Transforming Growth Factor-β1 Gene Polymorphisms and Bone Turnover,Bone Mineral Density and Fracture Risk in Southern Chinese Women

Genetic contributions play an important role in determining bone mineral density (BMD) and bone turnover. Transforming growth factor- (TGF-) is abundant in bone and has been implicated as an important regulator of both bone formation and resorption. Several polymorphisms of the TGF-1 gene have recently been suggested to be associated with BMD and susceptibility to osteoporotic spine fractures. To determine the relationship between TGF-1 polymorphisms and BMD in southern Chinese women, three SNPs at C^–1348-T, T²⁹-C, and T^861-20-C of TGF-1 gene were analyzed in 237 postmenopausal southern Chinese women by RFLP and direct sequencing. BMD at the lumbar spine and hip region, biochemical markers of bone turnover, as well as serum levels of TGF-1 were measured. Only the T²⁹-C polymorphism of TGF-1 gene was associated with BMD and fracture risk. The prevalence of fragility fractures was significantly higher in individuals with TC genotype (P < 0.05). Serum alkaline phosphatase and osteocalcin levels as well as urinary N-telopeptide excretion were significantly higher in women with TC than with TT or CC genotypes, and the difference remained significant after adjusting for age and BMI (all P < 0.05). Women with TC genotype had lower BMD at the trochanteric (P < 0.03) and total hip region (P = 0.05). No difference was observed in the serum TGF-1 levels among the three genotypes. In conclusion, an association between T²⁹-C polymorphisms of TGF-1 gene and BMD, bone turnover as well as fragility fractures were demonstrated in postmenopausal southern Chinese women.     

Oral daily ibandronate prevents bone loss in early postmenopausal women without osteoporosis.

Oral daily ibandronate was investigated for the prevention of bone loss in postmenopausal women without osteoporosis (n = 653). BMD at the lumbar spine and hip were significantly increased (3.1% and 1.8%, respectively; p < or = 0.0001 versus placebo) with 2.5 mg ibandronate after 24 months. Oral ibandronate is a promising option for the prevention of postmenopausal bone loss. INTRODUCTION: Further strategies to manage patients most at risk from developing postmenopausal osteoporosis are required. The objectives of this multicenter, double-blind, randomized, placebo-controlled study were to examine the efficacy, tolerability, and optimal dose of oral daily ibandronate in the prevention of bone loss in postmenopausal women. MATERIALS AND METHODS: In total, 653 women (mean bone mineral density [BMD] T-score > -2.5 at the lumbar spine), who had been postmenopausal for at least 1 year, were allocated to one of four strata based on time since menopause and baseline lumbar spine BMD. Women were randomized to receive calcium (500 mg daily) plus either placebo (n = 162) or ibandronate 0.5 mg (n = 162), 1 mg (n = 166), or 2.5 mg (n = 163) as once-daily oral treatment for 2 years. The primary endpoint was the mean percent change in lumbar spine BMD with ibandronate versus placebo. RESULTS AND CONCLUSIONS: After 2 years, oral daily ibandronate produced a dose-related and sustained maintenance or increase in BMD at the lumbar spine and hip (total hip, femoral neck, trochanter), together with a dose-related reduction in the rate of bone turnover. The greatest nominal increases in spinal and hip BMD were observed with the 2.5-mg dose, which produced statistically significant BMD gains compared with placebo at 6 months and all subsequent time-points at the spine and hip (3.1% and 1.8% increase in lumbar spine and total hip BMD, respectively, versus placebo; p < or = 0.0001 after 24 months). Oral daily ibandronate was well tolerated with an incidence of upper gastrointestinal adverse events similar to placebo. No safety concerns were identified. In summary, oral daily ibandronate 2.5 mg decreases bone turnover, preserves or increases BMD in the spine and proximal femur, and is well tolerated. Oral ibandronate provides a promising option for the prevention of bone loss in postmenopausal women.     

Tests of linkage and/or association of TGF-β1 and COL1A1 genes with bone mass

Transforming growth factor beta 1 (TGF-1) is involved in bone metabolism and collagen type I alpha 1 (COL1A1) is the most abundant protein of bone matrix. Both have been considered as candidate genes for osteoporosis. In this study, we employed the transmission disequilibrium test (TDT) to examine the relationship between each of the two genes with bone mineral density (BMD) and bone mineral content (BMC) at the spine and hip in a sample of 1668 subjects from 387 Caucasian nuclear families. For the TGF-1 gene, three SNPs, SNP1, SNP2, and SNP4 (located in exon 1, intron 4 and intron 5, respectively) were tested and the minor allele frequencies were 30.9%, 2.1% and 27.0%, respectively. All eight possible haplotypes (TGF1–8) were observed. For the COL1A1 gene, the minor allele frequencies of SNP5, SNP6 and SNP8 (located in exon 1, intron 1, and exon 45, respectively) were 15.2%, 18.7%, 2.0%, respectively, and only six of eight potential haplotypes (COL1–6) were obtained. In the whole sample, total associations were observed between haplotype COL5 with spine BMD (P=0.027), haplotypes COL3 and TGF4 with hip BMC (P=0.002, 0.003, respectively). Within-family associations were found for spine BMD at haplotypes TGF4 (P=0.027) in female offspring families and TGF3 (P=0.021) in male offspring families. Further studies with denser markers and larger sample size are required to eventually define the relationship between these two genes with bone mass at the spine and hip.     

