Treatment of postmenopausal osteoporosis

Bone mineral density (BMD) assessment of central skeletal sites from peripheral BMD and ultrasonographic measurements: an improved solution employing age and weight in type 3 regression

The objective of this study was to develop a method whereby bone mineral density measurements of the heel and finger, as well as ultrasonographic measurements of calcaneal sound transmission, could identify individuals with a diagnosis of osteoporosis or osteopenia by the World Health Organization criteria for these diagnoses in the central skeleton (i.e., the lumbar spine (LS) and hip [femoral neck] [FN]). Two hundred and forty-four women in a university hospital laboratory setting had dual-energy X-ray absorptiometry measurements of bone mineral density (BMD) in the calcaneus, finger, hip, and spine, and quantitative ultrasound of the calcaneus. Regression equations were developed to predict central bone mineral T-scores from T-scores of peripheral measurements, adjusted by age and weight. Equations were validated by predicting the cut point for osteopenia at the lumbar spine and hip (T-score=-1.0). Ninety-five percent confidence intervals of the mean predicted LS or FN T-score from each peripheral site included -1.0. We conclude that our derived regression equations (taking into account interaction of peripheral BMD with patient age and weight) are useful for predicting T-scores in the central skeleton. This approach reduces the potential for misdiagnosis, which can result if one uses unadjusted peripheral T-scores, which are only moderately correlated with the central measurements of BMD.

The DXL Calscan heel densitometer: evaluation and diagnostic thresholds

The DXL Calscan (Demetech AB) is a new dual energy X-ray absorptiometry device for determining heel bone mineral density (BMD). The system is based on the standard technique of dual energy X-ray absorptiometry (DXA), using a fan beam configuration, but introduces an additional laser measurement of heel thickness intended to improve accuracy. We have examined the utility, in vitro and in vivo performance of the DXL Calscan and established triage thresholds based on the UK's National Osteoporosis Society guidelines on peripheral densitometry. The Calscan proved convenient, easy to use and was stable over time and within a range of operating temperatures. Short-term in vitro precision as %CV, with phantom repositioning, was 0.75% and long term precision 0.73%. Precision in vivo, determined from duplicate right heel scans of 67 subjects, was 1.19%. Effective radiation dose to the patient was <0.1 microSv per scan. 140 white females (70 osteoporotic and 70 non-osteoporotic), aged 55-70 years underwent scans of both heels. Subjects were defined as osteoporotic or non-osteoporotic on the basis of axial DXA (spine L2-L4 and total hip). Triage thresholds for reassurance-referral or referral-treatment were 0.391 g cm(-2) and 0.306 g cm(-2) for non-dominant and 0.395 g cm(-2), 0.294 g cm(-2) for dominant heel, respectively. The non-dominant heel proved slightly superior to the dominant for triage purposes. Of the seven non-osteoporotic subjects misclassified as osteoporotic by Calscan of either heel, six had severe axial osteopenia. If operated by trained personnel and used in appropriate populations exhibiting risk factors, the Calscan is well suited for use in the management of post-menopausal osteoporosis.

Effects of alendronate combined with hormone replacement therapy on osteoporotic postmenopausal Chinese women

To evaluate the effect of alendronate combined with hormone replacement therapy (HRT) on postmenopausal osteoporotic Chinese women living in Taiwan, we treated 151 women (age range, 47-70 years; mean, 61 years) with conjugated equine estrogen (0.625 mg), medroxyprogesterone 5 mg, and elemental calcium 500 mg daily with either alendronate 10 mg (n = 79) or placebo (n = 72), and measured their bone mineral density (BMD) at the lumbar spine and hip every 6 months for 3 years. Urine N-telopeptide of type I collagen corrected by concentration of urine creatinine (NTx/Cr) and serum osteocalcin (OC) concentration was also measured at weeks 2, 4, and every 3 months from month 3 for 2 years. Significantly higher percentage increases in BMD at the lumbar spine (P < .0001, 2-way analysis of variance) throughout the 36-month treatment period were found in the alendronate plus HRT group than in the HRT-only group. However, there was no difference in BMD at the femoral neck and trochanter between these 2 groups. Treatment with alendronate plus HRT resulted in a 10.1% increase at the L-spine BMD and a 7.7% increase at the trochanter BMD at the end of the 3-year study period (P < .01, compared with baseline at both sites). A significant decline in urine NTx/Cr was observed at week 4 in the alendronate plus HRT group, whereas in the HRT-only group, a significant decline in urine NTx/Cr occurred at month 9. By the end of 24 months, urine NTx/Cr decreased by 49.7% in the alendronate plus HRT group (P = .001 compared with a 20.4% increase in the HRT group). A significant decline in serum OC level occurred at month 3 in the alendronate plus HRT group, whereas a similar decline was observed at month 6 in the HRT-only group. By the end of 24 months, serum OC decreased by 52.2% in the alendronate plus HRT group (P < .001 compared with a 1.5% increase in the HRT-only group). Subjects treated with alendronate plus HRT had a significantly greater percentage decrease in urine NTx/Cr (P = .0001) and serum OC (P = .0007) than subjects treated with HRT only throughout the 24-month treatment period by 2-way analysis of variance comparison. There was no difference in upper gastrointestinal or drug-related side effects between groups. In conclusion, our data suggest that the use of alendronate combined with HRT for 3 years was well tolerated and it significantly increased BMD at the L-spine and hip in postmenopausal Chinese women with osteoporosis. This regimen is safe and can be used in subjects who have no satisfactory response to a single agent or who have very low BMD with multiple risks. However, this study does not indicate whether HRT plus alendronate has any greater effect on BMD than alendronate alone.

Assessment of compliance with osteoporosis treatment and its consequences in a managed care population

OBJECTIVE

To evaluate non-compliance with osteoporosis medications as well as its implications for health and economic outcomes in actual practice.

STUDY DESIGN

Data on demographics, prescription drug dispensing, physician services and hospitalizations were obtained from a US managed care database for women with osteoporosis who were dispensed an osteoporosis medication between 1997 and 2002.

METHODS

Each subject's pattern of osteoporosis medication use was reconstructed using dispensing records. Subjects were considered compliant over a given period if their medication possession ratio (MPR) was >or=80% and gradients of compliance (<50% poor, 50-80% medium, 80-90% good, >90% excellent) were also examined. Using proportional hazards, the association between compliance over time and fracture rates was examined; Poisson regression was used for hospitalization and log-linear regression for medical costs.

RESULTS

38,120 women with osteoporosis were identified with a mean age of 66 years and an average follow-up of 1.7 years. Three quarters of them had an MPR below 80% when their entire follow-up was considered. Low compliance was associated with a 17% (95% CI 9-25%) increase in the fracture rate, adjusting for other known risk factors. Controlling for the specific drug regimen did not alter the association. Low compliance was also associated with a 37% (95% CI 32-43%) increase in the risk of all-cause hospitalization; and average monthly costs for all medical services combined were higher: 600 US dollars vs. 340 US dollars (P < 0.0001). Similar associations were observed when using the gradients of compliance.

CONCLUSIONS

The desired goal of keeping patients with osteoporosis on chronic treatment is not being achieved adequately in actual practice and the potential social and economic implications of this behavior are substantial. Until compliance is improved, society will continue to fail in meeting an important public health goal.

