Circulating α-Klotho Counteracts Transforming Growth Factor-ß-Induced Sarcopenia.

α-Klotho is a longevity-related protein. Its deficiency shortens lifespan with prominent senescent phenotypes, including muscle atrophy and weakness in mice. α-Klotho has two forms: membrane α-Klotho and circulating α-Klotho (c-α-Klotho). Loss of membrane α-Klotho impairs a phosphaturic effect, thereby accelerating phosphate-induced aging. However, the mechanisms of senescence on c-α-Klotho loss remain largely unknown. Herein, with the aging of wild-type mice, c-α-Klotho declined, whereas Smad2, an intracellular transforming growth factor (TGF)-ß effector, became activated in skeletal muscle. Moreover, c-α-Klotho suppressed muscle-wasting TGF-ß molecules, including myostatin, growth and differentiation factor 11, activin, and TGF-ß1, through binding to ligands as well as type I and type II serine/threonine kinase receptors. Indeed, c-α-Klotho reversed impaired in vitro myogenesis caused by these TGF-ßs. Oral administration of Ki26894, a small-molecule inhibitor of type I receptors for these TGF-ßs, restored muscle atrophy and weakness in α-Klotho (-/-) mice and in elderly wild-type mice by suppression of activated Smad2 and up-regulated Cdkn1a (p21) transcript, a target of phosphorylated Smad2. Ki26894 also induced the slow to fast myofiber switch. These findings show c-α-Klotho's potential as a circulating inhibitor counteracting TGF-ß-induced sarcopenia. These data highlight the potential of a novel therapy involving TGF-ß blockade to prevent sarcopenia.

Effect of Bone Resorption Inhibitors on Serum Cholesterol Level and Fracture Risk in Osteoporosis: Randomized Comparative Study Between Minodronic Acid and Raloxifene.

The positive link between osteoporosis and hypercholesterolemia has been documented, and bone resorption inhibitors, such as nitrogen-containing bisphosphonates (N-BP) and selective estrogen receptor modulators (SERMs), are known to reduce serum cholesterol levels. However, the relationship between the baseline cholesterol level and incident fracture rate under the treatment using the bone resorption inhibitors has not been documented. We investigated the relation between vertebral fracture incident and the baseline cholesterol levels and cholesterol-lowering effect of N-BP and SERM in osteoporosis through a prospective randomized open-label study design. Patients with osteoporosis (n = 3986) were allocated into two groups based on the drug used for treatment: minodronic acid (MIN) (n = 1624) as an N-BP and raloxifene (RLX) as an SERM (n = 1623). Serum levels of cholesterol and incidence of vertebral fracture were monitored for 2 years. The vertebral fracture rates between the two groups were compared using the pre-specified stratification factors. The patients receiving MIN with baseline low-density lipoprotein (LDL)-cholesterol level of ≥ 140 mg/dL, high-density lipoprotein cholesterol level < 40 mg/dL, age group of ≥ 75 years, and T score of BMD ≥ -3 SD had significantly lower vertebral fracture rates than those receiving RLX (incidence rate ratios (IRR) 0.45 [95% confidence interval (CI) 0.30 0.75, p = 0.001], 0.25 [95% CI 0.09 0.65, p = 0.005], 0.71 [95% CI 0.56 0.91, p = 0.006], 0.47 [95% CI 0.30 0.75, p = 0.0012], respectively). The cholesterol-lowering effect was stronger in the RLX group than in the MIN group, regardless of prior statin use. These results indicated that MIN treatment was more effective in reducing fracture risk in patients with higher LDL cholesterol levels, although its cholesterol-lowering ability was lesser than the RLX treatment.Trial registration University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR), No. UMIN000005433; date: April 13, 2011.

Impact of bone mineral density in reducing fracture risk in patients receiving alendronate plus alfacalcidol therapy.

