Addition of alendronate to ongoing hormone replacement therapy in the treatment of osteoporosis: a randomized, controlled clinical trial

Does the VDR gene polymorphism influence the efficacy of denosumab therapy in postmenopausal osteoporosis?

INTRODUCTION

One of the challenges of personalized medicine is a departure from traditional pharmacology toward individualized, genotype-based therapies. Postmenopausal osteoporosis is a prevalent condition requiring intensive treatment, whose effects are measurable only after a long time, and the goal is bone fracture prevention. This study aimed to determine the influence of VDR gene variation on anti-osteoporotic one-year treatment with denosumab in 63 Polish women with postmenopausal osteoporosis.

MATERIALS AND METHODS

The correlation between bone mineral density (BMD) of the lumbar vertebral column (L1-L4) and femoral neck, and genotype distributions for the ApaI, BsmI, FokI, and TaqI variants of the VDR gene was analyzed. Bone fractures during denosumab therapy were also investigated.

RESULTS

In the case of the Bsml polymorphism, female patients with BB and Bb genotypes had statistically significantly higher values of BMD and T-score/Z-score indicators, which persisted after a year of denosumab treatment. Our results indicated that the Bsml polymorphism contributes to better bone status, and, consequently, to more efficient biological therapy. The study did not reveal significant differences between changes (delta) in BMD and genotypes for the analyzed VDR gene loci. In the entire study group, one bone fracture was observed in one patient throughout the yearlong period of denosumab therapy.

CONCLUSIONS

BB and Bb genotypes of the Bsml polymorphism of the VDR gene determine higher DXA parameter values both before and after one-year denosumab therapy in postmenopausal women with osteoporosis.

Effects of Combination Therapy of Alendronate and Hormonal Therapy on Bone Mineral Density in Postmenopausal Korean Women: Multicenter, Randomized Controlled Clinical Trial

This study evaluated the effects of combination treatment with alendronate (ALEN) and hormone therapy (HT) on bone mineral density (BMD) in postmenopausal Korean women. This multicenter, randomized, controlled clinical trial enrolled 344 postmenopausal women with low BMD. The women received HT (0.625 mg/day of conjugated equine estrogen and 2.5 mg/day of medroxyprogesterone acetate) alone or in combination with ALEN (10 mg/day) for 1 year. Changes in BMD and biochemical markers of bone turnover were evaluated. Data from 203 women (HT alone, 99; combination treatment, 104) who completed this study were analyzed. BMD at the lumbar spine and total hip increased significantly in both treatment groups after 1 year. There were no significant differences between HT alone vs. the combination of ALEN and HT in mean BMD increase at the lumbar spine (6.9% vs. 7.9%) and total hip (3.7% vs. 3.8%). Combined therapy suppressed serum osteocalcin and urinary deoxypyridinoline to a greater extent than HT alone. In conclusion, compared to HT alone, combination treatment with ALEN and HT for 1 year did not offer a benefit in BMD in postmenopausal Korean women with low BMD.

Combination Therapy of Raloxifene and Alendronate for Treatment of Osteoporosis in Elderly Women

Objectives

To evaluate and compare the efficacy and safety of the combination of raloxifene and alendronate with those of monotherapies in elderly women with osteoporosis.

Methods

Sixty-two postmenopausal women (mean age 63.5 ± 0.5 years) attending gynecologic osteoporosis clinics with established osteoporosis were randomly allocated to one of four treatment groups and monitored for 3 years. All patients enrolled in this study, including those in the control group (n = 14), received 1.0 g elemental calcium and 400 units of vitamin D per day. The raloxifene group (n = 16) received raloxifene 60 mg (Evista®) per day; alendronate group (n = 17) received low-dose (5 mg) alendronate with calcitriol 0.5 µg (Maxmarvil®) per day; and the combination therapy group (n = 15) received both raloxifene 60 mg and low-dose (5 mg) alendronate with calcitriol 0.5 µg. Bone mineral density (BMD) was measured in the lumbar spine and hip before and after 3 years of treatment.

Results

In patients who received the combined therapy, BMD increased in the lumbar spine and the hip by 7.2% (P<0.001) and 4.8% (P<0.001) at 3 years. For patients in the alendronate group, the increases were 6.7% (P<0.001) and 3.1% (P<0.01) respectively, for the raloxifene group, the increases were 4.36% (P<0.001) and 1.9% (P<0.05) in the vertebrae and femora, respectively; however, the BMD of patients in the control group decreased by 1.81% (P<0.05) and 1.6% (P<0.05), respectively, after 3 years. Patients who received the combination therapy had significantly higher BMD in both the vertebrae femora (P<0.01) in comparison to that in those treated with raloxifene or alendronate individually.