Therapy Insight: osteoporosis during hormone therapy for prostate cancer

The intended therapeutic effect of gonadotropin-releasing-hormone (GnRH) agonists is hypogonadism, which is a leading cause of osteoporosis in men. Observations are consistent with this effect: GnRH agonists decrease bone mineral density and increase fracture risk in men with prostate cancer. Estrogens play a central role in homeostasis of the normal male skeleton and evidence suggests that estrogen deficiency is primarily responsible for the adverse skeletal effects of GnRH agonists. The mechanism of treatment-related bone loss involves acceleration of physiologic bone turnover. In small, randomized, controlled trials, bisphosphonates (pamidronate, zoledronic acid) and selective estrogen-receptor modulators (raloxifene, toremifene) increased bone mineral density in GnRH-agonist-treated men. Two ongoing large, randomized, placebo-controlled studies will prospectively define fracture outcomes in men with prostate cancer and assess the efficacy of novel pharmacologic interventions (AMG 162, toremifene) in GnRH-agonist-treated men.

Strontium ranelate: an increased bone quality leading to vertebral antifracture efficacy at all stages

Strontium ranelate is a new antiosteoporotic treatment with a dual mode of action, both increasing bone formation and decreasing bone resorption, which rebalances bone turnover in favor of bone formation and increases bone strength. The antifracture efficacy of strontium ranelate, 2 g per day orally, in the treatment of postmenopausal osteoporosis has been investigated in a large-scale, international, multicenter, phase 3 program in which more than 7000 patients were recruited. This article deals with the vertebral antifracture efficacy of strontium ranelate in postmenopausal women with osteoporosis. A significant early (after 1 year) and sustained (over 3 years) antifracture efficacy of strontium ranelate, compared with placebo, was demonstrated in patients with prevalent vertebral fracture with reductions in risk of new vertebral fracture of 49% after 1 year (P < 0.001) and 41% over 3 years (P < 0.001). In addition, the relative risk of clinical vertebral fracture was significantly reduced by 52% (P = 0.003) after 1 year and by 38% (P < 0.001) over 3 years in the strontium ranelate group compared with placebo. Strontium ranelate was also demonstrated to significantly decrease the relative risk of vertebral fractures by 45% (P < 0.001) in patients without prevalent vertebral fracture over 3 years, vs. placebo. Bone mineral density was linearly increased during 3 years of treatment with strontium ranelate in comparison with placebo. Strontium ranelate was well tolerated throughout the entire duration of the clinical trials. Thus, strontium ranelate, 2 g per day orally, is a new, effective, and safe treatment for postmenopausal patients with osteoporosis, to reduce the vertebral fracture risk in patients with or without a history of vertebral fracture.

Strontium ranelate: the first dual acting treatment for postmenopausal osteoporosis

Currently available medications, such as bisphosphonates, selective estrogen receptor modulators, and teriparatides, have shown their ability to reduce vertebral and/or nonvertebral fractures. Questions remain regarding their long-term innocuousness and several studies showed that adhering to currently marketed anti-osteoporotic medications remain sub-optimal. There is, therefore, an urgent need for the development of new effective, safe, and user-friendly medications to optimize the treatment of postmenopausal osteoporosis. The current review was designed to assess, through an extensive literature search, the antifracture efficacy of strontium ranelate on the axial and appendicular skeleton. Two multinational Phase 3 clinical trials have shown its efficacy and safety in the treatment of postmenopausal osteoporosis. In the Spinal Osteoporosis Therapeutic Intervention trial, strontium ranelate (2 g/day) treatment reduced the relative risk of a new vertebral fracture by 41% after 3 years compared with placebo. Data from the Treatment of Peripheral Osteoporosis study showed a 16% reduction in the relative risk of nonvertebral fracture in all patients and a 36% reduction in hip fracture in high-risk patients. Strontium rane-late reduces the risk of all fragility fractures and is well tolerated, which makes it a new first-line alternative in the treatment of postmenopausal osteoporosis.

LEVEL OF EVIDENCE

Therapeutic study, Level II (lesser quality randomized controlled trial [eg, < 80% followup, no blinding, or improper randomization]). See the Guidelines for Authors for a complete description of the levels of evidence.

Protelos: nonvertebral and hip antifracture efficacy in postmenopausal osteoporosis

Strontium ranelate is a new treatment for postmenopausal osteoporosis, simultaneously increasing bone formation and decreasing bone resorption, thus rebalancing bone turnover in favor of bone formation. Strontium ranelate was demonstrated to significantly reduce the relative risk of vertebral fracture whatever the severity of the disease. In the TReatment Of Peripheral OSteoporosis (TROPOS) study, the incidence of nonvertebral and hip fractures, following treatment with strontium ranelate (Protelos, Servier) at a dosage of 2 g/day orally, was assessed over a 3-year period. In this double-blind, placebo-controlled trial, 5091 women with postmenopausal osteoporosis were assigned to either strontium ranelate (n = 2479) or placebo (n = 2453) treatment. Overall, the reduction in risk for nonvertebral fractures in patients treated with strontium ranelate was 16% (P = 0.04) and for major fractures (hip, wrist, pelvis and sacrum, ribs and sternum, clavicle and humerus), it was 19% (P = 0.031), compared with those treated with placebo. Women with osteoporosis and aged 74 years or more who were treated with strontium ranelate (n = 982) had a 36% reduction in risk of hip fracture (P = 0.046) over 3 years compared with those treated with placebo (n = 995). The difference in bone mineral density between groups was 8.2% for femoral neck and 9.8% for total hip at 3 years. The incidence of adverse events was comparable between groups. The study demonstrates that strontium ranelate treatment offers a safe and effective means of reducing the risk of nonvertebral and hip fractures in postmenopausal women with osteoporosis.

Effect of calcium tablets on interpretation of lumbar spine DXA scans

Undissolved calcium (Ca) tablets in the gastrointestinal tract at the time of a dual-energy X-ray absorptiometry (DXA) scan could conceivably affect the accuracy of the lumbar spine bone mineral density (BMD) determination. We studied phantoms and volunteers to determine the effect of Ca tablets overlying bone, Ca tablets in the soft-tissue field, and Ca tablets overlapping both bone and soft tissue. For L1-4, a 500-mg Ca tablet taped to the phantom surface or the skin of volunteers resulted in <or=2.2% mean increase in measured BMD (less than the lumbar spine least significant change), changing the T-score for L1-4 very little. However, an overlying Ca tablet had a substantial effect on BMD of a single vertebral body. Greater effects were seen with higher amounts of tablet Ca and with lower BMD, resulting in as much as a 12.6% mean increase in single vertebral BMD in the in vivo series. Recent versions of DXA software successfully identified tablets in the soft-tissue field as artifact and eliminated the tablet pixels from the analysis. However, tablets overlapping bone and soft tissue necessitated operator intervention to either exclude the affected vertebral body or adjust edges by mapping the tablet as artifact and/or neutral field. A paraffin-coated Ca tablet swallowed by a volunteer was tracked serially by DXA during gastrointestinal transit. Similar effects were seen as with the phantom and volunteer studies using external tablets; there was little effect of the Ca tablet on L1-4 BMD either with the tablet overlying bone or in the soft-tissue field. We conclude that undissolved Ca tablets introduce small artifacts on L1-L4 BMD insufficient to alter diagnostic categorization of patients. However, if only two or three vertebral levels are available, misclassification of the patients may occur due to tablet artifact. The precision of monitoring BMD over time could also be adversely affected by tablet artifact if a tablet was directly overlying bone and undetected, especially with smaller regions of interest and with lower baseline BMD.

ALDH2 polymorphisms and bone mineral density in an elderly Japanese population

INTRODUCTION

Osteoporosis is a multifactorial genetic disease which greatly increases the risk of bone fracture in elderly persons.

