Diagnostic criteria for primary osteoporosis: year 2000 revision

Comparison of the effects of alendronate and alfacalcidol on hip bone mineral density and bone turnover in Japanese men having osteoporosis or osteopenia with clinical risk factors for fractures

PURPOSE

The comparative effects of alendronate and alfacalcidol on bone mineral density (BMD) and bone turnover have already been established in postmenopausal women with osteoporosis. An open-labeled prospective study was conducted to compare the treatment effects of alendronate and alfacalcidol on hip BMD and bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures.

MATERIALS AND METHODS

One hundred twelve men with osteoporosis or osteopenia with clinical risk factors for fractures (mean age: 71.4 years) were randomly divided into two groups of 56 patients each: the alendronate (5 mg daily) and alfacalcidol (1 microg daily) groups. The BMD of the total hip, urinary level of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of bone-specific alkaline phosphatase (BSAP) were measured during the 12-month-treatment period.

RESULTS

Forty-five patients in the alendronate group and 42 patients in the alfacalcidol group completed the trial. Alendronate increased BMD (+2.3% at 12 months) following reductions in the urinary level of NTX (-46.4% at 3 months) and serum level of BSAP (-34.1% at 12 months), while alfacalcidol sustained BMD (-1.9% at 12 months) as well as the urinary level of NTX (+13.2% at 3 months) and serum level of BSAP (+1.8% at 12 months).

CONCLUSION

The present study confirmed that alendronate has better efficacy than alfacalcidol (active control) in increasing hip BMD and reducing bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures.

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

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

Association between bone mineral density and lifestyle factors or vitamin D receptor gene polymorphism in adult male workers: a cross-sectional study

OBJECTIVES

The aim of this cross-sectional study was to investigate the association between bone mineral density (BMD) and lifestyle factors, as well as the influence of vitamin D receptor (VDR) gene polymorphism, in adult male workers.

METHODS

The subjects were 524 male employees aged 23-49 years (37.3 +/- 5.4 years, mean +/- standard deviation) working at a large-scale integrated manufacturing facility in Japan. BMD was measured at the nondominant radius by dual-energy X-ray absorptiometry. Lifestyle information was obtained by a questionnaire at the same time, and genomic DNA was isolated from peripheral leukocytes.

RESULTS

The genotype frequencies of VDR gene polymorphism detected by Taq I digestion were 81.3%, 17.9%, and 0.8% for TT, Tt, and tt, respectively. BMD was 0.56 +/- 0.06 g/cm(2). Analysis of covariance with adjustment for age and body mass index (BMI) revealed that subjects who had a past history of exercise, current exercise from 3 to 7 days a week or daily alcohol intake showed significantly higher BMD than subjects without these features (0.56 +/- 0.06 versus 0.54 +/- 0.06, 0.58 +/- 0.06 versus 0.55 +/- 0.06, and 0.57 +/- 0.06 versus 0.55 +/- 0.06, respectively) (P < 0.05). Subjects who ate only 2 meals a day or smoked >/=21 cigarettes a day showed significantly lower BMD if they had the Tt or tt genotype than if they had the TT genotype (0.51 +/- 0.04 versus 0.56 +/- 0.06 and 0.51 +/- 0.05 versus 0.57 +/- 0.06, respectively) (P < 0.05).

CONCLUSIONS

These findings suggest that the influence of lifestyle on BMD differs according to VDR gene polymorphism in adult male workers.

The relationship between back pain and future vertebral fracture in postmenopausal women

STUDY DESIGN

Cross sectional and prospective observational study in Japanese postmenopausal women.

OBJECTIVE

The aim of the study was 2-fold. The first was to investigate what kind of comorbidities could be found in conjunction with back pain in Japanese postmenopausal women. The second was to investigate whether significant relationship between baseline back pain and future fracture exists or not.

SUMMARY OF BACKGROUND DATA

Back pain has been reported to be associated with vertebral degeneration or vertebral fracture. However, there has been no available data that indicates the relationship between back pain and future fracture risks.

METHODS

The subjects who visited their practitioner were examined for their prevalent back pain or pains in other site. Bone mineral density, body height, body weight, and serum parameter were measured at baseline, and comorbidities were investigated by interview. Fragility fractures were also assessed at baseline and then followed up with 1- to 2-year intervals. The correlation between back pain and baseline characteristics was investigated by logistic regression analysis. The hazard ratio of back pain to future vertebral fracture was estimated by multivariate Cox regression analysis.

RESULTS

A total of 899 postmenopausal ambulatory women (62.5 +/- 10.3 years old) were enrolled and 81 subjects were dropped out from the study within 1 year. The remaining 818 postmenopausal women (62.1 +/- 10.3 years) were followed-up for 5.7 +/- 3.5 years. Compared to the group without pain, the group with back pain had significantly higher age, lower bone mineral densities at lumbar spine and hip, and higher number of prevalent vertebral fractures. The back pain was significantly associated with rheumatic arthritis (odds ratio [OR]: 2.01, P < 0.05), prevalent vertebral fracture (OR: 4.60, P < 0.001) and osteoporosis (OR: 2.14, P < 0.001). A total of 189 future fractures were observed, of which the most frequent was vertebral fractures (78.3%). The fact that baseline back pain was a significant risk factor for time-dependent vertebral fractures (hazard ratio: 1.62, 95% confidence interval: 1.16-2.27, P = 0.005) was demonstrated by the Cox hazards model after adjusting for traditional risk factors, such as age, bone mineral density, and prevalence of vertebral fractures.

CONCLUSION

The data obtained in this study indicated that the back pain is significantly associated with osteoporosis and rheumatoid arthritis and that it can be useful predictor for future vertebral fracture risk in Japanese postmenopausal women in clinical settings.

Effect of daily oral minodronate on vertebral fractures in Japanese postmenopausal women with established osteoporosis: a randomized placebo-controlled double-blind study

SUMMARY; A randomized placebo-controlled trial was conducted to examine the effect of daily oral 1 mg minodronate on vertebral fractures in 704 postmenopausal women with established osteoporosis for 24 months. Minodronate treatment reduced vertebral fractures by 59% without serious adverse events. Minodronate is a safe and effective bisphosphonate for osteoporosis treatment.

INTRODUCTION

Minodronate increases bone mineral density (BMD) in postmenopausal osteoporotic patients. However, its efficacy in reducing osteoporotic fractures has not been tested.

METHODS

To examine anti-fracture efficacy and safety of daily oral minodronate in postmenopausal women with established osteoporosis, a randomized, double-blind, placebo-controlled trial was conducted in 704 postmenopausal women (55 to 80 years) with one to five vertebral fractures and low BMD. Subjects were randomly assigned to receive daily oral 1 mg minodronate (n = 359) or placebo (n = 345) for 24 months, with daily supplements of 600 mg calcium and 200 IU vitamin D(3).

RESULTS

Daily 1 mg minodronate for 24 months reduced the risk of vertebral fractures by 59% (95% CI, 36.6-73.3%). Furthermore, when fractures during the first 6 months were eliminated, the risk of vertebral fractures from 6 to 24 months was reduced by 74% in minodronate-treated group. Minodronate treatment also reduced height loss. Bone turnover markers were suppressed by about 50% after 6 months of minodronate treatment and remained suppressed thereafter. The overall safety profile including gastrointestinal safety was similar between the two groups.

CONCLUSIONS

Daily oral minodronate is safe, well-tolerated, and is effective in reducing vertebral fracture risk in postmenopausal women with established osteoporosis.