Risk of fracture among women who lose bone density during treatment with alendronate. The Fracture Intervention Trial

It is commonly believed that the response to treatment in patients on alendronate is proportional to the increase in bone mineral density (BMD), and that those who lose BMD during treatment might not respond to treatment. In the Fracture Intervention Trial 6,459 women were randomly assigned to treatment with alendronate or placebo; BMD was measured annually, and new spine fractures were assessed by lateral spine films, taken at baseline and end of follow-up. Among subjects who took at least 70% of the study drug (5,220 women), we compared reductions in risk of spine fractures at end of follow-up (3 or 4 years) within various levels of change in total hip and spine BMD after 1 and 2 years of treatment, after adjustment for differences in characteristics between the treatment and control groups. Women losing BMD at the lumbar spine (0% to 4%) while on alendronate had a reduction of 60% in vertebral fracture risk [OR=0.40 (0.16, 0.99)] compared to their counterparts in the placebo group. The few women that lost more than 4% did not have a significant benefit [OR=0.15 (0.02, 1.29)]. Those who gained BMD (0% to 4%) during treatment had a reduction in risk of 51% [OR=0.49 (0.30, 0.78)]. Similarly, women who lost total hip BMD (0% to 4%) during the first year on alendronate had a 53% decreased risk of vertebral fracture compared to their controls taking placebo [OR=0.47 (0.27, 0.81)], whereas those gaining BMD (0% to 4%) had a comparable risk reduction [OR=0.49 (0.34, 0.71)]. This was not observed for the few women who lost more than 4% [OR=0.61 (0.11, 3.45)]. Patients who lost BMD at both the hip and spine were not protected by alendronate. Among patients who adhere to treatment with alendronate, even those who lose BMD benefit from a substantial reduction in risk of vertebral fracture. So, the reduction in bone turnover induced by alendronate might be more important than BMD changes. The few women who lose the most BMD (more than 4% per year) might not benefit from the treatment.This paper was written for the Fracture Intervention Trial Research GroupPresented in part at the 22nd Annual Meeting of the American Society for Bone and Mineral Research, Toronto, Canada, 2000     

Significance of serum CrossLaps as a predictor of changes in bone mineral density during estrogen replacement therapy; comparison with serum carboxyterminal telopeptide of type I collagen and urinary deoxypyridinoline

The newly developed Elecsys -CrossLaps/serum assay measures C-terminal telopeptide of type I collagen and has thus been proposed as a reliable serum marker for bone resorption. We investigated its usefulness for monitoring the therapeutic effect of estrogen replacement therapy on bone turnover and bone mineral density (BMD) in patients with postmenopausal osteoporosis. Serum -CTx decreased by 43.2% ± 9.2% (mean ± SD), and 55.1% ± 7.0% at 3 and 6 months, respectively, after initiation of estrogen replacement therapy (ERT), which was significantly greater than the respective value of urinary excretion of deoxypyridinoline (DPD) (27.8% ± 4.1%, 34.1% ± 4.9%, respectively) or pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) assay (14.5% ± 4.1%, 13.1% ± 5.0%, respectively). The percent reduction in serum -CTx at 1, 3, and 6 months after initiation of ERT was significantly correlated in a negative manner with the percent increase in spinal BMD at 6 months. Further, ROC analysis to determine the significance of the percent change in bone resorption markers after 3 months of ERT in predicting the gain in spine BMD after 6 months suggested that serum -CTx and urinary DPD might provide a more discriminating indicator than serum ICTP. In conclusion, the findings suggest that the Elecsys -CrossLaps/serum assay provides a sensitive, and thus useful, tool for assessing bone resorption state in Japanese patients.     

Spine and femur densitometry at the menopause: Are both sites necessary in the assessment of the risk of osteoporosis?

