Time trends in oral bisphosphonate initiation in Ontario, Canada over 20 years reflect drug policy and healthcare delivery changes

Methodological guidance for the use of real-world data to measure exposure and utilization patterns of osteoporosis medications

Observational studies of osteoporosis medications can provide critical real-world evidence (RWE) that fills knowledge gaps left by clinical trials. However, careful consideration of study design is needed to yield reliable estimates of association. In particular, obtaining valid measurements of exposure to osteoporosis medications from real-world data (RWD) sources is complicated due to different medication classes, formulations, and routes of administration, each with different pharmacology. Extended half-lives of bisphosphonates and extended dosing of denosumab and zoledronic acid require particular attention. In addition, prescribing patterns and medication taking behavior often result in gaps in therapy, switching, and concomitant use of osteoporosis therapies. In this review, we present important considerations and provide specialized guidance for measuring osteoporosis drug exposures in RWD. First, we compare different sources of RWD used for osteoporosis drug studies and provide guidance on identifying osteoporosis medication use in these data sources. Next, we provide an overview of osteoporosis pharmacology and how it can influence decisions on exposure measurement within RWD. Finally, we present considerations for the measurement of osteoporosis medication exposure, adherence, switching, long-term exposures, and drug holidays using RWD. Ultimately, a thorough understanding of the differences in RWD sources and the pharmacology of osteoporosis medications is essential to obtain valid estimates of the relationship between osteoporosis medications and outcomes, such as fractures, but also to improve the critical appraisal of published studies.

Epidemiology of Osteoporosis

Background

India has a population capacity of 1.2 billion people. With a worldwide aging population, the prevention and management of osteoporosis has become a significant healthcare challenge. It is crucial to recognize the factors impacting poor bone health and appreciate the many hurdles to treat the disease to provide a better quality of life and decrease the financial burden on healthcare.

Purpose

In this review article, we discuss the epidemiology of osteoporosis and address the definition, incidence, and prevalence, geographical variation in the occurrence of osteoporosis, and the risk factors for osteoporosis.

Methods

Search terms using various combinations of the keywords 'osteoporosis,' 'epidemiology,' 'incidence,' 'prevalence,' 'fracture,' 'India,' 'world,' 'screening,' and 'FRAX' was done to review all relevant literature till June 2023.

Results & Conclusion

India has a recent estimate of population capacity of 1.2 billion people. Various studies have revealed an osteoporosis prevalence in Indian women ranging from 8% to 62%. Poor dietary calcium intake, low vitamin D, and lifestyle changes contribute to osteoporosis.

Cost-effectiveness of romosozumab for the treatment of postmenopausal women at very high risk of fracture in Canada

This study evaluated the cost-effectiveness of 1 year of romosozumab followed by alendronate versus oral bisphosphonates alone in women with postmenopausal osteoporosis at very high risk for fracture in Canada. Results showed that romosozumab sequenced to alendronate is a cost-effective treatment option, dominating both alendronate and risedronate alone.

PURPOSE

To demonstrate the value of romosozumab sequenced to alendronate compared to alendronate or risedronate alone, for the treatment of osteoporosis in postmenopausal women with a history of osteoporotic fracture and who are at very high risk for future fracture in Canada.

METHODS

A Markov model followed a hypothetical cohort of postmenopausal osteoporotic women at very high risk for future fractures, to estimate the cost-effectiveness of romosozumab and alendronate compared to oral bisphosphonates alone. A total treatment period of 5 years was assumed. Quality-adjusted life years and costs were estimated for each comparator across health states defined by different types of fragility fractures.

RESULTS

Romosozumab/alendronate was associated with a lifetime gain of 0.103 and 0.127 QALYs and a cost reduction of $343 and $3805, relative to alendronate and risedronate, respectively. These results were driven by a reduction of the number of fractures (2561 per 1000 patients, versus 2700 for alendronate and 2724 for risedronate over lifetime). Romosozumab/alendronate had the highest probability of being cost-effective, relative to alendronate and risedronate, at any willingness to pay threshold value.

CONCLUSION

Romosozumab/alendronate was associated with reduced costs and greater benefit relative to other comparators. Probabilistic, deterministic, and scenario analyses indicate that romosozumab/alendronate represents the best value for money; the uncertainty analyses are robust, and therefore romosozumab should be considered for reimbursement by public drug plans in Canada .

Comparative Fracture Risk During Osteoporosis Drug Holidays After Long-Term Risedronate Versus Alendronate Therapy : A Propensity Score-Matched Cohort Study

BACKGROUND

An osteoporosis drug holiday is recommended for most patients after 3 to 5 years of therapy. Risedronate has a shorter half-life than alendronate, and thus the residual length of fracture protection may be shorter.

OBJECTIVE

To examine the comparative risks of drug holidays after long-term (≥3 years) risedronate versus alendronate therapy.

DESIGN

Population-based, matched, cohort study.

SETTING

Province-wide health care administrative databases providing comprehensive coverage to Ontario residents aged 65 years or older between November 2000 and March 2020.