BACKGROUD: Changes in bone mineral density (BMD) are a potential surrogate marker for fracture endpoints in clinical trials. However little is known whether the increase in BMD in response to combination treatment with alendronate plus alfacalcidol is associated with fracture risk reduction. We aimed to evaluate the impact of BMD on fracture risk in osteoporosis patients, using the data from the randomized clinical trial comparing alendronate plus alfacalcidol with alendronate alone. METHODS: We selected 412 patients with two or more prevalent vertebral fractures and who had BMD measurements at baseline and after 6, 12, and/or 24 months out of 2022 patients from the database of the Japanese Osteoporosis Intervention Trial. Patients in this subset who received combination treatment with alendronate plus alfacalcidol had shown a lower risk of fracture than patients treated with alendronate alone. We used Poisson regression model analysis to calculate the proportion of treatment effect (PTE) that was attributable to BMD increases in patients receiving combination treatment. RESULTS: The highest PTE attributable to changes in BMD was 1.2% in patients with a BMD increase of 3% or more in the lumbar spine. For BMD measurements of the radius, the highest PTE was 2.8% with a BMD increase of 0% or more. For BMD measurements of the metacarpal bone, the highest PTE was 1.2% with a BMD increase of 3% or more. In patients with a BMD greater than or equal to 70% of the young adult mean in the lumbar spine, the PTE attributable to BMD was 0.2%. In patients with a BMD greater than or equal to 70% of the young adult mean in the radius, the PTE attributable to BMD was 0.3%. CONCLUSIONS: The additional effects of alfacalcidol in reducing fracture risk do not likely result from increased BMD; other mechanisms remain a possibility.

Study design of multi-center, open-label randomized controlled, head-to-head trial comparing minodronic acid and raloxifene: Japanese Osteoporosis Intervention Trial (JOINT)-04.

We planned to conduct multi-center, open-labeled, blinded-endpoints, head-to-head randomized trial of minodronate and raloxifene to compare incidences of vertebral and non-vertebral fractures. The study is the Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-4). Here, we present the pre-fixed study design. The inclusion criteria are ambulatory older women with osteoporosis, aged > 60 years, and without pre-specified risk factors for secondary osteoporosis and dementia. The subjects who meet selection criteria will be randomly allocated to the raloxifene (60 mg/day) or minodronate (1 mg/day or 50 mg/4 weeks) groups using the central registry. The co-primary endpoints are osteoporotic (vertebral, humeral, femoral, and radial), vertebral, and major osteoporotic (clinical vertebral, humeral, femoral, and radial) fractures. Furthermore, we plan to use the Hochberg procedure to preserve an overall type 1 error rate. In addition, changes in bone mineral density (BMD), hip-structure analysis (HSA) variables, height, bone turnover markers, serum cholesterol and triglyceride concentrations, dental health questionnaire, fall frequency, fall risk index, nursing care level, physical function, quality of life (QOL), and safety profiles were assessed as secondary endpoints. To detect 24% reduction of major osteoporotic fractures with 80% power and a two-sided significance level of 5% with a 2-year observation period, 1734 patients/treatment arm would be required. Subgroup analysis stratified to the following factors age, body mass index, BMD, 25-hydroxyvitamin D concentration, estimated glomerular filtration rate (eGFR), prevalent vertebral fracture number, hypertension status, and diabetes mellitus is pre-specified. The protocol is registered in the trial registry system, and the trial identification number is UMIN000005433.

Comparison of concurrent treatment with vitamin K2 and risedronate compared with treatment with risedronate alone in patients with osteoporosis: Japanese Osteoporosis Intervention Trial-03.