Summary The aim of our study was to compare the results provided by the measurement of vertebral and femoral bone mineral density (BMD) for assessing the individual risk of osteoporosis as defined by either low BMD and/or rapid bone loss. Vertebral and femoral BMD were measured twice at a mean interval of 21 months in 85 normal, early post-menopausal women who had passed a natural menopause 6 months to 3 years previously. According to the measurement site, 36% (spine), 29% (femoral neck), 35% (Ward's triangle), and 25% (trochanter) fall in the at risk category, defined by a BMD value of 1 SD or more below the normal values for premenopausal women. Based on vertebral BMD, 39–48% of the women at risk had a normal femoral BMD. On the other hand, 24–37% of the women classified at risk based on femoral BMD maintained a low risk at the vertebral level. The annual rate of bone loss was significantly greater for the Ward's triangle (-2.7±3.8%) and femoral neck (-2.1±2.5%) than for the spine (-1.5±2.1%) and trochanter (-1.5±3.4%). There was a significant relationship between the rate of loss measured at the spine and femoral levels (r=0.34–0.58). Among the 21 women with a rapid vertebral bone loss, 48–67% had a low bone loss at the femoral level and vice versa. The ratio between mean rate of loss and the precision of the measurement sites was greater for the spine (1.6) compared with the femur (1.1–0.71). Our results indicate that vertebral and femoral BMD measurements produce discordant results in assessing the individual risk for osteoporosis.     

Bone Mineral Density and Bone Turnover 10 Years After a Single 5 mg Dose or Two 5-Yearly Lower Doses of Zoledronate in Osteopenic Older Women: An Open-Label Extension of a Randomized Controlled Trial

Intravenous zoledronate reduces fracture risk (5 mg at 18-month intervals) and prevents bone loss (doses of 1 to 5 mg for 3 to >5 years), but the duration of action of a single 5 mg dose and the effects of lower doses beyond 5 years are unknown. We report the second open-label extension (years 5 to 10) of a 2-year randomized, multidose, placebo-controlled, double-blinded trial. A total of 116 older women who completed 5 years of participation either continued observation without further treatment (zoledronate 5 mg and placebo at baseline) or received repeat doses of 1 or 2.5 mg zoledronate (zoledronate 1 mg and zoledronate 2.5 mg at baseline, respectively). Outcomes were spine, hip, and total body bone mineral density (BMD) and serum markers of bone turnover. After a single 5 mg dose of zoledronate, mean BMD at the lumbar spine and total hip was maintained at or above baseline levels for 9 and 10 years, respectively. The mean level of the bone resorption marker β-C-terminal telopeptide of type I collagen (β-CTX) was at least 25% lower than that in the placebo group for 9 years. In women administered 5-yearly doses of 2.5 mg zoledronate, mean BMD at the total hip and lumbar spine was maintained at or above baseline levels for 9 and 10 years, respectively. Redosing with 1 or 2.5 mg zoledronate at 5 years reduced bone turnover markers for 3 to 4 years. BMD increased for 3 to 4 years after redosing with 1 mg zoledronate. In the group given 5-yearly 2.5 mg zoledronate, β-CTX was at least 20% lower than that in the placebo group for 10 years. Both a single baseline 5 mg dose of zoledronate and 5-yearly doses of 1 and 2.5 mg zoledronate prevented bone loss at hip and spine for 8 to 10 years in older postmenopausal women. Clinical trials to evaluate the effects on fracture risk of these very infrequent and lower doses of zoledronate are justified. © 2021 American Society for Bone and Mineral Research (ASBMR).     

Pulsed estrogen therapy in prevention of postmenopausal osteoporosis. A 2-year randomized,double blind,placebo-controlled study

The aim of this study was to evaluate the efficacy of pulsed estrogen therapy (intranasal 17-estradiol) in the prevention of postmenopausal bone loss. A total of 386 women (40–65 years old), less than 5 years past menopause, were randomized to intranasal placebo, 17-estradiol 150 µg, or 300 µg daily for 2 years. Women with an intact uterus received micronised progesterone 200 mg per day, 14 days of each 28-day cycle. Women randomised to placebo-treatment received placebo progesterone. The primary endpoints were changes in BMD at the spine (L2–L4) and femoral neck. Secondary endpoints were changes in bone turnover markers: serum osteocalcin (sOC) as a marker of bone formation and urinary C-terminal telopeptides (uCTX) as a marker of bone resorption. BMD increased at all measured sites in women receiving active treatment in a dose-related manner, the difference compared to placebo being 5.2% and 6.7% at the spine, and 3.2% and 4.7 % at the hip, respectively, with 150 g and 300 g (P<0.001). On the other hand, a decrease versus baseline of –3.2% and –3.3% at the spine and hip, respectively, was observed in women receiving placebo (P<0.001). In the patients with at least one risk factor for osteoporotic fracture, the difference between placebo and 150 g or 300 µg was even higher at the spine (5.4% and 7.4%, respectively), and at the femoral neck (4.0% and 5.2%, respectively). Correspondingly, uCTX decreased from baseline by 39% and 46 %, and sOC by 22% and 27%, in the 150 µg group and 300 µg group (all P<0.001 versus placebo). A strong correlation was found between variations of bone turnover markers after 1 year and BMD after 2 years, emphasizing that bone markers can predict BMD response during hormonal treatment. Acceptability and general tolerance were good. This study demonstrates that pulsed estrogen therapy at the dose of 150 g and 300-g per day prevents bone loss in a dose-dependant manner at each site studied, and normalizes bone turnover markers to premenopausal levels.     

