RETRACTED ARTICLE: Effects of antifracture drugs in postmenopausal, male and glucocorticoid-induced osteoporosis – usefulness of alendronate and risedronate

Does the use of preoperative bisphosphonates in patients with osteopenia and osteoporosis affect lumbar fusion rates? Analysis from a national spine registry

OBJECTIVE

Bisphosphonates are used to increase bone strength in treating osteopenia and osteoporosis, but their use for increasing lumbar fusion rates has been controversial. The objective of this study was to determine if preoperative treatment with bisphosphonates affects the reoperation rates for nonunions (operative nonunion rates) following lumbar fusions in patients with osteopenia or osteoporosis.

METHODS

The authors conducted a cohort study using data from the Kaiser Permanente Spine Registry. Patients (aged ≥ 50 years) with a diagnosis of osteopenia or osteoporosis who underwent primary elective lumbar fusions for degenerative disc disease, deformity, or spondylolisthesis were included in the cohort. Repeated spinal procedures at the index lumbar levels were noted through chart review. Reoperations for symptomatic nonunions (operative nonunions), time to nonunion, and the nonunion spine level(s) were also identified. The crude 2-year cumulative incidence of operative nonunions was calculated as 1 minus the Kaplan-Meier estimator. Cox proportional hazard regression was used to evaluate the association between preoperative bisphosphonate use and operative nonunion after adjustment for covariates. Analysis was stratified by osteopenia and osteoporosis diagnosis.

RESULTS

The cohort comprised 1040 primary elective lumbar fusion patients, 408 with osteopenia and 632 with osteoporosis. Ninety-seven (23.8%) patients with osteopenia and 370 (58.5%) patients with osteoporosis were preoperative bisphosphonate users. For the osteopenia group, no operative nonunions were observed in patients with preoperative bisphosphonate, while the crude 2-year incidence was 2.44% (95% CI 0.63–4.22) in the nonuser group. For the osteoporotic group, after adjustment for covariates, no difference was observed in risk for operative nonunions between the preoperative bisphosphonate users and nonusers (HR 0.96, 95% CI 0.20–4.55, p = 0.964).

CONCLUSIONS

To the authors’ knowledge, this study presents one of the largest series of patients with the diagnosis of osteopenia or osteoporosis in whom the effects of preoperative bisphosphonates on lumbar fusions were evaluated using operative nonunion rates as an outcome measure. The results indicate that preoperative bisphosphonate use had no effect on the operative nonunion rates for patients with osteoporosis. Similar indications were not confirmed in osteopenia patients because of the low nonunion frequency. Further studies are warranted to the determine if preoperative and postoperative timing of bisphosphonate use has any effect on lumbar fusion rates.

Circular RNA atlas in osteoclast differentiation with and without alendronate treatment

BACKGROUND

Alendronate (AL) is the most widely used bisphosphonate in the treatment of osteoporosis (OP). However, the role of circular RNAs (circRNAs) in the treatment of OP with AL remains unclear.

METHODS

In this study, we showed that osteoclast (OC) precursors (OPCSs) could be induced into OCs with macrophage colony-stimulating factor (MCSF) and receptor activator of nuclear factor-κB ligand (RANKL) treatment. Subsequently, the OCs were treated with AL. OC differentiation-related biomarkers including RANK, tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CTSK) were analyzed with TRAP staining, quantitative real-time (qPCR), and western blotting. Differentially expressed circRNAs (DECs) were identified among the OPCS, OC, and OC + AL groups. In addition, the expression levels of 10 DECs related to OC differentiation were verified by qPCR.

RESULTS

TRAP staining showed that MCSF and RANKL treatment effectively induced OPCSs to differentiate into OCs. In addition, qPCR and western blot analysis revealed that the three biomarkers of OC (RANK, TRAP, and CTSK) were expressed significantly more in the OC group than those in the OPCS group. In contrast, the mRNA and protein expression levels of these three biomarkers decreased significantly in OCs treated with AL compared with those non-treated OCs. GO analysis of the DECs in the OPCS group vs. the OC group revealed that their functions were mainly related to cell, cell part, binding, and single-organism terms. KEGG analysis of the top 20 DECs in a comparison between the OPCS and OC groups showed that genes involved in mitogen-activated protein kinase signaling were the most common. Results of functional analyses of DECs in an OC vs. OC + AL comparison were similar to those in the OPCS vs. OC comparison. Finally, qPCR showed that, in the OC + AL vs. OC group comparison, the expression levels of seven and three DECs significantly decreased and increased, respectively.