The aim of this study was to investigate the efficacy of concurrent treatment with vitamin K2 and risedronate compared with treatment with risedronate alone in patients with osteoporosis and to explore subsets of patients for which concurrent treatment is particularly efficacious. Women with osteoporosis aged 65 years or older were recruited from 123 institutes in Japan and allocated to take either vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate (2.5 mg/day or 17.5 mg/week) alone. The primary end point was the incidence of any fracture (vertebral and nonvertebral). The secondary end points were bone mineral density, height, undercarboxylated osteocalcin concentration, quality of life, and safety. Over a 2-year follow-up, vertebral or nonvertebral fractures occurred in 117 or 22 sites respectively among 931 patients in the risedronate and vitamin K2 group and in 104 or 26 sites respectively among 943 patients in the risedronate alone group. The rates of any incident fracture were similar between the two groups (incidence rate ratio 1.074, 95 % confidence interval 0.811-1.422, p = 0.62), implying that the primary end point was not met. There were no differences in the degree of increase in bone mineral density between the two groups. Undercarboxylated osteocalcin concentration decreased from 5.81 ± 3.93 ng/mL to 2.59 ± 1.52 ng/mL at 6 months in the risedronate and vitamin K2 group, whereas the change in the risedronate alone group was minimal (from 5.96 ± 4.36 ng/mL to 4.05 ± 3.40 ng/mL at 6 months) (p < 0.01). The treatment discontinuation rate was higher in the risedronate and vitamin K2 group than in the risedronate alone group (10.0 % vs 6.7 %). No unknown adverse drug reactions were reported. In conclusion, concurrent treatment with vitamin K2 and risedronate was not efficacious compared with monotherapy with risedronate in terms of fracture prevention.

Once-Weekly Injection of Low-Dose Teriparatide (28.2 µg) Reduced the Risk of Vertebral Fracture in Patients with Primary Osteoporosis.

We conducted a randomized, double-blind trial to assess the effect of 28.2 µg teriparatide versus placebo (1.4 µg teriparatide) on reduction of the incidence of vertebral fractures. Individuals enrolled in this study included patients with primary osteoporosis with one to five vertebral fractures and capable of self-supported walking. Attention was focused on incident vertebral fractures, change in bone mineral density (BMD) of the lumbar spine, and safety. A total of 316 subjects participated in the study, which lasted up to 131 weeks. Incident vertebral fractures occurred in 3.3% of subjects in the 28.2 µg teriparatide-treated group and 12.6% of subjects in the placebo group during the 78-weeks study period. Kaplan-Meier estimates of risk after 78 weeks were 7.5 and 22.2 % in the teriparatide and placebo groups, respectively, with a relative risk reduction of 66.4% by teriparatide (P = 0.008). Lumbar BMD in the 28.2 µg teriparatide group increased significantly by 4.4 ± 4.7 % at 78 weeks, which was significantly higher than the corresponding data in the placebo group (P = 0.001). Adverse events were observed in 86.7% of individuals in the teriparatide group and 86.1% of those in the placebo group. In conclusion, weekly injection of a low-dose of teriparatide (28.2 µg) reduced the risk of incident vertebral fractures and increased lumbar BMD.

Once-weekly teriparatide reduces the risk of vertebral fracture in patients with various fracture risks: subgroup analysis of the Teriparatide Once-Weekly Efficacy Research (TOWER) trial.

Once-weekly teriparatide (human parathyroid hormone [1-34]) (56.5 µg for 72 weeks) injections provided a vertebral fracture risk reduction in Japanese osteoporotic patients evaluated in the Teriparatide Once-Weekly Efficacy Research (TOWER) trial. Using data from the TOWER trial, a subgroup analysis was performed to study the efficacy of once-weekly teriparatide for a variety of baseline clinical risk factors in placebo (n = 281) and teriparatide (n = 261) groups. Significant fracture risk reductions were observed in the subgroups of individuals aged <75 years [relative risk (RR) 0.06, p = 0.007] and ≥75 years (RR 0.32, p = 0.015). A significant risk reduction was observed among patients with prevalent vertebral fracture in the subgroup with 1 (RR 0.08, p = 0.015) or ≥2 (RR 0.29, p = 0.009) prevalent vertebral fractures, and in those with grade 3 deformity (RR 0.26, p = 0.003). Significant risk reduction was observed in the subgroup with lumbar bone mineral density (BMD) < -2.5 SD (RR 0.25, p = 0.035). In the teriparatide group, no incident fracture was observed in the subgroups with a prevalent vertebral fracture number of 0, with grade 0-2 vertebral deformity, or with lumbar BMD ≥2.5 SD. Significant risk reduction was observed in all of the bone turnover marker and estimated glomerular filtration rate subgroups. In conclusion, once-weekly 56.5 µg teriparatide injection reduced the vertebral fracture risk in patients with varying degrees of fracture risk, age, vertebral fracture number and grade, bone turnover level, and renal function.