Skeletal health in adult patients with classic galactosemia

Summary

This study evaluated bone health in adults with galactosemia. Associations between bone mineral density (BMD) and nutritional and biochemical variables were explored. Calcium level predicted hip and spine BMD, and gonadotropin levels were inversely associated with spinal BMD in women. These results afford insights into management strategies for these patients.

Introduction

Bone loss is a complication of galactosemia. Dietary restriction, primary ovarian insufficiency in women, and disease-related alterations of bone metabolism may contribute. This study examined relationships between clinical factors and BMD in patients with galactosemia.

Methods

This cross-sectional sample included 33 adults (16 women) with classic galactosemia, mean age 32.0?±?11.8 years. BMD was measured by dual-energy X-ray absorptiometry, and was correlated with age, height, weight, fractures, nutritional factors, hormonal status, and bone biomarkers.

Results

There was a significant difference in hip BMD between women and men (0.799 vs. 0.896 g/cm², p?=?0.014). The percentage of subjects with BMD-Z <?2.0 was also greater for women than men [33 vs. 18 % (spine), 27 vs. 6 % (hip)], and more women reported sustaining fractures. Bivariate analyses yielded correlations between BMI and BMD-Z [at the hip in women (r?=?0.58, p?<?0.05) and spine in men (r?=?0.53, p?<?0.05)]. In women, weight was also correlated with BMD-Z (r?=?0.57, p?<?0.05 at hip), and C-telopeptides (r?=??0.59 at spine and ?0.63 hip, p?<?0.05) and osteocalcin (r?=??0.71 at spine and ?0.72 hip, p?<?0.05) were inversely correlated with BMD-Z. In final regression models, higher gonadotropin levels were associated with lower spinal BMD in women (p?=?0.017); serum calcium was a significant predictor of hip (p?=?0.014) and spine (p?=?0.013) BMD in both sexes.

Conclusions

Bone density in adults with galactosemia is low, indicating the potential for increased fracture risk, the etiology of which appears to be multifactorial.     

Effects of Transdermal Estradiol Delivered by a Matrix Patch on Bone Density in Hysterectomized,Postmenopausal Women: A 2-year Placebo-Controlled Trial

This 2-year, double-masked, randomized, placebo-controlled trial was designed to evaluate the safety and efficacy in preventing bone loss in postmenopausal women of two doses of transdermal 17β-estradiol (estradiol) delivered by a matrix patch, compared with placebo. One hundred and sixty healthy, hysterectomized postmenopausal volunteers aged 40–60 years with serum estradiol levels <20 pg/ml were started on treatment at four centers in The Netherlands. Every 6 months, bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, non-dominant wrist and left hip, and markers of bone turnover were assessed in urine and serum. The treatment arms were: estradiol, 100 mg/day (E-100, n= 53), oestradiol, 50 mg/day (E-50, n= 54), placebo (P-100, placebo to E-100, n= 27 or P-50, placebo to E-50, n= 26). Treatment was continued for up to 2 years. After 24 months, BMD of the lumbar spine in the E-100 group differed by 7.7% [5.8–9.5%] (mean [95% confidence interval]) from the placebo group and showed a mean (s.e.m.) increase in BMD from baseline of 5.9% (0.69%). For the E-50 group the difference compared with placebo was 6.2% [4.4–8.0%] and the absolute increase was 4.5% (0.62%); in the placebo group, the absolute change was –2.3% (0.48%). In the total wrist, the changes were: E-100: difference compared with placebo 2.5% [1.5–3.6%], absolute increase 0.6% (0.3%); E-50: difference compared with placebo 2.9% [1.8–3.9%], absolute increase 0.7% (0.25%); and absolute change on placebo: –2.5% (0.35%). In the total hip, the changes were: E-100: difference compared with placebo 3.7% [2.2–5.2%], absolute increase 2.8% (0.5%); E-50: difference compared with placebo: 3.2% [1.8–4.7%], absolute change 2.4% (0.36%); and absolute change on placebo –1.4% (0.66%). Three markers of bone turnover – serum bone-specific alkaline phosphatase, serum osteocalcin and urinary CTX – fell significantly during the trial. Breast pain was reported by 8% of women on placebo, by 6% of women on E-50 and by 17% of women on E-100. Estradiol delivered by the E-50 matrix patch effectively reversed bone loss in hysterectomized postmenopausal women with few side-effects. The marginal additional gain in BMD with the higher dose may be offset by a more important side effect profile. Received: 9 May 2001 / Accepted: 29 August 2001     

