety levels reported greater BMD improvement, highlighting that anxiety was associated with adherence and response to osteoporosis medical treatment, although further research on this topic is needed.

Meta-analysis of clinical fracture risk reduction of anti-osteoporosis drugs: direct and indirect comparisons and meta-regressions

OBJECTIVE

Anti-osteoporotic drug (AOD) trials have variabilities in duration and fracture risks. This study evaluated AOD's versus controls regarding reduction in relative rates (rr) and rate differences (rd) of vertebral and hip fractures and comparative costs.

METHODS

Primary randomized-controlled trials (RCT's) of AOD's in post-menopausal women with documentation of vertebral fracture rates (VFR) or hip fracture rates (HFR) were extracted from meta-analyses and PubMed through February 2021. Direct and indirect meta-analysis and meta-regression analyzed fracture reductions.

RESULTS

There were 24 RCT's of drug-versus-placebo (73,862 women) and 10 drug-versus-drug trials. Reduction in rr of VFR were significant for anti-resorptive (alendronate, risedronate, zoledronate, denosumab, raloxifene) and anabolic (teriparatide, abaloparatide, romosozumab) drugs. Denosumab, teriparatide and abaloparatide were more effective in reducing VFR compared to oral bisphosphates (all p <0.05) but not to zoledronate. Reduction in HFR were significant for alendronate, denosumab and zoledronate (all p <0.05), without significant differences among drugs. Anabolic drugs did not show significant HFR reduction. Meta-regression of rd's allowed for calculation of costs per vertebral fracture prevented, which were estimated at >$100,000 for anabolic drugs and between $2,289-$28,947 for anti-resorptive drugs. Drug-versus-drug trials were underpowered to demonstrate changes.

CONCLUSIONS

This study suggests goal-directed, cost-effective therapy relative to a patient's risk for vertebral and hip fractures. Anabolic drugs are better at preventing vertebral fractures compared to oral bisphosphonates. Anabolic drugs are not superior to zoledronate or denosumab, and at substantially higher cost. In comparing drugs which prevented hip fractures, there was no statistical benefit of any drug.

The Treatment Gap in Osteoporosis

Worldwide, there are millions of people who have been diagnosed with osteoporosis, a bone disease that increases the risk of fracture due to low bone mineral density and deterioration of bone architecture. In the US alone, there are approximately ten million men and women diagnosed with osteoporosis and this number is still growing. Diagnosis is made by measuring bone mineral density. Medications used for the treatment of osteoporosis are bisphosphonates, denosumab, raloxifene, and teriparatide. Recently, romosozumab has been added as well. In recent years, a number of advances have been made in the field of diagnostic methods and the diverse treatment options for osteoporosis. Despite these advances and a growing incidence of osteoporosis, there is a large group being left undertreated or even untreated. This group of the under/untreated has been called the treatment gap. Concerns regarding rare side effects of the medications, such as osteonecrosis of the jaw, have been reported to be one of the many causes for the treatment gap. Also, this group seems not to be sufficiently informed of the major benefits of the treatment and the diversity in treatment options. Knowledge of these could be very helpful in improving compliance and hopefully reducing the gap. In this paper, we summarize recent evidence regarding the efficacy of the various treatment options, potential side effects, and the overall benefit of treatment.

Efficacy of annual zoledronic acid in initial percutaneous kyphoplasty patients with osteoporotic vertebral compression fractures: a 3-year follow-up study

This study investigated the efficacy of annual zoledronic acid (ZOL) administration against previously treated recompression vertebral fractures (RVF) and new vertebral fractures (NVF) in initial percutaneous kyphoplasty (PKP) patients with osteoporotic vertebral compression fractures (OVCF) over a 3-year follow-up period.

INTRODUCTION

Although PKP achieves a satisfactory outcome, previously treated RVF and NVF can limit its effectiveness. The annual infusion of ZOL over 3 years can improve fracture protection, particularly in the vertebrae. We hypothesized that ZOL can reduce the incidence of RVFs and/or NVFs, and improve the clinical outcomes of PKP.

METHODS

This was a placebo-controlled, double-blind prospective trial of 154 PKP patients (mean age: 70 years) with OVCFs. Patients were randomly assigned to receive a single infusion of ZOL (5 mg) or placebo (78 ZOL vs. 76 placebo) at 1 week, 12 months, and 24 months after surgery. Patients were followed-up for 36 months.

RESULTS

ZOL treatment lowered the risk of RVF by ~ 65% over the 36-month period when compared to placebo controls (6.41% in ZOL vs. 18.42% in placebo groups; relative risk, 0.35; 95% CI, 0.13 to 0.92). ZOL also reduced the risk of NVF by ~ 73% (3.85% in ZOL vs. 14.47% in placebo groups; relative risk, 0.27; 95% CI, 0.08 to 0.92). ZOL also significantly reduced the vertebral height lost rate (HLR) at 12, 24, and 36 months. ZOL also improved the visual analog scale (VAS), Oswestry disability index (ODI) scores, and bone mineral density (BMD).

CONCLUSION

Annual ZOL administration significantly lowers the risk of RVFs and NVFs, improving the clinical outcome of initial PKP in patients with OVCFs over a 3-year follow-up period.

TRIAL REGISTRATION

ChiCTR2000029307.

Cardiovascular Safety of Antifracture Medications in Patients With Osteoporosis: A Narrative Review of Evidence From Randomized Studies

Osteoporosis and cardiovascular (CV) disease share common risk factors and pathophysiology. Low bone mineral density (BMD) and fractures appear to increase the risk for multiple CV diseases. Equally, prevalent CV disease appears to predispose to bone loss and increase fracture rates. This relationship has naturally provoked the hypothesis that stopping bone loss may result in some CV benefit. Secondary analyses of safety and adverse event data from many randomized controlled trials (RCTs) have attempted to clarify this putative association. Recently, the discontinuation of odanacatib (anti-cathepsin K monoclonal antibody) over stroke concerns and the imbalance in ischemic events in romosozumab-treated (anti-sclerostin monoclonal antibody) women compared to bisphosphonate-treated women, has provided further justification to better characterize potential CV benefits and harms of osteoporosis medications. This review delves into the seminal, and other major RCTs of osteoporosis medications and, using both published data and additional information provided on trial registration pages, examines the evidence for CV safety and harms of these medications. Accepted and emerging "off-target" effects are explored for validity, biological plausibility, and clinical importance. A brief research agenda is provided to stimulate the next wave of clinical development and CV understanding of osteoporosis medications. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Update on Approved Osteoporosis Therapies Including Combination and Sequential Use of Agents

Osteoporosis is characterized by reduced bone mass leading to diminished skeletal integrity and an increased risk for fracture. Multiple agents exist that are effective for the treatment of osteoporosis. These can be broadly categorized into those that reduce the risk for additional loss of bone mass (anti-resorptive agents) and those that augment existing bone mass (anabolic agents). This article reviews the different medications within each class, and discusses more recent data regarding the combination and sequential use of these medications for optimization of skeletal health in patients at high risk for fracture.