PATIENTS

Persons aged 66 years or older who had long-term risedronate therapy and a drug holiday were matched 1:1 on propensity score to those who had long-term alendronate therapy and a drug holiday.

MEASUREMENTS

The primary outcome was hip fracture within 3 years after a 120-day ascertainment period. Secondary analyses included shorter follow-up and sex-specific estimates. Cox proportional hazards models were used to estimate hazard ratios (HRs) for fracture risk between groups.

RESULTS

A total of 25 077 propensity score-matched pairs were eligible (mean age, 81 years; 81% women). Hip fracture rates were higher among risedronate than alendronate drug holidays (12.4 and 10.6 events, respectively, per 1000 patient-years; HR, 1.18 [95% CI, 1.04 to 1.34]; 915 total hip fractures). The association was attenuated when any fracture was included as the outcome (HR, 1.07 [CI, 1.00 to 1.16]) and with shorter drug holidays (1 year: HR, 1.03 [CI, 0.85 to 1.24]; 2 years: HR, 1.14 [CI, 0.96 to 1.32]).

LIMITATION

Analyses were limited to health care administrative data (potential unmeasured confounding), and some secondary analyses contained few events.

CONCLUSION

Drug holidays after long-term therapy with risedronate were associated with a small increase in risk for hip fracture compared with alendronate drug holidays. Future research should examine how best to mitigate this risk.

PRIMARY FUNDING SOURCE

Canadian Institutes of Health Research.

Changes in the pharmacological management of rheumatoid arthritis over two decades

Objectives

To assess whether modern management of RA has reduced the prescription of oral corticosteroids and NSAIDs and to evaluate use of pharmacological prophylaxis strategies.

Methods

Using the Clinical Practice Research Datalink, we explored long-term (≥3/12 months; ≥6/12 in sub-analyses) DMARD, corticosteroid and NSAID prescribing (annually, in the year post-diagnosis and across the patient’s life course to 15 years post-diagnosis), annual proportion with co-prescribing for prophylaxis of associated bone (corticosteroids, women only) and gastrointestinal (NSAIDs) comorbidity.

Results

Reported incidence of RA was 5.98 (0.37) per 10 000 person-years and prevalence was 0.91% (0.014) in 2017. In 71 411 RA patients, long-term DMARD prescribing initially rose post-diagnosis from 41.6% in 1998 to 67.9% in 2009. Corticosteroid prescribing changed little, overall [22.2% in 1998, 19.1% in 2016; incident risk ratio (IRR) 0.92, 95% CI: 0.82, 1.03] and across the life course from the first to fifteenth year (22.2% to 16.9%). NSAID prescribing declined from 57.7% in 1998, and significantly so from 2008, to 27.1% in 2016 (IRR 0.50, 95% CI: 0.44, 0.56). This continued across the life course (41.2% to 28.4%). Bone prophylaxis increased to 68.1% in 2008 before declining to 56.4% in 2017; gastrointestinal prophylaxis increased from 11.5% in 1998 to 62.6% in 2017. Sub-analyses showed consistent patterns.

Conclusion

Despite modern treatment strategies, corticosteroid prescribing in RA patients remains substantial and persists beyond 6 months once initiated. Rheumatologists need to determine causes and develop strategies to reduce corticosteroid use to minimize adverse event occurrence.

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

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Duration of Bisphosphonate Drug Holidays in Osteoporosis Patients: A Narrative Review of the Evidence and Considerations for Decision-Making

Bisphosphonates are first-line therapy for osteoporosis, with alendronate, risedronate, and zoledronate as the main treatments used globally. After one year of therapy, bisphosphonates are retained in bone for extended periods with extended anti-fracture effects after discontinuation. Due to this continued fracture protection and the potential for rare adverse events associated with long-term use (atypical femoral fractures and osteonecrosis of the jaw), a drug holiday of two to three years is recommended for most patients after long-term bisphosphonate therapy. The recommendation for a drug holiday up to three years is derived primarily from extensions of pivotal trials with alendronate and zoledronate and select surrogate marker studies. However, certain factors may modify the duration of bisphosphonate effects on a drug holiday and warrant consideration when determining an appropriate time off-therapy. In this narrative review, we recall what is currently known about drug holidays and discuss what we believe to be the primary considerations and areas for future research regarding drug holiday duration: total bisphosphonate exposure, type of bisphosphonate used, bone mineral density and falls risk, and patient sex and body weight.

Are Nursing Home Residents With Dementia Appropriately Treated for Fracture Prevention?