The effects of weight loss approaches on bone mineral density in adults: a systematic review and meta-analysis of randomized controlled trials

Summary

We assessed the impact of weight loss strategies including calorie restriction and exercise training on BMD in adults using a systematic review of randomized controlled trials. Weight reduction results in reduced BMD at the hip, but has less effect on the spine. Both calorie restriction and a combination of calorie restriction and exercise result in a decrease in hip bone density, whereas weight loss response to exercise training without dietary restriction leads to increased hip BMD.

Introduction

Findings are not consistent on the effect of weight loss on bone mineral density (BMD). We conducted a systematic review on the randomized controlled trials to assess the effect of weight loss strategies, including calorie restriction and exercise programs on BMD in adults.

Methods

A structured and comprehensive search of MEDLINE and EMBASE databases was undertaken up to March 2016. Study-specific mean differences (MD) were pooled using a random-effects model. Subgroup analysis and meta-regression were used to find possible sources of between-study heterogeneity.

Results

Thirty-two randomized controlled trials met predetermined inclusion criteria. The meta-analysis revealed no significant difference on total BMD (MD 0.007, 95 % CI ?0.020–0.034, p?=?0.608). In contrast, the pooled data of studies showed a significant effect of weight loss on hip BMD (MD ?0.008, 95 % CI ?0.09 to ?0.006 g/cm², p?<?0.001) and also lumbar spine BMD (MD ?0.018 g/cm², 95 % CI ?0.019 to ?0.017, p?<?0.001). BMD in the hip site decreased after more than 4 months, especially in those who were obese. Moreover, calorie restriction interventions longer than 13 months showed a significant decreased in lumbar spine BMD.

Conclusion

Weight loss led to significant decreases at the hip and lumbar spine BMD but not at the total. Weight loss response following calorie restriction resulted in a decrease in hip and lumbar spine bone density especially more than 1 year; whereas an exercise-induced weight loss did not.

     

Effect of once-yearly zoledronic acid on the spine and hip as measured by quantitative computed tomography: results of the HORIZON Pivotal Fracture Trial

Summary

Changes in bone mineral density and bone strength following treatment with zoledronic acid (ZOL) were measured by quantitative computed analysis (QCT) or dual-energy X-ray absorptiometry (DXA). ZOL treatment increased spine and hip BMD vs placebo, assessed by QCT and DXA. Changes in trabecular bone resulted in increased bone strength.

Introduction

To investigate bone mineral density (BMD) changes in trabecular and cortical bone, estimated by quantitative computed analysis (QCT) or dual-energy X-ray absorptiometry (DXA), and whether zoledronic acid 5 mg (ZOL) affects bone strength.

Methods

In 233 women from a randomized, controlled trial of once-yearly ZOL, lumbar spine, total hip, femoral neck, and trochanter were assessed by DXA and QCT (baseline, Month 36). Mean percentage changes from baseline and between-treatment differences (ZOL vs placebo, t-test) were evaluated.

Results

Mean between-treatment differences for lumbar spine BMD were significant by DXA (7.0%, p?<?0.01) and QCT (5.7%, p?<?0.0001). Between-treatment differences were significant for trabecular spine (p?=?0.0017) [non-parametric test], trabecular trochanter (10.7%, p?<?0.0001), total hip (10.8%, p?<?0.0001), and compressive strength indices at femoral neck (8.6%, p?=?0.0001), and trochanter (14.1%, p?<?0.0001).

Conclusions

Once-yearly ZOL increased hip and spine BMD vs placebo, assessed by QCT vs DXA. Changes in trabecular bone resulted in increased indices of compressive strength.     

Efficacy and safety of bazedoxifene in postmenopausal Asian women

Summary

This 6-month study examined the efficacy and safety of bazedoxifene 20?mg in postmenopausal Asian women. Bazedoxifene showed statistically significant improvements over placebo in bone mineral density at all skeletal sites evaluated. Bazedoxifene significantly reduced bone turnover and had favorable effects on lipid parameters. Bazedoxifene was safe and well tolerated.

Introduction

This 6-month, randomized, double-blind, placebo-controlled phase 3 study conducted in China, Korea, and Taiwan evaluated the efficacy and safety of bazedoxifene in postmenopausal Asian women.