Vitamin D Boosts Alendronate Tail Effect on Bone Mineral Density in Postmenopausal Women with Osteoporosis

Vitamin D modulates bisphosphonate (BP) efficacy, but its contribution to bone mineral density (BMD) after BP discontinuation is not known. To address this topic, we performed a retrospective analysis of postmenopausal women exposed to alendronate (ALN) to treat osteoporosis who regularly continued the supplementation of cholecalciferol or calcifediol at recommended doses. In the ninety-six recruited women (age 61.1 ± 6.9 years), ALN was administered for 31.2 ± 20.6 months and then discontinued for 33.3 ± 18.9 months. The modification of 25(OH)D serum levels over time was associated with a change of alkaline phosphatase (r = −0.22, p = 0.018) and C-terminal collagen type 1 telopeptide (r = −0.3, p = 0.06). Women in the tertile of the highest increase in 25(OH)D level showed a 5.7% BMD gain at lumbar spine, that was twice as great in comparison with participants with a lower 25(OH)D variation. At a multiple regression analysis, BMD change was associated with time since menopause (ß = 2.28, SE 0.44, p < 0.0001), FRAX score for major fracture (ß = −0.65, SE 0.29, p = 0.03), drug holiday duration (ß = −2.17, SE 0.27, p < 0.0001) and change of 25(OH)D levels (ß = 0.15, SE 0.03, p = 0.0007). After ALN discontinuation, improving the vitamin D status boosts the ALN tail effect on BMD.

Bone fragility in patients with diabetes mellitus: A consensus statement from the working group of the Italian Diabetes Society (SID), Italian Society of Endocrinology (SIE), Italian Society of Gerontology and Geriatrics (SIGG), Italian Society of Orthopaedics and Traumatology (SIOT)

Bone fragility is one of the possible complications of diabetes, either type 1 (T1D) or type 2 (T2D). Bone fragility can affect patients of different age and with different disease severity depending on type of diabetes, disease duration and the presence of other complications. Fracture risk assessment should be started at different stages in the natural history of the disease depending on the type of diabetes and other risk factors. The risk of fracture in T1D is higher than in T2D, imposing a much earlier screening and therapeutic intervention that should also take into account a patient's life expectancy, diabetes complications etc. The therapeutic armamentarium for T2D has been enriched with drugs that may influence bone metabolism, and clinicians should be aware of these effects. Considering the complexity of diabetes and osteoporosis and the range of variables that influence treatment choices in a given individual, the Working Group on bone fragility in patients with diabetes mellitus has identified and issued recommendations based on the variables that should guide screening of bone fragility and management of diabetes and bone fragility: (A)ge, (B)MD, (C)omplications, (D)uration of disease, & (F)ractures (ABCD&F). Consideration of these parameters may help clinicians identify the best time for screening, the appropriate glycaemic target and anti-osteoporosis drug for patients with diabetes at risk of or with bone fragility.

Anabolic treatments for osteoporosis in postmenopausal women

Antiresorptive agents are generally recommended as first-line treatment for osteoporosis in postmenopausal women. These drugs suppress bone resorption but do not rebuild bone, limiting their efficacy. Antiresorptive use is further hampered by concerns over rare side effects, including atypical femoral fractures and osteonecrosis of the jaw. Anabolic treatments overcome limitations of antiresorptive treatment by stimulating new bone formation, reducing the risk of fracture with greater efficacy. This review summarises the latest trial data for the three anabolic agents currently available for the treatment of osteoporosis in postmenopausal women: teriparatide, abaloparatide, and romosozumab. Data from head-to-head studies comparing anabolic and antiresorptive treatments are reviewed. At present, anabolic treatments are generally reserved for use in patients with severe osteoporosis at very high fracture risk; the factors limiting their more widespread use are discussed together with how this may change in the future.

Lumbar Scoliosis in Postmenopausal Women Increases with Age but is not Associated with Osteoporosis

CONTEXT

The contribution of lumbar scoliosis to osteoporosis is unknown.

OBJECTIVE

This work aimed to determine the prevalence and relationship of lumbar scoliosis to osteoporosis in aging women.

METHODS

A cross-sectional analysis used dual-energy x-ray absorptiometry (DXA) scans of randomly selected groups of postmenopausal women (64-68, 74-78, and 84-88 years; N = 300 each) in a university teaching hospital from 2014 to 2019. Lumbar Cobb angle was tested for an association to femoral neck (FN), total hip (TH), and spine T score, age, weight, and ethnicity. Logistic regression tested an association between scoliosis (Cobb angle > 10°) and osteoporosis (T score ≤ -2.5). Available sequential DXA scans (N = 51) were analyzed for changes in Cobb angle using a linear mixed model of these longitudinal data.

RESULTS

Osteoporosis and Cobb angle both increased with age: from 22% and 4.4 (SD = 7.8) respectively in 64- to 68-year-olds to 32.9% and to 9.7 (SD = 9.2) in women age 84 to 88 years. The prevalence of clinically significant scoliosis rose from 11.5% in the youngest group, to 27.3% and 39.4% in the age 74 to 78 and 84 to 88 cohorts, respectively. Cobb angle increased 0.7° per year of follow-up. After adjusting for covariates, there was no significant association between T scores at any site (TH, FN, or spine) and Cobb angle.

CONCLUSION

Based on screening DXAs, the incidence and degree of lumbar scoliosis increases significantly in women between age 65 and 85 years. There was no association between the incidence of lumbar scoliosis and FN bone density.

The treatment gap: The missed opportunities for osteoporosis therapy

Despite substantial advances in delineation of the epidemiology, pathophysiology, risk assessment and treatment of osteoporosis over the last three decades, a substantial proportion of men and women at high risk of fracture remain untreated - the so-called "treatment gap". This review summarises the important patient-, physician- and policyrelated causes of this treatment gap, before discussing in greater detail: (a) the evidence base for the efficacy of bisphosphonates in osteoporosis; (b) recent evidence relating to the adverse effects of this widely used therapeutic class, most notably atypical femoral fracture and osteonecrosis of the jaw; (c) available strategies to improve both secondary and primary prevention pathways for the management of this disorder.

Bisphosphonates to reduce bone fractures in stage 3B+ chronic kidney disease: a propensity score-matched cohort study

BACKGROUND

Bisphosphonates are contraindicated in patients with stage 4+ chronic kidney disease. However, they are widely used to prevent fragility fractures in stage 3 chronic kidney disease, despite a lack of good-quality data on their effects.

OBJECTIVES

The aims of each work package were as follows. Work package 1: to study the relationship between bisphosphonate use and chronic kidney disease progression. Work package 2: to study the association between using bisphosphonates and fracture risk. Work package 3: to determine the risks of hypocalcaemia, hypophosphataemia, acute kidney injury and upper gastrointestinal events associated with using bisphosphonates. Work package 4: to investigate the association between using bisphosphonates and changes in bone mineral density over time.

DESIGN

This was a new-user cohort study design with propensity score matching.

SETTING AND DATA SOURCES

Data were obtained from UK NHS primary care (Clinical Practice Research Datalink GOLD database) and linked hospital inpatient records (Hospital Episode Statistics) for work packages 1-3 and from the Danish Odense University Hospital Databases for work package 4.

PARTICIPANTS

Patients registered in the data sources who had at least one measurement of estimated glomerular filtration rate of < 45 ml/minute/1.73 m2 were eligible. A second estimated glomerular filtration rate value of < 45 ml/minute/1.73 m2 within 1 year after the first was requested for work packages 1 and 3. Patients with no Hospital Episode Statistics linkage were excluded from work packages 1-3. Patients with < 1 year of run-in data before index estimated glomerular filtration rate and previous users of anti-osteoporosis medications were excluded from work packages 1-4.

INTERVENTIONS/EXPOSURE

Bisphosphonate use, identified from primary care prescriptions (for work packages 1-3) or pharmacy dispensations (for work package 4), was the main exposure.

MAIN OUTCOME MEASURES

Work package 1: chronic kidney disease progression, defined as stage worsening or starting renal replacement. Work package 2: hip fracture. Work package 3: acute kidney injury, hypocalcaemia and hypophosphataemia identified from Hospital Episode Statistics, and gastrointestinal events identified from Clinical Practice Research Datalink or Hospital Episode Statistics. Work package 4: annualised femoral neck bone mineral density percentage change.