Design of a randomized clinical trial of concurrent treatment with vitamin K2 and risedronate compared to risedronate alone in osteoporotic patients: Japanese Osteoporosis Intervention Trial-03 (JOINT-03).

Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates possibly interfere with vitamin K activation. This is a prospective, multi-center, open-labeled, randomized trial of the efficacy of concurrent treatment with vitamin K2 and risedronate compared with risedronate alone and to explore subsets of patients for which concurrent treatment is particularly efficacious (trial identification number UMIN000000991). Inclusion criteria are women who meet the criteria for pharmacological therapy for osteoporosis, aged ≥65 years, have any of pre-specified risk factors, can walk unassisted, and are able to answer questionnaires. Exclusion criteria are prior warfarin use, secondary osteoporosis or non-osteoporotic metabolic bone diseases, contraindication for vitamin K2 and risedronate, hyper- or hypoparathyroidism, mental disorders, prevalent vertebral fracture at ≥6 sites, severe degenerative spinal deformation between T4 and L4, serious heart, liver, or kidney disease, or bisphosphonate use within the previous 6 months. Patients were recruited from 123 institutes between January 2008 and February 2010, and allocated to vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate alone (2.5 mg/day or 17.5 mg/week) groups. Primary endpoint is a vertebral or non-vertebral fracture. Secondary endpoints are bone mineral density, height, undercarboxylated osteocalcin, JOQOL, EQ-5D and safety. A sample size of 910 subjects per group and 2-year follow-up will provide 80 % power to detect 35 % risk reduction for fracture, with a two-sided significance level of 5 %. Subgroup analysis stratified to adjustment factors for random allocation, body mass index, 25-hydroxyvitamin D, estimated glomerular filtration rate, grade of vertebral fracture, JOQOL, EQ-5D, and co-morbidity is pre-specified.

Eldecalcitol reduces the risk of severe vertebral fractures and improves the health-related quality of life in patients with osteoporosis.

Eldecalcitol reduces the risk of vertebral fractures in comparison to alfacalcidol in osteoporotic patients under vitamin D repletion. The aim of this study was to evaluate the effects of eldecalcitol on the spinal location of incident vertebral fractures, the severity of the fractures, and the changes in health-related quality of life (HRQOL) compared with those of alfacalcidol. The post hoc analysis has been performed on the data from the three-year, double-blind, randomized, head-to-head clinical trial of eldecalcitol versus alfacalcidol conducted in Japan. A total of 1054 patients were enrolled and randomized to take 0.75 µg eldecalcitol or 1.0 µg alfacalcidol daily for 3 years. The incidence of vertebral fractures was re-evaluated based on the location on the spine (upper T4-T10; lower T11-L4). The severity of vertebral fractures was determined by the semi-quantitative method, and the change in HRQOL was analyzed by using the Medical Outcomes Study Short Form 36-item questionnaire. The incidence of vertebral fracture at the lower spine was less in the eldecalcitol group than in the alfacalcidol group (p = 0.029). The incidence of severe vertebral fracture (Grade 3) was 3.8 % in the eldecalcitol group and 6.7 % in the alfacalcidol group, demonstrated a significant difference between the 2 groups (p = 0.036). Both eldecalcitol and alfacalcidol improved HRQOL in osteoporotic patients. Although no significant differences in each HRQOL scores were observed between eldecalcitol and alfacalcidol during the observational period, overall improvement from baseline of HRQOL scores were clearly observed in the eldecalcitol group. In conclusion, the incidences of lower spinal vertebral fractures and severe vertebral fractures were reduced further by eldecalcitol compared to alfacalcidol in the 3-year clinical trial. Daily treatment with eldecalcitol is effective in improving HRQOL, possibly owing to the reduced risk of lower spinal vertebral fractures and/or severe vertebral fractures.

Eldecalcitol is more effective for the prevention of osteoporotic fractures than alfacalcidol.

