Long-Term Effect of Denosumab on Bone Disease in Patients with CKD

The Challenge of Fractures in Patients With Chronic Kidney Disease

OBJECTIVE

People with chronic kidney disease (CKD) are at increased risk of fractures in comparison to the non-CKD population, and fractures are associated with high mortality and worsening quality of life. However, the approach for evaluation of bone disease and fracture risk in CKD is different from the approach in the general population.

METHODS

The authors conducted a literature review of PubMed to include studies on pathophysiology of CKD mineral bone disorder, fracture risk assessment, and therapeutic options in the setting of CKD.

RESULTS

The higher risk observed in the CKD population is related to the complex interplay of changes in bone turnover (T), mineralization (M), and volume (V), along with other risk factors accumulated as glomerular filtration rate declines. The diagnosis of the type of renal osteodystrophy is not based only on assessment of bone density and traditional risk factors for osteoporosis. There are limitations of currently available fracture risk tools in the CKD population. Treatment choice should take into consideration the 3 components of the TMV classification along with the stage of kidney disease and comorbidities, but the assessment of these components has not been well established.

CONCLUSIONS

Current data are limited on efficacy and safety of treatments for fracture prevention in CKD. As new medications for the treatment of osteoporosis become available, there is an urgency to establish more clear guidelines for the diagnosis, fracture risk stratification, and treatment of bone disease in CKD.

Long-Term Changes in Parameters of Bone Quality in Kidney Transplant Recipients Treated with Denosumab

Kidney transplant recipients (KTRs) have an elevated fracture risk. While dual-energy X-ray absorptiometry (DXA) is commonly used to assess areal bone mineral density (aBMD), it does not capture all aspects of bone quality. We investigated the long-term effects on bone DXA-derived indices of bone quality in KTRs treated with denosumab and untreated with denosumab. This is a retrospective study, including KTRs treated with denosumab and untreated age and sex-matched KTR controls. DXA-derived parameters, including trabecular bone score (TBS) and 3D-DXA parameters, were measured at the lumbar spine and femur at baseline and after four years. Hierarchical linear models were used to assess the between-group effect of treatment over time, also adjusting for site-specific aBMDs. We enrolled 23 KTRs treated with denosumab and 23 KTR denosumab-untreated KTRs. Significant between-group differences over time in favor of the denosumab group were observed for TBS (0.843, 95%CI 0.439; 1.248,p < 0.001), trabecular volumetric BMD at the total hip (Tb.vBMD TH) (13.492, 95%CI 1.707; 25.278, p = 0.003), cortical volumetric BMD at the femoral neck (Ct.vBMD FN) (28.766, 95%CI 8.373; 49.158, p = 0.008), cortical surface BMD at the total hip (c.sBMD TH) (10.507, 95%CI 4.140; 16.873,p = 0.002), cortical surface at the femoral neck (c.sBMD FN) (8.795, 95%CI 2.818; 14.771, p = 0.006), and cortical thickness at the total hip (Ct.th.TH) (0.075, 95%CI 0.020; 0.130, p = 0.010). After adjusting for BMD, the differences on TBS and Ct.vBMD FN and c.sBMD FN remained significant. Denosumab treatment in KTRs was associated with better outcomes in terms of bone quality and geometry parameters, independent of changes in aBMD.

Use of 3D-DXA in the assessment of bone structure among patients with chronic kidney disease

Introduction

Patients in later stages of chronic kidney disease (CKD) have a 2- to 14-fold increase in fracture risk. Bone mineral density (BMD) assessment is limited due to the inability to measure trabecular and cortical bone characteristics and the interference of aortic calcifications.

Study objective

This study aimed to assess the trabecular bone score (TBS) and three-dimensional dual-energy X-ray absorptiometry (3D-DXA) in participants across all CKD stages.

Patients and methods

In total, 64 CKD patients (consisting of 28 female participants and 36 male participants, with an average age of 69.5 years) were included. There were 9, 12, 8, 9, 11, and 15 participants in stages G1, G2, G3a, G3b, G4, and G5 of CKD, respectively. BMD at the lumbar spine (LS) and proximal femur, as well as the LS TBS, were analyzed. The proximal femur parameters such as cortical and trabecular volumetric (v)BMD, cortical thickness (CTh), and surface (s)BMD at the total hip (TH) and femoral neck (FN) were analyzed using 3D-Shaper software.

Results

Comparison between the earlier stages (G1-G3a) and the later CKD stages (G3b-G5) showed significant differences in carboxy terminal collagen crosslinks (CTx) (386 vs.1053 ng/L), TH areal bone mineral density (aBMD; 0.991 vs. 0.859 g/cm2), cortical TH vBMD (831 vs. 795 mg/cm3), FN (837 vs. 788 mg/cm3), TH cortical sBMD (170 mg/cm2), and TH Cth (2.03 vs. 1.92 mm; all p < 0.05). Cross-sectional comparisons between each CKD stage showed a gradual decrease in the LS BMD, TH cortical vBMD, sBMD (FN and TH), and TH Cth. Strong positive associations between the glomerular filtration rate (GFR) and cortical parameters (FN/TH vBMD and TH Cth) were observed (p < 0.01).