CONCLUSIONS

Having successfully induced OPCSs to differentiate into OCs, we showed that AL suppresses the differentiation of OPCS into OC and that 10 DECs were involved in the regulation of this process. This indicates that these DECs might be important to the treatment of OP.

Effect of bisphosphonate on the prevention of bone loss in patients with gastric cancer after gastrectomy: A randomized controlled trial

BACKGROUND

Bone loss is highly prevalent after gastrectomy in gastric cancer patients. Therefore, the efficacy of medical treatment should be evaluated in patients undergoing gastrectomy.

METHODS

We conducted an unblinded, randomized controlled trial of patients who underwent gastrectomy to treat gastric cancer. The intention-to-treat participants (n = 107) were randomly assigned to receive either alendronate at a weekly dose of 70 mg and daily elemental calcium (500 mg) with cholecalciferol (1000 IU) or daily elemental calcium (500 mg) with cholecalciferol (1000 IU) only. The primary endpoint was defined by the changes in bone mineral density of four measurement sites: the lumbar spine, femur neck, total hip, and trochanter. Changes in bone turnover markers, osteocalcin and collagen I carboxyterminal telopeptide were also observed.

RESULTS

At baseline, there were no differences between the two groups in bone mineral density. In the lumbar spine and trochanter, there were no significant percentage changes compared with the baseline in the alendronate group, but a significant decrease was noted in the control group (p < 0.001 for both lumbar spine and trochanter). In the femur neck and total hip, a larger decrease was observed compared with the baseline in the control group (p < 0.001 for both femur neck and total hip). Significant percentage increases in serum osteocalcin compared with baseline were noted in the control group (p for trend <0.001), but there was no change in the alendronate group (p for trend = 0.713). Collagen I carboxyterminal telopeptide significantly declined in the alendronate group over 12 months (p for trend <0.001).

CONCLUSIONS

Prevention and treatment with bisphosphonate effectively reduces bone loss by suppressing bone resorption in gastric cancer patients undergoing gastrectomy.

Quality of prescribing predicts hospitalisation in octogenarians: life and living in advanced age: a cohort study in New Zealand (LiLACS NZ)

BACKGROUND

Prescribing for older people is complex, and many studies have highlighted that appropriate prescribing in this cohort is not always achieved. However, the long-term effect of inappropriate prescribing on outcomes such as hospitalisation and mortality has not been demonstrated. The aim of this study was to determine the level of potentially inappropriate prescribing (PIP) for participants of the Life and Living in Advanced Age: A Cohort Study in New Zealand (LiLACS NZ) study at baseline and examine the association between PIP and hospitalisation and mortality at 12-months follow-up.

METHODS

PIP was determined using STOPP/START. STOPP identified potentially inappropriate medicines (PIMs) prescribed, START identified potential prescribing omissions (PPOs). STOPP/START were applied to all LiLACS NZ study participants, a longitudinal study of ageing, which includes 421 Māori aged 80-90 years and 516 non-Māori aged 85 years. Participants' details (e.g. age, sex, living arrangements, socioeconomic status, physical functioning, medical conditions) were gathered by trained interviewers. Some participants completed a core questionnaire only, which did not include medications details. Medical conditions were established from a combination of self-report, review of hospital discharge and general practitioner records. Binary logistic regression, controlled for multiple potential confounders, was conducted to determine if either PIMs or PPOs were associated with hospital admissions and mortality (p < 0.05 was considered significant).

RESULTS

Full data were obtained for 267 Māori and 404 non-Māori. The mean age for Māori was 82.3(±2.6) years, and 84.6(±0.53) years for non-Māori. 247 potentially inappropriate medicines were identified, affecting 24.3% Māori and 28.0% non-Māori. PIMs were not associated with 12-month mortality or hospitalisation for either cohort (p > 0.05; adjusted models). 590 potential prescribing omissions were identified, affecting 58.1% Māori and 49.0% non-Māori. PPOs were associated with hospitalisation (p = 0.001 for Māori), but were not associated with risk of mortality (p > 0.05) for either cohort within the 12-month follow-up (adjusted models).