Eldecalcitol, a vitamin D3 analogue, significantly reduces the risk of new vertebral fractures and increases bone mineral density (BMD) more than does alfacalcidol. To determine the effect of eldecalcitol on the incidence of all fragility fractures caused by osteoporosis, we conducted post hoc analyses of the phase III clinical trial to evaluate the incidence of the osteoporotic fractures defined in the World Health Organization (WHO) Technical Report, and, also, the incidence of the major osteoporotic fractures utilized in the WHO Fracture Risk Assessment Tool (FRAX), and compared those in the eldecalcitol group with those in the alfacalcidol group. We also analyzed the incidence of osteoporotic fractures stratified by prespecified risk factors for fractures. Eldecalcitol treatment reduced the incidence of osteoporotic fractures defined by the WHO more than alfacalcidol treatment (18.6 % vs. 25.2 %; hazard ratio, 0.70; 95 % CI, 0.54-0.93). Prevalent vertebral fractures, two or more prevalent vertebral fractures, and total hip BMD T score less than -2.5 were the risk factors for new osteoporotic fractures with significant differences between the two treatments. Eldecalcitol also decreased the incidence of major osteoporotic fractures in the FRAX more than alfacalcidol (11.1 % vs. 16.3 %; hazard ratio, 0.66; 95 % CI, 0.46-0.94). In conclusion, treatment with eldecalcitol reduced the risk of fragility fractures caused by osteoporosis compared with alfacalcidol administration, which may result from a potent effect of eldecalcitol on BMD, bone structure, and bone turnover.

Number and severity of prevalent vertebral fractures and the risk of subsequent vertebral fractures in Japanese women with osteoporosis: results from the minodronate trial.

The aim was to evaluate the risk of new vertebral fractures with the increasing number and severity of prevalent vertebral fractures in women who received placebo or minodronate in a post hoc analysis of a 2-year randomized, double-blind, placebo-controlled study. The subjects were women aged 55-80 years old with 1-5 fragility fractures between the T4 and L4 vertebrae and bone mineral density <80 % of the young adult mean. A total of 704 subjects were randomized to take minodronate 1 mg (n = 359) or placebo (n = 345) once a day for 24 months. In the placebo group, the risk of incident vertebral fractures during the 2-year observational period was significantly related to the number and severity of prevalent vertebral fractures at baseline. The number of prevalent vertebral fractures was an independent risk factor for incident vertebral fracture in multivariate analysis. The relative risk reductions of vertebral fractures by minodronate treatment were 45.2, 61.1, and 64.2 % for patients with 1, 2, and ≥3 prevalent vertebral fractures, respectively, and 87.8, 64.6, and 50.1 % for patients with mild, moderate, and severe prevalent vertebral fractures, respectively. In conclusion, the number of prevalent vertebral fractures is an independent risk factor for incident vertebral fracture and minodronate reduces the fracture risk even in patients at a higher risk for fracture.

Study of the distribution by age group of serum cross-linked C-terminal telopeptide of type I collagen and procollagen type I N-propeptide in healthy Japanese women to establish reference values.

Osteoporosis prevention is an important public health goal. Bone turnover markers are clinically measured to assess bone strength. C-terminal telopeptide of type I collagen (CTX) is released when collagens degrade and serves as an indicator of bone resorption. Simple CTX immunoassays are now available. However, serum CTX (sCTX) reference ranges for Japanese women are lacking. Procollagen type I N-propeptide (intact P1NP) reflects osteoblast activity, serving as a marker of bone formation. Because sCTX and intact P1NP are clinically applied as bone turnover markers, we determined reference ranges for both sCTX and intact P1NP in healthy Japanese women. We collected 228 blood samples from healthy Japanese women aged 19-83 years, grouped by age and menopausal status. We measured sCTX and intact P1NP and examined their correlation. sCTX values differed significantly between the two consecutive decade groups encompassing 19-39 years of age, intact P1NP values between 20 and 30 s, between post-menopausal 50 and 60 s, and between pre-and post-menopausal women in their 50 s. The mean sCTX of 91 healthy pre-menopausal women was 0.255 (0.100-0.653) ng/mL, the intact P1NP in 90 women 33.2 (17.1-64.7) µg/L. Corresponding values for post-menopausal women were 0.345 (0.115-1.030) ng/mL and 41.6 (21.9-79.1) µg/L. sCTX correlated with intact P1NP. Bone resorption markers are measured to assess anti-resorption agents, bone formation markers to assess the effects of bone-forming agents. The sCTX and intact P1NP reference values determined herein, in healthy Japanese women, are expected to be useful for osteoporosis treatment, assessment of fracture risk, and other clinical applications.