Clinicians struggle with whether to prescribe osteoporosis medications for fracture prevention for older nursing home (NH) residents with dementia, given the lack of evidence in this population. To better understand real-world clinical practice, we conducted a retrospective cohort study examining patterns of fracture prevention medication use for older NH residents with dementia and high fracture risk. Data sources included 2015-16 Medicare claims, Part D prescriptions, and Minimum Data Set (MDS) assessments. Among NH residents aged 65+ with dementia and prior fracture or high fracture risk based on the MDS FRAiL (Fracture Risk Assessment in Long-term care), we assessed medications for fracture prevention using prescription data from 1 year prior through 90 days after the first MDS assessment. Multivariable logistic regression was used to evaluate factors associated with receiving treatment. Most of the sample (n = 72,639) was >80 years (78%), female (82%), and white (88%); 63% had moderate/severe dementia and 60% had an osteoporosis diagnosis. Only 11.6% received fracture prevention medications. In adjusted analyses, treated residents were more likely to be female, Hispanic or other non-black minority, <90 years old, and newly admitted to the NH. Other associated factors included osteoporosis diagnosis, walker or wheelchair use, bone disorders (eg, Paget disease), >5 medications, steroid or proton pump inhibitor use, and regions outside of the Northeast. Resident characteristics suggestive of comorbidity burden and worsening dementia were associated with reduced likelihood of treatment. Low use of fracture prevention medications for NH residents with dementia may reflect an attempt by prescribers reconcile medication use with changing goals of care, or inappropriate underuse in patients who still have high fracture risk. Additional research is needed to help clinicians better evaluate when to use these medications in this heterogeneous and vulnerable population.

Etidronate down-regulates Toll-like receptor 2 ligand-induced chemokine production by inhibiting MyD88 expression and NF-κB activation

OBJECTIVE

Pretreatment of J774.1 cells with etidronate, a non-nitrogen-containing bisphosphonate (non-NBP) used as an antibone resorptive drug, was previously reported to inhibit Toll-like receptor (TLR) 2 agonist-induced proinflammatory cytokine production. The present study aimed to examine the effects of etidronate on chemokine production by human monocytic U937 cells incubated with Pam₃Cys-Ser-(Lys)₄ (Pam₃CSK₄, a TLR2 ligand) and lipid A (a TLR4 ligand).

METHODS

U937 cells were pretreated with or without etidronate, and then incubated with or without Pam₃CSK₄ or lipid A. Levels of secreted human interleukin (IL)-8 and monocyte chemoattractant protein-1 (MCP-1) in culture supernatants and activation of nuclear factor-κB (NF-κB) p65 were measured by enzyme-linked immunosorbent assay (ELISA). Cytotoxicity was determined by measuring lactate dehydrogenase (LDH) activity in supernatants. Expression of intracellular adhesion molecule (ICAM)-1 and MyD88 was analyzed by flow cytometry and Western blot analysis, respectively.

RESULTS

Etidronate down-regulated IL-8 and MCP-1 production and NF-κB p65 activation induced by Pam₃CSK_4, but not lipid A, in U937 cells. Etidronate also inhibited MyD88 expression in U937 cells incubated with Pam₃CSK₄.

CONCLUSION

Etidronate down-regulates IL-8 and MCP-1 production in U937 cells by inhibiting both the expression of MyD88 and activation of NF-κB p65 in the TLR2, but not TLR4, pathway.

Bisphosphonate and denosumab initiation in older adults in Ontario, Canada: a population-based cohort study

We provide an update on how commonly prescribed osteoporosis therapies are being initiated in older adults in Ontario. Patients newly prescribed denosumab are older, more often female, and have more comorbidities than those prescribed bisphosphonates. Their characteristics, monitoring, and persistence with prescribed therapy differ from clinical trial participants. Real-world studies on oral bisphosphonates and denosumab might be valuable.

PURPOSE

To provide a contemporary view on oral bisphosphonate and denosumab prescribing to older adults in routine care.

METHODS

Using linked healthcare databases, we conducted a population-based cohort study of adults ≥ 66 years newly prescribed oral bisphosphonates or denosumab between February 2013 and March 2017 in Ontario, Canada. We captured their clinical characteristics, monitoring, and continuous use of prescribed therapies. We illustrate how "real-world" new users of bisphosphonates and denosumab differ from randomized controlled trial (RCT) participants.

RESULTS

There were 107,847 individuals newly prescribed oral bisphosphonates (n = 59,996) or denosumab (n = 47,851) over the study period. Compared with new users of oral bisphosphonates, denosumab users were older (mean age 79.1 vs. 75.7 years), more often female (97.2 vs. 71.8%), from non-rural areas (93.9 vs. 89.9%), and resided in long-term care (10.9 vs. 3.3%). They had more comorbidities including dementia, falls, and fractures. Following their new prescription, denosumab users had more frequent testing of serum calcium. Duration of continuous use of denosumab was longer than bisphosphonates, and more bisphosphonate users had evidence of treatment discontinuation (56.7 bisphosphonate vs. 33.8% denosumab users discontinued therapy at 365 days). Compared with RCT participants, a higher proportion of "real-world" bisphosphonate and denosumab users had comorbidities including advanced kidney disease.

CONCLUSION

The clinical characteristics and monitoring of new users of bisphosphonates and denosumab generally align with practice guidelines, product monographs, and drug reimbursement criteria. Given differences between real-world users and RCT participants, there may be a role for safety and effectiveness studies of bisphosphonates and denosumab in routine care.