CONCLUSION

PPOs were more common than PIMs and were associated with an increased risk of hospitalisation for Māori. This study highlights the importance of carefully considering all indicated medicines when deciding what to prescribe. Further follow-up is necessary to determine the long-term effects of PIP on mortality and hospitalisation.

Efficacy and safety of bisphosphonates in management of low bone density in inflammatory bowel disease: A meta-analysis

This study aims to determine whether bisphosphonates are safe, as well as effective against bone mineral loss in inflammatory bowel disease (IBD). A computerized search of electronic databases from 1966 to 2016 was performed. Randomized controlled trials (RCTs) were included in this review to evaluate the role of bisphosphonates in the management of osteoporosis in IBD patients. A revised 7-point Jadad scale was used to evaluate the quality of each study. Overall, 13 RCTs and 923 patients met the inclusion criteria of this meta-analysis. The result showed that bisphosphonates decreased bone mass density (BMD) loss at the lumbar spine (P = 0.0002), reduced the risk of new fractures (P = 0.01), and retained the similar adverse events (P = 0.86). Bisphosphonates may provide protection and safety against bone mineral loss in IBD patients.

RETRACTED: Efficacy of bisphosphonates against hip fracture in elderly patients with stroke and Parkinson diseases: meta-analysis of randomized controlled trials

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. This paper includes a meta-analysis based on papers by another author group that have since been retracted. Researchers can be misled by reading this paper, thus we have retracted it.

Risedronate inhibits bone marrow mesenchymal stem cell adipogenesis and switches RANKL/OPG ratio to impair osteoclast differentiation

BACKGROUND

Osteoporosis is accompanied by an increase in bone marrow adipose tissue. Bone marrow adipogenesis has emerged as a therapeutic target for prevention of bone loss. Amino-bisphosphonates have been widely used for treatment of osteoporosis, but the mechanism through which amino-bisphosphonates inhibit osteoporosis remains unclear. The purpose of this study is to investigate the effects of bisphosphonates on bone marrow adipogenesis and the pro-osteoclastic factors produced by adipocytes in bone marrow microenvironment.

MATERIALS AND METHODS

Human mesenchymal stem cells were obtained and purified from six volunteer donors. Each sample of cells was treated by increasing concentrations of risedronate with or without adipogenic induction for 14 d, and then droplets of the differentiated adipocytes were analyzed. The level of receptor activator of nuclear factor-κB ligand and osteoprotegerin, as well as pro-osteoclastic inflammatory factors interleukin-1, interleukin-6, and tumor necrosis factor α produced by adipocytes were evaluated by Western blot and ELISA assay. Moreover, the effect of risedronate on the activity of mammalian target of rapamycin complex 1, a key Ser/Thr kinase for initiation of adipocyte differentiation, was investigated.

RESULTS

Risedronate not only dose-dependently inhibited the bone marrow adipogenesis from human mesenchymal stem cells but also suppressed receptor activator of nuclear factor-κB ligand, not osteoprotegerin, expression in differentiated adipocytes, as well as pro-osteoclastic inflammatory factors. Furthermore, the activity of mammalian target of rapamycin complex 1 was suppressed by risedronate.

CONCLUSION

Our findings that risedronate influences the crosstalk between bone marrow adipocyte-osteoclast represent a novel mechanism for the anti-osteoporotic effects of risedronate.

Post hoc analysis of a single IV infusion of zoledronic acid versus daily oral risedronate on lumbar spine bone mineral density in different subgroups with glucocorticoid-induced osteoporosis