Guidelines for the use of bone metabolic markers in the diagnosis and treatment of osteoporosis (2012 edition).

Recently the clinical application of bone metabolic markers has achieved significant progress and the measurements of these indices give us a better understanding of the pathogenesis of osteoporosis. Bone metabolic markers were adapted to select drug treatment for osteoporosis and to evaluate drug efficacy. Therefore, the proper application and assessment of bone metabolic markers in clinical practice is very important. To achieve these aims, the committee on the guidelines for the use of biochemical markers of bone turnover in osteoporosis authorized by the Japan Osteoporosis Society has summarized recent progress in bone markers and proposed the proper utilization of bone markers. Although the use of bone metabolic markers now has an important role in the daily management of osteoporosis, their use in Japan is still insufficient because of insurance coverage limitations. Since the Japan Osteoporosis Society first created the 2001 guidelines, new bone metabolic markers have been introduced into clinical practice. The availability of new osteoporosis treatments that promote bone formation has changed the clinical application of bone metabolic markers in current practice. Therefore, revisions to the current clinical practice are needed which led to the proposal to create these new 2012 guidelines.

Diagnostic criteria for primary osteoporosis: year 2012 revision.

In 1995, the Japanese Society for Bone and Mineral Metabolism (now the Japanese Society for Bone and Mineral Research) established the Osteoporosis Diagnostic Criteria Review Committee. Following discussion held at the 13th scientific meeting of the Society in 1996, the Committee, with the consensus of its members, proposed diagnostic criteria for primary osteoporosis. The Committee revised those criteria in 1998 and again in 2000. The Japanese Society for Bone and Mineral Research and Japan Osteoporosis Society Joint Review Committee for the Revision of the Diagnostic Criteria for Primary Osteoporosis aimed at obtaining international consistency and made a revised edition based on the new findings in 2012.

Efficacy of zoledronic acid in postmenopausal Japanese women with early breast cancer receiving adjuvant letrozole: 12-month results.

Aromatase inhibitor-associated bone loss has not been proved in the Japanese or Asian women. The aim of this study was to evaluate an upfront or delayed strategy of bone protection therapy with zoledronic acid administered at 4 mg every 6 months in postmenopausal Japanese women with early breast cancer to compare with results of the Z-FAST and ZO-FAST studies in western countries. Postmenopausal women with hormone receptor positive early breast cancer receiving adjuvant letrozole were randomly assigned to receive either upfront or delayed-start zoledronic acid (4 mg intravenously every 6 months). The delayed group received zoledronic acid when lumbar spine (L(2)-L(4)) bone mineral density (BMD) decreased to less than young adult mean -2.0SD or when a nontraumatic fracture occurred. The primary endpoint of this study was to compare the percent change in L(1)-L(4) BMD at 12 months between the groups. Secondary endpoints included percent changes in L(2)-L(4) and total hip (TH) BMD. The upfront and delayed groups included 94 and 95 patients, respectively. At 12 months, L(1)-L(4), L(2)-L(4), and TH BMD significantly decreased by 2.0, 2.4, and 2.4%, respectively, in the delayed group. L(1)-L(4) BMD was 4.9% higher in the upfront group than in the delayed group (95% CI 3.9-5.8%; p < 0.001). L(2)-L(4) BMD was 5.6% higher (95% CI 4.5-6.6%; p < 0.001), and TH BMD was 4.4% higher (95% CI 3.3-5.4%; p < 0.001). At 12 months, upfront zoledronic acid therapy prevented bone loss in postmenopausal Japanese women who were receiving adjuvant letrozole, confirming the Z-/ZO-FAST study results in western populations.