METHODS

Four hundred and three recipients of a community health screening program were examined for the presence/absence of osteoporosis and 11 kinds of gene polymorphisms as a means of determining the relation between these gene polymorphisms and osteoporosis. The gene polymorphisms screened were: alcohol sensitivity-associated polymorphisms of alcohol dehydrogenase (ADH2) Arg47His, aldehyde dehydrogenase (ALDH2) Glu487Lys, smoking sensitivity-associated polymorphisms of glutathione S transferase (GST) M1, (GST)T1, NAD(P)H quinone oxidoreductase 1 (NQO1) C609T, inflammation-associated polymorphisms of interleukin-1beta (IL-1B)T-31C, tumor necrosis factor alpha (TNF-alpha) T-1031C, endothelial constitutive nitric oxide synthase (ecNOS) Glu298Asp, longevity-associated polymorphism of mitochondrial DNA (mtDNA) 5178 A/C, allergy-associated polymorphism of interleukin-4 (IL-4), and immunity-associated polymorphism of CD14.

RESULTS

A significant association was found between the ALDH2Glu478Lys gene polymorphisms and osteoporosis. In the osteoporosis group of patients, a significant difference was noted between the Lys/Lys group and the group comprising Glu/Lys and Glu/Glu groups (namely, the genotypes including Glu alleles). In the Lys/Lys group, after age, sex, BMI, smoking history and alcohol consumption history had been adjusted for, the morbidity rate was significantly elevated [odds ratio (OR): 3.33; 95% confidence interval (95% CI): 1.28-8.71; p=0.014], and the effect was even more evident in the sub-group of women with osteoporosis (OR: 4.31; 95% CI: 1.24-14.92; p=0.021).

CONCLUSIONS

The present results suggest that active prophylactic interventions such as dietary, exercise, and pharmacological therapies should be offered to non-carriers of the Glu allele (Lys/Lys).

Two-year clinical trial of oral alendronate versus intravenous pamidronate in children with osteogenesis imperfecta

A 2-year prospective, partially randomized open-label trial comparing oral alendronate with intravenous pamidronate therapy in children with OI showed equivalence in increasing total body BMD, spine BMD, and linear growth, and decreasing bone turnover and fracture incidence. Children with mild OI had greater responses than severe OI in BMD and growth.

INTRODUCTION

Bisphosphonate therapies increase BMD and may reduce fractures in children with osteogenesis imperfecta (OI). A study directly comparing oral with intravenous bisphosphonate has not been published. This clinical trial compares oral alendronate with intravenous pamidronate in children with OI using an open-label, prospective, 2-year, randomized design.

MATERIALS AND METHODS

Children over the age of 3 years were stratified by bone age, pubertal stage, and type of OI and then randomized to receive oral alendronate 1 mg/kg/day in tablet form or intravenous pamidronate, 3 mg/kg/4 months. One child was assigned to pamidronate. One child randomized to intravenous pamidronate changed to oral alendronate. Eighteen children completed 12 months of therapy: nine on oral alendronate and nine on intravenous pamidronate. Primary outcome efficacy was increase in BMD. Secondary outcomes included changes in bone turnover biomarkers, fracture incidence, and growth.

RESULTS

Total body and lumbar spine BMD increased, turnover markers decreased, and linear growth increased equivalently with oral and intravenous therapy. Fracture incidence showed a trend to decrease in both groups, with a significant decrease in fracture rates when the oral and intravenous groups were pooled. There were greater responses in BMD and growth in children with milder OI (type I) than those with more severe disease (types III and IV), but there were no significant effects of age or pubertal stage.

CONCLUSIONS

Oral and intravenous bisphosphonate therapies are equally effective in children with OI and are particularly effective in milder forms. The oral route is highly acceptable in children and has practical advantages over the intravenous route.

Predicting the risk of fracture at any site in the skeleton: are all bone mineral density measurement sites equally effective?

The ability to assess a patient's risk of fracture is fundamental to the clinical role of bone densitometry. Fracture discrimination is quantified by the relative risk (RR), defined as the increased risk of fracture for a 1 standard deviation decrease in bone mineral density (BMD). The larger the value of RR, the more effective measurements are at identifying patients at risk of fracture. Epidemiological studies show that RR values for predicting the risk of any fracture are approximately the same for all BMD measurement sites. In this study, we show theoretically that this interesting observation is predictable and a consequence of two related observations: (1) that fracture prediction by BMD measurement sites distant from the fracture site is quantitatively explained by the correlation of BMD measurements and (2) that all correlation coefficients between distant BMD sites are comparable, with values in the range r = 0.55-0.65. The first of these conditions (referred to as the correlation hypothesis) is important because it sets a lower limit on the RR values at distant BMD sites on the assumption that measurements at these sites contain no independent information about fracture risk over and above that provided by their correlation with the fracture site BMD. If the correlation hypothesis is true, the present study points to the importance of the correlation coefficient between BMD sites as a key index that is indicative of the ability of different types of measurement to predict fracture risk. If, on the contrary, the correlation hypothesis is not valid, there is scope to improve bone densitometry by further studies to better identify those measurements that do provide independent information about fracture risk and how best to integrate this information with existing techniques to improve decision making.

A list of device-specific thresholds for the clinical interpretation of peripheral x-ray absorptiometry examinations

The UK National Osteoporosis Society (NOS) has recently issued new guidelines on the use of peripheral x-ray absorptiometry (pDXA) devices in managing osteoporosis. The NOS guidelines recommend a triage approach in which patients' bone mineral density (BMD) measurements are interpreted using upper and lower thresholds specific to each type of pDXA device. The thresholds are defined so that patients with osteoporosis at the hip or spine are identified with 90% sensitivity and 90% specificity. Patients with a pDXA result below the lower threshold are likely to have osteoporosis at the hip or spine, patients with a result above the upper threshold are unlikely to have osteoporosis, while those between the two thresholds require a hip and spine BMD examination for a definitive diagnosis. This report presents data from a multicenter study to establish the triage thresholds for a range of pDXA devices in use in the UK. The subjects were white female patients aged 55-70 years who met the normal referral criteria for a BMD examination. For each device, at least 70 women with osteoporosis at the hip or spine and 70 women without osteoporosis were enrolled. All women had hip and spine BMD measurements using axial DXA systems that were interpreted using the National Health and Nutrition Examination Survey (NHANES) reference range for the hip and the manufacturers' reference ranges for the spine. Data are presented for five different devices: the Osteometer DTX-200 (forearm BMD), the Schick AccuDEXA (hand BMD), the GE Lunar PIXI (heel BMD), the Alara MetriScan (hand BMD), and the Demetech Calscan (heel BMD). The clinical measurements were supplemented by theoretical modeling to estimate the age dependence of the triage thresholds and the effect of the correlation coefficient between pDXA and axial BMD on the percentage of women referred for an axial BMD examination. In summary, this study provides thresholds for implementing the new NOS guidelines for managing osteoporosis using pDXA devices. The figures reported apply to postmenopausal white women aged 55-70 years who meet the conventional criteria for a BMD examination. The results confirm that the thresholds are specific to each type of pDXA device and that the NOS triage algorithm requires 40% of women to have an axial DXA examination.

Management of Bone Health in Postmenopausal Women

Osteoporosis is a major public health problem. We now have an approach to case finding that involves the measurement of bone mineral density in people at high risk of fractures. The management of the individual includes the identification of risk factors, the choice of optimal therapy and the encouragement of long-term adherence with the planned treatment. The drugs that are available for the prevention of fractures are classed as anticatabolic or anabolic. The efficacy of these agents can be evaluated in the individual by monitoring changes in bone mineral density or bone turnover markers.

