Osteoporosis in older persons: current pharmacotherapy and future directions

Bone healing study of alendronate combined with enoxaparin sodium bone cement in rabbits with bone defects

BACKGROUND

To observe the effect of enoxaparin sodium-polymethyl methacrylate (ES-PMMA) bone cement supplemented with alendronate (AN) on bone repair of bone defects in New Zealand rabbits.

METHODS

Twenty-seven New Zealand rabbits were randomly divided into ES/AN, ES-PMMA and PMMA groups, with a total of 27 New Zealand rabbits. The drugs loaded in 40 g bone cement powder were as follows: ES/AN group 8000 AxaIU enoxaparin (ES) and 200 mg alendronate (AN), ES-PMMA group 8000 AxaIU enoxaparin (ES), PMMA group without drugs. A bone defect model with a length of 10 mm and a diameter of 5 mm was made from the left tibia of rabbits, and the prepared bone cement was placed in the tibia defect. At 4 weeks, 8 weeks and 12 weeks after the operation, 3 rabbits in each group were sacrificed, and left tibia samples were collected for histological scoring, HE staining and Masson staining. Bone mineral density and new bone volume were measured by imaging, and the related data were processed by one-way ANOVA and least significance difference (LSD) post hoc test.

RESULTS

(1) Bone mineral density (BMD, mg/mm3) around the bone defect: at the 4th week, BMD in the ES/AN group was higher than that in the PMMA group; at the 8th week, the BMD in the ES/AN group was significantly higher than that in the other two groups; and at the 12th week, the BMD in the ES/AN group was significantly higher than that in the other two groups. (2) New bone volume (BV, mm3): at the 4th week, BV in the ES/AN group was significantly higher than that in the other two groups, BV in the ES/AN group was significantly higher than that in the other two groups at the 8th and 12th weeks, and BV in the ES-PMMA group was higher than that in the PMMA group. (3) Histological score: at the 4th and 8th weeks, the histological score of the ES/AN group was higher than that of the PMMA group, and at the 12th week, the histological score of the ES/AN group was higher than that of the other two groups. (4) Cortical bone thickness (μm): at the 4th, 8th and 12th weeks, the cortical bone thickness in the ES/AN group was higher than that in the other two groups, and the cortical bone thickness in the ES-PMMA group was higher than that in the PMMA group. (5) The percentage of mature area of new bone in the ES/AN group was higher than that in the other two groups at the 4th week, and at the 8th and 12th weeks, the percentage of mature area of new bone in the ES/AN group and ES-PMMA group was significantly higher than that in the PMMA group.

CONCLUSION

(1) Enoxaparin sodium bone cement supplemented with alendronate was superior to enoxaparin sodium bone cement and PMMA bone cement in promoting bone repair of tibial bone defects in New Zealand rabbits. (2) Enoxaparin sodium bone cement is superior to PMMA bone cement in promoting bone repair, showing a certain osteogenic potential.

Osteosarcopenia School

Osteosarcopenia has been proposed as a syndrome in a subset of frail individuals at higher risk of falls, fractures and institutionalization. In this paper, we will go over the translational aspects of sarcopenia and osteoporosis research and highlight outcomes from different interventions. In addition, preventative measures and therapeutic interventions that can benefit both muscle and bone simultaneously will be analysed also. A new holistic concept called Osteosarcopenia School will be presented. This new concept is based on counselling and education of patients as part of a rehabilitation program, aiming to reduce the risk of social isolation, falls and fractures, and subsequent disability through muscle strengthening and balance training. In this patient group, the combination of pharmaceutical treatments and specific exercise programmes are essential to counteract the consequences of osteosarcopenia. Finally, educational programmes targeting patient functionality through social reintegration may have a substantial impact on their daily living activities and overall quality of life.

Long-term pretreatment with alendronate inhibits calvarial defect healing in an osteoporotic rat model

INTRODUCTION

This study aimed to observe the effects of long-term alendronate pretreatment on the healing of osteoporotic calvarial defects, and further investigate the effect of alendronate combined with once-weekly parathyroid hormone following 12 weeks of alendronate treatment in ovariectomized rats.