Methods

Generally, healthy postmenopausal Asian women (N?=?487; mean age, 57.2?years; mean lumbar spine bone mineral density [BMD], ?1.1) were randomized to daily therapy with bazedoxifene 20?mg or placebo; all subjects received daily supplemental calcium carbonate 600?mg. The changes from baseline in BMD at the lumbar spine (primary end point) and at other skeletal sites, bone turnover markers, and lipid parameters were evaluated at 6?months. Safety assessments included adverse event (AE) reporting and physical/gynecologic examination.

Results

At 6?months, women who received bazedoxifene 20?mg had significantly greater BMD compared with those receiving placebo at the lumbar spine (0.41% vs ?0.32%, P?<?0.01), femoral neck (?0.08% vs ?0.69%, P?=?0.014), trochanter (0.50% vs ?0.23%, P?=?0.010), and total hip (?0.03% vs ?0.77%, P?<?0.001), respectively. Bazedoxifene 20?mg was also associated with significant differences from placebo in median percent reductions from baseline in serum C-telopeptide (?21.8%, P?<?0.001) and osteocalcin (?12.9%, P?<?0.001) levels and total (?5.0%, P?<?0.001) and low-density lipoprotein cholesterol (?9.5%, P?<?0.001) levels. The incidence of AEs was not different between subjects treated with bazedoxifene and those who received placebo.

Conclusion

Bazedoxifene was generally safe and effective in preventing bone loss in this short-term study of postmenopausal Asian women.     

Absorption of the oral bisphosphonate alendronate in osteoporotic patients with Crohn’s disease

The absorption of bisphosphonates from the gut is poor. The question arises whether the absorption of alendronate, and thus its bioavailability, is further altered by the local inflammatory process in patients with Crohns disease, thereby potentially affecting clinical outcome when used in the treatment of osteoporosis. To address this question, urinary excretion of alendronate was evaluated 3 months and 6 months after start of treatment with oral alendronate at a dose of 10 mg/day in 19 osteoporotic patients with stable Crohns disease, 12 of whom had an intestinal resection. Biochemical parameters of bone turnover and BMD were also measured at start and at 6 months. Thirteen patients had been previously treated with glucocorticoids and five were currently using them. The average 24-h urinary excretion of alendronate was 0.5–0.6% of the dose administered, a figure comparable to that reported for osteoporotic patients without gut pathology. There was a significant decrease from baseline in urine N-telopeptides of collagen cross-links (NTx)/creatinine (60%) associated with an increase in lumbar spine BMD of already 2% after 6 months of treatment. Our data suggest that in patients with Crohns disease, alendronate is adequately absorbed from the intestine and retained in the skeleton. This adequacy is confirmed by appropriate suppression of bone resorption and increase in lumbar spine BMD. These data hold significant implications for the clinical management of patients with Crohns disease and osteoporosis.     

Osteoporosis and transforming growth factor-beta-1 gene polymorphism in Chinese men and women

Transforming growth factor-beta-1 (TGF-₁) has been implicated in bone mineral density (BMD) determination. We investigated the relationship between the TGF polymorphism, BMD, and vertebral fractures in 588 Chinese men and women. No association between TGF polymorphism and BMD was observed in postmenopausal women (aged 55–59 years), elderly men (aged 70–79 years), or elderly women (aged 70–79 years) at the hip, spine, or total body (P 0.05 by two-way ANOVA). In all study groups, there was no effect of an interaction between TGF polymorphism and calcium intake on BMD (P 0.05 for the interaction effects by two-way ANOVA). No statistical significant association was observed between TGF polymorphism and vertebral fracture in elderly men or women (P 0.05 by the chi-square test), even though men of the TT and TC genotypes seem to have more vertebral fractures. Contrary to previous studies that found an association between BMD and TGF polymorphism in the Japanese, we found no association between TGF polymorphism and BMD of elderly Chinese men or women. This finding could result from different sampling methods between the previous and current studies and environmental factors and ethnic differences between the two populations.     

Randomized trial of effect of alendronate continuation versus discontinuation in women with low BMD: results from the Fracture Intervention Trial long-term extension.