Bone loss and the aromatase inhibitors

The increasing use of systemic adjuvant therapies has considerably improved the prognosis from early breast cancer. However, some of these therapies affect bone metabolism, resulting in osteoporosis. Aromatase inhibitors lower circulating oestrogen levels to almost unrecordable levels in postmenopausal women, predisposing them to bone loss with an increase in fracture risk. Ongoing clinical trials are favouring the use of the aromatase inhibitors over tamoxifen and this may advocate greater use of these drugs in the future. Strategies for the identification and management of treatment-induced bone loss are currently being defined.

Bisphosphonate-associated Scleritis: A Case Report and Review

An 86-year-old female was treated for osteoporosis with alendronate, an aminobisphosphonate. Six weeks after alendronate therapy began, scleritis developed in the patient's right eye. The alendronate was discontinued, and, with the administration of prednisone, the symptoms of scleritis fully resolved. Rechallenge resulted in recurrence of the symptoms. Bisphosphonates are commonly used in the management of osteoporosis and are generally safe agents. Rarely, they have been linked with ocular inflammation. This case report reviews the literature on the ocular effects of bisphosphonates and discusses a possible mechanism for the association.

Assessment of experimental osteoporosis using CT-scanning, quantitative X-ray analysis and impact test in calcium deficient ovariectomized rats

INTRODUCTION

Osteoporosis is a major health problem in the elderly population particularly in postmenopausal women. Various techniques are currently available for detection and diagnosis of osteoporosis in humans, but not all of these can be used for evaluation of osteoporosis in animals. We assessed the feasibility and applicability of a spiral CT-scanning technique for use in evaluating bone loss in rats. In addition, we also tested the applicability of dispersive quantitative X-ray analysis (QXRA) coupled with scanning electron microscopy (SEM), and impact test to detect bone mineral content and biomechanical strength, respectively.

METHODS

Twenty female Sprague Dawley rats were randomly assigned to sham operated or bilaterally ovariectomized groups and fed with a calcium-deficient diet for 16 weeks. Femurs and tibias were collected at termination. Using a spiral CT-scanner various cortical bone morphometric indices were measured in femurs. SEM-QXRA was used to quantify the calcium to phosphorus ratio (Ca:P) in regions of high bone turnover both in sham and CD-OVX rats. Tibias were subjected to the impact test for evaluation of biomechanical strength.

RESULTS

Compared to sham operated rats, the CD-OVX animals had decreased combined cortical thickness (CCT), cortical area (CA), cortical area/periosteal area and radial density (RD), with increased medullary width and cross sectional areas as determined by CT-Scanning technique. SEM-QXR analysis indicates a decreased Ca:P ratio in the metaphyseal regions of distal femurs in CD-OVX rats when compared to sham-operated rats. The results of the impact test demonstrate lower threshold energy in tibias of CD-OVX rats compared to sham operated rats.

DISCUSSION

The ability of these techniques to distinguish the bone characteristics of sham-operated rats from CD-OVX rats provides a methodological opportunity to assess osteoporosis in small animals like rats.

Treatment of osteoporotic ovariectomized rats with 24,25(OH)2D3

BACKGROUND

Antiresorptive therapeutic regimens are the mainstay of current management of osteoporosis. Treatments that are promoting new bone formation are less available and less affordable. Previous studies have suggested that 24,25(OH)(2)D(3) could enhance bone formation. The effect of 24,25(OH)(2)D(3) on bone formation in ovariectomized osteopenic rats (OVX) was evaluated in this study.

MATERIALS AND METHODS

Mature Sabra rats were divided into two groups: sham-operated and OVX. Three months after surgery the OVX and sham-operated rats were divided into the following subgroups: (1) sham rats injected with vehicle, (2) sham rats injected with 24,25(OH)(2)D(3), (3) OVX rats injected with vehicle, and (4) OVX rats injected with 24,25(OH)(2)D(3). After 2 weeks' treatment, histomorphometry of the right tibiae was performed.

RESULTS

Ovariectomy resulted in a decrease in total bone volume (TBV/TV) and in bone formation (BFR/BS), P < 0.005 and P < 0.05 respectively, when compared with the sham-operated rats. Beside the decrease in TBV and BFR, the OVX rats showed an increase in osteoclastic bone resorption (P < 0.001 vs. sham). Administration of 24,25(OH)(2)D(3) was followed by an increase in all static and dynamic bone-forming parameters. The TBV/BV (P < 0.025), osteoblast surface (Ob.S/BS) (P < 0.001), as well as the BFR/BS (P < 0.005), increased in the OVX-treated group when compared with the OVX-untreated and sham-operated rats. This increment in bone formation was associated with a decrease in bone resorption (P < 0.001 in OVX-treated vs. OVX-untreated rats).

CONCLUSIONS

This study shows that 24,25(OH)(2)D(3) may be of benefit in experimental osteopenia following ovariectomy, both by suppressing osteoclastic hyperactivity and by stimulating bone formation.

Insulin receptor substrate-1 is required for bone anabolic function of parathyroid hormone in mice

Bone anabolic action of PTH has been suggested to be mediated by induction of IGF-I in osteoblasts; however, little is known about the molecular mechanism by which IGF-I leads to bone formation under the PTH stimulation. This study initially confirmed in mouse osteoblast cultures that PTH treatment increased IGF-I mRNA and protein levels and alkaline phosphatase activity, which were accompanied by phosphorylations of IGF-I receptor, insulin receptor substrate (IRS)-1 and IRS-2, essential adaptor molecules for the IGF-I signaling. To learn the involvement of IRS-1 and IRS-2 in the bone anabolic action of PTH in vivo, IRS-1-/- and IRS-2-/- mice and their respective wild-type littermates were given daily injections of PTH (80 mug/kg) or vehicle for 4 wk. In the wild-type mice, the PTH injection increased bone mineral densities of the femur, tibia, and vertebrae by 10-20% without altering the serum IGF-I level. These stimulations were similarly seen in IRS-2-/- mice; however, they were markedly suppressed in IRS-1-/- mice. Although the PTH anabolic effects were stronger on trabecular bones than on cortical bones, the stimulations on both bones were blocked in IRS-1-/- mice but not in IRS-2-/- mice. Histomorphometric and biochemical analyses showed an increased bone turnover by PTH, which was also blunted by the IRS-1 deficiency, though not by the IRS-2 deficiency. These results indicate that the PTH bone anabolic action is mediated by the activation of IRS-1, but not IRS-2, as a downstream signaling of IGF-I that acts locally as an autocrine/paracrine factor.

Bones in coeliac disease: diagnosis and treatment

Coeliac disease predisposes to metabolic osteopathy. The entity of bone loss is higher in patients with malabsorption at diagnosis but it is also present in asymptomatic or poorly symptomatic patients, occurring in roughly half of them. Calcium malabsorption and the release of proinflammatory cytokines, activating osteoclasts, represent the main mechanisms responsible for bone derangement. In coeliacs, the presence of an increased fracture risk was recently questioned and its importance on clinical grounds was reconsidered, in view of the fact that gluten-free diet generally improves bone mass and, consequently, reduces fracture risk. However, gluten-free diet rarely normalizes bone mass and the co-administration of mineral active drugs may be useful in a subgroup of coeliacs.