Bone mineral density measurement at both spine and hip for diagnosing osteoporosis in Japanese patients

In Japan, spinal dual-energy X-ray absorptiometry (DXA) has been commonly performed for diagnosing osteoporosis but scanning the proximal femur is not done widely. The latest Japanese guidelines for prevention and treatment of osteoporosis, revised in 2006, recommend bone mineral density (BMD) measurement at both spine and hip for diagnosing osteoporosis, although there have been no reports that proved the necessity of those measurements. One thousand forty-one women and 485 men with clinical suspicion of osteoporosis were enrolled in this study, and DXA was performed at both spine and hip. The proportions of the patients who had inconsistency between diagnosis of osteoporosis from spinal DXA and that of hip were estimated. As a result, 22% of women and 15% of men had an inconsistency with the diagnosis of osteoporosis using DXA at each measurement site. There was inconsistency in diagnosing osteoporosis using DXA at the spine and proximal femur measurement sites. Because spine and femoral DXA measurements complement each other in the diagnosis of osteoporosis, BMD measurement at both spine and hip should be performed for all Japanese patients who are suspected osteoporosis, regardless of age and sex.

Impact of spinal kyphosis on gastroesophageal reflux disease symptoms in patients with osteoporosis

SUMMARY

Spinal kyphosis has been speculated to participate in the increased frequency of gastroesophageal reflux disease (GERD) in patients with osteoporosis. The present study provides further evidence that increases in lumbar kyphosis and number of vertebral fractures represent very important risk factors for GERD in patients with osteoporosis.

INTRODUCTION

Osteoporosis and spinal kyphosis have been speculated to participate in the increased frequency of gastroesophageal reflux disease (GERD). The present study examined whether GERD in patients with osteoporosis is affected by spinal factors including spinal kyphosis in the presence of oral pharmacotherapies.

METHODS

Subjects comprised 112 patients with osteoporosis (mean age, 78 years) who responded to the Frequency Scale for Symptoms of GERD (FSSG) questionnaire, regardless of complaints. Relationships between total FSSG score and number of vertebral fractures, angles of kyphosis, use of bisphosphonates and nonsteroidal anti-inflammatory drugs (NSAIDs), and total number of oral medicines per day were evaluated. Logistic regression identified factors associated with GERD.

RESULTS

Bisphosphonates and NSAIDs did not affect total FSSG score. Total FSSG score showed significant positive correlations with total number of medicines (r = 0.283, p = 0.0025), angle of lumbar kyphosis (r = 0.576, p = 0.0001), and numbers of thoracic vertebral fractures (r = 0.214, p = 0.0232) and lumbar vertebral fractures (r = 0.471, p < 0.0001). Angle of lumbar kyphosis and number of lumbar vertebral fractures were identified by multivariate analysis as indices affecting the presence of GERD.

CONCLUSION

Increases in angle of lumbar kyphosis and number of lumbar vertebral fractures may represent very important risk factors for GERD in osteoporotic patients.

Epidemiology of lumbar osteoporosis and osteoarthritis and their causal relationship--is osteoarthritis a predictor for osteoporosis or vice versa?: the Miyama study

SUMMARY

In a 10-year follow-up of a population-based cohort of Japanese subjects, incidences of and causal relationships between osteoporosis (OP) and osteoarthritis (OA) at the lumbar spine were clarified. OP might reduce the risk of subsequent OA at the spine in women, but not in men.

INTRODUCTION

The aim of this study is to clarify the contribution of osteoarthritis (OA) to osteoporosis (OP) and vice versa.

METHODS

A population-based, epidemiological study was conducted in a Japanese rural community. From 1,543 participants aged 40-79 years, 200 men and 200 women were selected and followed up for 10 years. Bone mineral density measurements were repeated after 3, 7, and 10 years, and X-rays were repeated after 10 years.

RESULTS

The incidence of lumbar OP per 10,000 person-years for persons in their 40s, 50s, 60s, and 70s was 0, 0, 109.5, and 151.1 for men and 124.2, 384.0, 227.3, and 239.5 for women, respectively. The cumulative incidence of lumbar OA over 10 years aged 40-79 years was 25.8% in men and 45.2% in women. Cox's proportional hazards model showed no significant relationship between the presence of lumbar OA at the baseline and incidence of lumbar and femoral neck OP in both genders. A significant relationship was demonstrated between the presence of lumbar OP, not femoral neck OP, at the baseline and cumulative incidence of lumbar OA in women (odds ratio, 0.20; 95% confidence interval, 0.05-0.80; P = 0.02).

CONCLUSION

OP in women appears to reduce the future incidence of OA at the lumbar spine.

A double-blinded head-to-head trial of minodronate and alendronate in women with postmenopausal osteoporosis

INTRODUCTION

In a randomized, active-controlled, double-blinded, multicenter study, the efficacy and safety of minodronate were examined and compared to that of alendronate.

METHODS

A total of 270 postmenopausal osteoporotic women >or=45 years of age were randomized into the minodronate group (n=135) or alendronate group (n=135). Each subject received 1 mg minodronate or 5 mg alendronate once a day for 12 months.

RESULTS

Both treatment groups showed similar changes in BMD after 12 months. After 1 year of treatment, the lumbar spine BMD increased by 5.86% and 6.29% in the minodronate and alendronate groups, respectively, and the total hip BMD increased by 3.47% and 3.27%, respectively. Bone turnover markers were rapidly reduced within 1 month in both treatment groups. Urine DPD was significantly lower in the minodronate group than in the alendronate group at 6 months, and urine NTX was significantly lower in the minodronate group than in the alendronate group at 1 and 9 months. Both completion rates for the 12-month study and the overall incidence of clinical adverse events, including gastrointestinal events, were similar between the two groups.

CONCLUSIONS

The effects on lumbar and hip BMD and the safety profile of minodronate are comparable to those of alendronate. Minodronate is a promising new potent bisphosphonate for the treatment of osteoporosis.

Assessment of vertebral fracture risk and therapeutic effects of alendronate in postmenopausal women using a quantitative computed tomography-based nonlinear finite element method

A QCT-based nonlinear FEM was used to assess vertebral strength and mechanical parameters in postmenopausal women. It had higher discriminatory power for vertebral fracture than aBMD and vBMD. Alendronate effects were detected at 3 months, and marked bone density increases were noted in juxta-cortical areas compared to inner trabecular areas.

INTRODUCTION

QCT-based finite element method (QCT/FEM) can predict vertebral compressive strength ex vivo. This study aimed to assess vertebral fracture risk and alendronate effects on osteoporosis in vivo using QCT/FEM.

METHODS

Vertebral strength in 104 postmenopausal women was analyzed, and the discriminatory power for vertebral fracture was assessed cross-sectionally. Alendronate effects were also prospectively assessed in 33 patients with postmenopausal osteoporosis who were treated with alendronate for 1 year.

RESULTS

On the age and body weight adjusted logistic regression, vertebral strength had stronger discriminatory power for vertebral fracture (OR per SD change: 6.71) than areal BMD and volumetric BMD. The optimal point for the vertebral fracture threshold was 1.95 kN with 75.9% sensitivity and 78.7% specificity. At 3 months, vertebral strength significantly increased by 10.2% from baseline. The minimum principal strain distribution showed that the area of high fracture risk decreased. At 1 year, the density of the inner cancellous bone increased by 8.3%, while the density of the juxta-cortical area increased by 13.6%.

CONCLUSIONS

QCT/FEM had higher discriminatory power for vertebral fracture than BMD and detected alendronate effects at 3 months. Alendronate altered density distributions, thereby decreasing the area with a high fracture risk, resulting in increased vertebral strength.