To determine the effects of continuation versus discontinuation of alendronate on BMD and markers of bone turnover, we conducted an extension trial in which 1099 older women who received alendronate in the FIT were re-randomized to alendronate or placebo. Compared with women who stopped alendronate, those continuing alendronate for 3 years maintained a higher BMD and greater reduction of bone turnover, showing benefit of continued treatment. However, among women who discontinued alendronate and took placebo in the extension, BMD remained higher, and reduction in bone turnover was greater than values at FIT baseline, showing persistence of alendronate's effects on bone. INTRODUCTION: Prior trials including the Fracture Intervention Trial (FIT) have found that therapy with alendronate increases BMD and decreases fracture risk for up to 4 years in postmenopausal women with low BMD. However, it is uncertain whether further therapy with alendronate results in preservation or further gains in BMD and if skeletal effects of alendronate continue after treatment is stopped. MATERIALS AND METHODS: We conducted a follow-up placebo-controlled extension trial to FIT (FIT long-term extension [FLEX]) in which 1099 women 60-86 years of age who were assigned to alendronate in FIT with an average duration of use of 5 years were re-randomized for an additional 5 years to alendronate or placebo. The results of a preplanned interim analysis at 3 years are reported herein. Participants were re-randomized to alendronate 10 mg/day (30%), alendronate 5 mg/day (30%), or placebo (40%). All participants were encouraged to take a calcium (500 mg/day) and vitamin D (250 IU/day) supplement. The primary outcome was change in total hip BMD. Secondary endpoints included change in lumbar spine BMD and change in markers of bone turnover (bone-specific alkaline phosphatase and urinary type I collagen cross-linked N-telopeptide). RESULTS: Among the women who had prior alendronate therapy in FIT, further therapy with alendronate (5 and 10 mg groups combined) for 3 years compared with placebo maintained BMD at the hip (2.0% difference; 95% CI, 1.6-2.5%) and further increased BMD at the spine (2.5% difference; 95% CI, 1.9-3. 1%). Markers of bone turnover increased among women discontinuing alendronate, whereas they remained stable in women continuing alendronate. Cumulative increases in BMD at the hip and spine and reductions in bone turnover from 8.6 years earlier at FIT baseline were greater for women continuing alendronate compared with those discontinuing alendronate. However, among women discontinuing alendronate and taking placebo in the extension, BMD remained higher and reduction in bone turnover was greater than values at FIT baseline. CONCLUSIONS: Compared with women who stopped alendronate after an average of 5 years, those continuing alendronate maintained a higher BMD and greater reduction of bone turnover, showing benefit of continued alendronate treatment on BMD and bone turnover. On discontinuation of alendronate therapy, rates of change in BMD at the hip and spine resumed at the background rate, but discontinuation did not result in either accelerated bone loss or a marked increase in bone turnover, showing persistence of alendronate's effects on bone. Data on the effect of continuation versus discontinuation on fracture risk are needed before making definitive recommendations regarding the optimal length of alendronate treatment.     

Odanacatib,a cathepsin‐K inhibitor for osteoporosis: A two‐year study in postmenopausal women with low bone density

Cathepsin K, a cysteine protease expressed in osteoclasts, degrades type 1 collagen. Odanacatib selectively and reversibly inhibited cathepsin K and rapidly decreased bone resorption in preclinical and phase I studies. A 1‐year dose‐finding trial with a 1‐year extension on the same treatment assignment was performed in postmenopausal women with low bone mineral density (BMD) to evaluate the safety and efficacy of weekly doses of placebo or 3, 10, 25, or 50 mg of odanacatib on BMD and biomarkers of skeletal remodeling. Women with BMD T‐scores of ?2.0 or less but not less than ?3.5 at the lumbar spine or femoral sites were randomly assigned to receive placebo or one of four doses of odanacatib; all received vitamin D with calcium supplementation as needed. The primary endpoint was percentage change from baseline lumbar spine BMD. Other endpoints included percentage change in BMD at hip and forearm sites, as well as changes in biomarkers of skeletal remodeling. Twenty‐four months of treatment produced progressive dose‐related increases in BMD. With the 50‐mg dose of odanacatib, lumbar spine and total‐hip BMD increased 5.5% and 3.2%, respectively, whereas BMD at these sites was essentially unchanged with placebo (?0.2% and ?0.9%). Biochemical markers of bone turnover exhibited dose‐related changes. The safety and tolerability of odanacatib generally were similar to those of placebo, with no dose‐related trends in any adverse experiences. In summary, 2 years of weekly odanacatib treatment was generally well‐tolerated and increased lumbar spine and total‐hip BMD in a dose‐related manner in postmenopausal women with low BMD. © 2010 American Society for Bone and Mineral Research     

Bone loss is more severe in primary adrenal than in pituitary-dependent Cushing’s syndrome