Safety profile of raloxifene as used in general practice in England: results of a prescription-event monitoring study

Raloxifene, a selective estrogen receptor modulator (SERM) licensed for the prevention of non-traumatic vertebral fractures in postmenopausal women at increased risk of osteoporosis, was launched in the UK in August 1998. The aim of the study was to monitor the safety of raloxifene prescribed in the primary care setting in England using prescription-event monitoring (PEM). Patients were identified by means of prescription data supplied by the Prescription Pricing Authority between September 1998 and November 2000. Demographic and clinical event data were collected from questionnaires posted to primary care physicians (GPs) at least 6 months after the date of the first prescription for each patient. Information on medical events, suspected adverse drug reactions (ADRs), reasons for stopping treatment, pregnancies, and causes of death was requested. Event rates [Incidence Densities (IDs): no. first reports /1000 patient-months of treatment] were calculated. Differences between IDs for events reported in month one (ID(1)) and months 2-6 (ID(2-6)) of treatment were examined. The cohort comprised 13,987 patients [median age 62 years (IQR 55,69); 99.8% female]. The major indication was osteoporosis (40.9%, n=5725). Flushing was the event with the highest ID in month 1 (22.8), reported most frequently by GPs as an ADR to raloxifene (67/461 reports) and as the reason for stopping (700/4592 reports). Events associated with starting treatment included flushing, malaise/lassitude, headache/migraine, nausea/vomiting, sweating, cramp, pain abdomen, dizziness, diarrhea, mastalgia and vaginal hemorrhage. Less common events reported during treatment included deep vein thrombosis (n=13), pulmonary embolism (n=13), thrombophlebitis (n=31) and visual disturbance (n=29). In this study, there were 122 (0.9%) confirmed deaths, of which 32 causes of death were unknown. This study shows that raloxifene is generally well tolerated when used in general practice in England. Potential signals of unrecognised ADRs requiring further evaluation included gastrointestinal adverse symptoms and vaginal hemorrhage. There were also a small number of reports of events associated with venous thromboembolism and visual disorders that require further investigation.

Targeted overexpression of G protein-coupled receptor kinase-2 in osteoblasts promotes bone loss

To investigate the role of G protein-coupled receptor kinases (GRKs) in regulating bone formation in vivo, we overexpressed the potent G protein-coupled receptor (GPCR) regulator GRK2 in osteoblasts, using the osteocalcin gene-2 promoter to target expression to osteoblastic cells. Using the parathyroid hormone (PTH) receptor as a model system, we found that overexpression of GRK2 in osteoblasts attenuated PTH-induced cAMP generation by mouse calvaria ex vivo. This decrease in GPCR responsiveness was associated with a reduction in bone mineral density (BMD) in transgenic (TG) mice compared with non-TG littermate controls. The decrease in BMD was most prominent in trabecular-rich lumbar spine and was not observed in cortical bone of the femoral shaft. Quantitative computed tomography indicated that the loss of trabecular bone was due to a decrease in trabecular thickness, with little change in trabecular number. Histomorphometric analyses confirmed the decrease in trabecular bone volume and demonstrated reduced bone remodeling, as evidenced by a decrease in osteoblast numbers and osteoblast-mediated bone formation. Osteoclastic activity also appeared to be reduced because urinary excretion of the osteoclastic activity marker deoxypyridinoline was decreased in TG mice compared with control animals. Consistent with reduced coupling of osteoblast-mediated bone formation to osteoclastic bone resorption, mRNA levels of both osteoprotegrin and receptor activator of NF-kappaB ligand were altered in calvaria of TG mice in a pattern that would promote a low rate of bone remodeling. Taken together, these data suggest that enhancing GRK2 activity and consequently reducing GPCR activity in osteoblasts produces a low bone-turnover state that reduces bone mass.

Estrogen therapy in systemic lupus erythematosus

Given the female preponderance of systemic lupus erythematosus (SLE) in humans, the adverse effects of female gender and sex hormones in murine lupus, and numerous reports (retrospective, often anecdotal and uncontrolled) that describe a temporal association between estrogen exposure and development or exacerbation of SLE, it is tempting to accept that estrogens and SLE simply do not mix. While there are valid concerns regarding the use of exogenous estrogens in women with SLE, there are also potential health benefits to be considered. Oral contraceptives (OCs) offer effective birth control and may be bone protective in corticosteroid-treated patients. Recent studies, albeit retrospective, suggest that OCs are well tolerated in patients with SLE. Several salutary effects of postmenopausal estrogens assume particular importance in SLE where the risks of osteoporosis, exaggerated by menopause (natural or cyclophosphamide-induced) and corticosteroids, are substantial. However, the results of the Women's Health Initiative trial significantly limit the use of hormone replacement therapy in the general population, and raise particular concern for SLE patients. Other exogenous hormones (clomifene, gonadotropins, gonadotropin-releasing hormones) may be used to elevate levels of endogenous estrogen and to stimulate ovulation in patients with diminished fertility. Patients with inactive or stable/moderate disease and at low risk for thrombosis may benefit from OCs and other hormonal therapies without a change in lupus activity. Large prospective, double-blind, placebo-controlled studies inclusive of all ethnic groups should provide the basis for more definitive recommendations.

Discordance in diagnosis of osteoporosis using spine and hip bone densitometry

BACKGROUND: Diagnostic discordance for osteoporosis is the observation that the T-score of an individual patient varies from one key measurement site to another, falling into two different diagnostic categories identified by the World Health Organization (WHO) classification system. This study was conducted to evaluate the presence and risk factors for this phenomenon in a large sample of Iranian population. METHODS: Demographic data, anthropometric measurements, and risk factors for osteoporosis were derived from a database on 4229 patients referred to a community-based outpatient osteoporosis testing center from 2000 to 2003. Dual-energy X-ray absorptiometry (DXA) was performed on L1-L4 lumbar spine and total hip for all cases. Minor discordance was defined as present when the difference between two sites was no more than one WHO diagnostic class. Major discordance was present when one site is osteoporotic and the other is normal. Subjects with incomplete data were excluded. RESULTS: In 4188 participants (3848 female, mean age 53.4 +/- 11.8 years), major discordance, minor discordance, and concordance of T-scores were seen in 2.7%, 38.9% and 58.3%, respectively. In multivariate logistic regression analysis, older age, menopause, obesity, and belated menopause were recognized as risk factors and hormone replacement therapy as a protective factor against T-score discordance. CONCLUSION: The high prevalence of T-score discordance may lead to problems in interpretation of the densitometry results for some patients. This phenomenon should be regarded as a real and prevalent finding and physicians should develop a particular strategy approaching to these patients.

L-arginine, the natural precursor of NO, is not effective for preventing bone loss in postmenopausal women

NO is an important regulator of bone turnover. L-Arginine, the natural precursor of NO, can enhance NO production. However, no effect of L-arginine hydrochloride supplementation was found on bone metabolism or on BMD, bone mass, or bone structure of healthy postmenopausal women.

INTRODUCTION

Recent studies indicate that NO exerts an anabolic effect on bone cell activity. The NO level of the human body can be elevated by administering pharmacological NO donors. Animal studies and the first human trial showed that NO donor administration had a positive effect on bone formation and a negative effect on bone resorption. L-arginine, the natural precursor of NO, can enhance NO production. This study was conducted to examine the effect of an oral L-arginine supplement on bone metabolism of healthy postmenopausal women.

MATERIALS AND METHODS

The participants in this study were 30 healthy, age-matched postmenopausal women, divided into two groups. For 6 months, one group (54.5 +/- 4.1 years; 66.3 +/- 10.5 kg) received a daily oral supplement with 18 g L-arginine hydrochloride (14.8 g free L-arginine). The other 15 volunteers (55.3 +/- 4.4 years; 64.2 +/- 9.1 kg) received 18 g dextrose as a placebo. To verify compliance, 24-h urinary excretion of nitrogen was analyzed for 2 consecutive days at baseline and after 2, 4, and 6 months. At baseline and after 2, 4, and 6 months of supplementation, blood was drawn for analysis of insulin-like growth factor-I (IGF-I) and biomarkers of bone metabolism. At baseline, after 6 months, and after 1 year, pQCT measurements were performed at trabecular and cortical sites of the radius and tibia. The two groups of subjects were compared by repeated measures ANOVA.

