Alendronate and atrial fibrillation: a meta-analysis of randomized placebo-controlled clinical trials

Antiosteoporosis medications and cardiovascular disease: a population-based nationwide nested case-control study

Purpose: Patients with osteoporosis are at an increased risk of cardiovascular disease (CVD). Several antiosteoporosis medications have been demonstrated with the benefit of preventing osteoporosis. Our aim is to assess the CVD risks associated with antiosteoporosis medications using the National Health Insurance Research Database in Taiwan between 2000 and 2016. Methods: Among 41,102 patients of 40+ years old with newly diagnosed osteoporosis, 69.1% (N = 28,387) of patients were included in the user cohort of antiosteoporosis medicines, of whom 13, 472 developed CVD by the end of 2016, while 14,915 did not. Using the nested case-control analysis in the user cohort (88.0% women and 77.4% elderly), we applied conditional logistic regression to estimate odds ratios (ORs) of eight types of CVD for the users of denosumab, bisphosphonate, teriparatide, and hormone replacement therapy (HRT). Results: The adjusted ORs of overall CVDs were 0.13 (95% CI: 0.12-0.15) for denosumab users, 0.52 (95% CI: 0.45-0.61) for teriparatide users, and 0.80 (95% CI: 0.76-0.85) for bisphosphonate users. The HRT users were at higher odds of coronary artery and peripheral artery diseases, heart failure, pulmonary embolism, and deep vein thrombosis. Conclusion: Denosumab, teriparatide, and bisphosphonate may have more protective effects against CVD than hormone therapy. Physicians may take subsequent cardiovascular risks into account when choosing an adequate antiosteoporosis medication for patients with osteoporosis.

Cardiac adverse events in bisphosphonate and teriparatide users: An international pharmacovigilance study

BACKGROUND

Cardiovascular effects of osteoporosis medications have recently been highlighted. Although oral and intravenous bisphosphonates are assumed to have similar cardiovascular safety, few head-to-head comparisons exist. The cardiovascular safety of teriparatide is unknown. Aim We conducted a pharmacovigilance safety study of cardiac events using real-life adverse event reports from alendronate, zoledronic acid and teriparatide users.

METHODS

Adverse drug reactions were obtained from Vigibase, a WHO database of individual case safety reports (ICSRs) from 130 countries (1967-2020). ISCRs for atrial fibrillation (AF), angina pectoris, arteriosclerosis coronary artery (ACA), cardiac arrhythmias, coronary artery disease (CAD), thromboembolic events (TE), ischaemic heart disease (IHD), torsade de pointes/QT prolongation (TDP) associated with alendronate, zoledronic acid and teriparatide use were extracted. Data were included in a disproportionality analysis where the lower end of the 95 % credibility interval for the information component (IC₀₂₅), showing a statistical association when >0. Head-to-head comparisons of ISCRs were estimated by age-adjusted odds ratios and 95 % confidence intervals.

RESULTS

465 episodes of angina, 287 ACA, 13,385 arrhythmias, 792 CAD, 6743 TE, 3264 IHD, 1037 myocardial infarcts, and 3714 TDP events were recorded across 50,365 alendronate, 52,436 zoledronic acid and 137,629 teriparatide users. There was a significant association between alendronate and zoledronate with all outcomes except MI. Teriparatide use was associated with AF, arrythmias and angina only. In head-to-head comparisons, teriparatide use was associated with fewer ACA and CAD events than alendronate and fewer ACA than zoledronic acid.

DISCUSSION

Osteoporosis medication use is associated with adverse cardiac events, except for MI, and these appear to be more common with oral and intravenous bisphosphonates than teriparatide. Our data do not support differential effects of oral and intravenous bisphosphonates on cardiac events. Mechanisms whereby teriparatide may be cardio-protective warrant further investigation.