MATERIALS AND METHODS

Thirty 3-month-old female rats were ovariectomized, and 24 rats received alendronate for 12 weeks. Then, a critical defect was created in the calvaria of all animals. Immediately after osteotomy, the animals received one of five treatments for 8 weeks: (1) continuation of vehicle (group E), (2) alendronate followed by vehicle (group A), (3) continuation of alendronate (group B), (4) alendronate followed by once-weekly parathyroid hormone alone (group C), or (5) continuation of alendronate combined with once-weekly parathyroid hormone (group D). Calvarial defect healing was assessed using dual-energy X-ray absorptiometry, micro-computed tomography, histology, and sequential fluorescence labeling.

RESULTS

Group E showed a significantly higher volume of newly formed bone than groups A, B, C, and D. Evidence of new dense bone formation in group E was observed histologically. In addition, the immunohistochemical expression of runt-related transcription factor 2 was increased in group E but inhibited in groups A, B, C, and D. Sequential immunofluorescence also showed inhibited mineral apposition in groups A, B, C, and D compared with group E.

CONCLUSION

The present study shows that long-term pretreatment with alendronate inhibited calvarial defect healing in osteoporotic rats, and this effect could not be reversed by stopping alendronate, switching to parathyroid hormone, or combining with once-weekly parathyroid hormone.

Postoperative bisphosphonate do not significantly alter the fusion rate after lumbar spinal fusion: a meta-analysis

Background

To evaluate the effect of postoperative BP treatment on improving the fusion rate after lumbar spinal fusion surgery by performing a meta-analysis of randomized controlled trials (RCTs) and other comparative cohort studies.

Methods

A comprehensive search of PubMed, EMBASE, the Web of Science, and the Cochrane Central Register of Controlled Trials was performed for RCTs and other comparative cohort studies on the effect of BP treatment on improving the fusion rate after lumbar spinal fusion surgery. The primary outcome measures were the number of patients with bone formation grades A, B, and C at 12 months of follow-up; fusion rates at 12 and 24 months of follow-up; vertebral compression fracture (VCF) at 12 and 24 months of follow-up; pedicle screw loosening at 24 months of follow-up; and cage subsidence, the Oswestry disability index (ODI), and the visual analogue score (VAS) at 12 months of follow-up. The final search was performed in July 2020.

Results

Seven studies with 401 patients were included. Compared with the placebo, BP treatment did not significantly alter the number of patients with bone formation grades A, B, and C, or the VAS at the 12-month follow-up or the fusion rates at the 12- and 24-month follow-ups. In addition, compared with the placebo, BPs significantly reduced the risks of VCF at the 12- and 24-month follow-ups, pedicle screw loosening at the 24-month follow-up, and cage subsidence and the ODI at the 12-month follow-up.

Conclusions

Postoperative BPs do not clearly improve bone formation and the fusion rate, but they reduce VCF, cage subsidence, and loosening of pedicle screws after lumbar fusion surgery compared with the control treatment.

The Efficacy and Safety of Bisphosphonates for Osteoporosis in Women Older Than 65 Years: A Meta-Analysis

BACKGROUND

Osteoporosis presents a major threat to the health of women older than 65 years. Bisphosphonates (BPs) are now the principal class of medications for osteoporosis.

OBJECTIVE

To evaluate the efficacy and safety of BPs in women older than 65 years.

METHODS

A comprehensive search in the PubMed, EMBASE, Web of Science and Cochrane Central databases was undertaken for randomized controlled trials (RCTs) on the efficacy and safety of BPs in women older than 65 years. The primary outcome measures were the change in bone mass density (BMD), serum bone turnover marker levels, fracture rate and the adverse effect (AE) rate. The final search was performed in August 2019.

RESULTS

Seven RCTs were included. A total of 23287 patients met the inclusion criteria. BPs significantly increased the BMD of the posteroanterior (PA) spine, lateral spine and femoral neck, and reduced the fracture, vertebrate fracture and hip fracture rates in women older than 65 years. In addition, BPs increased the risks for pyrexia, myalgia, arthralgia, headache and influenza-like symptoms and had no statistical effect on any AEs, any serious AEs, discontinuation due to AEs, oesophagitis, any upper gastrointestinal adverse event, atrial fibrillation and myocardial infarction occurrence in women older than 65 years. Finally, intravenous BPs reduced hip fracture risk but increased AEs in women older than 65 years.