Conclusions

This 3-year randomized study showed the improved effects of alendronate and raloxifene combination on spine and hip BMD in elderly postmenopausal women with established osteoporosis.

A polymorphism at the translation start site of the vitamin D receptor gene is associated with the response to anti-osteoporotic therapy in postmenopausal women from southern Italy

The present study investigated the effect of two single nucleotide polymorphisms (SNPs) of the vitamin D receptor (VDR) gene, rs1544410 A/G and rs2228570 C/T, in modulating bone mineral density (BMD) and the response to treatment with bisphosphonates or strontium ranelate in postmenopausal osteoporosis (PMO). Four hundred eighteen postmenopausal women from Southern Italy treated with bisphosphonates or strontium ranelate for three years were enrolled and stratified according to their genotype. Changes in BMD were expressed as the delta t-score (Δt-score). Allelic frequencies for rs1544410 A/GSNP were 11.2% AA, 50.0% GA and 38.8% GG; for rs2228570 C/TSNP were 54.8% CC, 39.5% TC and 5.7% TT. TT carriers showed a lower t-score than TC and CC (both p < 0.02) genotypes and were more responsive to the therapy when compared to both TC (p < 0.02) and CC (p < 0.05) carriers. Specifically, TT carriers receiving alendronate demonstrated a significant improvement of the Δt-score compared to TC and CC (both p < 0.0001) carriers. After adjustment for confounders, the Δt-score showed evidence of a statistically significant positive association with TT in all treatments considered. Therapy response was independent of rs1544410 A/G SNP; instead, rs2228570 C/TSNP was associated with a better response to antiresorptive treatment, thus suggesting that the therapy for PMO should be personalized.

Comparative effects of teriparatide and ibandronate on spine bone mineral density (BMD) and microarchitecture (TBS) in postmenopausal women with osteoporosis: a 2-year open-label study

Treatment effects over 2 years of teriparatide vs. ibandronate in postmenopausal women with osteoporosis were compared using lumbar spine bone mineral density (BMD) and trabecular bone score (TBS). Teriparatide induced larger increases in BMD and TBS compared to ibandronate, suggesting a more pronounced effect on bone microarchitecture of the bone anabolic drug.

INTRODUCTION

The trabecular bone score (TBS) is an index of bone microarchitecture, independent of bone mineral density (BMD), calculated from anteroposterior spine dual X-ray absorptiometry (DXA) scans. The potential role of TBS for monitoring treatment response with bone-active substances is not established. The aim of this study was to compare the effects of recombinant human 1-34 parathyroid hormone (teriparatide) and the bisphosphonate ibandronate (IBN), on lumbar spine (LS) BMD and TBS in postmenopausal women with osteoporosis.

METHODS

Two patient groups with matched age, body mass index (BMI), and baseline LS BMD, treated with either daily subcutaneous teriparatide (N = 65) or quarterly intravenous IBN (N = 122) during 2 years and with available LS BMD measurements at baseline and 2 years after treatment initiation were compared.

RESULTS

Baseline characteristics (overall mean ± SD) were similar between groups in terms of age 67.9 ± 7.4 years, body mass index 23.8 ± 3.8 kg/m(2), BMD L1-L4 0.741 ± 0.100 g/cm(2), and TBS 1.208 ± 0.100. Over 24 months, teriparatide induced a significantly larger increase in LS BMD and TBS than IBN (+7.6 % ± 6.3 vs. +2.9 % ± 3.3 and +4.3 % ± 6.6 vs. +0.3 % ± 4.1, respectively; P < 0.0001 for both). LS BMD and TBS were only weakly correlated at baseline (r (2) = 0.04) with no correlation between the changes in BMD and TBS over 24 months.

CONCLUSIONS

In postmenopausal women with osteoporosis, a 2-year treatment with teriparatide led to a significantly larger increase in LS BMD and TBS than IBN, suggesting that teriparatide had more pronounced effects on bone microarchitecture than IBN.

Controversies in osteoporosis management: antiresorptive therapy for preventing bone loss: when to use one or two antiresorptive agents?