Cardiovascular benefits and risks associated with calcium, vitamin D, and antiresorptive therapy in the management of skeletal fragility

Osteoporosis affects one in every five women over the age of 50 worldwide. With a rapidly ageing population, the prevalence of fragility fractures, considered a largely preventable consequence of osteoporosis, is expected to increase. Age is also a major risk for cardiovascular disease and mortality, thus highlighting the importance of cardiovascular profiling of osteoporosis interventions. Although calcium and vitamin D are essential for a healthy bone metabolism, excessive supplementation may be associated with increased risk. Conversely, early pre-clinical data have suggested a possible cardiovascular benefit from bisphosphonate therapy. This review evaluates the evidence behind the cardiovascular benefits and risks that may be associated with osteoporosis therapy.

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.

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.

Cardiovascular Safety of Denosumab Across Multiple Indications: A Systematic Review and Meta-Analysis of Randomized Trials

The cardiovascular safety of denosumab has not yet been evaluated in a systematic review. This systematic review and meta-analysis sought to quantify the number of randomized controlled trials (RCTs) of denosumab (against comparators) reporting cardiovascular adverse events (CAEs) and examine the balance of CAEs between treatment arms. MEDLINE, Embase, and clinicaltrials.gov were searched from inception to October 26, 2019, for RCTs of denosumab versus comparators for any indication. Included trials were randomized, enrolled ≥100 participants, and reported bone-related outcomes. Primary outcome for analysis was all CAEs, a composite endpoint representing summation of all CAEs as reported by included trials. Secondary outcomes included major adverse cardiovascular events (MACE). Data were pooled using a fixed effects model to determine relative risk (RR) and 95% confidence interval (95% CI). Risk of bias was assessed using the Cochrane risk-of-bias tool. Of 554 records screened, 49 were included, while 36 reported CAEs. Twenty-seven included trials (12 eligible for meta-analysis) were conducted in 13,202 postmenopausal women. Compared with bisphosphonates, there was a 46% (95% CI 1.05 to 2.02) increase in CAEs (85/2136 events in denosumab-treated versus 58/2131 events in bisphosphonate-treated; seven trials). There was a similar imbalance in a five-point (stroke, myocardial infarction, cardiovascular death, heart failure, atrial fibrillation) MACE endpoint (28/2053 versus 12/2050; RR = 2.33 [1.19 to 4.56]). Compared with placebo-treated women, there was no imbalance in total CAEs (439/4725 events in denosumab versus 399/4467 in placebo; RR = 0.79 [0.41 to 1.52]; seven trials). No imbalance in total AEs (versus bisphosphonates: 0.98 [0.92 to 1.04]; versus placebo: 0.99 [0.98 to 1.01]) occurred. Other indications showed no statistically significant results. The excess CAEs in postmenopausal women treated with denosumab compared with bisphosphonates, but not placebo, indirectly supports claims that bisphosphonates may suppress CAEs. Future trials should use standardized CAE reporting to better describe cardiovascular effects of bone active medications. (PROSPERO: CRD42019135414.) © 2020 American Society for Bone and Mineral Research (ASBMR).

The Belgian Bone Club 2020 guidelines for the management of osteoporosis in postmenopausal women

PURPOSE

To provide updated evidence-based guidelines for the management of osteoporosis in postmenopausal women in Belgium.

METHODS

The Belgian Bone Club (BBC) gathered a guideline developer group. Nine "Population, Intervention, Comparator, Outcome" (PICO) questions covering screening, diagnosis, non-pharmacological and pharmacological treatments, and monitoring were formulated. A systematic search of MEDLINE, the Cochrane Database of Systematic Reviews, and Scopus was performed to find network meta-analyses, meta-analyses, systematic reviews, guidelines, and recommendations from scientific societies published in the last 10 years. Manual searches were also performed. Summaries of evidence were provided, and recommendations were further validated by the BBC board members and other national scientific societies' experts.

RESULTS

Of the 3840 references in the search, 333 full texts were assessed for eligibility, and 129 met the inclusion criteria. Osteoporosis screening using clinical risk factors should be considered. Patients with a recent (<2 years) major osteoporotic fracture were considered at very high and imminent risk of future fracture. The combination of bone mineral density measured by dual-energy X-ray absorptiometry and 10-year fracture risk was used to categorize patients as low or high risk. Patient education, the combination of weight-bearing and resistance training, and optimal calcium intake and vitamin D status were recommended. Antiresorptive and anabolic osteoporosis treatment should be considered for patients at high and very high fracture risk, respectively. Follow-up should focus on compliance, and patient-tailored monitoring should be considered.