Effect of intermittent systemic corticosteroid on bone metabolism in bronchial asthma patients

The purpose of this study was to assess the effect on bone mineral density (BMD) of systemic corticosteroid (SCS) intermittently administered for rescue from asthmatic exacerbation. Through digital image processing and calculation of four other indices, BMD was compared in groups of asthmatic patients receiving inhaled corticosteroid (ICS) alone or ICS plus intermittent SCS. We defined SCS as intermittent administration of the equivalent of 1 mg/day prednisolone in the management of asthma exacerbations during the previous 1 year. Serum NTX, a bone resorption marker, was significantly higher (p = 0.02) in the SCS group than the ICS group. SCS had no effect on BMD, although the frequency of patients at "high-risk" for osteoporosis according to the Female Osteoporosis Self-assessment Tool for Asia (FOSTA) tended to be higher in the SCS group (35%) than in the ICS (28%) or control (10%) group. Because patients in the ICS group already had impaired respiratory function due to repeated asthma exacerbations, it was difficult to determine whether it was asthma itself or SCS that is the risk factor for osteoporosis. In addition, the response of biochemical markers of bone turnover to intermittent SCS remains unclear and likely differs from that elicited by high-dose, short-term, or continuous SCS. That said, relatively low-dose intermittent administration of SCS raised levels of bone resorption markers, which likely reflects altered bone metabolism. Taken together, these findings suggest that, without consideration of its effects on bone, SCS administration should be avoided.

Pre-B-cell leukemia homeobox 1 (PBX1) shows functional and possible genetic association with bone mineral density variation

Bone mineral density (BMD) is one of the major determinants of risk for osteoporotic fracture. Multiple studies reveal that peak bone mass is under strong genetic influence. One of the major susceptibility loci for peak spine BMD has been mapped to chromosome 1q21-q23 in the Caucasian population. We have previously replicated this finding in Southern Chinese pedigrees and detected a maximum multipoint log of odds (LOD) score of 2.36 in this region. To further fine-map this region, 380 single-nucleotide polymorphic (SNP) markers were genotyped in 610 sibpairs from 231 families. Several markers were identified in the association analysis as important candidates underlying BMD variation. Among them, successful replication was demonstrated for SNPs in pre-B-cell leukemia homeobox 1 (PBX1) gene in two other unrelated case-control cohorts. The functional role of PBX1 in bone metabolism was examined in vitro using human bone-derived cells (HBDC) and murine MC3T3-E1 pre-osteoblasts. PBX1 mRNA was constitutively expressed in both HBDC and MC3T3-E1 cells. Immunostaining revealed that PBX1 is localized in the nucleus compartment. Silencing of PBX1 by RNAi in MC3T3-E1 cells decreased the expression of Runx2 and Osterix, the critical transcription factors for osteogenesis, but accelerated cell proliferation and bone nodule formation. Overall, our data suggest a genetic and functional association of PBX1 with BMD.

Association between lumbar bone mineral density and vascular stiffness as assessed by pulse wave velocity in postmenopausal women

Recent studies have showed a significant correlation between vascular calcification and bone mineral density (BMD). Therefore, an investigation was carried out on the association between arterial stiffness, lumbar BMD and bone metabolic markers in Japanese postmenopausal women. Brachial-ankle PWV (baPWV) and BMD of the lumbar spine and serum bone-specific alkaline phosphatase (BAP) levels in 143 postmenopausal women were measured, where there was a significant negative correlation between baPWV and BMD (r = -0.21; P = 0.0135). An additional analysis included the remaining 75 subjects, but excluded subjects with hypertension and obesity. Here, a more negative correlation between baPWV and BMD (r = -0.315; P = 0.006), and a positive correlation between baPWV and BAP (r = 0.248; P = 0.032) were also significant. A group analysis, where the women were age matched and stratified into three groups of different bone density, i.e., normal BMD, osteopenic and osteoporotic, were further made. This showed lower PWV values in the normal BMD group than in the other two groups. A study also showed that the tertile with the highest BAP was associated with significantly higher PWV values than the other tertiles. However, when the multiple linear regression analysis was carried out, there was no correlation between PWV and BAP values. Low BMD and arterial stiffness show some correlation, suggesting that BAP may reflect the degree of arterial stiffness present.

Contributions of 25-hydroxyvitamin D, co-morbidities and bone mass to mortality in Japanese postmenopausal women

It was reported that low bone mineral density (BMD), osteoporotic fractures and low serum 25-hydroxyvitamin D (25-OHVD) levels increase the risk of mortality in elderly Caucasian people. However, there is no data available on the relationship between bone mineral density or 25-OHVD levels and mortality in elderly Asian women. To determine whether or not low bone mineral density (BMD) or low 25-OHVD levels contribute to increased mortality risk, we conducted a prospective observational study in 1232 ambulatory postmenopausal female volunteers. Information was obtained from the subjects on baseline BMD, the serum levels of biochemical indices including 25-OHVD, prevalent fractures, co-morbidities and lifestyle variables. The participants were observed for a total of 6.9+/-3.6 years (mean+/-SD) and a total of 107 participants (8.7%) were dead during the observation. Mortality was assessed and confirmed on the certificates or hospital records or information from their family. In addition to traditional risks for mortality, such as age (Hazard ratio, 1.73, 95% CI, 1.51-1.98, P<0.01), 25-OHVD level <50 nmol/l (HR 2.17, 1.27-3.72, P=0.01), prevalent malignancies (HR 5.60, 3.36-9.31, P<0.01) and existing osteoporosis (HR 2.14, 1.22-3.75, P=0.01) were found to be significant independent risk factors for all-cause mortality by using multivariate Cox's regression analysis. It is suggested that prevalent osteoporosis, prevalent malignancy or lower levels of 25-OHVD represent powerful risk factors for mortality.

Age-related distribution of bone and skeletal parameters in 1,322 Japanese young women

We explored factors that could serve as indices for therapeutic intervention aimed at prevention of osteoporosis. In this cross-sectional study, we investigated the timing of peak bone mass (PBM) in 1,322 Japanese women aged 12-30 years old. We measured height, body weight, bone mineral density (BMD), bone mineral content (BMC), and bone area at the lumbar spine and total hip, as well as the blood markers calcium, phosphorus, and the bone metabolic markers bone alkaline phosphatase (BAP) and type I collagen cross-linked N-telopeptide (NTX). All measurements were standardized with the mean at age 18 defined as 100% to identify age-related differences. In the total hip, BMD peaked at age 18, while, in the lumbar spine, BMD peaked at age 29, of which 99.8% was attained at age 18, suggesting that peak BMD was attained at age 18 at both the total hip and lumbar spine. No age difference was observed in serum calcium, while there was a 15.1% decrease between ages 12 and 18 in serum phosphorus. There were 273.8% and 208.5% decreases in serum BAP and NTX, respectively, between ages 12 and 18, while these levels remained constant thereafter, suggesting that bone and calcium metabolism are constant between ages 19 and 30. Factors that had stronger correlations with BMD, BMC, and bone area from 12 years to 18 years were height and body weight. PBM was reached at age 18. Control of body weight by using total hip BMD as an index for intervention should be reasonable.

Short-term menatetrenone therapy increases gamma-carboxylation of osteocalcin with a moderate increase of bone turnover in postmenopausal osteoporosis: a randomized prospective study

The effect of vitamin K(2) (menatetrenone) on bone turnover was investigated in postmenopausal patients with osteoporosis. A 6-month open-label, randomized prospective study was conducted in 109 patients. The control group (n = 53) received calcium aspartate (133.8 mg of elemental calcium daily), while the menatetrenone group (n = 56) received 45 mg of menatetrenone daily for 6 months. Serum and urinary levels of bone turnover markers were monitored. The serum level of undercarboxylated osteocalcin (uc-OC) was significantly lower (P < 0.001) in the menatetrenone group than in the control group (at 1 month), while there was a higher level of osteocalcin containing gamma-carboxylated glutamic acid (Gla-OC) in the menatetrenone group than the control group (P = 0.018). Significant differences of uc-OC and Gla-OC between the two groups were observed from 1 month onward. In addition, a higher level of intact osteocalcin was found in the menatetrenone group compared with the control group after 6 months (P = 0.006). Assessment of bone resorption markers showed that menatetrenone therapy was associated with significantly higher urinary N-telopeptide of type I collagen (NTX) excretion compared with the control group after 6 months, while there was no significant difference of urinary deoxypyridinoline excretion between the two groups. In conclusion, one month of menatetrenone therapy enhanced the secretion and gamma-carboxylation of osteocalcin, while urinary NTX excretion was increased after 6 months of treatment. Further investigations are required to determine whether the effects of menatetrenone on bone turnover are associated with fracture prevention.