Women who have significant bone loss or a new fracture on monotherapy are considered for combination therapy. Combination therapies increase bone density more than monotherapy by targeting different parts of the osteoclast pathway.In early postmenopausal women who are symptomatic, the use of combination antiresorptives should include hormone therapy with a bisphosphonate or with bazodoxifene. In women who initially receive a weaker antiresorptive such as the SERM raloxifene, a combination with bisphosphonates and calcium supplementation is necessary to prevent bone loss. In older women over 65 years of age who often have impaired calcium absorption, the combination of calcitriol with bisphosphonates has been shown to increase bone density more than monotherapy.

The use of combination therapy in the treatment of postmenopausal osteoporosis

In recent years, there has been growing interest in the potential use of combination therapy in the management of osteoporosis in postmenopausal women. Possible regimens include sequential or combined use of anti-resorptive drugs or combinations of anabolic and anti-resorptive agents, given concurrently or in sequence. Combined therapy with anti-resorptive drugs usually produces greater increases in bone mineral density (BMD) than monotherapy but there is no evidence that this results in greater anti-fracture efficacy. The use of bisphosphonates before strontium ranelate or PTH peptides blunts the BMD response. Combined PTH and anti-resorptive therapy results in more rapid gains in spine BMD and a greater increase in hip BMD than PTH monotherapy in the first year of treatment but greater gains in both spine and hip BMD are seen with PTH monotherapy than combined therapy after 2 years of treatment. Anti-resorptive therapy after PTH therapy maintains or increases the gains in BMD. Further research is required to establish the cost-effectiveness and safety of combined and sequential regimens.

Prior treatment with vitamin K(2) significantly improves the efficacy of risedronate

Prior 8-week treatment with menatetrenone, MK-4, followed by 8-week risedronate prevented the shortcomings of individual drugs and significantly increased the strength of ovariectomized ICR mouse femur compared to the ovariectomized (OVX) controls. Neither MK-4 following risedronate nor the concomitant administration may be recommended because they brought the least beneficial effect.

INTRODUCTION

The objective of this study was to determine the best combinatory administration of risedronate at 0.25 mg/kg/day (R) with vitamin K(2) at approximately 100 microg MK-4/kg/day (K) to improve strength of osteoporotic mouse bone.

METHODS

Thirteen-week-old ICR mice, ovariectomized at 9-week, were treated for 8 weeks with R, K, or R plus K (R/K), and then, either the treatment was withdrawn (WO) or switched to K or R in the case of R and K. After another 8 weeks, the mice were killed, and mechanical tests and analyses of femur properties by peripheral quantitative computed tomography, microfocus X-ray tube computed tomography, and confocal laser Raman microspectroscopy were carried out.

RESULTS

The K to R femur turned out superior in parameters tested such as material properties, bone mineral density, BMC, trabecular structure, and geometry of the cortex. The increased cross-sectional moment of inertia, which occurred after K withdrawal, was prevented by risedronate in K to R. In addition to K to R, some properties of R to WO diaphysis and K to WO epiphysis were significantly better than OVX controls.

CONCLUSION

Prior treatment with MK-4 followed by risedronate significantly increased femur strength in comparison to the OVX controls.

Progress in osteoporosis and fracture prevention: focus on postmenopausal women

In the past decade, we have witnessed a revolution in osteoporosis diagnosis and therapeutics. This includes enhanced understanding of basic bone biology, recognizing the severe consequences of fractures in terms of morbidity and short-term re-fracture and mortality risk and case finding based on clinical risks, bone mineral density, new imaging approaches, and contributors to secondary osteoporosis. Medical interventions that reduce fracture risk include sufficient calcium and vitamin D together with a wide spectrum of drug therapies (with antiresorptive, anabolic, or mixed effects). Emerging therapeutic options that target molecules of bone metabolism indicate that the next decade should offer even greater promise for further improving our diagnostic and treatment approaches.

Biochemical markers of bone turnover: potential use in the investigation and management of postmenopausal osteoporosis

INTRODUCTION

The aim was to analyse data on the use of biochemical bone turnover markers (BTM) in postmenopausal osteoporosis.

METHODS

We carried out a comparative analysis of the most important papers concerning BTM in postmenopausal osteoporosis that have been published recently.

RESULTS

The BTM levels are influenced by several factors. They are moderately correlated with BMD and subsequent bone loss. Increased levels of bone resorption markers are associated with a higher risk of fracture. Changes in the BTM during the anti-osteoporotic treatment (including combination therapy) reflect the mechanisms of action of the drugs and help to establish their effective doses. Changes in the BTM during the anti-resorptive treatment are correlated with their anti-fracture efficacy.