CONCLUSION

BBC guidelines and 25 guideline recommendations bridge the gap between research and clinical practice for the screening, diagnosis, and management of osteoporosis.

Long-Term Bisphosphonate Therapy in Osteogenesis Imperfecta

PURPOSE OF REVIEW

Osteogenesis imperfecta (OI) is a genetic bone disorder resulting in bone fragility. It has a heterogeneous phenotype which typically includes reduced bone mass, multiple fractures, deformity, and chronic disability. Bisphosphonate treatment remains the first-line medical management, but there is still debate on aspects of its effectiveness. This review summarizes current knowledge about long-term bisphosphonate use in OI with recommendations on clinical application.

RECENT FINDINGS

Bisphosphonates increase bone mineral density, most notably of the vertebrae, and reduce fracture risk in the pediatric OI population. Gains in strength and mobility, together with the permissive effect on orthopedic surgery (e.g., in combination with intramedullary rodding) and physiotherapy, have resulted in improved quality of life for those with OI. As experience in its use continues, the risks and benefits of long-term bisphosphonate treatment in OI are slowly emerging. Patient registries containing data on genotype, phenotype, fractures, bisphosphonate treatment, orthopedic intervention, and functional outcomes are essential for systematic evaluation given the lack of large multi-centered randomized control trials.

Drug holidays from bisphosphonates and denosumab in postmenopausal osteoporosis: EMAS position statement

BACKGROUND

Bisphosphonates and denosumab are used extensively in the treatment of postmenopausal osteoporosis. Despite their proven efficacy in the reduction of vertebral and non-vertebral fractures, their optimal duration of use has not been determined. The occurrence of adverse effects, such as osteonecrosis of the jaw (ONJ) and atypical femoral fractures (AFF), has raised the issue of bisphosphonate or denosumab discontinuation ("drug holiday") after a certain treatment period.

AIM

To assess the effect of bisphosphonate and denosumab discontinuation on fracture risk, as well as its possible benefits in reducing the risk of adverse effects.

METHODS

Systematic review and consensus of expert opinion.

RESULTS AND CONCLUSIONS

Discontinuation of bisphosphonates should be considered in all patients who have beentreated for more than five years with alendronate, risedronate or zoledronic acid. In view of the limited evidence, no robust recommendations can be made for ibandronate and denosumab. If the patient has not experienced fractures before or during therapy and the fracture risk is low, a "drug holiday" canbe recommended. Although there is no solid evidence, 1-2 years for risedronate, 3-5 years for alendronate and 3-6 years for zoledronic acid are suggested. After this time, the patient should be reassessed. If a new fracture is experienced, or fracture risk has increased or BMD remains low (femoral neck T-score ≤-2.5), anti-osteoporotic treatment should be resumed. In the case of denosumab discontinuation, close monitoring is suggested, due to the possibility of rebound fractures.

Drug-Related Adverse Events of Osteoporosis Therapy

Postmenopausal osteoporosis is associated with microarchitectural deterioration and increased risk of fracture. Osteoporosis therapy effectively reduces the risk of vertebral, nonvertebral, and hip fracture and has been associated with increased survival. Currently approved treatments for osteoporosis include bisphosphonates, denosumab, selective estrogen receptor modulators, and teriparatide. This article reviews the adverse events of therapy associated with these medical interventions. Hormone replacement therapy is not included, because it is no longer indicated for the treatment of osteoporosis in all countries. Calcitonin and strontium ranelate are also not included, because their indication for osteoporosis has recently been limited or withdrawn.