RESULTS

Bisphosphonate use was associated with an excess risk of chronic kidney disease progression (subdistribution hazard ratio 1.12, 95% confidence interval 1.02 to 1.24) in work package 1, but did not increase the probability of other safety outcomes in work package 3. The results from work package 2 suggested that bisphosphonate use increased fracture risk (hazard ratio 1.25, 95% confidence interval 1.13 to 1.39) for hip fractures, but sensitivity analyses suggested that this was related to unresolved confounding. Conversely, work package 4 suggested that bisphosphonates improved bone mineral density, with an average 2.65% (95% confidence interval 1.32% to 3.99%) greater gain in femoral neck bone mineral density per year in bisphosphonate users than in matched non-users.

LIMITATIONS

Confounding by indication was a concern for the clinical effectiveness (i.e. work package 2) data. Bias analyses suggested that these findings were due to inappropriate adjustment for pre-treatment risk. work packages 3 and 4 were based on small numbers of events and participants, respectively.

CONCLUSIONS

Bisphosphonates were associated with a 12% excess risk of chronic kidney disease progression in participants with stage 3B+ chronic kidney disease. No other safety concerns were identified. Bisphosphonate therapy increased bone mineral density, but the research team failed to demonstrate antifracture effectiveness.

FUTURE WORK

Randomised controlled trial data are needed to demonstrate antifracture efficacy in patients with stage 3B+ chronic kidney disease. More safety analyses are needed to characterise the renal toxicity of bisphosphonates in stage 3A chronic kidney disease, possibly using observational data.

STUDY REGISTRATION

This study is registered as EUPAS10029.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 17. See the NIHR Journals Library website for further project information. The project was also supported by the National Institute for Health Research Biomedical Research Centre, Oxford.

Treatment-Related Changes in Bone Turnover and Fracture Risk Reduction in Clinical Trials of Antiresorptive Drugs: Proportion of Treatment Effect Explained

Few analyses of antiresorptive (AR) treatment trials relate short-term changes in bone turnover markers (BTMs) to subsequent fracture reduction seeking to estimate the proportion of treatment effect explained (PTE) by BTMs. Pooling such information would be useful to assess new ARs or novel dosing regimens. In the Foundation for the National Institutes of Health (FNIH) Bone Quality project, we analyzed individual-level data from up to 62,000 participants enrolled in 12 bisphosphonate (BP) and four selective estrogen receptor modulator (SERM) placebo-controlled fracture endpoint trials. Using BTM results for two bone formation markers (bone-specific alkaline phosphatase [bone ALP] and pro-collagen I N-propeptide [PINP]) and one bone resorption marker (C-terminal telopeptide of type I collagen [CTX]) and incident fracture outcome data, we estimated the PTE using two different models. Separate analyses were performed for incident morphometric vertebral, nonvertebral, and hip fractures over 1 to 5 years of follow-up. For vertebral fracture, the results showed that changes in all three BTMs at 6 months explained a large proportion of the treatment effect of ARs (57 to >100%), but not for and non-vertebral or hip fracture. We conclude that short-term AR treatment-related changes in bone ALP, PINP, and CTX account for a large proportion of the treatment effect for vertebral fracture. Change in BTMs is a useful surrogate marker to study the anti-fracture efficacy of new AR compounds or novel dosing regiments with approved AR drugs. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

Bisphosphonates, Old Friends of Bones and New Trends in Clinics

Bisphosphonates, used for a long time in osteoporosis management, are currently the target of intensive research, from pre-formulation studies to more advanced stages of clinical practice. This review presents an overview of the contributions of this family of compounds to human health, starting with the chemistry and clinical uses of bisphosphonates. Following this, their pharmacology is described, highlighting administration-borne handicaps and undesirable effects. The last three sections of the review describe the research efforts that seek to curb delivery-related issues and expand bisphosphonate use. Innovative routes and strategies of administration, such as nano-encapsulation for oral intake or injectable cements for local or in-bone delivery are presented, as well as the latest results of case studies or preclinical studies proposing new therapeutic indications for the clinically approved bisphosphonates. Finally, a selection of anti-infectious bisphosphonate new drug candidates is shown, with focus on the molecules reported in the last two decades.

A 3-year postmarketing study on the safety and effectiveness of once-monthly risedronate in Japanese patients with osteoporosis

Objectives

This postmarketing study aims to evaluate the safety and effectiveness of oral administration of risedronate at 75 mg once monthly for 36 months in patients with osteoporosis in Japan.

Methods

Participants were ambulatory outpatients with osteoporosis who were ≥ 50 years old and had prevalent vertebral fractures. Outcomes were the incidence rate of adverse drug reaction (ADR), cumulative incidence of vertebral, nonvertebral, and hip fractures, the percent changes of lumbar spinal L_2–4 bone mineral density (BMD), and low back pain. In addition, medication compliance was examined.

Results

Safety, vertebral fractures, and other outcomes were analyzed in 542, 328, and 535 patients, respectively. In the safety analysis set, 88.38% of the patients were women and the mean age was 75.9 years. The monthly medication compliance rate ranged from 83.24% to 95.38%. The incidence rate of ADRs, including 4 severe ADRs, was 10.52% (n = 57). The common ADRs were gastrointestinal disorders, musculoskeletal, and connective tissue disorders. No osteonecrosis of the jaw was reported. The cumulative incidences (95% CI) of vertebral, nonvertebral, and hip fractures at 36 months were 12.58% (8.61–18.18), 6.59% (4.31–10.01), and 1.58% (0.64–3.88), respectively. The L_2–4 BMD increased by 10.59% compared with baseline value (P < 0.01), and the proportion of patients with low back pain decreased to 30.77%, at 36 months.

Conclusions

Administering 75 mg of risedronate once a month remains a favorable compliance rate and may be useful for the treatment of patients, even the elderly, with osteoporosis in daily practice.

Pharmacological Management of Postmenopausal Osteoporosis: a Level I Evidence Based - Expert Opinion

Objectives: Postmenopausal osteoporosis carries a high risk of fractures, which decrease quality of life and are associated with high morbidity, mortality, and economic burden. The best pharmacological treatment options to manage and prevent osteoporotic fractures remain still unclear. The present study investigated the efficacy and safety of the most commonly employed drugs in the management of postmenopausal osteoporosis. Methods: Only RCTs comparing different drugs for the management of postmenopausal osteoporosis were included. Data from 76 RCTs (205,011 patients) were collected. The mean follow-up was 27.6 ± 14.9 months. Results: Denosumab reported the lowest rate of non-vertebral fractures (LOR -1.57), Romosozumab the lowest rate of vertebral fractures (LOR 1.99), and Ibandronate the lowest rate of hip fractures (LOR0.18). Serious adverse events resulted in the lowest in the Raloxifene group (LOR 3.11), while those leading to study discontinuation were lowest in the Romosozumab cohort (LOR 2.65). Conclusions: Denosumab resulted in most effective, particularly in reducing the occurrence of non-vertebral fractures. Romosozumab and Ibandronate resulted best to prevent, respectively, vertebral fractures and hip fractures. Adverse events leading to study discontinuation were less frequent in the Romosozumab and Denosumab groups, while Raloxifene and Alendronate showed a lower incidence of serious adverse events overall. Level of evidence: I, Bayesian network meta-analysis of RCTs.

Vertebral fracture assessment (VFA) for osteoporosis screening in US postmenopausal women: is it cost-effective?

Vertebral fracture assessment (VFA) is cost-effective when it was incorporated in the routine screening for osteoporosis in community-dwelling women aged ≥ 65 years, which support guidelines, such as the National Osteoporosis Foundation (NOF) for the diagnostic use of VFA as an important addition to fracture risk assessment.

INTRODUCTION

To evaluate the cost-effectiveness of VFA as a screening tool to reduce future fracture risk in US community-dwelling women aged ≥ 65 years.