This study summarizes the treatment effect of zoledronic acid infusion on lumbar spine bone mineral density in different subgroups with glucocorticoid-induced osteoporosis. Zoledronic acid is significantly more effective than risedronate in increasing lumbar spine (LS) bone mineral density (BMD) in both prevention and treatment of glucocorticoid-induced osteoporosis. Introduction In patients on glucocorticoids, a single zoledronic acid infusion significantly increased BMD versus daily oral risedronate. We assessed treatment effect on LS BMD in different patient subgroups at month 12 that contributed to the risk of osteoporosis in addition to glucocorticoids. Methods Patients randomized to a single IV infusion of zoledronic acid 5 mg or risedronate (5 mg/day) and stratified based on glucocorticoids duration [treatment (>3 months) and prevention (≤ 3 months) subpopulations]were subgrouped by age; gender; menopausal status in women; dose and duration of prednisone during the trial; and baseline serum 25-OH vitamin D, LS BMD T-score, creatinine clearance, and concomitant medication use. Results At month 12, zoledronic acid significantly increased LS BMD versus risedronate in patients ≤ 74 years (P<0.05) in the treatment and 65-74 years (P = 0.0008) in the prevention subpopulation. At month 12, zoledronic acid significantly increased LS BMD versus risedronate in both subpopulations irrespective of gender (all P<0.05), cumulative prednisone dose (all P<0.01), and postmenopausal status (all P<0.05). In premenopausal women, in both subpopulations, zoledronic acid significantly increased total hip BMD (all P<0.05) versus risedronate at month 12 but not LS BMD. Osteoporotic patients in the prevention (P=0.0189) and osteopenic patients in the treatment subpopulation (P=0.0305) showed significant LS BMD increases with zoledronic acid versus risedronate at month 12. Conclusions This post hoc analysis suggests that zoledronic acid is significantly more effective than risedronate in increasing LS BMD in prevention and treatment of glucocorticoid-induced osteoporosis across a wide range of patients.

Low-magnitude whole body vibration does not affect bone mass but does affect weight in ovariectomized rats

Mechanical loading has stimulating effects on bone architecture, which can potentially be used as a therapy for osteoporosis. We investigated the skeletal changes in the tibia of ovariectomized rats during treatment with whole body vibration (WBV). Different low-magnitude WBV treatment protocols were tested in a pilot experiment using ovariectomized rats with loading schemes of 2 × 8 min/day, 5 days/week (n = 2 rats per protocol). Bone volume and architecture were evaluated during a 10 week follow-up using in-vivo microcomputed tomography scanning. The loading protocol in which a 45 Hz sine wave was applied at 2 Hz with an acceleration of 0.5g showed an anabolic effect on bone and was therefore further analyzed in two groups of animals (n = 6 each group) with WBV starting directly after or 3 weeks after ovariectomy and compared to a control (non-WBV) group at 0, 3, 6 and 10 weeks' follow-up. In the follow-up experiment the WBV stimulus did not significantly affect trabecular volume fraction or cortical bone volume in any of the treatment groups during the 10 week follow-up. WBV did reduce weight gain that was induced as a consequence of ovariectomy. We could not demonstrate any significant effects of WBV on bone loss as a consequence of ovariectomy in rats; however, the weight gain that normally results after ovariectomy was partly prevented. Treatment with WBV was not able to prevent bone loss during induced osteoporosis.

Alendronate is more effective than elcatonin in improving pain and quality of life in postmenopausal women with osteoporosis

A randomized controlled trial was performed to compare the short-term effects of alendronate (ALN) and ECT on pain and quality of life (QOL) in postmenopausal women with osteoporosis. Back pain and QOL [Short-Form Health Survey (SF-8)] significantly improved at 1, 3, and 6 months in both groups, with greater improvements in the ALN group than in the ECT group. These results suggested that ALN reduced back pain and improved QOL more markedly than ECT in postmenopausal osteoporotic women with back pain.

INTRODUCTION

Intramuscular ECT is known to reduce pain via the central nervous system. A multicenter randomized controlled trial was performed to compare the short-term effects of ALN and ECT on pain and QOL in postmenopausal women with osteoporosis.

METHODS

One hundred and 94 postmenopausal osteoporotic women with back pain (mean age 79.8 years, range 60-96 years) were randomly divided into two groups: the ALN group (35 mg weekly) and the ECT group (intramuscular 20 units a week). The duration of the study was 6 months. The trial was completed in 97 (100%) women of the ALN group and 96 (99.0%) women of the ECT group. Urinary levels of cross-linked N-terminal telopeptide of type I collagen (NTX), serum alkaline phosphatase (ALP), face scale score (FSS, back pain), and SF-8 (QOL) were monitored.

RESULTS

Urinary NTX levels significantly decreased at 3 months in the ALN group, but not in the ECT group. Serum ALP levels significantly decreased at 6 months in the both groups, with a greater reduction in the ALN group. The FSS and SF-8 significantly improved at 1, 3, and 6 months in both groups, with greater improvements in the ALN group than in the ECT group.