Adverse cardiovascular effects of nitrogen-containing bisphosphonates in patients with osteoporosis: A nationwide population-based retrospective study

BACKGROUND

Bisphosphonates (BPs) are a class of medications used for the treatment of osteoporosis. Nitrogen-containing BPs (N-BPs) are more potent than non-nitrogenous BPs in terms of their effects on osteoporosis. We examined the effects of N-BPs on osteoporosis in patients included in a large population-based cohort study.

METHODS

Based on the National Health Insurance Research Database of Taiwan, we identified 1258 patients with osteoporosis who had received N-BP treatment from 2005 through 2010.

RESULTS

During the retrospective observation period, N-BP users had significantly higher incidence rates of hypertension, acute ischemic stroke, atrial fibrillation (Af), and congestive heart failure (CHF), and lower rates of hyperlipidemia than patients who did not use N-BPs. Overall, N-BP users had a higher incidence of cardiovascular events at the end of the follow-up period. After adjustment for age, sex, and comorbidities, the risk of developing cardiovascular events was significantly high for patients using N-BPs. Patients who received N-BP therapy also had a higher risk of Af and CHF than those who did not during the five-year follow-up period.

CONCLUSION

We provide evidence that patients with osteoporosis using N-BP therapy have an increased risk of CHF and Af. This potential risk should be weighed against the reduction in the risk of osteoporotic fractures.

Relationship of Bisphosphonate Therapy and Atrial Fibrillation/Flutter: Outcomes of Sleep Disorders in Older Men (MrOS Sleep) Study

BACKGROUND

Prior studies suggested an association between bisphosphonates and atrial fibrillation/flutter (AF) in women. This relationship in men, including those with sleep-disordered breathing (SDB), remains unclear. This study evaluated the relationship between bisphosphonate use and prevalent (nocturnal) and incident (clinically relevant) AF in a population of community-dwelling older men.

METHODS

A total of 2,911 male participants (mean age, 76 years) of the prospective observational Osteoporotic Fractures in Men Study sleep cohort with overnight in-home polysomnography (PSG) constituted the analytic cohort. Nocturnal AF from ECGs during PSG and incident AF events were centrally adjudicated. The association of bisphosphonate use and AF was examined using multivariable-adjusted logistic regression for prevalent AF and Cox proportional hazards regression for incident AF.

RESULTS

A total of 123 (4.2%) men were current bisphosphonate users. Prevalent nocturnal AF was present in 138 participants (4.6%). After multivariable adjustment, there was a significant association between current bisphosphonate use and prevalent AF (OR, 2.33; 95% CI, 1.13-4.79). In the subset of men with moderate to severe SDB, this association was even more pronounced (OR, 3.22; 95% CI, 1.29-8.03). However, the multivariable-adjusted relationship between bisphosphonate use and incident AF did not reach statistical significance (adjusted hazard ratio, 1.53; 95% CI, 0.96-2.45).

CONCLUSIONS

These results support an association between bisphosphonate use and prevalent nocturnal AF in community-dwelling older men. The data further suggest that those with moderate to severe SDB may be a particularly vulnerable group susceptible to bisphosphonate-related AF. Similar associations were not seen for bisphosphonate use and clinically relevant incident AF.

Efficacy, effectiveness and side effects of medications used to prevent fractures

There is an increasing number of effective therapies for fracture prevention in adults at risk of osteoporosis. However, shortcomings in the evidence underpinning our management of osteoporosis still exist. Evidence of antifracture efficacy in the groups of patients who most commonly use calcium and vitamin D supplements is lacking, the safety of calcium supplements is in doubt, and the safety and efficacy of high doses of vitamin D give cause for concern. Alendronate, risedronate, zoledronate and denosumab have been shown to prevent spine, nonspine and hip fractures; in addition, teriparatide and strontium ranelate prevent both spine and nonspine fractures, and raloxifene and ibandronate prevent spine fractures. However, most trials provide little information regarding long-term efficacy or safety. A particular concern at present is the possibility that oral bisphosphonates might cause atypical femoral fractures. Observational data suggest that the incidence of this type of fracture increases steeply with duration of bisphosphonate use, resulting in concern that the benefit-risk balance may become negative in the long term, particularly in patients in whom the osteoporotic fracture risk is not high. Therefore, reappraisal of ongoing use of bisphosphonates after about 5 years is endorsed by expert consensus, and 'drug holidays' should be considered at this time. Further studies are needed to guide clinical practice in this area.