CONCLUSION

Biological samples should be obtained in a standardised way. BTM cannot be used for prediction of the accelerated bone loss at the level of the individual. BTM help to detect postmenopausal women who are at high risk of fracture; however, adequate practical guidelines are lacking. BTM measurements taken during the anti-resorptive therapy help to identify non-compliers. They may improve adherence to the anti-resorptive therapy and the fall in the BTM levels that exceeds the predefined threshold improves patients' persistence with the treatment. There are no guidelines concerning the use of BTM in monitoring anti-osteoporotic therapy in postmenopausal women.

Clinical challenges in the management of osteoporosis

While knowledge regarding the diagnosis and treatment of osteoporosis has expanded dramatically over the last few years, gaps in knowledge still exist with guidance lacking on the appropriate management of several common clinical scenarios. This article uses fictional clinical scenarios to help answer three challenging questions commonly encountered in clinical practice. The first clinical challenge is when to initiate drug therapy in a patient with low bone density. It is estimated that 34 million America have low bone density and are at a higher risk for low trauma fractures. Limitations of using bone mineral density alone for drug therapy decisions, absolute risk assessment and evidence for the cost-effectiveness of therapy in this population are presented. The second clinical challenge is the prevention and treatment of vitamin D deficiency. Appropriate definitions for vitamin D insufficiency and deficiency, the populations at risk for low vitamin, potential consequences of low vitamin D, and how to manage a patient with low vitamin D are reviewed. The third clinical challenge is how to manage a patient receiving drug therapy for osteoporosis who has been deemed a potential treatment failure. How to define treatment failure, common causes of treatment failure, and the approach to the management of a patient who is not responding to appropriate osteoporosis therapy are discussed.

Cancer treatment-related bone loss: a review and synthesis of the literature

Cancer therapy can result in significant bone loss and increased risk of fragility fracture. Chemotherapy, aromatase inhibitors, and gonadotropin-releasing hormone analogues contribute to increases in the rate of bone remodelling and reduce bone mineral density. Patients with prostate cancer on androgen deprivation therapy experience an increase in the risk of fracture. New research has demonstrated the key role played by bisphosphonates in preventing declines in bone density and increases in bone remodelling. Novel antiresorptive agents targeting receptor activator of nuclear factor κB ligand have great potential in skeletal protection and prevention of bone loss related to cancer therapy. Early assessment of skeletal health, followed by initiation of calcium, vitamin D, and an exercise program are valuable in the prevention and treatment of osteoporosis. In addition, individuals at increased risk for fracture should be offered antiresorptive therapy. Early data have demonstrated that bisphosphonates are able to prevent the bone loss and increased bone remodelling associated with cancer therapy, including aromatase inhibition and androgen deprivation therapy. The present paper reviews the new research and advances in the management of bone loss associated with both cancer therapy and estrogen deficiency in the postmenopausal female.

Optimising antiresorptive therapies in postmenopausal women: why do we need to give due consideration to the degree of suppression?

Accelerated bone turnover with bone resorption exceeding bone formation is a major mechanism underlying postmenopausal bone loss and hence the development of osteoporosis. Accordingly, inhibition of bone resorption is a rational approach for the prevention of osteoporosis. In this context, the most logical option, hormone replacement therapy, reverses the rate of bone turnover to premenopausal levels, whereas the magnitude of inhibition by amino-bisphosphonates and the recently introduced anti-receptor activator of NFkappaB ligand (RANKL) antibody often exceeds this. As bone turnover has crucial implications for the continuous renewal of bone tissue, the over-suppression of bone turnover has potential consequences for bone quality and strength. Long-term treatment with potent bisphosphonates has recently been associated with osteonecrosis of the jaw and dose-dependent increases in micro-crack accumulation in animals. Although these observations are the subject of ongoing discussions, it is timely to discuss whether the over-suppression of bone turnover below premenopausal levels is really our ultimate goal when defining the success criteria for antiresorptive agents. In this review, the implications of high and excessively low bone turnover of endogenous origin for bone quality, fracture risk and integrity of the jaw are discussed. In addition, animal and clinical research revealing initial findings regarding the potential adverse effects of drug-induced suppression of bone remodeling are summarised. The inhibition of bone resorption, which is either transient between doses (e.g. with calcitonin) or does not exceed premenopausal levels (with hormone replacement therapy or selective estrogen receptor modulators), is preferable because it not only provides similar antifracture efficacy but can also assist in the maintenance of the dynamic repair of micro-cracks/micro-fractures.