CONCLUSION

Despite the fact that AEs significantly increased after drug delivery, BPs are highly effective and safe for managing osteoporosis in women older than 65 years. Zoledronic acid caused an increased rate of AEs in women older than 65 years, but these AEs seemed to be mild to moderate. In addition, the hip fracture rate in women older than 80 years old treated with BPs was different than that in the other included patients. Therefore, doctors may prescribe BPs for women older than 65 years in order to increase BMD, and AEs and hip fractures in women older than 80 years should be given attention.

The Effect of Bisphosphonates on Managing Osteoporosis After Spinal Cord Injury: A Meta-Analysis

BACKGROUND

The increased bone loss after spinal cord injury (SCI) is associated with an increase in the morbidity and mortality of fragility fractures, which can constitute a substantial cost to health care systems. Bisphosphonates (BPs) are now the principal class of medications used for osteoporosis.

OBJECTIVE

To demonstrate the effect of BPs on treating osteoporosis after SCI.

METHODS

A comprehensive search in PubMed, EMBASE, Web of Science and Cochrane Central databases was undertaken for randomized controlled trials (RCTs), exploring the effect of BPs on osteoporosis after SCI. The primary outcome measures were the BMD of different locations, serum bone turnover marker levels, serum biochemistry marker levels and adverse effect (AE) risks. The final search was performed in September 2019. Reporting was carried out according to PRISMA Guidelines.

RESULTS

Six RCTs were included. A total of 147 patients met the inclusion criteria. BPs were found to statistically prevent bone loss in the total hip, femoral neck and trochanter at the 6- and 12-month follow-up points and to increase the BMD of the lumbar spine at the 12-month follow-up time point. BPs had no clear effect on serum PINP or serum calcium levels at the 12-month follow-up time point.

CONCLUSION

BP therapy may prevent bone loss in the lumbar spine and hip when administered early after SCI and has relatively high safety.

Bisphosphonates Can Maintain Periprosthetic Bone Mass Density after Total Hip Replacement, with Controversy in Region of Interest 5

BACKGROUND

Total hip replacement (THR) is the standard surgical treatment of hip diseases. Periprosthetic bone mass density (BMD) loss may be a cause for revision surgery. Bisphosphonates (BPs) are now the principal class medications for osteoporosis.

OBJECTIVE

To demonstrate the effect of BPs on treating periprosthetic osteoporosis after THR via a meta-analysis of randomized controlled trials (RCTs).

METHODS

A comprehensive search of PubMed, EMBASE, the Web of Science and the Cochrane Central Register of Controlled Trials was performed for RCTs on the effect of BPs on treating periprosthetic osteoporosis after THR and clinical outcomes relative to controls. The primary outcome measures were the change in BMD in each region of interest (ROI), the change in serum bone turnover marker levels, the change in functional parameters and the risk of adverse effects (AEs). The final search was performed in March, 2020.

RESULTS

Nine RCTs were included. A total of 359 patients met the inclusion criteria. BPs can clearly maintain periprosthetic BMD in ROIs at 1, 2, 3, 4, 6 and 7 at 6, 12 and 24 months. In addition, BPs can clearly decrease serum procollagen type 1 N-terminal propeptide (P1NP) levels at 12 months. There was no significant difference in the risk of AEs between the BP and control groups; however, BPs can cause more patients to decline participation.

CONCLUSION

BPs can effectively maintain overall periprosthetic BMD, but BMD in ROI 5 remains controversial. In addition, the safety of BPs is relatively high, but the compliance may be relatively low.