Bisphosphonates and risk of cardiovascular events: a meta-analysis

Background and Objectives

Some evidence suggests that bisphosphonates may reduce atherosclerosis, while concerns have been raised about atrial fibrillation. We conducted a meta-analysis to determine the effects of bisphosphonates on total adverse cardiovascular (CV) events, atrial fibrillation, myocardial infarction (MI), stroke, and CV death in adults with or at risk for low bone mass.

Methods

A systematic search of MEDLINE and EMBASE through July 2014 identified 58 randomized controlled trials with longer than 6 months in duration that reported CV events. Absolute risks and the Mantel-Haenszel fixed-effects odds ratios (ORs) and 95% confidence intervals (CIs) of total CV events, atrial fibrillation, MI, stroke, and CV death were estimated. Subgroup analyses by follow-up duration, population characteristics, bisphosphonate types, and route were performed.

Results

Absolute risks over 25–36 months in bisphosphonate-treated versus control patients were 6.5% versus 6.2% for total CV events; 1.4% versus 1.5% for atrial fibrillation; 1.0% versus 1.2% for MI; 1.6% versus 1.9% for stroke; and 1.5% versus 1.4% for CV death. Bisphosphonate treatment up to 36 months did not have any significant effects on total CV events (14 trials; ORs [95% CI]: 0.98 [0.84–1.14]; I² = 0.0%), atrial fibrillation (41 trials; 1.08 [0.92–1.25]; I² = 0.0%), MI (10 trials; 0.96 [0.69–1.34]; I² = 0.0%), stroke (10 trials; 0.99 [0.82–1.19]; I² = 5.8%), and CV death (14 trials; 0.88 [0.72–1.07]; I² = 0.0%) with little between-study heterogeneity. The risk of atrial fibrillation appears to be modestly elevated for zoledronic acid (6 trials; 1.24 [0.96–1.61]; I² = 0.0%), not for oral bisphosphonates (26 trials; 1.02 [0.83–1.24]; I² = 0.0%). The CV effects did not vary by subgroups or study quality.

Conclusions

Bisphosphonates do not have beneficial or harmful effects on atherosclerotic CV events, but zoledronic acid may modestly increase the risk of atrial fibrillation. Given the large reduction in fractures with bisphosphonates, changes in osteoporosis treatment decision due to CV risk are not justified.

Long-term risks of bisphosphonate therapy

The objective this study was to summarize long-term risks associated with bisphosphonate therapy. Search of relevant medical publications for data from clinical trials, trial extensions, observational studies and post-marketing reports. Trial extensions and modifications did not reveal significant long-term safety issues. Observational data suggest at least as many benefits as risks. Post-marketing reports of musculoskeletal pain, osteonecrosis of the jaw and atypical femur fractures have been widely circulated in the lay press. Most focus on long-terms risks has been on osteonecrosis of the jaw and atypical femur fractures which occur in patients who have not received bisphosphonate therapy but may be more frequent (though still uncommon) in patients who have been on treatment for 5 years or longer. Lower-risk patients may be able to stop treatment after 3-5 years for a “drug holiday,” which mitigates these long-term risks; for higher risk patients, therapy through 6-10 years appears to be advisable and offers more benefits than risks.

Fracture prediction after discontinuation of 4 to 5 years of alendronate therapy: the FLEX study

IMPORTANCE

Discontinuation of bisphosphonate therapy after 3 to 5 years is increasingly considered, but methods to monitor fracture risk after discontinuation have not been established.

OBJECTIVE

To test methods of predicting fracture risk among women who have discontinued alendronate therapy after 4 to 5 years.