METHODS

An individual-level state-transition cost-effectiveness model from a healthcare perspective was constructed using derived data from published literature. The time horizon was lifetime. Five screening strategies were compared, including no screening at all, central dual-energy X-ray absorptiometry (DXA) only, VFA only, central DXA followed by VFA if the femoral neck T-score (FN-T) ≤ - 1.5, or if the FN-T ≤ - 1.0. Various initiation ages and rescreening intervals were evaluated. Oral bisphosphonate treatment for 5-year periods was assumed. Incremental cost-effectiveness ratios (2017 US dollars per quality-adjusted life-year (QALY) gained) were used as the outcome measure.

RESULTS

The incorporation of VFA slightly increased life expectancy by 0.1 years and reduced the number of subsequent osteoporotic fractures by 3.7% and 7.7% compared with using DXA alone and no screening, respectively, leading to approximately 30 billion dollars saved. Regardless of initiation ages and rescreening intervals, central DXA followed by VFA if the FN-T ≤ - 1.0 was most cost-effective ($40,792 per QALY when the screening is initiated at age 65 years and with rescreening every 5 years). Results were robust to change in VF incidence and medication costs.

CONCLUSION

In women aged ≥ 65 years, VFA is cost-effective when it was incorporated in routine screening for osteoporosis. Our findings support the National Osteoporosis Foundation (NOF) guidelines for the diagnostic use of VFA as an important addition to fracture risk assessment.

Bisphosphonate Treatment Beyond 5 Years and Hip Fracture Risk in Older Women

IMPORTANCE

Clinical trials have demonstrated the antifracture efficacy of bisphosphonate drugs for the first 3 to 5 years of therapy. However, the efficacy of continuing bisphosphonate for as long as 10 years is uncertain.

OBJECTIVE

To examine the association of discontinuing bisphosphonate at study entry, discontinuing at 2 years, and continuing for 5 additional years with the risk of hip fracture among women who had completed 5 years of bisphosphonate treatment at study entry.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included women who were members of Kaiser Permanente Northern and Southern California, 2 integrated health care delivery systems, and who had initiated oral bisphosphonate and completed 5 years of treatment by January 1, 2002, to September 30, 2014. Data analysis was conducted from January 2018 to August 2020.

EXPOSURE

Discontinuation of bisphosphonate at study entry (within a 6-month grace period), discontinuation at 2 years (within a 6-month grace period), and continuation for 5 additional years.

MAIN OUTCOMES AND MEASURES

The outcome was hip fracture determined by principal hospital discharge diagnoses. Demographic, clinical, and pharmacological data were ascertained from electronic health records.

RESULTS

Among 29 685 women (median [interquartile range] age, 71 [64-77] years; 17 778 [60%] non-Hispanic White individuals), 507 incident hip fractures were identified. Compared with bisphosphonate discontinuation at study entry, there were no differences in the cumulative incidence (ie, risk) of hip fracture if women remained on therapy for 2 additional years (5-year risk difference [RD], -2.2 per 1000 individuals; 95% CI, -20.3 to 15.9 per 1000 individuals) or if women continued therapy for 5 additional years (5-year RD, 3.8 per 1000 individuals; 95% CI, -7.4 to 15.0 per 1000 individuals). While 5-year differences in hip fracture risk comparing continuation for 5 additional years with discontinuation at 2 additional years were not statistically significant (5-year RD, 6.0 per 1000 individuals; 95% CI, -9.9 to 22.0 per 1000 individuals), interim hip fracture risk appeared lower if women discontinued after 2 additional years (3-year RD, 2.8 per 1000 individuals; 95% CI, 1.3 to 4.3 per 1000 individuals; 4-year RD, 9.3 per 1000 individuals; 95% CI, 6.3 to 12.3 per 1000 individuals) but not without a 6-month grace period to define discontinuation.

CONCLUSIONS AND RELEVANCE

In this study of women treated with bisphosphonate for 5 years, hip fracture risk did not differ if they discontinued treatment compared with continuing treatment for 5 additional years. If women continued for 2 additional years and then discontinued, their risk appeared lower than continuing for 5 additional years. Discontinuation at other times and fracture rates during intervening years should be further studied.

Effects of bisphosphonates on osteoporosis: Focus on zoledronate

Osteoporosis is a bone disease that mainly affects older people and postmenopausal women. Lack of proper treatment for this disease gives rise to many problems in patients and occasionally leads to death. Many drugs have been utilized to treat osteoporosis but the most effective one is the bisphosphonates (BPs) family. This family has several positive effects on bone tissue, including promoting bone healing, enhancing bone mineral density, reducing bone resorption, preventing pathologic fractures, suppressing bone turnover, and modulating bone remodeling. On the other hand, there have also been inconclusive reports that BPs might have a desirable or even adverse impact on osteoporotic patients. Therefore, we set out to examine the positive and negative effects of this family, with a focus on the most potent one that is zoledronate (Zol), in clinical usage. Zoledronate is an amino-BPs and nitrogen-containing drug which is the most powerful BPs on osteoporosis treatment or prevention. Many studies showed its effectiveness in the treatment of osteoporosis and bone healing. As Zol enjoys a considerable potential in treating and preventing osteoporosis, it can be used as one of the effective treatments in this field.

Genomic Medicine: Lessons Learned From Monogenic and Complex Bone Disorders

Current genetic studies of monogenic and complex bone diseases have broadened our understanding of disease pathophysiology, highlighting the need for medical interventions and treatments tailored to the characteristics of patients. As genomic research progresses, novel insights into the molecular mechanisms are starting to provide support to clinical decision-making; now offering ample opportunities for disease screening, diagnosis, prognosis and treatment. Drug targets holding mechanisms with genetic support are more likely to be successful. Therefore, implementing genetic information to the drug development process and a molecular redefinition of skeletal disease can help overcoming current shortcomings in pharmaceutical research, including failed attempts and appalling costs. This review summarizes the achievements of genetic studies in the bone field and their application to clinical care, illustrating the imminent advent of the genomic medicine era.

Treatment of postmenopausal osteoporosis with bone-forming and antiresorptive treatments: Combined and sequential approaches

Efficient therapies are available for the treatment of osteoporosis. Bisphosphonates and denosumab are the most commonly used antiresorptive therapies. Despite differences in the increase in bone mineral density seen with these drugs, the reductions in fracture risk are similar; 50-70%, 20%, and 40% for vertebral, non-vertebral and hip fractures, respectively. The bone-forming treatments; teriparatide and abaloparatide increase bone mineral density more than the antiresorptives and the reductions in fracture risk are 85% and 40-50% for vertebral and non-vertebral fractures, respectively, compared to placebo. The VERO study demonstrated a >50% reduction in vertebral and clinical fractures in women treated with teriparatide compared to risedronate. The dual-action treatment; romosozumab leads to more pronounced increases in BMD than other treatment modalities and reduces the risk of vertebral and clinical fractures by 73% and 36% compared to placebo after 12 months and the sequential treatment regime; romosozumab for 12 months followed by alendronate reduced the risk of vertebral, non-vertebral and hip fractures by 48%, 20% and 38%, respectively compared to alendronate after 2-3 years. The evidence for combination therapy targeting both resorption and formation is limited as only short-term studies with BMD as the endpoint have been performed. All bone-forming and dual-action treatments increase BMD and reduce the fracture risk, however, the effect wears off with time and treatment is therefore only temporary and should be followed by antiresorptive treatment with a bisphosphonate or denosumab. The sequence of treatment matters as the BMD response to teriparatide is reduced in patients previously treated with bisphosphonates; however, based on the findings of the VERO trial, the anti-fracture efficacy of bone-forming treatment in comparison with risedronate seems to be preserved after bisphosphonate therapy. The DATA study suggested that transitioning from denosumab to teriparatide is problematic due to the increase in bone resorption occurring after stopping denosumab. Studies have shown further improvements in BMD when transitioning from oral bisphosphonates to zoledronic acid or denosumab. Management of osteoporosis will in many patients include a long-term treatment plan. This will often include sequential therapy which in severe cases preferably should start with bone-forming followed by antiresorptive treatment. The severity of osteoporosis, reaching a treatment goal, and responding to treatment failure are important factors determining the treatment sequence in the individual patient.