Nucleotide variations in genes encoding carbonic anhydrase 8 and 10 associated with femoral bone mineral density in Japanese female with osteoporosis

Osteoporosis is a multi-factorial common disease, which is caused by combination of genetic as well as environmental factors. Among several factors, osteoclast acidification pathways during bone resorption might play an important role. Carbonic anhydrases, consisting of a gene family, are essential for pH regulation by the osteoclast. Clinically, use of carbonic anhydrase inhibitors has been known to be associated with a bone-sparing effect as judged by spine bone mineral density (BMD). Here, we investigated single nucleotide polymorphisms (SNPs) in carbonic anhydrase genes that are expressed in bone tissues, i.e., CA8 and CA10, for possible association with femoral and lumbar BMD among 337 Japanese women with osteoporosis participated in BioBank Japan project. Significant correlation was observed between CA8 SNP, rs6984526, and femoral BMD (P = 0.00029); homozygous carriers of the major (C) allele (n = 166) had the highest BMD (0.754 +/- 0.006 g/cm(2), mean +/- SD), while heterozygous carriers (n = 135) were intermediate (0.741 +/- 0.07 g/cm(2)) and homozygous T-allele carriers (n = 31) had the lowest BMD (0.691 +/- 0.012 g/cm(2)). CA8 SNP as well displayed significant association with lumbar BMD in recessive model (P = 0.00017). In addition, CA10 SNP, rs2106329, also displayed strong association with femoral BMD (P = 0.00002). The results suggest that the variations of CA8 and CA10 loci may be important determinants of osteoporosis in Japanese women.

Effects of risedronate or alfacalcidol on bone mineral density, bone turnover, back pain, and fractures in Japanese men with primary osteoporosis: results of a two-year strict observational study

Although osteoporosis in men is already a major public health problem, there is still a dearth of data about the effects of risedronate in male osteoporosis, especially in Japanese with primary osteoporosis. Therefore, the objective of our study was to investigate the effects of risedronate on bone mineral density (BMD), bone turnover, back pain, and fractures in these patients prospectively for two years (at baseline, three months, six months, twelve months, and twenty-four months) both longitudinally and compared with those of alfacalcidol. The subjects enrolled for this study were 66 Japanese male patients with untreated primary osteoporosis (mean age 63.52 +/- 8.7 years), who were divided into two groups (44 with risedronate and 22 with alfacalcidol). We measured BMD by dual energy X-ray absorptiometry at three sites-the lumbar spine, femoral neck, and distal radius. Risedronate treatment significantly increased BMD at the lumbar spine and at the femoral neck, reduced bone-specific alkaline phosphatase (BAP) and serum N-terminal telopeptide of type I collagen (NTx), and reduced back pain, both longitudinally and compared with alfacalcidol treatment. We observed a lower rate of incident fracture in risedronate users. However, multiple logistic regression analysis revealed that this trend was not statistically significant, possibly because of the small number of patients enrolled. These potentially beneficial effects of risedronate on bone in male patients with primary osteoporosis suggest the possibility that osteoporosis should be treated with risedronate regardless of gender in order to effectively prevent subsequent osteoporotic fractures.

Prevalence of knee osteoarthritis, lumbar spondylosis, and osteoporosis in Japanese men and women: the research on osteoarthritis/osteoporosis against disability study

Musculoskeletal diseases, especially osteoarthritis (OA) and osteoporosis (OP), impair activities of daily life (ADL) and quality of life (QOL) in the elderly. Although preventive strategies for these diseases are urgently required in an aging society, epidemiological data on these diseases are scant. To clarify the prevalence of knee osteoarthritis (KOA), lumbar spondylosis (LS), and osteoporosis (OP) in Japan, and estimate the number of people with these diseases, we started a large-scale population-based cohort study entitled research on osteoarthritis/osteoporosis against disability (ROAD) in 2005. This study involved the collection of clinical information from three cohorts composed of participants located in urban, mountainous, and coastal areas. KOA and LS were radiographically defined as a grade of > or =2 by the Kellgren-Lawrence scale; OP was defined by the criteria of the Japanese Society for Bone and Mineral Research. The 3,040 participants in total were divided into six groups based on their age: < or =39, 40-49, 50-59, 60-69, 70-79, and > or =80 years. The prevalence of KOA in the age groups < or =39, 40-49, 50-59, 60-69, 70-79, and > or =80 years 0, 9.1, 24.3, 35.2, 48.2, and 51.6%, respectively, in men, and the prevalence in women of the same age groups was 3.2, 11.4, 30.3, 57.1, 71.9, and 80.7%, respectively. With respect to the age groups, the prevalence of LS was 14.3, 45.5, 72.9, 74.6, 85.3, and 90.1% in men, and 9.7, 28.6, 41.7, 55.4, 75.1, and 78.2% in women, respectively. Data of the prevalence of OP at the lumbar spine and femoral neck were also obtained. The estimated number of patients with KOA, LS, and L2-L4 and femoral neck OP in Japan was approximately 25, 38, 6.4, and 11 million, respectively. In summary, we estimated the prevalence of OA and OP, and the number of people affected with these diseases in Japan. The ROAD study will elucidate epidemiological evidence concerning determinants of bone and joint disease.

Randomized controlled study on the prevention of osteoporotic fractures (OF study): a phase IV clinical study of 15-mg menatetrenone capsules

An open-label study with blinded evaluation was performed to compare the preventive effect of a calcium supplement alone (monotherapy) or calcium supplement plus menatetrenone (combined therapy) on fracture in osteoporotic postmenopausal women aged 50 years or older. Patients were randomized to receive monotherapy (n = 2,193) or combined therapy (n = 2,185). Before randomization, the subjects were stratified into a subgroup without vertebral fractures (n = 2,986; no-fracture subgroup) and a subgroup with at least one vertebral fracture (n = 1,392; fracture subgroup). The incidence rate of new vertebral fractures during 36 months of treatment (primary endpoint) did not differ significantly between either subgroup of the two treatment groups. Although the cumulative 48-month incidence rate of new clinical fractures (secondary endpoint) was lower in the combined therapy group, the difference was not significant. There was a lower risk of new vertebral fractures in patients with at least five baseline fractures who received combined therapy. Also, the loss of height was less with combined therapy than with monotherapy among patients 75 years of age or older at enrollment, those whose last menstrual period occurred 30 years or more before enrollment, and those with at least five vertebral fractures at enrollment. Adverse events and adverse reactions were more frequent in the combined therapy group. In conclusion, menatetrenone therapy was not effective for preventing vertebral fractures in the full analysis set of this study, but the results suggested that it may prevent vertebral fractures in patients with more advanced osteoporosis.

Endocrinological analysis of 122 Japanese childhood cancer survivors in a single hospital

With recent improvements in the diagnosis and treatment of cancer, the number of childhood cancer survivors (CCSs) has been increasing in Japan. The importance of quality of life during the lifetime of CCSs has now been recognized, and the late effects of cancer treatments are essential and important issues. In this study we analyzed the endocrinological abnormalities of CCSs by retrospectively evaluating 122 outpatients (62 males and 60 females) who had been referred from pediatric oncologists to our follow-up clinic among 151 CCSs attending our hospital more than two years after their cancer treatment. Follow-up duration varied from 2 to 30 (median 8.0) years. Their average age was 17.3 (range 4-36, median 17.0) years, and 38 patients (31.1%) reached adulthood. Endocrinological abnormalities were found in 82 (67%) of 122 survivors. Gonadal dysfunction was observed in 60 patients (49%). Thirty-nine patients (32%) were short or grew at a slower rate. Twenty-six patients (21%) showed thyroid dysfunction. Other abnormalities were as follows: obesity in 20 patients (16%), leanness in 10 (8%), central diabetes insipidus in 11 (9%) and adrenocortical dysfunction in 9 (7%). Low bone mineral density was observed in 41 (42%) of 98 patients evaluated. These endocrinological abnormalities were caused by the combined effects of cancer itself and various treatments (chemotherapy, radiation therapy, surgery, and hematopoietic stem cell transplantation). Lifetime medical surveillance and continuous follow-up are necessary for CCSs, because treatment-related complications may occur during childhood and many years after the therapy as well. Endocrinologists should participate in long-term follow-up of these survivors in collaboration with pediatric oncologists.