Three years of treatment with minodronate in patients with postmenopausal osteoporosis.

The objective of this study was to determine the safety and efficacy of long-term minodronate treatment in women with postmenopausal osteoporosis based on re-analysis of a phase III 2-year clinical trial with a 1-year extension. Women aged 55-80 years old with fragility fractures were enrolled and randomized to take 1 mg minodronate or placebo once a day in the original 2-year study. The subjects who completed the 2-year study were invited to participate in an additional 1-year extension in which all subjects were to receive minodronate. Finally, a total 380 subjects completed the extension study (186 from the placebo group and 194 from the minodronate group). Fracture results observed in the extension study were consistent with those observed in the first 2 years in minodronate group. In contrast, the placebo/minodronate group showed a decreased incidence of new vertebral fractures during year 3 compared to that in year 2. In the patients who received minodronate in the original 2-year study, lumbar bone mineral density (BMD) increased consistently during year 3 and bone turnover markers decreased within the first 6 months and remained constant thereafter over 3 years. Similar positive effects of minodronate on BMD and bone turnover markers occurred when therapy was initiated in the placebo/minodronate group. No new safety concerns observed during the extension period compared to the safety observations made during the 2-year study. It was concluded that daily administration of 1 mg oral minodronate is safe and well tolerated, and that the efficacy of this dose in reducing vertebral fracture risk in postmenopausal women over 2 years is sustained with continuing treatment.

Design of a pragmatic approach to evaluate the effectiveness of concurrent treatment for the prevention of osteoporotic fractures: rationale, aims and organization of a Japanese Osteoporosis Intervention Trial (JOINT) initiated by the Research Group of Adequate Treatment of Osteoporosis (A-TOP).

The aim of osteoporosis treatment is to prevent future fractures. Although concurrent treatment has been used very frequently for osteoporosis in clinical practice, there are no data on accurate and verified effectiveness of concurrent treatment for fracture prevention in patients with osteoporosis. To clarify the clinical usefulness of concurrent treatment, the Japan Osteoporosis Society has authorized the establishment of the A-TOP (Adequate Treatment of Osteoporosis) research group. The objective of this research is to establish a design for a clinical trial to prove whether concurrent treatment using both alfacalcidol (1-alpha-hydroxycholecalciferol) and alendronate is more effective as compared to treatment using alendronate alone in terms of fracture prevention. The present study was named JOINT (Japanese Osteoporosis Intervention Trial) and is based on a method using national, prospective, randomized, open-labeled, blinded endpoints focusing on postmenopausal osteoporosis with a high risk for fracture. The patients were mainly selected by practitioners and allocated randomly by a central registration system into two groups, of which one received 5 mg/day of alendronate alone, and the other received 1 µg/day of 1-alpha-hydroxycholecalciferol (alfacalcidol) in addition to the alendronate. The endpoints focused primarily on fracture prevention, and the patients' quality of life (QOL) and change in body height, as well as adherence and the adverse events of the treatments were evaluated secondarily. To obtain sufficient statistical power in the events during a 2-year observation period, the patients who are expected to have higher risk were selected to participate in this study, and it was decided that the final plan would involve 890 patients per group (two-sided alpha = 0.05, power = 0.8). Data collection began in November 2003. Correspondence regarding the registration of the investigator and the progress of the study was conducted through a web system from the Public Health Research Foundation to practitioners.

Current status of hip bone densitometry in Japan: a nationwide survey.

Hip fracture greatly impairs quality of life in patients with osteoporosis. Measurement of bone mineral density (BMD) in the hip, which is closely related to fracture risk, is therefore diagnostically important. Furthermore, since in some elderly individuals lumbar BMD may be overestimated because of vertebral fracture or spondylosis deformans, measurement of hip BMD is also important. However, hip BMD is unlikely to be measured as often as lumbar BMD in Japan. A questionnaire survey was conducted to determine how many institutions measure hip BMD. A total of 861 institutions responded to the survey, 596 (69%) of which performed hip bone densitometry. The number of such institutions per million population was calculated to be 4.7. Measurement of hip BMD was more frequent in university hospitals than in general hospitals, clinics, and non-medical institutions. Furthermore, 298 (51%) of 590 institutions measured hip BMD in more than 75% of all bone densitometry examinees. This is the first report on the current status of utilization of hip bone densitometry in Japan.