DESIGN, SETTING, AND PARTICIPANTS

The prospective Fracture Intervention Trial Long-term Extension (FLEX) study randomized postmenopausal women aged 61 to 86 years previously treated with 4 to 5 years of alendronate therapy to 5 more years of alendronate or placebo from 1998 through 2003; the present analysis includes only the placebo group. Hip and spine dual-energy x-ray absorptiometry (DXA) were measured when placebo was begun (FLEX baseline) and after 1 to 3 years of follow-up. Two biochemical markers of bone turnover, urinary type 1 collagen cross-linked N-telopeptide (NTX) and serum bone-specific alkaline phosphatase (BAP), were measured at FLEX baseline and after 1 and 3 years.

MAIN OUTCOMES AND MEASURES

Symptomatic spine and nonspine fractures occurring after the follow-up measurement of DXA or bone turnover.

RESULTS

During 5 years of placebo, 94 of 437 women (22%) experienced 1 or more symptomatic fractures; 82 had fractures after 1 year. One-year changes in hip DXA, NTX, and BAP were not related to subsequent fracture risk, but older age and lower hip DXA at time of discontinuation were significantly related to increased fracture risk (lowest tertile of baseline femoral neck DXA vs other 2 tertiles relative hazard ratio, 2.17 [95% CI, 1.38-3.41]; total hip DXA relative hazard ratio, 1.87 [95% CI, 1.20-2.92]).

CONCLUSIONS AND RELEVANCE

Among postmenopausal women who discontinue alendronate therapy after 4 to 5 years, age and hip BMD at discontinuation predict clinical fractures during the subsequent 5 years. Follow-up measurements of DXA 1 year after discontinuation and of BAP or NTX 1 to 2 years after discontinuation are not associated with fracture risk and cannot be recommended.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00398931.

Acute effect of zoledronic acid infusion on atrial fibrillation development in patients with osteoporosis

Objective:

There is ongoing controversy related to the relationship between bisphosphonates and atrial fibrillation (AF). Our aim in this study was to evaluate the potential acute effect of zoledronic acid (ZA) infusion on AF development by using 24-hour Holter recordings.

Methods:

The study was designed to be a self-controlled case series study, and 33 consecutive patients with osteoporosis (29 females, age: 62.3±9.0 years) who were scheduled to receive ZA infusion constituted the study population. Patients underwent 24-hour Holter rhythm recordings at two different times; the first one was 48 hours before the planned ZA infusion, and the second one was on the morning of the infusion day. Heart rate, frequency and type of arrhythmias, as well as heart rate variability (HRV) from the two recordings were compared.

Results:

There were no episodes of AF greater than 30 sec in any of the 24-hour Holter recordings obtained before and on the day of drug infusion. Holter recordings before drug infusion showed that only 1 patient had an atrial run of 3 beats long. Holter recordings obtained on the day of drug infusion revealed that 5 patients (15.2%) had atrial runs with lengths ranging between 3 and 12 beats (p=0.046). Regarding HRV variables, SDANN values were found to be significantly depressed on the day of ZA infusion (113.6±26.9 vs. 98.2±29.9, p=0.007).

Conclusion:

None of the patients developed AF during or early after ZA infusion. However, there was an increase in atrial ectopy in some patients, which might be due to alterations in cardiac autonomic activity.

Bisphosphonates for treatment of osteoporosis: expected benefits, potential harms, and drug holidays

OBJECTIVE

To outline the efficacy and risks of bisphosphonate therapy for the management of osteoporosis and describe which patients might be eligible for bisphosphonate "drug holiday."

QUALITY OF EVIDENCE

MEDLINE (PubMed, through December 31, 2012) was used to identify relevant publications for inclusion. Most of the evidence cited is level II evidence (non-randomized, cohort, and other comparisons trials).

MAIN MESSAGE

The antifracture efficacy of approved first-line bisphosphonates has been proven in randomized controlled clinical trials. However, with more extensive and prolonged clinical use of bisphosphonates, associations have been reported between their administration and the occurrence of rare, but serious, adverse events. Osteonecrosis of the jaw and atypical subtrochanteric and diaphyseal femur fractures might be related to the use of bisphosphonates in osteoporosis, but they are exceedingly rare and they often occur with other comorbidities or concomitant medication use. Drug holidays should only be considered in low-risk patients and in select patients at moderate risk of fracture after 3 to 5 years of therapy.