Association of bone mineral density with deformity of the distal radius in low-energy Colles' fractures in Japanese women above 50 years of age

PURPOSE

To investigate whether the degree of radiographically observed pretreatment radius deformity of low-energy Colles' type distal radius fractures resulting from falls is associated with the degree of bone fragility as measured by bone mineral density (BMD) of the lumbar spine in Japanese women above 50 years of age.

METHODS

The study subjects were 125 consecutive Japanese women older than 50 years of age with Colles' type (AO type A and C) dorsally angulated distal radius fractures caused by falls. Fractures due to high-energy injuries such as traffic accidents were excluded. Radius deformity was assessed on anteroposterior and lateral radiographs by measuring ulnar variance, radial inclination, and dorsal angulation at initial examination before manual repositioning of the bone. Bone mineral density of the lumbar spine was also measured by dual energy x-ray absorptiometry at the follow-up visit.

RESULTS

There were significant differences in the respective values of ulnar variance, radial inclination, and dorsal angulation between patients with BMD values < 70% of the mean value of young adults and those with BMD values > or = 70%. Radius deformity was significantly greater for all parameters in the former group relative to the latter. The respective values of increased ulnar variance, decreased radial inclination, and increased dorsal angulation significantly correlated with lower BMD. Stepwise regression analysis of data of all subjects identified that ulnar variance was significantly associated with dorsal angulation, BMD, and radial inclination. The addition of body height, body weight, body mass index, and urinary type I collagen cross-linked N-telopeptides (bone resorption marker) to the regression analysis of data of a subset of patients confirmed that ulnar variance was significantly associated with BMD and radial inclination.

CONCLUSIONS

There is a significant association between BMD of the lumbar spine and radiographic radius deformity seen in low-energy Colles' type distal radius fractures resulting from falls in Japanese women above 50 years of age.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic I.

Co-occurrence of subchondral insufficiency fracture of the femoral head and contralateral femoral neck fracture in a rheumatic patient receiving steroid treatment

We describe a 79-year-old woman with rheumatoid arthritis who suffered from subchondral insufficiency fracture of the femoral head (SIF) and contralateral femoral neck fracture. Radiographs obtained two months after the onset of thigh pain showed collapse of the right femoral head and contralateral femoral neck fracture. MRI revealed a subchondral serpiginous low-intensity band in the right femoral head on the T2-weighted image. This case report suggests that SIF should be considered in the differential diagnoses of rheumatic patients who suffer from thigh pain without antecedent trauma.

Secondary osteoporosis in long-term bedridden patients with cerebral palsy

BACKGROUND

The aim of the present paper was to investigate 20 pediatric patients with cerebral palsy and secondary osteoporosis and consider the efficacy, influence and index of treatment.

METHODS

A total of 10 boys and 10 girls, age 1-16 years (mean 7.6 years) with secondary osteoporosis and cerebral palsy treated for 6 months, were studied. Bone mineral density (BMD) was measured. The bone turnover markers were measured just before and 4 months after treatment or at the time of early discontinuation of treatment. The treatment was classified into two groups: vitamin D (alfacarcidol) only; and with bisphosphonate (risedronate).

RESULTS

Monotherapy with alfacarcidol was effective for secondary osteoporosis in children, but when used in combination with risedronate it was even more effective in improving BMD. In the two groups, bone-specific alkaline phosphate (BAP) decreased from pretreatment to post-treatment assessment in all but one case, but there was no significant correlation in the difference in DeltaBAP with DeltaBMD. DeltaBAP assumed changes in BAP in treatment either before or after, and DeltaBMD also assumed changes in BMD. N-telopeptides of type I collagen (NTX)/Cr decreased in all cases. The correlation of DeltaNTX/Cr with DeltaBMD was not significant. The therapy and its efficacy did not correlate to the patients' age, sex, medicine regimen or enteral nutrition.

CONCLUSIONS

Risedronate therapy is effective for patients presenting with secondary osteoporosis with cerebral palsy. Moreover, it is desirable to treat patients more aggressively from the early stage because risedronate is not affected by the patients' other factors.

Association of genetic variations of genes encoding thrombospondin, type 1, domain-containing 4 and 7A with low bone mineral density in Japanese women with osteoporosis

Twins and family studies have shown that genetic factors are important determinants of bone mass. Important aspects of bone mineral density (BMD) regulation are endocrine systems, notably hormonal regulation of adrenal corticoids, as indicated by clinical knowledge of glucocorticoid-induced osteoporosis. Glucocorticoid is known to negatively regulate bone mass in vivo, and glucocorticoid increases thrombospondin messenger ribonucleic acid (mRNA) levels. We studied single nucleotide polymorphisms (SNPs) in genes encoding thrombospondin, type 1, domain-containing 4 and 7A (THSD4 and THSD7A) for possible association with lumbar and femoral BMD among 337 Japanese women with osteoporosis who participated in the BioBank Japan project. Genetic variations of THSD4 and THSD7A loci displayed significant association with lumbar and femoral BMD. Most significant correlation was observed for THSD7A SNP rs12673692 with lumbar BMD (P = 0.00017). Homozygous carriers of the major (G) allele had the highest BMD [0.886 +/- 0.011 g/cm2, mean +/- standard deviation (SD)], whereas heterozygous carriers were intermediate (0.872 +/- 0.013 g/cm2) and homozygous A-allele carriers had the lowest (0.753 +/- 0.023 g/cm2). THSD4 SNP rs10851839 also displayed strong association with lumbar BMD (P = 0.0092). In addition, both THSD7A and THSD4 displayed significant association with femoral BMD in a recessive model (P = 0.036 and P = 0.0046, respectively). Results suggest that variations of THSD7A and THSD4 loci may be important determinants of osteoporosis in Japanese women.

Development and application of a Japanese model of the WHO fracture risk assessment tool (FRAX)

The present study estimated the 10-year probability using the Japanese version of WHO fracture risk assessment tool (FRAX) in order to determine fracture probabilities that correspond to intervention thresholds currently used in Japan and to resolve some issues for its use in Japan.

INTRODUCTION

The objective of the present study was to evaluate a Japanese version of the WHO fracture risk assessment (FRAX) tool to compute 10-year probabilities of osteoporotic fracture in Japanese men and women. Since lumbar spine bone mineral density (BMD) is used preferentially as a site for assessment, and densitometers use Japanese reference data, a second aim was to investigate the suitability and impact of this practice in Japan.

METHODS

Fracture probabilities were computed from published data on the fracture and death hazards in Japan. Probabilities took account of age, sex, the presence of clinical risk factors and femoral neck BMD. Fracture probabilities were determined that were equivalent to intervention thresholds currently used in Japan. The difference between T-scores derived from international reference data and that using Japanese-specific normal ranges was estimated from published sources. The gradient of risk of BMD for fracture in Japan was compared to that for BMD at the lumbar spine in the Hiroshima cohort.

RESULTS

The 10-year probabilities of a major osteoporosis-related fracture that corresponded to current intervention thresholds ranged from approximately 5% at the age of 50 years to more than 20% at the age of 80 years. The use of femoral neck BMD predicts fracture as well as or better than BMD tests at the lumbar spine. There were small differences in T-scores between those used for the model and those derived from a Japanese reference population.