Changes in distribution of bone densitometry equipment from 1996 to 2006 in Japan.

Many types of bone densitometry equipment are available in Japan, but the numbers of such machines and the numbers of institutions that offer bone densitometry have not been clarified. We analyzed the data from annual surveys conducted by the Japan Osteoporosis Foundation from 1996 to 2006, and we obtained the following results on the use of densitometry equipment: (1) In 1996 there were 6,687 units of bone densitometry equipment in 6,483 institutions in Japan; in 2006 there were 16,371 units in 15,020 institutions. (2) In 2006, of the types of institutions with bone densitometry equipment, the number of clinics was the highest, followed in order by general hospitals, other types of institutions, screening institutions and university hospitals. Rates of increase in the installation of equipment in clinics and other types of institutions were high during the 11-year period from 1996. (3) From 1996 to 2006 the region of interest most frequently used for bone densitometry was the radius. However, during the 11-year period, the proportion of radial densitometry equipment in all institutions with bone densitometry equipment decreased, whereas the proportion of calcaneal densitometry equipment increased. (4) The number of dual-energy X-ray absorptiometry (DXA) units was the highest from 1996 to 2006. However, the proportion of DXA machines in all institutions with bone densitometry equipment decreased over the 11-year period, whereas the proportion of quantitative ultrasound (QUS) machines increased. (5) In 2006, bone densitometry equipment was available in 118 institutions per million Japanese people. Central DXA (spine/hip) equipment was available in 15 per million, radial DXA equipment in 63 per million, and calcaneal QUS equipment in 44 per million. (6) In 2006, among those places with bone densitometry equipment, 46% of university hospitals, 14% of general hospitals, 12% of screening institutions, 5% of clinics, and 6% of other types of institutions possessed more than one type of densitometry equipment. (7) In 2006, central DXA (spine/hip) was frequently available in university hospitals, radial densitometry equipment in general hospitals and clinics, and calcaneal densitometry equipment in screening institutions and other types of institutions.

Effect of minodronic acid hydrate on hip geometry in Japanese women with postmenopausal osteoporosis.

Dual-energy X-ray absorptiometry-based hip structural analysis was performed to evaluate the effect of a bisphosphonate, minodronic acid hydrate, on the geometry of the proximal femur in Japanese patients with osteoporosis. The subjects were 103 postmenopausal patients (average age 63.9 +/- 6.4 years) with primary osteoporosis. Minodronic acid hydrate was administered orally at a dose of 1 mg/day for 12 months. Significant early responses at 3-6 months after the start of administration were observed in all three regions of the proximal femur (narrow neck, intertrochanter, and shaft) in terms of bone density, geometry, and bone strength indices. The outcomes of therapy included a reduction of the internal diameter of the cortical bone (-0.1, -0.6, and -0.2% in the neck, intertrochanter, and shaft, respectively, at 12 months; not significant) and a significant increase in cortical thickness (3.1, 3.7, and 2.0% in the respective regions at 12 months). Furthermore, minodronic acid hydrate induced a significant enlargement of the cross-sectional bone area, which is related to compressive strength; a significant increase in cross-sectional moment of inertia and section modulus (SM 4.9, 5.8, and 2.9% in the neck, intertrochanter, and shaft, respectively, at 12 months; P < 0.001), which are related to the bending strength; and a significant reduction in buckling ratio (BR -3.0% (P < 0.001), -4.2% (P < 0.001), and -1.4% (P < 0.05) in the respective regions at 12 months), which reflects improved cortical stability. These findings show that minodronic acid hydrate reduces age-related endocortical bone resorption, leading to increased cortical thickness and sustained or enhanced bone strength.