Alendronate use and bone mineral density gains in women with moderate-severe (stages 3B-5) chronic kidney disease: an open cohort multivariable and propensity score analysis from Funen, Denmark

Cardiovascular Safety and Fracture Prevention Effectiveness of Denosumab Versus Oral Bisphosphonates in Patients Receiving Dialysis : A Target Trial Emulation

BACKGROUND

Dialysis patients have high rates of fracture morbidity, but evidence on optimal management strategies for osteoporosis is scarce.

OBJECTIVE

To determine the risk for cardiovascular events and fracture prevention effects with denosumab compared with oral bisphosphonates in dialysis-dependent patients.

DESIGN

An observational study that attempts to emulate a target trial.

SETTING

A Japanese administrative claims database (April 2014 to October 2022).

PATIENTS

Adults aged 50 years or older who have initiated denosumab or oral bisphosphonates for osteoporosis in dialysis-dependent patients.

MEASUREMENTS

The safety outcome was major adverse cardiac events (MACE). The effectiveness outcome was a composite of all fractures. Follow-up was 3 years.

RESULTS

A total of 1032 patients were identified (658 denosumab users and 374 oral bisphosphonate users). Overall average age was 74.5 years, and 62.9% were women. The weighted 3-year risk difference for MACE was 8.2% (95% CI, -0.2% to 16.7%), with a weighted 3-year risk ratio of 1.36 (CI, 0.99 to 1.87). The weighted 3-year risk difference for composite fractures was -5.3% (CI, -11.3% to -0.6%), and the weighted 3-year risk ratio was 0.55 (CI, 0.28 to 0.93).

LIMITATIONS

Lack of clinical data on kidney or osteoporosis disease severity and cardiovascular or other metabolic risk with residual confounding. Safety outcomes did not include kidney end points.

CONCLUSION

It was estimated that, compared with oral bisphosphonates, denosumab lowered the risk for fractures by 45% and increased the risk for MACE by 36%. The estimates, however, are imprecise and need to be confirmed in future studies.

PRIMARY FUNDING SOURCE

None.

Clinical Utility of Bone Turnover Markers in Chronic Kidney Disease

Chronic kidney disease (CKD) often leads to mineral and bone disorders (CKD-MBDs), which are nearly universal in patients undergoing dialysis. CKD-MBD includes abnormal calcium-phosphate metabolism, vascular and soft tissue calcification, and bone abnormalities (renal osteodystrophy [ROD]). Bone fragility in CKD occurs due to low bone mass and poor bone quality, and patients with CKD have higher fracture and mortality rates. Bone histomorphometry is the gold standard for ROD diagnosis; however, it is labor-intensive and expensive. The Kidney Disease Improving Global Outcomes clinical practice guidelines on CKD-MBD suggest serum parathyroid hormone (PTH) and bone-specific alkaline phosphatase (bone ALP) for predicting bone turnover in ROD. In this review, we focus on the role of PTH and bone turnover markers, intact procollagen type N-terminal propeptide of type I collagen, bone ALP, and tartrate-resistant acid phosphatase 5b in diagnosing ROD, predicting fractures, and guiding treatment in patients with CKD.

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.