CONCLUSIONS

The FRAX mark tool has been used to determine possible thresholds for therapeutic intervention, based on equivalence of risk with current guidelines. The approach will need to be supported by appropriate health economic analyses. Femoral neck BMD is suitable for the prediction of fracture risk among Japanese. However, when applying the FRAX model to Japan, T-scores and Z-scores should be converted to those derived from the international reference.

Efficacy of combined treatment with raloxifene and alfacalcidol on bone density and biochemical markers of bone turnover in postmenopausal osteoporosis

Because both raloxifene (RLX) and alfacalcidol (ALF) have been established as therapeutic agents for osteoporosis, it is tempting to speculate that the combination therapy of RLX and ALF might provide benefits over that of either one alone. However, the efficacy of the combination therapy has not been reported yet. The purpose of this study was thus to assess the efficacy of the combination therapy on bone mineral density (BMD) and bone turnover in patients with postmenopausal osteoporosis. Sixty postmenopausal patients (mean age 71.62 +/- 9.9 years) with untreated osteoporosis were selected for this study, and were randomly divided into two groups by therapeutic regimen. Group A consisted of 28 patients treated with RLX plus ALF, while Group B consisted of 32 patients with RLX alone. Among them, 20 in group A and 22 in group B completed this study. Contrary to our expectations, at either 6 months or 12 months after the initiation of treatment, RLX plus ALF did not increase BMD at any of the skeletal sites measured, including lumbar spine, femur, and radius, nor did it reduce bone-specific alkaline phosphatase or N-terminal telopeptide of type I collagen more than RLX alone. Our results do not support the hypothesis that the combination therapy of RLX and ALF exerts more beneficial effects on bone compared than with RLX alone. However, it still remains unclear from this study whether the combination therapy of RLX and ALF is more efficacious in preventing fractures compared with RLX alone. Further studies are needed to clarify these issues.

Association between baseline values of bone turnover markers and bone mineral density and their response to raloxifene treatment in Japanese postmenopausal women with osteoporosis

It has been well established that raloxifene improves bone turnover, increases bone mineral density (BMD), and reduces the risk of fractures. However, it remains obscure which patients are more likely to respond to treatment with raloxifene in patients with postmenopausal osteoporosis. The purpose of this study was to investigate associations between baseline values of BMD and bone turnover markers (BTMs) and changes of those values after 1-year treatment with raloxifene. Sixty-eight Japanese postmenopausal women with untreated osteoporosis were selected for this study, among whom 58 patients (mean age 70.40 +/- 9.2 years) completed this study. Lower baseline values of BMD at the lumbar spine, the femoral neck, and the distal radius were significantly correlated with greater increases of BMD at those corresponding sites after 1-year treatment with raloxifene. On the other hand, higher baseline values of bone-specific alkaline phosphatase (BAP) and serum N-terminal telopeptide of type I collagen (NTx) were significantly correlated with greater reductions of BAP and NTx, respectively, after 1-year treatment with raloxifene. Although longer and larger studies with fracture endpoints are needed, our findings suggest that baseline values of BMD and BTMs can be used to predict subsequent skeletal response to raloxifene therapy in Japanese postmenopausal women with osteoporosis.

Comparison of effects of alendronate and raloxifene on lumbar bone mineral density, bone turnover, and lipid metabolism in elderly women with osteoporosis

PURPOSE

To compare the effects of alendronate and raloxifene on lumbar bone mineral density (BMD), bone turnover, and lipid metabolism in elderly women with osteoporosis.

SUBJECTS AND METHODS

One hundred twenty-two postmenopausal women with osteoporosis (mean age: 69.4 years) were randomly divided into 2 groups of 61 patients: the alendronate group and the raloxifene group. BMD of the lumbar spine, urinary level of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of alkaline phosphatase (ALP), total cholesterol (TC), high and low density lipoprotein cholesterols (LDL-C and HDL-C, respectively), and triglycerides (TG) were measured during the 12-month-treatment period.

RESULTS

The trial in 50 patients in the alendronate group and 52 patients in the raloxifene group could be completed. Both alendronate and raloxifene increased lumbar BMD (+8.0% and +2.4% at 12 months, respectively), followed by reductions of urinary NTX level and serum ALP level; however, the effects of alendronate were more pronounced than those of raloxifene. Only raloxifene reduced the serum levels of TC and LDL-C (-3.9% and -7.7% at 12 months, respectively), without any significant effect on the serum HDL-C and TG levels.

CONCLUSION

The present study confirmed the efficacy of alendronate greater than raloxifene in increasing lumbar BMD through its effect on marked reduction of the bone turnover more than by raloxifene, and some beneficial effects of raloxifene on lipid metabolism in elderly women with osteoporosis.

Raloxifene-induced acceleration of platelet aggregation

A 59-year-old postmenopausal woman diagnosed to have primary osteoporosis began to take 60 mg daily of oral raloxifene. The platelet aggregation induced by 1 microM adenosine diphosphate (ADP) and the alpha2-antiplasmin activity were accelerated significantly after 8 weeks from the beginning of raloxifene-treatment, and gradually deteriorated up to 24 weeks. ADP markedly caused the phosphorylation of Akt in the platelets obtained at 24 weeks. Although there were no subjective complaints at 24 weeks, the medication was stopped with her consent to avoid any adverse effects due to thrombus formation. The platelet hyper-aggregability and Akt phosphorylation induced by ADP disappeared at 4 weeks after the cessation of medication. These results strongly suggest that raloxifene caused the acceleration of platelet aggregation and subclinical thrombus formation through the Akt signal pathway in this case.

The synergistic effect of bone mineral density and methylenetetrahydrofolate reductase (MTHFR) polymorphism (C677T) on fractures

A functional polymorphism in methylenetetrahydrofolate reductase (MTHFR) has been identified at codon 677 (C677T). The T-allele variant (valine type) has lower enzyme activity than the wild type (C-allele or alanine type), resulting in a slightly elevated homocysteine level, which has been recently recognized as a risk factor for fracture. However, whether subjects bearing the T allele have higher susceptibility to fractures is still controversial. We have investigated the effects of MTHFR polymorphism on fracture susceptibility in Japanese postmenopausal women. A total of 502 postmenopausal ambulatory Japanese women were followed up for 5.1 +/- 3.4 (mean +/- SD) years, and a total of 155 patients with incident fractures (121 patients with vertebral fractures and 34 cases with fractures at other sites) were recorded. When compared with the patients without any fractures, the patients with incident fractures were older, had more prevalent fractures, had higher urinary levels of bone turnover markers as well as plasma homocysteine level, but were shorter in body height and had lower bone mineral density. The prevalence of the TT genotype of MTHFR was significantly higher in the patients with incident fractures compared to the other genotypes. The subjects with the TT genotype had a higher incidence rate of fracture and higher plasma level of homocysteine than the subjects bearing the non-TT genotype. This relationship was observed in both osteoporotic and nonosteoporotic groups. The hazard ratio for TT genotype without osteoporosis, non-TT genotype with osteoporosis, and TT genotype with osteoporosis was 1.49 (0.91-2.45), 3.64 (2.50-5.29), and 7.21 (4.34-11.97), respectively, compared to the non-TT genotype without osteoporosis. A higher hazard ratio for the TT genotype with osteoporosis was still apparent after adjustment for age, body size, and number of prevalent vertebral fractures. These results indicate that the TT genotype of MTHFR may be a risk factor for future fracture in addition to the traditional risk factors.