CONCLUSIONS

ALN suppressed bone turnover, reduced back pain, and improved QOL more markedly than ECT in postmenopausal osteoporotic women with back pain.

Efficacy of oral bisphosphonates for preventing hip fracture in disabled patients with neurological diseases: a meta-analysis of randomized controlled trials among the Japanese population

OBJECTIVE

Neurological diseases such as amyotrophic lateral sclerosis (ALS), stroke, and Parkinson's disease cause disability and immobilization that increases the risk of hip fracture. The purpose of the present study was to clarify the efficacy of oral bisphosphonates for preventing hip fracture in disabled patients with such neurological diseases.

METHODS

A literature search (PubMed) was done from 1995 to the present for randomized controlled trials (RCTs), and a meta-analysis was conducted.

RESULTS

Seven RCTs met the criteria, including two of etidronate (ALS and stroke), two of alendronate (stroke and Parkinson's disease), and three of risedronate (stroke and Parkinson's disease). All of the RCTs were performed on Japanese patients. According to the results of pooled data analysis, the relative risk (95% confidence interval) of hip fracture in patients receiving etidronate, alendronate, and risedronate treatment compared with placebo or active control treatment was 0.16 (0.03-0.87), 0.29 (0.10-0.80), and 0.24 (0.10-0.58), respectively, suggesting a reduction of risk by more than 70% with oral bisphosphonates. There was no statistical evidence of heterogeneity among RCTs, and publication bias was not identified by the funnel plot and Begg's rank correlation test. No severe adverse events due to oral bisphosphonate treatment were reported.

LIMITATION

It remains uncertain whether the findings are relevant for Western patients with an increased risk of hip fracture due to neurological diseases.

CONCLUSION

A meta-analysis of RCTs suggested that oral bisphosphonate treatment prevents hip fracture in disabled Japanese patients with neurological diseases, including ALS, stroke, and Parkinson's disease. Oral bisphosphonate treatment was well tolerated by such patients.

Evaluation of bone remodelling parameters after one year treatment with alendronate in postmenopausal women with osteoporosis

Antiresorptive agents are widely used to treat osteoporosis. Both reduction in bone turnover and increase in BMD may be necessary to decrease the fracture risk. The aim of the study was to evaluate the effects of aledronate on bone turnover markers and bone mineral density in postmenopausal women with osteoporosis. The study involved a group of 56 postmenopausal women with osteoporosis treated with alendronate (70 mg) weekly at the Institute of Nuclear Medicine Clinical Center University of Sarajevo during a 12-months period. Bone mineral density (BMD) at lumbar spine and proximal femur and bone turnover markers (serum β-CrossLaps, urinary N-telopeptides of type I collagen (NTx), total serum alkaline phosphatase (AP) and serum osteocalcin) were measured at baseline and after 12 months of the treatment with aledronate. BMD values significantly increased both at lumbar spine by 13.46% and proximal femur by 21.96% during the study period (-3.12±0.24 vs. -2.7±0.19 and -2.55±0.2 vs. -1.99±0.19 respectively; p<0.001). Bone turnover markers significantly decreased during the study period; C-terminal telopeptides of type I collagen fragment (β-CrossLaps) 49.0% (0.51±0.05 vs.0.26±0.028 ng/mL), NTX 33.4% (48.3±4.9 vs.32.15±3.25 nMBCE/mM Cr), AP 24.3% (81.1±5.2 to 61.43±5.2 IU/L) and serum osteocalcin by 29.7% (34.3±2.65 to 24.1±1.36 ng/mL)(p<0.001). Alendronate treatment increased BMD and reduced the level of bone turnover markers. Therefore, the treatment with aledronate during 12 months period can be recommended in postmenopausal women with osteoporosis.