The top 100 highly cited articles on osteoporosis from 1990 to 2019: a bibliometric and visualized analysis

Research on osteoporosis is a well-developed and promising research field. The top 100 literature included 73 articles and 27 reviews. The average citation number was 747 (range 370 to 2970). Researchers and institutions from the USA, the UK, and France contributed the most to the top high-cited articles.

PURPOSE

To provide a bibliometric and visualized analysis of the top 100 highly cited articles on osteoporosis indexed by the Web of Science (WoS) from 1990 to 2019.

METHODS

Data were obtained from the WoS Core Collection on Jan 10, 2020. Qualitative and quantitative analysis was conducted based on WoS. Collaboration analysis and keywords analysis were performed using VosView software.

RESULTS

A total of 12,863 references were obtained. The top 100 highly cited literature included 73 articles and 27 reviews. The average citation number of the 100 articles was 747 (range 370 to 2970). The fund sources mostly came from the USA. A total of 29 journals published the top 100 highly cited literature. The New England Journal of Medicine had the largest number of papers and the highest total cited times. The USA published 72 articles. The University of California San Francisco published 17 articles, followed by University of Sheffield and Mayo Clinic and Mayo Foundation. Cooper C had the most publications (n = 12) and Genant HK had the largest total citation (n = 11,055). Considering only the first author and corresponding author, Kanis JA had published the most articles. Researchers and institutions from the USA, the UK, and France contributed the most to the top high-cited articles.

CONCLUSIONS

Research on osteoporosis is a well-developed and promising research field. The top 100 articles have been cited widely and actively. New England Journal of Medicine was the most popular journal. The most productive country was the USA. The University of California San Francisco, University of Sheffield, and Mayo Clinic and Mayo Foundation were the most productive institutions. Cooper C, Kanis JA, and Genant HK were the most prolific and influential authors. Researchers and institutions from North America and Europe contributed the most.

Autonomy begets adherence: decisions to start and persist with osteoporosis treatment after group medical consultation

Many individuals prescribed osteoporosis pharmacotherapy either do not start or do not persist with treatment. In this study, women who attended a group medical visit at an osteoporosis center which involved fracture risk assessment and focused on autonomous decision-making made treatment decisions with high confidence. Those who started pharmacotherapy were highly persistent.

PURPOSE

Adherence and persistence with osteoporosis pharmacotherapy is low, possibly reflecting lack of confidence in physicians' treatment recommendations. We evaluated treatment decisions, decisional confidence, and 12-month treatment adherence among women who attended a group bone health consultation that fostered autonomous decision-making.

METHODS

We prospectively assessed postmenopausal women referred to an osteoporosis clinic who chose to attend a group medical visit in lieu of one-on-one consultation. The group visit was facilitated by a specialist physician and nurse, involving estimation of 10-year major osteoporotic fracture risk (using FRAX®) and extensive education regarding fracture consequences and potential advantages and disadvantages of pharmacotherapy. No direct advice was given by the specialist. Post-consult, participants made an autonomous decision regarding treatment intent and followed up with their family physician to enact their chosen plan. Intentions to initiate pharmacotherapy were assessed immediately post-consult. Treatment status and decisional confidence were evaluated 3 and 12 months later. Three-month treatment status was considered to reflect final treatment decision. Persistence was defined as proportion of participants on treatment at 3 months who remained treated at 12 months.

RESULTS

One hundred one women (mean (SD) age, 62.7 years (5.8); median (IQR) FRAX®, 10.7% (8.3-17.6)) participated. Immediately post-consult, 27 (26.7%) intended to initiate treatment. At 3 months, 23 (22.8%) were treated, and at 12 months, 21 (91.3%) remained persistent. Of 89 questionnaire respondents at 12 months, 85 (95.5%) reported confidence in their treatment decision.

CONCLUSION

When postmenopausal women are provided with individualized fracture risk estimates and enabled to make autonomous decisions regarding pharmacotherapy, ultimate decisions to receive treatment are made with confidence and result in high persistence at 12 months.

Bisphosphonates and parathyroid hormone analogs for improving bone quality in spinal fusion: State of evidence

Spinal fusion is among the most commonly performed surgical procedures for elderly patients with spinal disorders - including degenerative disc disease with spondylolisthesis, deformities, and trauma. With the large increase in the aging population and the prevalence of osteoporosis, the number of elderly osteoporotic patients needing spinal fusion has risen dramatically. Due to reduced bone quality, postoperative complications such as implant failures, fractures, post-junctional kyphosis, and pseudarthrosis are more commonly seen after spinal fusion in osteoporotic patients. Therefore, pharmacologic treatment strategies to improve bone quality are commonly pursued in osteoporotic cases before conducting spinal fusions. The two most commonly used pharmacotherapeutics are bisphosphonates and parathyroid hormone (PTH) analogs. Evidence indicates that using bisphosphonates and PTH analogs, alone or in combination, in osteoporotic patients undergoing spinal fusion, decreases complication rates and improves clinical outcomes. Further studies are needed to develop guidelines for the administration of bisphosphonates and PTH analogs in osteoporotic spinal fusion patients in terms of treatment duration, potential benefits of sequential use, and the selection of either therapeutic agents based on patient characteristics.

Controversies in the treatment of postmenopausal osteoporosis: How long to treat with bisphosphonates?

Osteoporosis is a systemic skeletal disease characterized by reduced bone mass and deterioration of bone tissue microarchitecture leading to an increased risk of fractures. Fragility fractures, especially hip fractures, are associated with a significant reduction in the physical function and quality of life of affected patients, as well as increased mortality, leading to a major financial impact on health care. Many drugs have been registered for the treatment of osteoporosis and very recently, a new anabolic agent, romosozumab, has been approved in some countries. Despite the expansion of efficacious antiresorptive and anabolic therapies in recent years, a concomitant increase in concerns have been raised by physicians, patients and the lay press about the potential for adverse events, especially atypical femoral fractures (AFF) following prolonged use of bisphosphonates. Whatever the mechanism(s) may be, direct or indirect, linking prolonged bisphosphonate use to atypical femoral fractures, this adverse event is very rare in comparison to the magnitude of risk reduction of typical osteoporotic fractures. An estimated 162 osteoporosis-related fractures are prevented for each atypical femoral fracture associated with an anti-resorptive medication. Until a risk calculator for predicting risk of atypical fractures, becomes available in clinical practice, and we view this as an unlikely scenario, it is up to the physician to consider continuing or discontinuing bisphosphonate use after the critical 3-5 year period of treatment with zoledronic acid or alendronate, but close monitoring for the residual bone effects overtime should be planned. For other bisphosphonates, in which no residual effects are expected, drug holiday is usually not applied.

Treatment-related changes in bone mineral density as a surrogate biomarker for fracture risk reduction: meta-regression analyses of individual patient data from multiple randomised controlled trials

BACKGROUND

The validation of bone mineral density (BMD) as a surrogate outcome for fracture would allow the size of future randomised controlled osteoporosis registration trials to be reduced. We aimed to determine the association between treatment-related changes in BMD, assessed by dual-energy x-ray absorptiometry, and fracture outcomes, including the proportion of treatment effect explained by BMD changes.