Three-month changes in bone turnover markers and bone mineral density response to raloxifene in Japanese postmenopausal women with osteoporosis

It has been well established that raloxifene (RLX) improves bone turnover, increases bone mineral density (BMD), and reduces the risk of fractures. However, it remains obscure how to monitor the therapeutic effects of RLX, while numerous clinical trials for other antiresorptive agents have suggested that greater short-term reductions of bone turnover markers (BTMs) can predict greater increases in BMD and greater reduction in risk of future fractures. The purpose of this study was to investigate associations between short-term reductions of BTMs and subsequent changes of BMD after 1-year treatment with RLX. Seventy-three Japanese postmenopausal women with untreated osteoporosis were selected for this study. Reductions in BTMs [bone-specific alkaline phosphatase (BAP) or serum N-terminal telopeptide of type I collagen (NTx)] after 3 months did not correlate with increases of BMD at any major sites (lumbar spine, femoral neck, total neck, and distal 1/3 radius) either after 6 months or after 12 months. Our results suggest that short-term reductions or 3-month reductions of BTMs with RLX treatment cannot be used to predict increases of BMD. However, this does not directly mean that short-term reductions or 3-month reductions of BTMs with RLX treatment cannot be used to predict risk reduction of future fractures or the ultimate effects of RLX on bone. Further studies with fracture endpoints in longer observation and larger number of patients are warranted to establish how to monitor the therapeutic effects of RLX or early identification of responders or nonresponders to RLX treatment.

Establishment of BMD reference databases for the diagnosis and evaluation of osteoporosis in central southern Chinese men

Osteoporosis in men is an increasingly important public health problem. This study was designed to establish bone mineral density (BMD) reference databases for central southern Chinese men at multiple skeletal sites. We recruited 2433 native Chinese males for BMD assessment. Of these, 1537 were healthy volunteers (age range, 15-85 years), and 896 were suspected to have osteoporosis. BMD values were measured at the posteroanterior (PA) and lateral spine, hip, and distal forearm using a Delphi A absorptiometer. The quadratic regression model provided the best fit for age-related changes in BMD in the spine and hip. The cubic regression model was the best for describing age-related BMD changes in the distal forearm. Peak BMD in the lumbar spine, femoral neck, and total hip occurred at 15-19 years. Peak BMD at the distal forearm occurred at 40-44 years. The prevalence of primary osteoporosis in subjects ranging from 50-85 years was 4.3%-27.7% at various skeletal sites. Compared to the databases established here, the Hologic databases led to significantly higher osteoporosis detection rates. The BMD reference databases established for central southern Chinese men provide the most reliable diagnostic standards for osteoporosis detection in men of central south China.

Efficacy of risedronate in Japanese male patients with primary osteoporosis

OBJECTIVE

Although osteoporosis in men previously was relatively neglected, bisphosphonates have been strongly suggested as potent therapeutic agents. However, there are few studies on the effects of risedronate in male osteoporosis, especially in Japanese with primary osteoporosis. The aim of our study was to prospectively evaluate the effects of risedronate on bone mineral density (BMD) and bone turnover in Japanese male patients.

METHODS

According to the therapeutic regimen, the subjects were divided into two groups (group A, 22 with risedronate; group B, 10 without risedronate). During a one-year study duration, we measured bone-specific alkaline phosphatase (BAP) and serum N-terminal telopeptide of type I collagen (NTx) every 3 months, and BMD at 7 sites by dual-energy X-ray absorptiometry every 6 months.

PATIENTS

The subjects were 32 Japanese male patients with untreated primary osteoporosis.

RESULTS

In group A, but not in group B, BMD was significantly increased at the lumbar spine both at 6 months and 12 months, and at the femoral neck at 12 months, compared with baseline. Likewise, in group A, but not in group B, both BAP and NTx were significantly decreased at all time points measured (3 months, 6 months, and 12 months), compared with baseline.

CONCLUSION

These results confirmed the beneficial effects of risedronate upon increasing BMD and reducing bone turnover markers in Japanese male patients with primary osteoporosis, comparable to those previously reported in postmenopausal patients with osteoporosis.

Effects of the sample size of reference population on determining BMD reference curve and peak BMD and diagnosing osteoporosis

Establishing reference databases generally requires a large sample size to achieve reliable results. Our study revealed that the varying sample size from hundreds to thousands of individuals has no decisive effect on the bone mineral density (BMD) reference curve, peak BMD, and diagnosing osteoporosis. It provides a reference point for determining the sample size while establishing local BMD reference databases.

INTRODUCTION

This study attempts to determine a suitable sample size for establishing bone mineral density (BMD) reference databases in a local laboratory.

METHODS

The total reference population consisted of 3,662 Chinese females aged 6-85 years. BMDs were measured with a dual-energy X-ray absorptiometry densitometer. The subjects were randomly divided into four different sample groups, that is, total number (Tn) = 3,662, 1/2n = 1,831, 1/4n = 916, and 1/8n = 458. We used the best regression model to determine BMD reference curve and peak BMD.

RESULTS

There was no significant difference in the full curves between the four sample groups at each skeletal site, although some discrepancy at the end of the curves was observed at the spine. Peak BMDs were very similar in the four sample groups. According to the Chinese diagnostic criteria (BMD >25% below the peak BMD as osteoporosis), no difference was observed in the osteoporosis detection rate using the reference values determined by the four different sample groups.

CONCLUSIONS

Varying the sample size from hundreds to thousands has no decisive effect on establishing BMD reference curve and determining peak BMD. It should be practical for determining the reference population while establishing local BMD databases.

The cost-effectiveness of risedronate treatment in Japanese women with osteoporosis

We constructed a mathematical model for assessing the cost-effectiveness of providing BMD (bone mineral density) scans to Japanese women aged 55 years and over and treating, with risedronate, those that are shown to be osteoporotic. Fracture rates, cost data, utility values, and the increased risks of fractures associated with T-score and vertebral fracture history were taken from published literature. We estimated the cost of fractures avoided due to risedronate treatment, allowing the net changes in cost, incorporating both intervention and fracture costs to be calculated. The QALYs (quality adjusted life years) gained through treatment were calculated enabling cost per QALY ratios to be presented. Further analyses were undertaken assuming treatment was reserved for older women and/or those who had sustained a vertebral fracture in the previous 2 years. Cost per QALY values were inversely related to absolute risk of fracture. Assuming a cost per QALY value threshold of US dollars 100,000, we concluded that providing BMD scans to women aged 70 years and over who had sustained a vertebral fracture in the previous 2 years and treating those that were osteoporotic was cost-effective. However, providing BMD scans for women without a vertebral fracture in the previous 2 years was not cost-effective, even in women aged 85 years and older.

Nonenzymatic collagen cross-links induced by glycoxidation (pentosidine) predicts vertebral fractures

Advanced glycation end products (AGE) in collagen have been reported to decrease the mechanical property of bone. However, there are no available data on the relation between fracture risk and levels of glycoxidative (nonenzymatic) cross-links of collagen in clinical samples. A total of 432 Japanese elderly women who were not receiving any drug treatment for osteoporosis were selected and followed for 5.2 +/- 3.3 (mean +/- SD) years for this observational study. Vertebral fractures and bone mineral density were assessed at baseline and then at 1- to 2-year intervals or at indication of any symptom. Two types of collagen metabolites were measured at baseline: urinary N-terminal telopeptide of type I collagen (NTX), a marker of pyridinium cross-link, and urinary pentosidine, a nonenzymatic collagen cross-link produced by AGEs. A total of 97 incident vertebral fractures on 72 subjects were observed. Simple regression analysis using Cox's hazards model showed that log-transformed urinary NTX and pentosidine are significant risk factors for time-dependent incidence of vertebral fractures, in addition to the traditional risk factors (age, lumbar bone mineral density, and number of prevalent vertebral fractures). However, urinary excretion of pentosidine (hazard ratio, 1.33; 95% CI, 1.01-1.76, P = 0.04) was a significant predictor of incident vertebral fracture after adjustment for other traditional risk factors. The present data suggest that AGE-related collagen cross-link is a novel risk for vertebral fracture.

A comparative study of clinical and radiological outcomes of dorsally angulated, unstable distal radius fractures in elderly patients: intrafocal pinning versus volar locking plating

PURPOSE

To compare the clinical and radiological outcomes of intrafocal pinning (IFP) and volar locking plating (VLP) of dorsally angulated, unstable distal radius fractures in elderly patients.