Effect of alendronate on bone mineral density and bone turnover markers in post-gastrectomy osteoporotic patients

Alendronate decreases the urinary levels of cross-linked N-terminal telopeptides of type I collagen (NTX; about 45% at 3 months) and serum levels of alkaline phosphatase (ALP; about 27% at 24 months), leading to an increase in lumbar spine bone mineral density (BMD; about 9% at 24 months) in postmenopausal Japanese women with osteoporosis. However, the effectiveness of oral bisphosphonates on osteoporosis remains to be established in patients who have undergone a gastrectomy. The objective of the present case series study was to examine the effect of alendronate on BMD and bone turnover markers in post-gastrectomy osteoporotic patients. Sixteen patients (3 men and 13 postmenopausal women) with osteoporosis, who had undergone a gastrectomy (mean age: 69.1 years), were recruited in our outpatient clinic. All the patients were treated with alendronate (5 mg daily or 35 mg weekly) for 24 months. The effects of alendronate on lumbar spine (women) or total hip (men) BMD and urinary NTX and serum ALP levels were examined. A total or partial gastrectomy had been performed for eight patients each. The mean duration after surgery was 16.0 years. With alendronate therapy, urinary NTX levels significantly decreased at 3 months (-27.0%). Serum ALP levels decreased (-12.1%) and lumbar spine BMD increased (+5.2%), but total hip BMD did not significantly change (+0.6%) at 24 months. No severe adverse events were observed, and alendronate therapy was well tolerated. These results suggest that alendronate mildly increases lumbar spine BMD by mildly reducing bone turnover in osteoporotic patients after a gastrectomy.

Effects of short-term combined treatment with alendronate and elcatonin on bone mineral density and bone turnover in postmenopausal women with osteoporosis

The antiresorptive drug elcatonin (ECT) is known to relieve pain in postmenopausal women with osteoporosis. A prospective open-labeled trial was conducted to compare the effects of short-term combined treatment with alendronate (ALN) and ECT on bone mineral density (BMD) and bone turnover with those of single treatment with ALN in postmenopausal women with osteoporosis. Two hundred and five postmenopausal osteoporotic women (mean age: 70 years) were recruited in our outpatient clinic. Forty-six women with back pain were treated with ALN and ECT (intramuscular, 20 units a week), and 159 women without obvious back pain were treated with ALN alone. The lumbar BMD, urinary levels of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of alkaline phosphatase (ALP) were measured during the six-month treatment period. The baseline characteristics, except for age, body weight and number of patients with prevalent vertebral fractures, were not significantly different between the two groups. The mean increase rate in the lumbar BMD at six months was similar in the ALN (+4.41%) and ALN+ECT (+5.15%) groups, following similar reduction rates in urinary NTX levels (-40.2% and -43.0%, respectively, at three months) and serum ALP levels (-19.0% and -19.7%, respectively, at six months). These results were consistent even after adjustments for age, body weight, and number of patients with prevalent vertebral fractures. The present study in postmenopausal osteoporotic women confirmed that the effects of short-term combined treatment with ALN and ECT on lumbar BMD and bone turnover in patients with back pain appeared to be comparable to those of single treatment with ALN in patients without obvious back pain.

Role of sport and exercise in the maintenance of female bone health

Osteoporosis most commonly affects postmenopausal women, placing them at a significant risk for fractures. The strategies for preventing osteoporotic fractures are maximizing peak bone mass, counteracting age- and menopause-related bone loss, minimizing the increase in spinal kyphosis, and preventing falls. Thus, the aim of sport and exercise appears to differ among ages in the maintenance of bone health in females. Given that maximizing peak bone mass is the most important strategy for preventing fractures in later life, interventions may therefore be needed before the menarche (during the growth spurt) in children. The efficacy of sport activity and exercise in all strategies has been established, although there is no evidence that sport and exercise are able to prevent hip fractures. However, sport activity and exercise across the life span of the average female should be encouraged in the maintenance of bone health.

Effects of genistein aglycone in osteoporotic, ovariectomized rats: a comparison with alendronate, raloxifene and oestradiol

Background and purpose:

Genistein aglycone positively affects bone loss in postmenopausal women, but bone quality data are still lacking. To clarify this, we investigated the effects of genistein compared with alendronate, raloxifene and oestradiol in an animal model of established osteoporosis.