Alendronate release from calcium phosphate cement for bone regeneration in osteoporotic conditions

Osteoporosis represents a major health problem in terms of compromising bone strength and increasing the risk of bone fractures. It can be medically treated with bisphosphonates, which act systemically upon oral or venous administration. Further, bone regenerative treatments in osteoporotic conditions present a challenge. Here, we focused on the development of a synthetic bone substitute material with local diminishing effects on osteoporosis. Composites were created using calcium phosphate cement (CPC; 60 wt%) and polylactic-co-glycolic acid (PLGA; 40 wt%), which were loaded with alendronate (ALN). In vitro results showed that ALN-loaded CPC/PLGA composites presented clinically suitable properties, including setting times, appropriate compressive strength, and controlled release of ALN, the latter being dependent on composite degradation. Using a rat femoral condyle bone defect model in osteoporotic animals, ALN-loaded CPC/PLGA composites demonstrated stimulatory effects on bone formation both within and outside the defect region.

Osteosarcopenia: where bone, muscle, and fat collide

As the world's population ages, the prevalence of chronic diseases increases. Sarcopenia and osteoporosis are two conditions that are associated with aging, with similar risk factors that include genetics, endocrine function, and mechanical factors. Additionally, bone and muscle closely interact with each other not only anatomically, but also chemically and metabolically. Fat infiltration, a phenomenon observed in age-related bone and muscle loss, is highly prevalent and more severe in sarcopenic and osteoporotic subjects. Clinically, when individuals suffer a combination of both disorders, negative outcomes such as falls, fractures, loss of function, frailty, and mortality increase, thus generating significant personal and socio-economic costs. Therefore, it is suggested that when bone mineral density loss is synchronic with decreased muscle mass, strength, and function, it should be interpreted as a single diagnosis of osteosarcopenia, which may be preventable and treatable. Simple interventions such as resistance training, adequate protein and calcium dietary intake, associated with maintenance of appropriate levels of vitamin D, have a dual positive effect on bone and muscle, reducing falls, fractures, and, consequently, disability. It is essential that fracture prevention approaches-including postfracture management-involve assessment and treatment of both osteoporosis and sarcopenia. This is of particular importance as in older persons the combination of osteopenia/osteoporosis and sarcopenia has been proposed as a subset of frailer individuals at higher risk of institutionalization, falls, and fractures. This review summarizes osteosarcopenia epidemiology, pathophysiology, diagnosis, outcomes, and management strategies.

Comparative efficacy of bisphosphonates in short-term fracture prevention for primary osteoporosis: a systematic review with network meta-analyses

Our network meta-analyses compared the efficacy of different bisphosphonates preventing fractures for primary osteoporosis. By including 36 studies, we found that zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture.

INTRODUCTION

This study was conducted in order to analyze the available evidence on the efficacy of bisphosphonates for preventing fractures.

METHODS

We considered randomized trials comparing any bisphosphonate with other bisphosphonate or placebo. We searched Cochrane Library, Embase, and PubMed and manually searched reference list of relevant articles. Pairwise and network meta-analyses were performed. The primary outcome is vertebral fracture. Secondary outcomes include nonvertebral fracture, hip fracture, wrist fracture, and any fracture.

RESULTS

Thirty-six studies were included. Significant difference was found between bisphosphonates for vertebral fracture and nonvertebral fracture (P < 0.0001 and P = 0.04, respectively). Compared with placebo, alendronate, clodronate, ibandronate, minodronate, pamidronate, risedronate, and zoledronic acid significantly prevented vertebral fracture. Zoledronic acid significantly reduced the risk of vertebral fracture, compared with alendronate, clodronate, etidronate, ibandronate, risedronate, and tiludronate (0.65 (0.46, 0.91), 0.53 (0.33, 0.86), 0.45 (0.27, 0.74), 0.52 (0.36, 0.75), 0.59 (0.42, 0.83), and 0.31 (0.21, 0.48), respectively). Compared with etidronate, clodronate and zoledronic acid significantly prevented nonvertebral fracture. Compared with alendronate, zoledronic acid significantly prevented any fracture. The possibility rankings showed that zoledronic ranked first in preventing vertebral fracture, hip fracture, and any fracture, and pamidronate ranked first in preventing nonvertebral fracture and wrist fracture. In the sensitivity analyses, zoledronic acid ranked first in preventing nonvertebral fracture, and alendronate ranked first in preventing hip fracture and wrist fracture.

CONCLUSION

Zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture. Uncertainty still remains and future studies are needed to accurately evaluate the comparative efficacy of bisphosphonates.