CONCLUSION

When bisphosphonates are prescribed to patients at high risk of fracture, their antifracture benefits considerably outweigh their potential for harm. For patients taking bisphosphonates for 3 to 5 years, reassess the need for ongoing therapy.

Update on long-term treatment with bisphosphonates for postmenopausal osteoporosis: a systematic review

INTRODUCTION

Osteoporosis is a progressive skeletal disorder that requires long-term treatment. However, there is little guidance regarding optimal treatment duration and what the treatment discontinuation and retreatment criteria should be. Given that bisphosphonates are the most commonly prescribed class of agent for the treatment of osteoporosis, we reviewed the long-term data relating to these therapies and discussed the considerations for using bisphosphonates in postmenopausal women with osteoporosis.

METHODS

A PubMed search, using the search terms 'bisphosphonate', 'postmenopausal osteoporosis' and 'long term' and/or 'extension' was conducted in January 2013. Results from nine controlled studies that prospectively assessed alendronate, risedronate, ibandronate or zoledronic acid in women with postmenopausal osteoporosis were reviewed.

FINDINGS

Clinical studies in postmenopausal women with osteoporosis showed that long-term use of bisphosphonates resulted in persistent antifracture and bone mineral density (BMD) increasing effects beyond 3 years of treatment. No unexpected adverse events were identified in these studies and the long-term tolerability profiles of bisphosphonates remain favorable. Data from the withdrawal extension studies of alendronate and zoledronic acid also showed that residual fracture benefits were seen in patients who discontinued treatment for 3 to 5 years after an initial 3- to 5-year treatment period. BMD monitoring and fracture risk assessments should be conducted regularly to determine whether treatment could be stopped or should be reinitiated. Patients exhibiting T-scores<-2.5 or who have suffered a new fracture while on treatment should continue treatment, while patients with T-scores>-2.5 could be considered for discontinuation of active treatment while undergoing continued monitoring of their bone health. The duration and potential discontinuation of treatment should be personalized for individual patients based on their response to treatment, fracture risk and comorbidities.

Safety issues with bisphosphonate therapy for osteoporosis

Randomized controlled trials have demonstrated the efficacy of bisphosphonates (BP) in improving BMD and reducing fracture risk. Various safety issues that were not noted in clinical trials have, however, now emerged with post-marketing surveillance and increasing clinical experience. The risk of atypical femoral fracture could increase with long-term use of BP, although absolute risk is very small, particularly when balanced against benefits. A drug holiday should be considered after 5 years of treatment for patients at low risk of fracture, although there is no official recommendation regarding this to guide clinicians. Osteonecrosis of the jaw from low-dose BP used for osteoporosis is very rare, and mainly a complication with high-dose i.v. BP used in oncology. The risk of atrial fibrillation too is negligible, and a definite link cannot be established between BP and oesophageal cancer. BP should be avoided in patients with severe renal impairment and during pregnancy and lactation because of limited safety data. Further epidemiological and clinical data are required to establish safety of BP in long-term users (>5 years) and provide evidence-based management.

Bisphosphonate drug holiday: choosing appropriate candidates

Osteoporosis related fractures contribute to morbidity and mortality in U.S. patients, placing a heavy financial burden on society. Randomized clinical trials involving over 30,000 subjects have established bisphosphonates' efficacy in reducing the incidence of fragility fractures. However, as bisphosphonates are retained for years in the skeleton, reports of adverse events from prolonged use are surfacing in the literature, namely, esophageal cancer, atrial fibrillation, osteonecrosis of the jaw, and atypical fracture development. The concept of a drug holiday has been proposed to potentially reduce incidence of these adverse events. This review will highlight the benefits and risks of bisphosphonate therapy and discuss the extension data available from the bisphosphonate trials. As randomized clinical trial evidence is not yet available on who may qualify for drug holiday, this review will provide suggestions for clinicians on identification of possible candidates and monitoring during a bisphosphonate drug holiday.