Experimental approach:

Six months after ovariectomy, 96 ovariectomized (OVX) rats were divided into 8 equal groups, randomized to treatments (genistein aglycone (1 and 10 mg kg⁻¹ s.c.); alendronate (0.003 and 0.03 mg kg⁻¹ s.c.); raloxifene hydrochloride (0.05 and 0.5 mg kg⁻¹ s.c.); 17-α-ethinyl oestradiol (0.003 and 0.03 mg kg⁻¹ s.c.)) for 12 weeks. Untreated OVX (n=12) and sham OVX (n=12) were used as controls. At the beginning and end of treatment, bone mineral density (BMD) and bone mineral content (BMC) were assessed. At the end of the experiment, calcium, phosphorus, bone-alkaline phosphatase (b-ALP), collagen C-telopeptide (CTX), osteoprotegerin (OPG) and soluble receptor activator of nuclear factor-κB ligand (sRANKL) were assayed. Femurs were removed and tested for breaking strength and histology.

Key results:

Genistein (10 mg kg⁻¹) showed a greater increase in both BMD (P<0.0001 vs OVX) and BMC than all the other treatments. Moreover, genistein significantly increased breaking strength, bone quality, b-ALP (P<0.0001 vs OVX) and OPG, and reduced CTX and sRANKL compared with the other treatments at all dose levels.

Conclusions and implications:

The results strongly suggest that the genistein aglycone might be a new therapy for the management of postmenopausal osteoporosis in humans.

Osteoporosis in men

With the aging of the population, there is a growing recognition that osteoporosis and fractures in men are a significant public health problem, and both hip and vertebral fractures are associated with increased morbidity and mortality in men. Osteoporosis in men is a heterogeneous clinical entity: whereas most men experience bone loss with aging, some men develop osteoporosis at a relatively young age, often for unexplained reasons (idiopathic osteoporosis). Declining sex steroid levels and other hormonal changes likely contribute to age-related bone loss, as do impairments in osteoblast number and/or activity. Secondary causes of osteoporosis also play a significant role in pathogenesis. Although there is ongoing controversy regarding whether osteoporosis in men should be diagnosed based on female- or male-specific reference ranges (because some evidence indicates that the risk of fracture is similar in women and men for a given level of bone mineral density), a diagnosis of osteoporosis in men is generally made based on male-specific reference ranges. Treatment consists both of nonpharmacological (lifestyle factors, calcium and vitamin D supplementation) and pharmacological (most commonly bisphosphonates or PTH) approaches, with efficacy similar to that seen in women. Increasing awareness of osteoporosis in men among physicians and the lay public is critical for the prevention of fractures in our aging male population.

Hip fracture protection by alendronate treatment in postmenopausal women with osteoporosis: a review of the literature

Osteoporosis most commonly affects postmenopausal women, placing them at a significant risk of fractures. In particular, hip fractures are an important cause of mortality and morbidity among postmenopausal women. Anti-resorptive therapies that produce greater decreases in bone turnover markers together with greater increases in bone mineral density (BMD) are associated with greater reductions in fracture risk, especially at sites primarily composed of cortical bone such as the hip. Thus, treatment with potent anti-resorptive drugs like alendronate is a strategy for preventing hip fractures in postmenopausal women with osteoporosis. The purpose of this paper is to discuss the efficacy of alendronate against hip fractures and the mechanism for this anti-fracture efficacy in postmenopausal women with osteoporosis. A meta-analysis of randomized controlled trials has shown that alendronate reduces the risk of hip fractures by 55% in postmenopausal women with osteoporosis. According to the analyses of the Fracture Intervention Trial, each 1 standard deviation reduction in a 1-year change in bone-specific alkaline phosphatase (BSAP) is associated with 39% fewer hip fractures in alendronate-treated postmenopausal women, and those with at least 30% reduction in BSAP have a 74% lower risk of hip fractures relative to those with less than 30%. Alendronate is effective in reducing the risk of hip fractures across a spectrum of ages. The mechanism for this anti-fracture efficacy has been clarified; alendronate strongly suppresses bone turnover and subsequently increases hip BMD, decreases cortical porosity, improves parameters of hip structure geometry (cortical thickness, cross-sectional area, section modulus, and buckling ratio), and produces more uniform mineralization (increases the mean degree of mineralization of bone) in cortical bone. A once-weekly regimen of alendronate administration provides better patient compliance and persistence with the treatment than the once-daily dosing regimen, leading to greater efficacy against hip fractures. Thus, the efficacy of alendronate against hip fractures has been confirmed in postmenopausal women with osteoporosis, especially with a once-weekly dosing regimen.