METHODS

The subjects were 62 consecutive patients over 60 years of age with dorsally angulated, unstable distal radius fractures treated with IFP or VLP. Bone mineral density (BMD) of the lumbar spine was measured by dual-energy x-ray absorptiometry at first examination. The range of motion and grip strength were measured at follow-up examinations, and ulnar variance (UV) was measured on radiographs at baseline and follow-up postoperative examinations.

RESULTS

There were no notable differences in gender, age, follow-up period, baseline UV, BMD, and AO classification between IFP and VLP groups. There was no difference between the UV in VLP immediately after surgery and at the final follow-up examination; however, IFP showed a significant loss of reduction as measured by UV. In patients with UV more than 5 mm or BMD less than 70% of young adult mean (YAM) at first examination, UV increased again at the final follow-up examination in IFP, while surgically corrected UV was maintained in VLP, independent of the degree of baseline UV and BMD. VLP resulted in earlier recovery of postoperative range of motion and grip strength compared with IFP. The range of flexion and the grip strength value were significantly larger in VLP at final examination.

CONCLUSIONS

VLP, but not IFP, can maintain surgically corrected UV in distal radius fractures, independent of the degrees of initial UV and BMD. VLP enhances earlier recovery in range of motion and grip strength than IFP.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Use of Fuzzy Neural Network in Diagnosing Postmenopausal Women with Osteoporosis Based on Dental Panoramic Radiographs

A thin or eroded cortex of the mandible detected on dental panoramic radiographs is independently associated with low skeletal bone mineral density (BMD) or osteoporosis in postmenopausal women. The purposes of this study were to develop new computer-aided diagnosis system that combines these two panoramic measures by using fuzzy neural networks (FNN) for identifying postmenopausal women with osteoporosis. Dental panoramic radiographs of 100 postmenopausal women who visited our clinic and had BMD assessments at the lumbar spine and the femoral neck were used in this study. Mandibular cortical width and shape were measured by computer-aided systems and used as the inputs. This system partitioned the input space into a set of subspaces using a novel fuzzy thresholding and constructed the fuzzy inference system incorporated with multi layer perceptron neural network. Our results show that the combination of cortical width and shape by using FNN can be used for the identification of postmenopausal women with osteoporosis in dental clinic. Dentists may identify postmenopausal women accurately by using the new FNN based system and refer them to medical professional for BMD testing.

Assessment of mandibular buccal and lingual cortical bones in postmenopausal women

OBJECTIVE

Correlations between the widths of mandibular cortical bones and the bone mineral density (BMD) of the spine were analyzed to evaluate the influence of the general bone condition.

STUDY DESIGN

Thirty postmenopausal women were enrolled in this investigation. The widths of cortical bones in sites of the mental foramen and the BMD of the mandibular cancellous bone were measured using multislice computerized tomography (CT) images. The BMD of the lumbar spine was measured using dual-energy x-ray absorptiometry, and the ratio to the young adult mean (YAM) was obtained.

RESULTS

A weak correlation between the widths of cortical bones and the ratio to the YAM was observed. Also, correlations between the widths of cortical bones and the BMD of the mandible were noted.

CONCLUSION

The widths of buccal and lingual cortical bones in the mesial and distal sites of the mental foramen measured on axial CT images do not serve as a reliable examination for the BMD of the lumbar spine.

Comparisons of bone mass measurements on various skeletal sites including quantitative ultrasonography of the calcaneus for assessing age-related losses, their correlations, and diagnostic agreement using the Japanese and WHO criteria for osteoporosis

PURPOSE

The aim of this study was to compare age-related bone losses and correlations among several bone mass measurements and to evaluate diagnostic agreement among them using the Japanese and WHO criteria for osteoporosis.

MATERIALS AND METHODS

A total of 846 women (mean +/- SD: age 54 +/- 9 years) were evaluated. Bone mineral densities of the lumbar spine, femoral neck, and calcaneus were measured by dual X-ray absorptiometry and distal radius by peripheral computed tomography. Quantitative ultrasonography (QUS) parameters of the calcaneus were also measured. The age-related bone losses after 50 years of age and correlations among bone mass results were evaluated using linear regression analysis. Diagnostic agreement was evaluated by kappa statistics.

RESULTS

The annual losses ranged from 1.0% to 1.6%. The correlation coefficients ranged from 0.54 to 0.78. The kappa scores ranged from 0.52 to 0.30 for all subjects using the Japanese criteria and from 0.38 to 0.15 using the WHO criteria.

CONCLUSION

Bone mass measurements including QUS on various skeletal sites documented age-related changes similarly, and their bone masses correlated moderately. The diagnostic agreements among them were fair to poor. To screen out women with a risk of osteoporosis, it is important to choose which technique to use and which skeletal site to measure.

Association of KIT gene polymorphisms with bone mineral density in postmenopausal Korean women

Bone mineral density (BMD) is a major factor for determining bone strength and osteoporotic fracture risk, and is determined by environmental and multiple genetic factors. KIT, which encodes a transmembrane receptor with tyrosine kinase activity, plays an important role in the differentiation of osteoclasts. We examined the associations between KIT gene polymorphisms and BMD in postmenopausal Korean women. All exons, their boundaries, and the promoter region (approximately 1.5 kb) from 24 individuals were directly sequenced. Eighteen polymorphisms were identified, and three single-nucleotide polymorphisms (SNPs) were genotyped in all study participants (n=946). BMD at the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry. The mean age of the study subjects was 58.9+/-7.5 years, and the mean number of years since menopause was 9.6+/-7.9 years. None of the three SNPs (-1694G>T, +41894A>G, and +49512G>A) was significantly associated with BMD value. However, multivariate analysis showed that the ht3 (-1694T-+41894A-+49512G) was significantly associated with lower BMD at the femoral neck (P=0.007 in the recessive model). These findings indicate that KIT-ht3 may be a useful genetic marker for osteoporosis and that KIT may have a role on bone metabolism in humans.

Association of a single-nucleotide variation (A1330V) in the low-density lipoprotein receptor-related protein 5 gene (LRP5) with bone mineral density in adult Japanese women

Low-density lipoprotein receptor-related protein 5 (LRP5), a co-receptor of Wnt signaling, is an important regulator of bone development and maintenance. Recently we identified correlation between an intronic single-nucleotide polymorphism (SNP) in the LRP5 gene and vertebral bone mineral density (BMD), indicating that a genetic ground exists at this locus for determination of BMD. In the study reported here, we searched for nucleotide variation(s) that might confer susceptibility to osteoporosis among an extended panel of 387 healthy subjects recruited from the same hospital (Group-A), as well as among 384 subjects from the general population in eastern Japan (Group-B). We basically focused on two potentially functional variations, Q89R (c.266A > G) and A1330V (c.3989C > T), whose functional effects by the amino-acid changes were estimated by the SIFT software program; it predicted the 1330 V allele as deleterious ("intolerant") although the minor allele of Q89R was questionable. By analyzing associations between the variant alleles and the BMD, reproducible association of the minor variant of A1330V to lower adjusted BMD levels was detected; i.e., In Group-A subjects 1330-V significantly associated with the spinal BMD Z-score (P = 0.034), and in Group-B it associated with low radial BMD (P = 0.019). From haplotype and linkage disequilibrium (LD) analysis for 29 SNPs, we detected two separate LD blocks within the entire 137-kb LRP5 locus, basically consistent with a previous report on Caucasians. One of the second block haplotype significantly associated with adjusted BMD (r = 0.15, P = 0.004). Possible combined effect of Q89R and A1330V belonging to different LD blocks was denied by multiple regression analyses. Our results indicate that genetic variations in LRP5 are important factors affecting BMD in adult women and that 1330 V may contribute to osteoporosis susceptibility, at least in Japanese.