Drug-induced atrial fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with severe consequences, including symptoms, haemodynamic instability, increased cardiovascular mortality and stroke. While other arrhythmias such as torsades de pointes and sinus bradycardia are more typically thought of as drug induced, AF may also be precipitated by drug therapy, although ascribing causality to drug-associated AF is more difficult than with other drug-induced arrhythmias. Drug-induced AF is more likely to occur in patients with risk factors and co-morbidities that commonly co-exist with AF, such as advanced age, alcohol consumption, family history of AF, hypertension, thyroid dysfunction, sleep apnoea and heart disease. New-onset AF has been associated with cardiovascular drugs such as adenosine, dobutamine and milrinone. In addition, medications such as corticosteroids, ondansetron and antineoplastic agents such as paclitaxel, mitoxantrone and doxorubicin have been reported to induce AF. Whether bisphosphonate drugs are associated with new-onset AF remains controversial and requires further study. The potential contribution of specific drug therapy should be considered when patients present with new-onset AF.

Bisphosphonates and glucocorticoid-induced osteoporosis: efficacy and tolerability

In this review, the efficacy concern relating to bisphosphonates therapy for glucocorticoid-induced osteoporosis is considered. Sole the randomised clinical trials that including more than 50 patients in each treatment arm were considered. This review also covered the safety of bisphosphonates in the setting of glucocorticoid-induced osteoporosis with specific focus on atrial fibrillation, osteonecrosis of the jaw, upper gastrointestinal adverse events and esophageal cancer risk, atypical fractures and renal safety. These last adverse events have been selected due to the rationale of a possible additive, pathophysiologic or synergetic, deleterious effect of bisphosphonates and glucocorticoid on these organs. The available evidence for glucocorticoid-induced osteoporosis treatment and management is much less important than for post-menopausal osteoporosis. However, based on randomised clinical trials with lumbar spine BMD as the primary endpoint after one year, bisphosphonates can be considered as efficacious. Alendronate, etidronate, risedronate and zoledronate prevented declines in spine BMD in adults receiving glucocorticoid. Treatment and prevention studies in glucocorticoid-induced osteoporosis have a short duration and have included smaller population than in post-menopausal osteoporosis. However in this setting, the safety profile of bisphosphonates in glucocorticoid-induced osteoporosis was good. Long-term use of bisphosphonates in patients treated with glucocorticoid might be cautiously monitored in order to prevent adverse effects.

Bisphosphonates in the treatment of osteoporosis

Bisphosphonates are widely used in the treatment of osteoporosis to reduce fracture risk. Because of their long retention time in bone and uncommon side effects, questions have been raised about the optimal duration of therapy. Potential side effects appear to be rare and may not be causally related. Although there is no strong science to guide "drug holidays," there appears to be some lingering antifracture benefit when treatment is stopped, so some time off treatment should be offered to most patients on long-term bisphosphonate therapy. For most patients with osteoporosis, the benefits of treatment outweigh the risks.

New understanding and treatments for osteoporosis

To summarize promising areas of investigation in osteoporosis and to stimulate further research in this area, as discussed in a recent international conference. Over the recent years, there has been an improvement in the knowledge of molecular pathways involved in bone formation and resorption with the development of new drugs to treat osteoporosis. Intact parathyroid hormone, teriparatide, and anti-sclerostin monoclonal antibody are anabolic drugs, whereas denosumab and odanacatib are anti-resorptive drugs with more reversible effects as compared to bisphosphonates. Anabolic and anti-resorptive agents have different effects on bone, and research in this area includes the efficacy of combination and sequential therapies with them. New insights in the molecular pathways of bone remodeling have clarified the mechanisms responsible for skeletal fragility in several forms of secondary osteoporosis, such as that occurring in type 2 diabetes, following drug exposure and systemic inflammatory diseases. Future research is needed to address the efficacy of anti-osteoporotic drugs in these more recently recognized conditions of skeletal fragility. Osteoporosis continues to be an important field of biomedical research.