METHODS

We did a pooled analysis of individual patient data from multiple randomised placebo-controlled clinical trials. We included data from multicentre, randomised, placebo-controlled, double-blind trials of osteoporosis medications that included women and men at increased osteoporotic fracture risk. Using individual patient data for each trial we calculated mean 24-month BMD percent change together with fracture reductions and did a meta-regression of the association between treatment-related differences in BMD changes (percentage difference, active minus placebo) and fracture risk reduction. We also used individual patient data to determine the proportion of anti-fracture treatment effect explained by BMD changes and the BMD change needed in future trials to ensure fracture reduction efficacy.

FINDINGS

Individual patient data from 91 779 participants of 23 randomised, placebo-controlled trials were included. The trials had 1-9 years of follow-up and included 12 trials of bisphosphonate, one of odanacatib, two of hormone therapy (one of conjugated equine oestrogen and one of conjugated equine oestrogen plus medroxyprogesterone acetate), three of PTH receptor agonists, one of denosumab, and four of selective oestrogen receptor modulator trials. The meta-regression revealed significant associations between treatment-related changes in hip, femoral neck, and spine BMD and reductions in vertebral (r2 0·73, p<0·0001; 0·59, p=0·0005; 0·61, p=0·0003), hip (0·41, p=0·014; 0·41, p=0·0074; 0·34, p=0·023) and non-vertebral fractures (0·53, p=0·0021; 0·65, p<0·0001; 0·51, p=0·0019). Minimum 24-month percentage changes in total hip BMD providing almost certain fracture reductions in future trials ranged from 1·42% to 3·18%, depending on fracture site. Hip BMD changes explained substantial proportions (44-67%) of treatment-related fracture risk reduction.

INTERPRETATION

Treatment-related BMD changes are strongly associated with fracture reductions across randomised trials of osteoporosis therapies with differing mechanisms of action. These analyses support BMD as a surrogate outcome for fracture outcomes in future randomised trials of new osteoporosis therapies and provide an important demonstration of the value of public access to individual patient data from multiple trials.

FUNDING

Foundation for National Institutes of Health.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS/AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS-2020 UPDATE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs). Methods: Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2020 updated guideline contains 52 recommendations: 21 Grade A (40%), 24 Grade B (46%), 7 Grade C (14%), and no Grade D (0%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 368 citations: 123 (33.5%) evidence level (EL) 1 (highest), 132 (36%) EL 2 (intermediate), 20 (5.5%) EL 3 (weak), and 93 (25%) EL 4 (lowest). New or updated topics in this CPG include: clarification of the diagnosis of osteoporosis, stratification of the patient according to high-risk and very-high-risk features, a new dual-action therapy option, and transitions from therapeutic options. Conclusion: This guideline is a practical tool for endocrinologists, physicians in general, regulatory bodies, health-related organizations, and interested laypersons regarding the diagnosis, evaluation, and treatment of post-menopausal osteoporosis. Abbreviations: 25(OH)D = 25-hydroxyvitamin D; AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AFF = atypical femoral fracture; ASBMR = American Society for Bone and Mineral Research; BEL = best evidence level; BMD = bone mineral density; BTM = bone turnover marker; CI = confidence interval; CPG = clinical practice guideline; CTX = C-terminal telopeptide type-I collagen; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = U.S. Food and Drug Administration; FRAX® = Fracture Risk Assessment Tool; GI = gastrointestinal; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic acid ONce yearly Pivotal Fracture Trial (zoledronic acid and zoledronate are equivalent terms); ISCD = International Society for Clinical Densitometry; IU = international units; IV = intravenous; LSC = least significant change; NOF = National Osteoporosis Foundation; ONJ = osteonecrosis of the jaw; PINP = serum amino-terminal propeptide of type-I collagen; PTH = parathyroid hormone; R = recommendation; ROI = region of interest; RR = relative risk; SD = standard deviation; TBS = trabecular bone score; VFA = vertebral fracture assessment; WHO = World Health Organization.

Practical guidance for the use of bisphosphonates in osteoporosis

Bisphosphonates are widely used in the treatment of osteoporosis in postmenopausal women and older men. In clinical trials they have been shown to reduce fractures in women with osteoporosis and there is increasing evidence that they are also effective in women with osteopenia, in whom the majority of fractures occur. In addition to their role as initial therapy in individuals at increased risk of fracture, bisphosphonates are used as sequential therapy after treatment with anabolic drugs. There are no head-to head studies to compare the anti-fracture efficacy of different bisphosphonates, but there is limited evidence that zoledronate treatment results in greater increases in BMD than risedronate or alendronate. This, together with the need for less frequent administration of zoledronate, supports its wider use in clinical practice, particularly if longer dosing intervals than those currently recommended are shown to be effective.

Pharmacological treatment for managing bone health in axial spondyloarthropathy: systematic review and meta-analysis

Axial spondyloarthropathy (axSpA) is associated with an increased prevalence of osteoporosis, but no recommendations exist to guide management. This systematic review and meta-analysis aim to assess the efficacy of pharmacological and non-pharmacological interventions on bone mineral density (BMD) in axSpA. Electronic databases were searched from inception to June 2019 for randomised controlled trials (RCTs) and quasi (q)-RCTs with pharmacological and non-pharmacological interventions. Independent reviewers undertook screening, and risk of bias and quality assessments. Primary outcomes of interest were BMD at spine and hip. Eight studies (two RCTs and six qRCTs) were included (602 participants). Moderate level evidence favoured alendronate over placebo at femoral neck [mean difference (MD) 2.01, 95% CI 0.67 to 3.35], but there was low-level evidence showing no effect at the spine. There was moderate level evidence showing no effect of tumour necrosis factor inhibitors (TNFi) on BMD at total hip (MD - 0.01, 95% CI - 0.06 to 0.04). Very low-level evidence demonstrated no effect of TNFi on spine or femoral neck. Moderate level evidence favoured neridronate over infliximab at the spine (MD 3.26, 95% CI 1.14 to 5.38), but low-level evidence showed no effect at the total hip (MD 2.75, 95% CI - 0.21 to 5.71). There were no eligible studies investigating the efficacy of non-pharmacological interventions. We conditionally recommend alendronate for management of low BMD in axSpA. The balance of evidence does not recommend the use of TNF-inhibitors for treating low BMD. There is a lack of high-quality evidence guiding clinicians treating osteoporosis in axSpA.

Denosumab, raloxifene, romosozumab and teriparatide to prevent osteoporotic fragility fractures: a systematic review and economic evaluation

BACKGROUND

Fragility fractures are fractures that result from mechanical forces that would not ordinarily result in fracture.

OBJECTIVES

The objectives were to evaluate the clinical effectiveness, safety and cost-effectiveness of non-bisphosphonates {denosumab [Prolia®; Amgen Inc., Thousand Oaks, CA, USA], raloxifene [Evista®; Daiichi Sankyo Company, Ltd, Tokyo, Japan], romosozumab [Evenity®; Union Chimique Belge (UCB) S.A. (Brussels, Belgium) and Amgen Inc.] and teriparatide [Forsteo®; Eli Lilly and Company, Indianapolis, IN, USA]}, compared with each other, bisphosphonates or no treatment, for the prevention of fragility fracture.

DATA SOURCES

For the clinical effectiveness review, nine electronic databases (including MEDLINE, EMBASE and the World Health Organization International Clinical Trials Registry Platform) were searched up to July 2018.