Alendronate sodium in the management of osteoporosis

Alendronate is one of the best and most extensively studied bisphosphonates in the treatment of osteoporosis. This review considers in detail the major pivotal study, the fracture intervention trial (FIT), upon which the use of alendronate is based and which was a landmark study in terms of design, size and clinical impact. The role of alendronate has subsequently been underscored by a range of studies extending the clinical indications for its use and consolidating the effect on reducing both vertebral and non-vertebral fracture risk. Although the emphasis of these studies has predominantly been on the management of postmenopausal osteoporosis, data is also available in primary prevention, men, and glucocorticoids-induced osteoporosis. Direct comparison between the different drugs used to treat osteoporosis with fracture end points are needed for patients and doctors to make informed choices, but the size of such studies are prohibitive. Clinical trials using surrogate markers such as bone mineral density and biochemical markers of bone turnover have been performed which provide some helpful information but the limitations of this approach need to be recognized.

Alendronate for osteoporosis in men with androgen-repleted hypogonadism

Male hypogonadism is associated with low bone mineral density (BMD) and an increased risk of fractures. Testosterone replacement therapy improves BMD in young hypogonadal men. This effect is milder in older patients, who are at greater risk for fractures. We studied the effects of alendronate or placebo on BMD in 22 osteoporotic men, 29-69 years of age (mean, 50.2+/-11.2 years) with long-standing hypogonadism, receiving standard testosterone replacement treatment. Alendronate 10 mg daily (n=11) increased lumbar-spine BMD by 6.0 and 8.4% at 6 and 12 months, respectively, compared with -0.5% at 6 months and +3.3% at 12 months in the placebo group (n=11; P<0.005). Alendronate also increased mean femoral-neck BMD by 1.9% after 1 year, compared to a 1.4% decrease with placebo (P<0.005), and increased the total body bone mineral content by 4.4%, compared to a 0.6% decrease with placebo (P=0.07). After 6 months alendronate suppressed urinary deoxypyridinoline by 50% (P<0.005), compared to a 24% decrease in the placebo group. Both the alendronate and placebo groups continued with alendronate 70 mg once weekly for the following 2 years. Lumbar-spine BMD during this open-label study phase did not change significantly in the group originally treated with alendronate, but continued to increase in the placebo-alendronate group by 5.4, 6.5, and 6.2% after 18 (6 months of alendronate), 24 and 36 months, respectively (P<0.05). Femoral-neck BMD continued to increase in both groups receiving active therapy; in the alendronate-alendronate group by 3.7, 2.7, and 5.2% after 18, 24, and 36 months, respectively (P=0.01), and in the placebo-alendronate group by 0.7 and 1.9% at 24 (first 12 months of alendronate) and 36 months, respectively (P<0.05). Our results support the long-term administration of alendronate along with testosterone replacement to men with hypogonadism-induced osteoporosis.

Incidence and causes for failure of treatment of women with proven osteoporosis

The purpose of this study was to examine factors influencing women's compliance with medical therapy for osteoporosis in Israel. The study population consisted of women diagnosed with osteoporosis using a DEXA examination in the year 2000. Medication purchases for a period of 13 months after the exam were analyzed. Data were gathered from the computerized data base of Clalit Health Care Services and phone interviews. Treatment was divided into specific drugs and food additives (preparation of calcium plus vitamin D). Full, intermediate, low and no compliance were defined as >80, 50-80, 25-50 and <25% of treatment days, respectively. In the study, 857 women with a mean age of 73.6 years were enrolled; 581 (67.8%) were interviewed by telephone. Most of women were undereducated and unemployed. Twenty percent did not purchase any specific drug; 4.5% did not purchase any drug or food additive for osteoporosis; 60% were fully or intermittently compliant (by purchasing) with drug therapy. The most frequent single specific drugs purchased were bisphosphanates and SERM: 62.3 and 76.3% purchased bisphosphanates and/or food additives, respectively. Multi-variant analysis showed that predictors of compliance were healthy women, compliant with calcium plus vitamin D preparations, and/or spending more on drugs. Reasons for low or non-compliance were inconsistent recommendations by various physicians and the side effects of specific drugs. The relatively high compliance rate of osteoporosis treatment may be attributed to the increase in awareness of its benefits. The effect of physicians on compliance needs further investigation.