RESULTS

As expected, in the group with L-arginine hydrochloride supplementation, nitrogen excretion rose, and in the placebo group, it remained constant. Only bone formation marker, procollagen type I propeptides (PICP), increased significantly (p < 0.05) after 6 months of L-arginine supplementation. The results from pQCT showed no significant changes at any site in either group. No significant change in IGF-I concentration, which might have been caused by the L-arginine hydrochloride supplementation, was evident.

CONCLUSIONS

We conclude from these results that supplementation with L-arginine hydrochloride is not effective for improving bone mass in humans.

Risk factors for hip fracture in women with high BMD: EPIDOS study

Hip fractures are common among older women. At the present time, major efforts are being made to identify women with low bone mineral density (BMD). However, more than half of hip fractures occur in women who would not classically be considered osteoporotic by BMD. This study aimed to identify factors associated with hip fracture in women with high BMDs. A total of 7598 French women aged over 74 participated in the EPIDOS study and had BMD measured by dual energy X-ray absorptiometry. Analysis was carried out comparing women with and without hip fractures over more than 3 years of follow-up. The participants were divided into three groups based on femoral neck BMD, so as to have equal numbers in each group (cut-off points=0.601 g/cm(2), and 0.683 g/cm(2)). Multiple risk factors thought to be associated with hip fracture were tested in the high and low BMD groups to search for those whose effect was stronger in the high BMD group. Age adjusted Cox regression was used. Results for continuous variables are reported per standard deviation change. Positive interaction between higher BMD, hip fracture and the following factors were found: age (P<0.01), ultrasound attenuation (P<0.05), urinary deoxypyridinoline (DPD) (P<0.05), left quadriceps strength (P<0.05) and right and left foot coordination (P<0.05). The following factors had a larger hazards ratio in those in the upper third of BMD than the low and were statistically significant: femoral neck BMD, nulliparity, age, ultrasound attenuation and speed, prior fracture, urinary deoxypyridinoline, left grip strength and foot coordination. Multiple factors appear to be more strongly associated with hip fractures in women with high BMD than low. They appear to cluster as factors that may relate to bone turnover and architecture and others which are more subtle measures of left-sided coordination.

Prospective identification of postmenopausal osteoporotic women at high vertebral fracture risk by radiography, bone densitometry, quantitative ultrasound, and laboratory findings: results from the PIOS study

Women with established osteoporosis are at high risk to sustain additional vertebral fractures. Treatment may affect the predictive power of bone densitometry and biochemical techniques. There are few prospective studies comparing fracture prediction by dual-energy X-ray absorptiometry (DXA) and other techniques in treated women with established osteoporosis. The objective of this study was to prospectively assess the predictive power of various DXA and quantitative ultrasound (QUS) techniques for identification of women at high risk to develop new fractures over 1-2 yr. Moreover, we wanted to investigate whether previous or ongoing therapy precluded the use of common clinical laboratory blood tests and bone turnover markers for prediction of fracture risk. We measured prevalent fracture status; bone mineral density (BMD) of the whole body, spine, and hip by DXA; QUS of the calcaneus and the patella; hormones and various markers of bone resorption and formation; and took standard blood tests in 124 women (age 64.9 yr +/- 7.9) with manifest and variously treated postmenopausal osteoporosis. Subsequently, new spine fractures were assessed after 1 yr and, in a subset of 87 women, after 2 yr. Prevalent fractures turned out to be the strongest predictor of subsequent vertebral fractures with an age-adjusted odds ratio (OR) of 3.9 per prevalent fracture over 2 yr. Furthermore, our results underline the predictive power of spinal BMD (sOR = 2.1; standardized OR per 1 standard deviation population variance decrease), whole body BMD (sOR: 2.4), and QUS stiffness index of the calcaneus (sOR: 2.8) for vertebral fracture prediction. QUS of the patella did not predict vertebral fractures. Blood sedimentation rate was predictive in the first year (sOR: 1.9). The predictive power of bone turnover markers, however, appeared to be too low to be detectable in a group of this sample size and it may have been reduced because most women were already receiving treatment. In conclusion, radiographic measures, but not the tested laboratory bone turnover markers, enabled us to identify women (from a population of osteoporotic women who have been treated for some time with a variety of medications) who are at highest risk for developing new vertebral fractures within 1-2 yr.

Osteoporosis and obesity in men receiving hormone therapy for prostate cancer

PURPOSE

A presentation on osteoporosis, obesity and obesity related disease at the Conference on Innovations and Challenges in Prostate Cancer: Prevention, Detection and Treatment is summarized.

MATERIALS AND METHODS

A focused literature review was done.

RESULTS

Gonadotropin-releasing hormone (GnRH) agonists decrease bone mineral density and increase fracture risk. GnRH agonists also increase weight and fat mass, and decrease lean body mass. Treatment related changes in body composition may contribute to fatigue and fracture risk. The phenotype of men with GnRH agonist shares some features with the insulin resistance syndrome, raising the possibility that GnRH may also increase the risk of diabetes mellitus and cardiovascular disease.

CONCLUSIONS

The routine use of GnRH agonists in men with long life expectancy increases the importance of understanding and preventing the unintended adverse effects of treatment. Some adverse effects have the potential to impact not only quality of life, but also noncancer mortality. Additional research is needed to characterize better the unintended effects of androgen deprivation therapy and develop optimal strategies to prevent osteoporosis, obesity and obesity related disease.

Osteoporosis prevalence and levels of treatment in primary care: the Australian BoneCare Study

The level of recognition and treatment of osteoporosis is not well characterized in primary care. In data from a large sample of postmenopausal women attending 927 primary care physicians, 29% of women reported one or more fractures after menopause. The great majority (72%) were not on any osteoporosis-specific therapy.

INTRODUCTION

Osteoporosis is often first recognized at the time of a low-trauma fracture. However, by this stage, the risk of subsequent fractures has already risen substantially. Moreover, in many countries, only a small proportion of women, who have already sustained fractures, receive a treatment shown to reduce this increased risk of further fractures.

MATERIALS AND METHODS

This project was initiated to examine the prevalence of osteoporotic fractures, risk factors for osteoporosis, and use of antifracture therapy among postmenopausal Australian women. More than 88,000 women from 927 primary care physicians returned over 69,358 surveys. Of these, 57,088 reported the presence of a postmenopausal fracture or risk factors.

RESULTS

Among these randomly selected postmenopausal women, 29% reported having had one or more low-trauma fractures after menopause (44% substantiated in current records). One-third of these women reported multiple fractures. The prevalence of all types of fractures, except rib and ankle, increased with age and low body weight. Those who reported fractures were also more likely to report early menopause, corticosteroid use, and a family history of osteoporosis. Moreover, those with vertebral fractures were more likely to record height loss, kyphosis, and back pain. Physical inactivity, low calcium intake, and smoking had no consistent relationship with any fracture outcome. Of the women who reported a fracture after menopause, only 28% were on any specific therapy for osteoporosis, and 7% were on calcium alone. Of those who had been told they had osteoporosis by a doctor, 40% were receiving specific osteoporosis therapy.

CONCLUSIONS

In this large study of postmenopausal Australian women attending primary care physicians, 29% reported at least one low-trauma fracture after menopause. Less than one-third of these women were on specific treatment for osteoporosis, and only 40% were ever told they had osteoporosis. Therefore, osteoporotic fractures are common in postmenopausal Australian women, and few, despite their substantially increased risk of further fractures, are on any specific anti-osteoporotic therapy. These data support the need for more effective education for the community and medical practitioners of the clinical significance of osteoporotic fractures and alternatives for treatment.