REVIEW METHODS

A systematic review and network meta-analysis of fracture and femoral neck bone mineral density were conducted. A review of published economic analyses was undertaken and a model previously used to evaluate bisphosphonates was adapted. Discrete event simulation was used to estimate lifetime costs and quality-adjusted life-years for a simulated cohort of patients with heterogeneous characteristics. This was done for each non-bisphosphonate treatment, a strategy of no treatment, and the five bisphosphonate treatments previously evaluated. The model was populated with effectiveness evidence from the systematic review and network meta-analysis. All other parameters were estimated from published sources. An NHS and Personal Social Services perspective was taken, and costs and benefits were discounted at 3.5% per annum. Fracture risk was estimated from patient characteristics using the QFracture® (QFracture-2012 open source revision 38, Clinrisk Ltd, Leeds, UK) and FRAX® (web version 3.9, University of Sheffield, Sheffield, UK) tools. The relationship between fracture risk and incremental net monetary benefit was estimated using non-parametric regression. A probabilistic sensitivity analysis and scenario analyses were used to assess uncertainty.

RESULTS

Fifty-two randomised controlled trials of non-bisphosphonates were included in the clinical effectiveness systematic review and an additional 51 randomised controlled trials of bisphosphonates were included in the network meta-analysis. All treatments had beneficial effects compared with placebo for vertebral, non-vertebral and hip fractures, with hazard ratios varying from 0.23 to 0.94, depending on treatment and fracture type. The effects on vertebral fractures and the percentage change in bone mineral density were statistically significant for all treatments. The rate of serious adverse events varied across trials (0-33%), with most between-group differences not being statistically significant for comparisons with placebo/no active treatment, non-bisphosphonates or bisphosphonates. The incremental cost-effectiveness ratios were > £20,000 per quality-adjusted life-year for all non-bisphosphonate interventions compared with no treatment across the range of QFracture and FRAX scores expected in the population eligible for fracture risk assessment. The incremental cost-effectiveness ratio for denosumab may fall below £30,000 per quality-adjusted life-year at very high levels of risk or for high-risk patients with specific characteristics. Raloxifene was dominated by no treatment (resulted in fewer quality-adjusted life-years) in most risk categories.

LIMITATIONS

The incremental cost-effectiveness ratios are uncertain for very high-risk patients.

CONCLUSIONS

Non-bisphosphonates are effective in preventing fragility fractures, but the incremental cost-effectiveness ratios are generally greater than the commonly applied threshold of £20,000-30,000 per quality-adjusted life-year.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42018107651.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 29. See the NIHR Journals Library website for further project information.

Primary osteoporosis in men: an unmet medical need

Osteoporosis is a skeletal disease characterized by loss of bone strength and increased risk of fractures. Even though fracture prevalence is higher in women, fractures also constitute a significant public health issue in older men. Men are screened less and more frequently undertreated than female patients. It is the goal of this review, to summarize updated information about the current understanding of pathophysiology and clinical aspects of diagnosis and treatment of osteoporosis in men.

Effects of the combined administration of risedronate and menatetrenone on bone loss induced by tacrolimus in rats

Tacrolimus, a calcineurin inhibitor, affects bone metabolism and increases the risk of fracture due to marked bone loss. Bisphosphonates increase the bone mineral density (BMD) in osteoporosis patients. Menatetrenone has less positive effects on BMD but reduces the risk of fracture by improving bone quality. In this study, we investigated the effectiveness of the combined administration of risedronate and menatetrenone against bone loss induced by tacrolimus. Wistar rats were divided into four groups: [1] control, [2] tacrolimus at 1.5 mg/kg, [3] tacrolimus + risedronate at 1.0 mg/kg, and [4] tacrolimus + risedronate + menatetrenone at 20 mg/kg. After the drugs were administered for 4 weeks, bone histomorphometric analysis was performed and bone strength was evaluated using a three point bending method. BMD was measured using quantitative computed tomography. Tacrolimus significantly reduced the BMD and strength properties of the lower limb bones. These tacrolimusinduced decreases were suppressed by risedronate treatment. The combined administration of risedronate and menatetrenone more significantly improved bone strength properties than risedronate alone. Bone histomorphometric analysis revealed a significant increase in bone resorption with tacrolimus. Risedronate alone significantly suppressed the tacrolimus-induced increase in bone resorption but simultaneously reduced bone formation. On the other hand, the combined administration of risedronate and menatetrenone suppressed the tacrolimus-induced increase in bone resorption, in addition to the significant risedronate-induced decrease in bone formation. This study suggests that the combined administration of risedronate and menatetrenone improves bone strength in tacrolimus-treated rats by preventing and ameliorating the risedronate-induced suppression of bone formation.

A Mixed Methods Study Exploring Older Womens' Attitudes Toward Osteoporosis Medications: Adapting a Health Communication Framework

Background: Bisphosphonates (BPs) can reduce fracture risk for adults with osteoporosis (OP), but they have rare risks, complicating decision making. Guided by an established health decision and communication framework, we explored older women's feelings and positions toward taking BPs. Materials and Methods: Using a mixed-methods design, we interviewed women >65 years of age who had never taken BPs. After learning about BPs, participants responded to items about their feelings toward medication benefits/risks. They then identified their overall position toward taking BPs (corresponding to Unquestioning Acceptors, Cautious Acceptors, Hesitants, Probable Refusers, and Definite Refusers). We analyzed data using qualitative content analysis and summarized quantitative data with descriptive statistics. Results: Thirty women participated. Acceptors (N = 17, 56.6%) worried about OP-related fractures. Hesitant participants (N = 12, 40%) worried about BP risks, yet expressed openness toward medications if given opportunities to gather information and talk to clinicians. One Refuser expressed distrust in clinicians and pharmaceuticals. Conclusions: Understanding women's positions toward BPs might improve decision-making processes for OP treatment. Clinicians could tailor communication based on patients' identified BP position. Acceptors might be comfortable with succinct conversations describing medications. Hesitant patients might need more information from resources such as decision aids. Building trust with patients questioning BPs can support future conversations.

Adjuvant drug-assisted bone healing: Part III - Further strategies for local and systemic modulation

In this third in a series of reviews on adjuvant drug-assisted bone healing, further approaches aiming at influencing the healing process are discussed. Local and systemic modulation of bone metabolism is pursued with use of a number of drugs with completely different indications, which are characterized by a pleiotropic spectrum of action. These include drugs used to treat lipid disorders (HMG-CoA reductase inhibitors), hypertension (ACE inhibitors), osteoporosis (bisphosphonates), cancer (proteasome inhibitors) and others. Potential applications to enhance bone healing are discussed.

Overview of treatment approaches to osteoporosis

Efficient therapies are available for the treatment of osteoporosis. Anti-resorptive therapies, including bisphosphonates and denosumab, increase bone mineral density (BMD) and reduce the risk of fractures by 20-70%. Bone-forming or dual-action treatments stimulate bone formation and increase BMD more than the anti-resorptive therapies. Two studies have demonstrated that these treatments are superior to anti-resorptives in preventing fractures in patients with severe osteoporosis. Bone-forming or dual-action treatments should be followed by anti-resorptive treatment to maintain the fracture risk reduction. The BMD gains seen with bone-forming and dual-action treatments are greater in treatment-naïve patients compared to patients pretreated with anti-resorptive treatments. However, the antifracture efficacy seems to be preserved. Treatment failure will often lead to switch of treatment from orally to parentally administrated anti-resorptives treatment or from anti-resorptive to bone-forming or dual-action treatment. Osteoporosis is a chronic condition and therefore needs a long-term management plan with a personalized approach to treatment. LINKED ARTICLES: This article is part of a themed issue on The molecular pharmacology of bone and cancer-related bone diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.9/issuetoc.

Vitamin D supplementation: much ado about nothing

The scientific interest and the number of papers dealing with vitamin D supplementation has greatly grown in the last decades. Unfortunately, expert consensus on many clinical aspects of this topic is still lacking. In addition, data coming from recent clinical trials and meta-analyses seem to strongly put into doubt the real benefit of vitamin D supplementation, on both skeletal and extra-skeletal outcomes. This is further confusing since they seem to completely contradict the considerable body of evidence provided from previous epidemiological studies. This paper aims to analyze these new data in order to shed light onto the debated issues.