BsmI vitamin D receptor genotypes influence the efficacy of antiresorptive treatments in postmenopausal osteoporotic women. A 1-year multicenter, randomized and controlled trial

Vitamin D receptor (VDR) gene polymorphisms could be considered one of the factors influencing the efficacy of the anti-osteoporotic treatments. In this multicenter, prospective, randomized and controlled trial we evaluated whether BsmI vitamin D receptor (VDR) genotypes influence the efficacy of antiresorptive treatment regimes (administered alone or in combination) in postmenopausal osteoporotic women. Using restriction endonuclease, we identified the BsmI VDR polymorphism in 1,100 postmenopausal women with osteoporosis. The women were randomized, taking account of genotype, into five treatment groups: (1) alendronate (Aln, 10 mg/day) plus raloxifene (Rlx, 60 mg/day); (2) Aln plus hormone replacement therapy (HRT, 0.625 mg/day conjugated equine estrogens plus 2.5 mg/day medroxyprogesterone acetate); (3) Aln alone; (4) HRT alone; and (5) Rlx alone. Lumbar-spine bone mineral density (BMD) and bone turnover markers were measured at study entry and after 1 year of treatment. Using the general linear model (GLM) repeated-measures procedure, the means of BMD and bone turnover markers significantly differed from baseline after a period of treatment. In particular, the mean change from baseline for BMD was -0.034 (95% confidence interval [CI]: -0.037 to -0.031, P <0.001); for serum osteocalcin (OC) it was 1.369 (95% CI: 1.289 to 1.448, P <0.001); and for urinary deoxypyridinoline (DPD) it was 1.322 (95% CI: 1.242 to 1.401, P <0.001), indicating a considerable variation before and after treatment of these indicators. In all three cases these effects appeared significantly influenced by treatments, genotypes, and the treatments*genotypes interaction term (P <0.001 each, except for the BMD and genotype effect with P =0.02), and not by the investigational centers involved in the study. In conclusion, in postmenopausal osteoporotic women, BsmI VDR genotypes influence the efficacy of antiresorptive drugs particularly when used in combination.

Combination therapy for osteoporosis: considerations and controversy

Combination therapy, the simultaneous use of two pharmaceutical agents with the goal being reduction of fracture risk, is an area of substantial clinical interest. This paper summarizes the rationale, existing clinical trials data, and other considerations relevant to combination therapy for osteoporosis. Combinations of antiresorbers (eg, estrogen plus bisphosphonates) produce greater increases in bone mass than either treatment alone. Conversely, combining anabolic agents (parathyroid hormone) with bisphosphonates does not produce additive effects. None of the existing studies are large enough to determine whether combination treatment reduces fracture risk to a greater extent than use of a single agent. However, it is certain that combination treatment will increase cost and likely that it will increase side effects and reduce therapy adherence. Given the absence of demonstrated fracture reduction benefit, increased cost and likely increase in adverse events, combination therapy is not currently recommended.

An update on bisphosphonates

Over the past 15 years, bisphosphonates have been demonstrated as effective therapy for the treatment of osteoporosis based on their ability to suppress bone turnover resulting in increased bone mineral content and increased bone strength. The mechanism of action at the cellular level has been identified, and the more potent nitrogen-containing bisphosphonates clearly have reduced the risk of vertebral and nonvertebral fractures in patients with osteoporosis. Future use of these therapies is evolving to less frequent administration, and the interaction with anabolic therapies is presently being defined. Data to date support long-term safety with bisphosphonates in small numbers of patients treated for 5 to 10 years, and continued vigilant follow-up of the post-marketing experience will be necessary to determine if sustained bone turnover suppression is associated with rare musculoskeletal adverse events. Further development of bisphosphonates as adjunctive therapy to reduce bone metastases is in progress, and trials evaluating bisphosphonates as a structure modifying agent in osteoarthritis are nearing completion.

Monitoring hormone replacement therapy by biochemical markers of bone metabolism in menopausal women

Biochemical markers of bone metabolism are divided into two groups: formation and resorption markers. Bone turnover is a dynamic process, which increases in postmenopausal period. Hormone replacement therapy (HRT) can diminish this increased bone turnover. Biochemical markers reflect acute changes in bone metabolism. Therefore, they may be very useful for the prediction of subsequent bone mineral density changes after HRT in menopausal women. Both oral and transdermal routes of HRT are efficacious in decreasing the levels of biochemical markers. However, markers do not replace bone mineral density measurement. Collagen type I cross linked N-telopeptide, collagen type I cross linked C-telopeptide, and osteocalcin are the most promising markers.