Conclusion

In conclusion, advanced stages of CKD (G3b-G5) were associated with lower cortical bone parameters. The majority of the cortical parameters were correlated with the GFR, demonstrating a direct relationship between the kidney function and bone structure.

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.

Is denosumab an efficient and safe drug for osteoporosis in dialysis patients? Considerations and state of the art about its use in this setting

PURPOSE

In patients with chronic kidney disease (CKD), renal osteodystrophy may be associated with a progressive bone mass loss that increases fracture risk. Denosumab, a monoclonal antibody inhibiting osteoclast activity, is an antiresorptive medication used for the treatment osteoporosis.

METHODS

Its efficacy and safety were initially established in the FREEDOM study, showing a significant reduction in incident fractures in osteoporotic women treated with denosumab. Subsequent post hoc analyses showed its efficacy in patients stratified by kidney function, but these analyses did not include patients with advanced stages of CKD. The capability of denosumab in improving bone mineral density in uremic patients was evaluated in 12 studies including 461 dialysis patients with low bone mineral density. The improvement of bone mineral density was the final end point in these studies assessed during a follow-up of 6-60 months. Nine of these studies did not have hyperparathyroidism among criteria for patient inclusion and their participants may have low-turnover bone disease. Despite current recommendations, no patients underwent bone biopsy before denosumab therapy.

RESULTS

Overall, findings in these studies suggest that denosumab is a viable option for promoting bone mass recovery in patients with advanced stages of CKD having either high or low serum levels of PTH. However, the increase of bone mineral density was lower in patients with low serum markers of bone turnover at baseline. These studies also highlighted the need for calcium and vitamin D supplementation to prevent hypocalcemia that remains a serious concern.

CONCLUSIONS

Denosumab emerges as a potentially safe and effective option for enhancing bone health in CKD patients.

Effect of denosumab on the incidence of fractures and mortality in patients undergoing hemodialysis: A retrospective cohort study

BACKGROUND

Patients undergoing hemodialysis are at an elevated risk of fractures; however, substantial evidence for osteoporosis treatment in this population is lacking. We explored the efficacy of denosumab, an anti-IgG2 antibody that targets the receptor activator of nuclear factor-kappa B ligand, in reducing fracture incidence and all-cause mortality in patients undergoing hemodialysis.

METHODS

This retrospective cohort study-conducted from December 2013 to December 2022-evaluated the effects of denosumab on fracture incidence and all-cause mortality. Patients who initiated denosumab treatment during the study period were defined as the denosumab group, while those without a history of denosumab administration were defined as the non-denosumab group. Kaplan-Meier curves and log-rank tests were used to assess survival and fracture/mortality risks, respectively. Cox proportional hazards models were used to analyze both fractures and all-cause mortality.

RESULTS

Among 214 patients undergoing hemodialysis, 52 (24.3%) received denosumab. The median age was 73.0 ± 11.5 years, with 92 (43.0%) females, and the median dialysis duration was 59 months (interquartile range, 6-126). During the study, thirty-seven non-denosumab-treated patients had fractures compared to eight in the denosumab group. No significant differences were observed in the unadjusted model (HR, 0.53; 95% confidence interval (CI), 0.24-1.14). Adjusting for competing mortality and clinical factors, the HR remained at 0.64 (95% CI, 0.27-1.51). Regarding all-cause mortality, we found a statistically significant difference in the unadjusted model (HR, 0.61 [95% CI, 0.38-0.98]). A significant reduction in mortality was observed in the adjusted model (HR, 0.46 [95% CI, 0.26-0.80]). Notably, the denosumab group showed a significant decrease in mortality, particularly in cardiovascular disease-related cases (HR, 0.33 [95% CI, 0.14-0.78]).

CONCLUSIONS

Denosumab may reduce all-cause mortality in patients undergoing hemodialysis, particularly in those with cardiovascular complications. This finding offers a promising direction for osteoporosis treatment in patients undergoing hemodialysis.

Association between CKD-MBD and hip-bone microstructures in dialysis patients

Background

The longitudinal changes in hip-bone microstructures and estimated bone strength in dialysis patients, and the impact of chronic kidney disease-mineral and bone disorder (CKD-MBD) biomarkers on these changes, remain insufficiently explored.

Methods

This retrospective study examined changes in cortical and trabecular bone compartments and estimated bone-strength indices, obtained by using 3D-SHAPER software, in the hip regions of 276 dialysis patients over up to 2.5 years. We used multivariate mixed models to investigate the associations between time-dependent CKD-MBD biomarkers and bone health metrics.