Strontium ranelate improves bone resistance by increasing bone mass and improving architecture in intact female rats

Strontium ranelate given to intact rats at doses up to 900 mg/kg/day increases bone resistance, cortical and trabecular bone volume, micro-architecture, bone mass, and total ALP activity, thus indicating a bone-forming activity and an improvement of overall bone tissue quality.

INTRODUCTION

Various anti-osteoporotic agents are available for clinical use; however, there is still a need for drugs able to positively influence the coupling between bone formation and bone resorption to increase bone mass and bone strength. Strontium ranelate (PROTELOS), a new chemical entity containing stable strontium (Sr), was tested for its capacity to influence bone quality and quantity.

MATERIALS AND METHODS

The long-term effects of strontium ranelate on bone were investigated in intact female rats treated with various doses of strontium ranelate (0, 225, 450, and 900 mg/kg/day) for 2 years. In a second series of experiments, the effects of 625 mg/kg/day were evaluated in intact male and female rats for the same period of time. Bone mineral mass and mechanical properties were evaluated at various skeletal sites (vertebra and femur), and bone tissue micro-architecture was evaluated by static histomorphometry at the tibio-fibular junction (cortical bone) and at the tibia metaphysis (trabecular bone). Plasma total alkaline phosphatase (ALP) activity and serum levels of insulin-like growth factor-I (IGF-I) were also assessed.

RESULTS

In female rats treated with strontium ranelate over 2 years, dose-dependent increases of bone strength and bone mass of the vertebral body (containing a large proportion of trabecular bone) and of the midshaft femur (containing mainly cortical bone) were detected without change in bone stiffness. Similar effects were observed in males at the level of the vertebra. This increase in mechanical properties was associated with improvements of the micro-architecture as assessed by increases of trabecular and cortical bone volumes and trabecular number and thickness. Finally, plasma total ALP activity and IGF-I were also increased in treated animals, compatible with a bone-forming activity of strontium ranelate.

CONCLUSION

A long-term treatment with strontium ranelate in intact rats is very safe for bone and improves bone resistance by increasing bone mass and improving architecture while maintaining bone stiffness.

The impact of compliance with osteoporosis therapy on fracture rates in actual practice

BACKGROUND

Clinical trials have demonstrated that drug therapy can reduce osteoporosis-related fracture risk in women over 50 years of age. Noncompliance could considerably limit the effectiveness observed in actual practice, however. The objective of this study was therefore to estimate fracture risk in relation to compliance with osteoporosis medication in actual practice.

METHODS

Demographic, prescription drug use, physician services, and hospitalization information for women with osteoporosis who were dispensed an osteoporosis medication between 1996 and 2001 was obtained from the Saskatchewan health data files. Compliance to treatment was defined as drug available to cover 80% of the time. Subsequent fractures were identified via hospitalizations or physician contacts with a relevant diagnostic or procedure code. The risk of fractures in relation to compliance was examined using a Cox proportional hazards model with time-dependent covariates. The impact of other patient characteristics, including age, having suffered a prior fracture, and prior use of osteoporosis medication and steroids, was also examined.

RESULTS

11,249 women suffering from osteoporosis were identified with a mean age at the time of the index prescription of 68.4 years and average follow-up of 2 years. The overall fracture rate was 4.5% per year. Patients who complied experienced a 16% lower fracture rate. This association was maintained within subgroups and after controlling for other patient characteristics that independently predict the fracture rate.

CONCLUSION

These results indicate that improving compliance in actual practice may significantly decrease osteoporosis-related fracture risk.

Nonpeptide alphavbeta3 antagonists. Part 11: discovery and preclinical evaluation of potent alphavbeta3 antagonists for the prevention and treatment of osteoporosis

3-(S)-Pyrimidin-5-yl-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5e) and 3-(S)-(methylpyrimidin-5-yl)-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5f) were identified as potent and selective antagonists of the alpha(v)beta(3) receptor. These compounds have excellent in vitro profiles (IC(50) = 0.07 and 0.08 nM, respectively), significant unbound fractions in human plasma (6 and 4%), and good pharmacokinetics in rat, dog, and rhesus monkey. On the basis of the efficacy shown in an in vivo model of bone turnover following once-daily oral administration, these two compounds were selected for clinical development for the treatment of osteoporosis.

RETRACTED: Comparative efficacy of hormone replacement therapy, etidronate, calcitonin, alfacalcidol, and vitamin K in postmenopausal women with osteoporosis: The Yamaguchi Osteoporosis Prevention Study

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor in Chief because of the stated concerns listed below. This article was accepted for publication by a previous editor and editorial board, at a time when submissions and documentation were in paper form, prior to the transition of The American Journal of Medicine to a digital submission and review process. These records are no longer extant and consequently we are unable to review the comments of the reviewers and editors involved at that time. We have attempted to contact the authors regarding these concerns and received no response. We are therefore retracting this article since the evidence presented below strongly argues for scientific misconduct. The integrity of these publications is severely compromised by wide-ranging and serious concerns about governance, ethics, authorship, implausible study conduct, implausible workload, discrepant participant numbers and treatment groups, impossible data, implausible data, implausible outcome data, and discrepant methodology.

Unmasking the osteoinductive effects of a G-protein-coupled receptor (GPCR) kinase (GRK) inhibitor by treatment with PTH(1-34)

The effects of GPCR systems in bone are regulated by a family of enzymes termed GRKs. We found that (1) GRK inhibition in osteoblasts has age-dependent effects on bone mass, and (2) the anabolic actions of GRK inhibition are revealed by treatment with PTH(1-34).

INTRODUCTION

The effects of G-protein-coupled receptor (GPCR) systems in bone are modulated by a family of enzymes termed GPCR kinases (GRKs). These enzymes directly phosphorylate GPCR substrate and desensitize receptor signaling. We previously found that expression of a GRK inhibitor in osteoblasts using transgenic (TG) technologies enhanced bone remodeling, and in turn, increased BMD in 6-week-old TG mice compared with non-TG littermate controls, presumably because of enhanced GPCR function. The aim of this study was to determine the age-dependent effects of the transgene.

MATERIALS AND METHODS

BMD was monitored in TG mice and in controls at 6-week, 3-month, and 6-month time-points. To determine if the transgene enhanced responsiveness of bone to parathyroid hormone (PTH), we measured cyclic adenosine monophosphate (cAMP) generation by mouse calvaria ex vivo as well as the effects of treatment with PTH(1-34) on BMD, bone histomorphometry, and expression of the PTH-responsive gene RANKL in both TG mice and non-TG controls.

RESULTS

Consistent with our previous findings, we found that BMD was increased in TG mice compared with controls at 6 weeks of age. The increase in BMD was most prominent in trabecular-rich lumbar spine and was not observed in cortical bone of the femoral shaft. In contrast to younger animals, however, BMD in older TG mice was not statistically different compared with non-TG mice at 3 months of age and was similar to non-TG animals at 6 months of age. The GRK inhibitor seemed to promote GPCR activation in older mice, however, because (1) PTH-induced cAMP generation by mouse calvaria ex vivo was enhanced in TG mice compared with controls, (2) GRK inhibition increased responsiveness of lumbar spine to the osteoinductive actions of PTH(1-34), and (3) the enhanced anabolic effect of PTH(1-34) was associated with increased expression of the PTH-responsive gene RANKL in calvaria of the TG animals. Bone histomorphometry confirmed that PTH(1-34) increased trabecular bone volume in TG mice and found that this increase in bone mass was caused by enhanced bone formation, predominantly as a result of an increase in the mineral apposition rate (MAR).