Osteoporosis and fragility fractures: risk assessment, management and prevention

Osteoporosis is a chronic skeletal condition characterised by low bone mass and microarchitectural deterioration of the bones that disproportionately affects older people. Older people with osteoporosis are at increased risk of sustaining fragility fractures, and this risk is compounded by factors such as falls and frailty. Fragility fractures can have several physical and psychological effects, potentially affecting an older person's quality of life and reducing their life expectancy. Therefore, it is important that nurses can identify individuals at risk of osteoporosis and recognise the factors that may predict fragility fractures. This article outlines the main risk factors for osteoporosis and details the assessment and management of patients with this condition. It also explains the pharmacological interventions and lifestyle changes that can reduce the risk of fragility fractures in older people with osteoporosis.

Oral Treatment With Bisphosphonates of Osteoporosis Does Not Increase the Risk of Severe Gastrointestinal Side Effects: A Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Bisphosphonates (BPs) are first-line therapy for osteoporosis. Adherence is usually low in chronic, asymptomatic diseases, but gastrointestinal (GI) side-effects can also contribute to low adherence in BP therapy and may necessitate a review by a gastroenterologist with or without gastroscopy.

AIMS

Our meta-analysis aims to determine the risk of severe GI adverse events due to oral BP therapy in osteoporotic patients.

METHODS

A systematic search was conducted in three databases up to September 2020 for randomized controlled trials (RCTs) detailing GI adverse events in adults with osteoporosis on BP compared to placebo. Risk ratios (RRs) with 95% confidence intervals (CI) were calculated for non-severe and severe adverse events indicating endoscopic procedure with the random-effects model. Statistical heterogeneity was assessed using chi² and I² statistics.

RESULTS

Forty-two RCTs with 39,047 patients with 9,999 non-severe and 1,503 severe GI adverse events were included. The incidence of non-severe and severe adverse events ranged between 0.3-54.9 and 0-10.3%, respectively. There was no difference between BP and control groups in terms of the risk of non-severe or severe side effects: RR=1.05 (CI: 0.98-1.12), I² = 48.1%, and RR=1.01 (CI: 0.92-1.12), I² = 0.0%, respectively. Subgroup analysis of the most commonly used BP, once-weekly alendronate 70 mg, revealed an association between bisphosphonates and the risk of non-severe GI adverse events, RR=1.16 (CI: 1.00-1.36), I² = 40.7%, while the risk of severe GI side effects was not increased in this subgroup, RR=1.20 (CI: 0.83-1.74), I² = 0.0%.

CONCLUSION

Our results show that bisphosphonates do not increase the risk of severe GI adverse events. However, the marked variability of the screening for side effects in the included studies, and the fact that in most of the studies GI diseases were exclusion criteria limits the strenght of evidence of our results. The conclusions drawn from the meta-analysis are therefore restricted to selected populations, and the results must be interpreted with caution.

Bisphosphonates for Secondary Prevention of Osteoporotic Fractures: A Bayesian Network Meta-Analysis of Randomized Controlled Trials

Purpose

To investigate the comparative efficacies of the five most commonly used bisphosphonates for the secondary prevention of osteoporotic fractures in a Bayesian network meta-analysis.

Methods

Five databases and the reference lists of all acquired articles from inception to July 2017 were searched. A Bayesian random-effects model was employed, and vertebral, hip and nonvertebral nonhip fractures were assessed by odds ratios (ORs) and 95%credible intervals. Furthermore, with respect to each endpoint, rank probabilities for each bisphosphonate were evaluated using the surface under the cumulative ranking curve (SUCRA) value.

Results

Thirteen eligible studies were identified involving 11,822 patients with osteoporotic fractures. Overall in the pairwise meta-analyses, bisphosphonate use significantly reduced the risk of new vertebral, hip, and nonvertebral nonhip fractures, with ORs and 95% confidence intervals of 0.56 (0.49–0.64), 0.69 (0.48–0.98), and 0.82 (0.70–0.97), respectively. In network meta-analyses, significant differences were found between placebo and any one of the five bisphosphonates for new vertebral fractures. The rank probability plot and the SUCRA calculation results suggested that alendronate was the best intervention (14.6%) for secondary prevention of vertebral fractures, followed by zoledronate (15.3%) and etidronate (22.1%). In terms of the incidence of new hip fractures, alendronate was associated with the lowest incidence (18.5%), followed by zoledronate (43.1%) and risedronate (52.5%). However, zoledronate ranked lowest (16.6%) regarding the incidence of new nonvertebral nonhip fractures, followed by risedronate (23.8%) and alendronate (44.1%).

Conclusions

Bisphosphonates show significant efficacy for secondary prevention of new vertebral fractures, and alendronate is most likely to be successful at secondary prevention of vertebral and hip fractures compared with the other four bisphosphonates.

Association Between Drug Treatments for Patients With Osteoporosis and Overall Mortality Rates: A Meta-analysis

IMPORTANCE

Previous studies have reported that drug treatments, particularly treatment with bisphosphonates, is associated with reduced overall mortality rates in addition to decreased fracture risk. If so, drug treatments should be recommended for this reason alone, regardless of a patient's risk of fracture.

OBJECTIVE

To assess whether randomized clinical trials demonstrate that treatment with bisphosphonates, particularly zoledronate, is associated with reduced mortality rates.

DATA SOURCES

Science Direct, MEDLINE, Embase, and the Cochrane Library were searched for randomized placebo-controlled clinical trials of drug treatments for osteoporosis published after 2009 and published or in press before April 19, 2019. Conference abstracts from annual osteoporosis society meetings were also included in the search.

STUDY SELECTION

Included studies were clinical trials that (1) were randomized and placebo-controlled; (2) studied drug treatments with proven antifracture efficacy; (3) used agents at the approved dose for treatment of osteoporosis; and (4) had a duration of 1 year or more. Abstracts from the literature searches were reviewed for inclusion and exclusion criteria, and mortality rate data were abstracted from the article by 1 researcher and validated by a second. A total of 2045 records were screened; 38 (1.8%) were included in the meta-analyses.

DATA EXTRACTION AND SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist was followed for abstracting data and assessing data quality and validity. Data were pooled using random-effects models, and between-study variability was assessed using the I2 index. The risk of bias for each study was assessed, and funnel plots and Egger and Begg statistics were used to evaluate publication bias.

MAIN OUTCOMES AND MEASURES

Associations of all drug treatments, particularly bisphosphonate and zoledronate treatments, with overall mortality.

RESULTS

Of 38 clinical trials that included 101 642 unique participants, 38 were included in the meta-analyses of all drug treatments (45 594 participants randomized to placebo; 56 048 to treatment); 21 clinical trials, of bisphosphonate treatments (20 244 participants randomized to placebo; 22 623 to treatment); and 6 clinical trials, of zoledronate treatments (6944 participants randomized to placebo; 6926 to treatment). No significant association was found between all drug treatments for osteoporosis and overall mortality rate (risk ratio [RR], 0.98; 95% CI, 0.91-1.05; I2 = 0%). Clinical trials of bisphosphonate treatment (RR, 0.95; 95% CI, 0.86-1.04) showed no significant association with overall mortality. Also, clinical trials of zoledronate treatment (RR, 0.88; 95% CI, 0.68-1.13) showed no association with overall mortality rate; however, evidence existed for heterogeneity of the results (I2 = 48.2%).

CONCLUSIONS AND RELEVANCE

Results of this meta-analysis suggest that bisphosphonate treatment may not be associated with reduced overall mortality rates in addition to decreased fracture risk and should only be recommended to reduce fracture risk. Additional trials are needed to clarify whether treatment with zoledronate reduces mortality rates.