Results

There was a significant decrease in areal bone mineral density (aBMD), integral volumetric BMD (vBMD), trabecular vBMD, cortical thickness and cortical surface BMD (sBMD). Similar deteriorations were found in estimated bone-strength indices [cross-sectional area (CSA), cross-sectional moment of inertia (CSMI), section modulus (SM) and buckling ratio]. Neither serum calcium nor phosphate levels were significantly associated with changes in three-dimensional parameters or estimated bone-strength indices. In contrast, serum alkaline phosphatase levels showed a significant inverse correlation with aBMD and CSA. The intact-parathyroid hormone (i-PTH) was significantly inversely correlated with aBMD, integral vBMD, trabecular vBMD, cortical thickness, cortical vBMD, CSA, CSMI and SM. When applying the KDIGO criteria as a sensitivity analysis, the higher PTH group had significant negative associations with aBMD, integral vBMD, cortical vBMD, cortical thickness and cortical sBMD. Notably, the lower PTH group showed a positive significant correlation with integral vBMD and trabecular vBMD.

Conclusions

Elevated PTH, not low PTH, was associated with deterioration of hip-bone microstructures. Better management of PTH levels may play a crucial role in the hip-bone microstructure in dialysis patients.

Management of chronic kidney disease: The current novel and forgotten therapies

Chronic kidney disease (CKD) is a progressive and incurable condition that imposes a significant burden on an aging society. Although the exact prevalence of this disease is unknown, it is estimated to affect at least 800 million people worldwide. Patients with diabetes or hypertension are at a higher risk of developing chronic kidney damage. As the kidneys play a crucial role in vital physiological processes, damage to these organs can disrupt the balance of water and electrolytes, regulation of blood pressure, elimination of toxins, and metabolism of vitamin D. Early diagnosis is paramount to prevent potential complications. Treatment options such as dietary modifications and medications can help slow disease progression. In our narrative review, we have summarized the available therapeutic options to slow the progression of chronic kidney disease. Many new drug treatments have recently become available, offering a beacon of hope and optimism in CKD management. Nonetheless, disease prevention remains the most critical step in disease management. Given the significant impact of CKD on public health, there is a pressing need for further research. With the development of new technologies and advancements in medical knowledge, we hope to find more effective diagnostic tools and treatments for CKD patients.

Effect of Denosumab on Bone Health, Vascular Calcification, and Health-Related Quality of Life in Hemodialysis Patients with Osteoporosis: A Prospective Observational Study

Background: Osteoporosis is common in hemodialysis (HD) patients, contributing to cardiovascular risks. Limited research exists on denosumab's efficacy in this group. Our study explores denosumab's effects on bone turnover markers (BTMs) and vascular calcification in chronic kidney disease-mineral bone disorder (CKD-MBD) patients. Methods: In a prospective single-center study, we investigated the effects of denosumab over 2 years on 30 HD patients from a cohort of 185. Annual assessments of bone mineral density (BMD), vascular calcification, and health-related quality of life (HRQL) were conducted and compared with an untreated group. Mineral and bone parameters were analyzed at specific intervals in the treatment group. Results: Denosumab notably raised femoral BMD in the initial year. Most bone turnover markers (BTMs) decreased, except for osteocalcin. Changes in T50 correlated with BTMs. Pre-denosumab supplementation of calcium and vitamin D helped manage mineral imbalances. Post denosumab, parathyroid hormone (PTH) levels increased initially, stabilizing after 3 months. No significant changes occurred in vascular calcification or HRQL. Conclusions: Denosumab exhibited varying effects on BMD improvement, with a stronger impact in the first year that diminished in the second year. Early PTH monitoring was crucial, and extending the administrative period may enhance BMD outcomes compared to the general population.

Long-term effects of denosumab on bone mineral density and turnover markers in patients undergoing hemodialysis

INTRODUCTION

Denosumab, a fully human anti-RANKL monoclonal antibody, is a widely used osteoporosis treatment that is increasingly being used in patients undergoing dialysis; however, its long-term efficacy and safety in these patients remain unknown.

MATERIALS AND METHODS

This observational study comprised individuals aged ≥ 20 years undergoing hemodialysis and receiving denosumab. After denosumab administration, we analyzed the long-term changes in bone mineral density (BMD) and levels of bone turnover markers (BTMs) and calcium.

RESULTS

The study included 45 patients who have been receiving denosumab for a median duration of 3.8 (interquartile range, 2.5-6.7) years. Tartrate-resistant acid phosphatase 5b (TRACP-5b) levels decreased from a median of 595 (434-778) mU/dL at baseline to 200 (141-430) mU/dL after 6 months of denosumab administration (P < 0.001) and remained low thereafter. Similarly, bone-specific alkaline phosphatase (BAP) levels decreased from a median of 18.2 (15.9-25.8) μg/L at baseline to 12.4 (9.9-15.6) μg/L after 6 months (P < 0.001) and remained low thereafter. Meanwhile, BMD, as assessed with dual energy X-ray absorptiometry and measured at the distal 1/3 of the radius, did not decrease (0.465 ± 0.112 g/cm2 at baseline vs. 0.464 ± 0.112 g/cm2 after administration; P = 0.616). Regarding hypocalcemia, corrected calcium levels reached were the lowest at 7 days after administration and normalized within 30 days.

CONCLUSION

The study showed long-term suppression of TRACP-5b and BAP levels and sustaining BMD after denosumab administration over an extended period in patients undergoing hemodialysis.