CONCLUSIONS

These data suggest that the anabolic effects of GRK inhibition are age dependent. The osteoinductive actions of the GRK inhibitor are, however, unmasked by treatment with PTH(1-34).

Loss of bone density with inhaled triamcinolone in Lung Health Study II

Inhaled glucocorticosteroids (ICS) are commonly prescribed for chronic obstructive pulmonary disease. No adverse effect on bone mineral density (BMD) has been proven. In a randomized double-blind, placebo-controlled trial at seven centers in North America, we recruited 412 current smokers or recent quitters with mild to moderate chronic obstructive pulmonary disease. They used inhaled triamcinolone acetonide, 600 mcg, or placebo, twice daily. We measured femoral neck and lumbar spine BMD at baseline and after 1 and 3 years, and serum osteocalcin at baseline, 3 months, 1 year, and 3 years. After 3 years, BMD at the femoral neck decreased 1.78% more with ICS than with placebo (p < 0.001). More participants in the ICS group experienced 6% or more loss of femoral neck BMD (p = 0.002). Lumbar spine BMD increased in the placebo group by 0.98% but decreased by 0.35% in the ICS group (a difference of 1.33%, p = 0.007). Changes in osteocalcin did not correlate with changes in BMD. Fractures, lost height, or osteoporosis diagnoses were not increased among ICS users compared with placebo users. In summary, the use of inhaled triamcinolone acetonide was associated with loss of BMD at the femoral neck and lumbar spine after 3 years of treatment.

Nonpeptide αvβ3 antagonists. Part 10: In vitro and in vivo evaluation of a potent 7-methyl substituted tetrahydro-[1,8]naphthyridine derivative

Subtle modifications were incorporated into the structure of clinical candidate 1. These changes were designed to maintain potency and selectivity while inducing changes in physical properties leading to improved pharmacokinetics in three species. This approach led to the identification of 4 as a potent, selective alphaVbeta3 receptor antagonist that was selected for clinical development based on an improved PK profile and efficacy demonstrated in an in vivo model of bone turnover.

Bone loss and the evolving role of bisphosphonate therapy in prostate cancer

Androgen deprivation therapy (ADT) can result in significant loss of bone mineral density (BMD) but to date, there are no prospective studies that document the true severity of bone loss and resulting fracture rates. In the general population, however, the incidence of low BMD is increasing in elderly men. Men suffer more morbidity and mortality from fractures associated with low BMD than women. Problems of underdiagnosis and undertreatment in men can be addressed with enhanced awareness of the risk factors for bone loss in men and the available treatment options. Guidelines for diagnosis of low BMD in women can probably be applied to men. Treatment options have not been studied as extensively in men. For men treated with ADT for prostate cancer, however, use of intravenous zoledronic acid at the initiation of ADT has been shown to prevent and even reverse bone loss. Although the routine use of bisphosphonates to prevent bone loss is not yet recommended, zoledronic acid is a logical choice of therapy in men who have low BMD at baseline or who develop bone loss during the course of therapy. In addition to its effects on BMD, zoledronic acid has also been shown to decrease skeletal morbidity in men with metastatic hormone-refractory prostate cancer. Whether zoledronic acid or other bisphosphonates might actually prevent or delay the development of bone metastases remains to be studied in randomized clinical trials.

Undertreatment of osteoporosis in residents of nursing homes: population-based study with use of the Systematic Assessment of Geriatric Drug Use via Epidemiology (SAGE) database

OBJECTIVE

To determine the proportion of nursing home residents >65 years of age with osteoporosis who were receiving antiosteoporosis pharmacotherapy and to identify the predictors of administration of such drugs.

METHODS

We identified 29,357 patients with osteoporosis documented on the Minimum Data Set collected on residents of all nursing home facilities in 5 states during the period from 1992 through 1996. A multiple logistic regression model was used for analysis, with the dependent variable being use of any antiosteoporosis drug.

RESULTS

Among the nursing home residents with osteoporosis, 25% received antiosteoporosis drugs. Women were more likely than men to receive antiosteoporosis drugs (adjusted odds ratio [OR], 1.41; 95% confidence interval [CI], 1.26 to 1.57). Both increasing age and level of cognitive impairment were inversely related to receipt of antiosteoporosis drugs. A history of fracture or falls was not predictive of use of such drugs. Treatment was less likely for nursing home residents with > or = 6 medical conditions (OR 0.55, 95% CI 0.51 to 0.59); those admitted to a nursing home from a hospital (OR 0.86, 95% Cl 0.80 to 0.92); and those with a terminal prognosis (OR 0.60,95% CI 0.42 to 0.87).

CONCLUSION

The majority of nursing home residents with osteoporosis in this study did not receive drug therapy for this disabling and treatable disease. Although acceptable reasons may exist in some of these residents,others--especially the oldest old--may not be receiving adequate care.

The older orthopaedic patient: general considerations

People older than 65 years are more likely to need elective and emergent orthopaedic surgery compared with younger persons. They also experience significant benefits. Although age-related changes increase the risk of perioperative complications, understanding those changes allows prevention or at least early recognition and treatment when problems arise. Because of comorbidities, older persons take more medications that need to be managed in the perioperative period. Care could be simplified if patients were to bring their medications to the preoperative evaluation. Central nervous system sensitivity to certain pain medications (meperidine and propoxyphene) means that these drugs are best avoided as good alternatives exist (morphine and oxycodone). Adverse reactions to drugs are an important cause of acute confusion (delirium) that often complicates orthopaedic care. Early mobilization after surgery, avoiding certain drugs, avoiding restraints (including Foley catheters), attending to hydration, promoting normal sleep, compensating for sensory disorders, and stimulating daytime activities can prevent delirium. Patients with dementia are more likely to have delirium develop and, like many older people, will present special challenges in communication and decision making. Including family members in discussions may be helpful in ensuring truly informed consent.

Recognizing and treating glucocorticoid-induced osteoporosis in patients with pulmonary diseases

Glucocorticoids are frequently used to treat patients with pulmonary diseases, but continuous long-term use of glucocorticoids may lead to significant bone loss and an increased risk of fragility fractures. Patients with certain lung diseases, regardless of pharmacotherapy-particularly COPD and cystic fibrosis-and patients waiting for lung transplantation are also at increased risk of osteoporosis. Fragility fractures, especially of the hip, will have substantial effects on the health and well-being of older patients. Vertebral collapse and kyphosis secondary to glucocorticoid-induced osteoporosis (GIO) may affect lung function. Identification of patients with osteopenia, osteoporosis, or fragility fractures related to osteoporosis is strongly recommended and should lead to appropriate treatment. Prevention of GIO in patients receiving continuous oral glucocorticoids is also recommended. In patients receiving either high-dose inhaled glucocorticoids or low- to medium-dose inhaled glucocorticoids with frequent courses of oral glucocorticoids, bone mineral density measurements should be performed to screen for osteopenia and osteoporosis. A bisphosphonate (risedronate or alendronate), calcium and vitamin D supplementation, and lifestyle modifications are recommended for the prevention and treatment of GIO.

A review of osteoporosis in men: implications for practice

This article discusses the issue of osteoporosis from a male perspective. Osteoporosis is often seen as a woman's disease; however, there are a significant number of men who suffer from osteoporosis and the effects of the disease can have implications for the man's physical, social and psychological well-being. The reasons why osteoporosis may be increasing in the male population are discussed. The possible causes of osteoporosis as well as the risk factors that may put men at danger of contracting the illness are outlined. Bone density is an important factor related to the development of osteoporotic fractures - methods of measuring bone density using dual energy X-ray absorptiometry are provided, as are other important investigations that will be needed. The management and treatment of the male patient with osteoporosis and the role of the nurse are detailed.