Either exogenous or endogenous glucocorticoid excess is an established cause of osteoporosis and fractures. Glucocorticoids exert their negative effects on bone through mechanisms that are not yet completely elucidated; however, as many as 50% of patients with Cushings syndrome suffer from osteoporosis. Bone loss induced by glucocorticoids is potentially reversible after resolution of glucocorticoid excess. It is presently unknown if Cushings disease (CD) sustained by a pituitary ACTH-producing adenoma and adrenal-dependent Cushings syndrome (ACS) sustained by an adrenocortical adenoma have a different potential of inducing osteopenia. The aim of the present study was to retrospectively analyze bone mineral density (BMD) in 26 patients with CD (4 men, 22 women, aged 14–79 years), 12 patients with ACS (4 men, 8 women, aged 32–79 years) and 38 healthy subjects carefully matched for sex, age and body mass index (BMI). Measurement of BMD was performed by dual-energy X-ray absorptiometry (DXA) using the Hologic QDR 4500 W instrument. Data were analyzed using absolute BMD values (g/cm²), T-score and Z-score referred to the manufacturers normative data for the lumbar spine and to the NHANES III dataset for the hip. The patients with CD and ACS were comparable for age, BMI, estimated duration of disease, urinary free cortisol (UFC) levels, midnight serum cortisol and gonadal function. The analysis of variance demonstrated that lumbar bone densitometric parameters were significantly different among the three groups. They were more reduced in patients with ACS (BMD, 0.76±0.03 g/cm²; T-score, –2.78±0.28; Z-score, –2.25±0.30) while patients with CD (BMD, 0.87±0.02 g/cm²; T-score, –1.74±0.24; Z-score, –0.99±0.32) showed DXA values between the first group and controls (BMD, 1.02±0.02 g/cm²; T-score, –0.35±0.19; Z-score, 0.33±0.16). The difference in BMD at the spine remained statistically significant (P=0.04) after adjustment for the non-significant differences in age, UFC and fat mass between CD and ACS. Conversely, femoral bone densitometric parameters were not significantly different between patients with ACS and CD, even if they were more reduced than in controls. In patients with ACS, we observed a reduction of DHEA-S levels, expressed as standard score (Z-score) values referred to a group of 180 healthy subjects stratified by sex and different age groups (<40 years, between 40 and 60 years, >60 years) to circumvent the pronounced effect of gender and age on such hormone (ACS DHEA-S Z-score -0.88±1.4 versus CD DHEA-S Z-score 2.25±2.35, P=0.0001). DHEA-S Z-score values were significantly correlated with lumbar BMD (r=0.41, P=0.02) and femoral BMD (r=0.43, P=0.01). DHEA-S Z-score values were also significantly correlated with osteocalcin levels (r=0.45, P=0.01). Our data suggest that bone loss is greater in ACS than in CD. A plausible explanation comes from the reduced DHEA-S level in ACS since DHEA-S has well known anabolic actions on bone. However, this hypothesis needs to be confirmed in large, prospective series of patients with Cushings syndrome of different etiology.     

Periprosthetic bone remodelling of two types of uncemented femoral implant with proximal hydroxyapatite coating: a 3-year follow-up study addressing the influence of prosthesis design and preoperative bone density on periprosthetic bone loss

Periprosthetic bone loss is a major cause of concern in patients undergoing total hip arthroplasty (THA). Further studies are required to identify the factors determining the pattern of bone remodelling following THA and obtain improvements in the design and durability of prostheses. In this study, we monitored periprosthetic bone loss around two different types of hydroxyapatite coated femoral implant over a 3-year period to evaluate their design and investigate the relationship with the preoperative bone mineral density (BMD) at the spine, hip and forearm. Sixty patients (35 F, 25 M, mean age 63 years, range 46–75 years) undergoing THA were randomised to either the Anatomic Benoist Girard (ABG) or Mallory-Head (MH) femoral stem. Preoperative dual-energy X-ray absorptiometry (DXA) scans were acquired of the posteroanterior (PA) and lateral lumbar spine, the contralateral hip and the non-dominant forearm. Postoperative DXA scans were performed to measure periprosthetic BMD at 10 days (treated as baseline), 6 weeks, and 3, 6, 12, 24 and 36 months after THA using a standard Gruen zone analysis. Results were expressed as the percentage change from baseline and the data examined for the differences in bone loss between the different Gruen zones, between the ABG and MH stems, and the relationship with preoperative BMD. A total of 50 patients (24 ABG, 26 MH) completed the study. Three months after THA there was a statistically significant BMD decrease in every Gruen zone that varied between 5.6% and 13.8% for the ABG prosthesis and between 3.8% and 8.7% for the MH prosthesis. Subsequently, in most zones BMD reached a plateau or showed a small recovery. However, BMD continued to fall in Gruen zones 1 and 7 in ABG patients and Gruen zone 1 in MH patients. Bone loss was less in every Gruen zone in MH patients compared with ABG with the largest difference (10%, P=0.018) in Gruen zone 7. Highly significant relationships were found between periprosthetic bone loss and preoperative BMD measured at the PA spine (P<0.001), total hip (P=0.004) and total distal radius (P<0.001). This study showed differences between two different designs of hydroxyapatite-coated implant that confirmed that prosthesis design influences periprosthetic bone loss. The study also showed that patients bone density measured at the spine, hip or forearm at the time of operation was a major factor influencing bone loss around the femoral stem.     

The efficacy and tolerability of risedronate on bone mineral density and bone turnover markers in osteoporotic Chinese women: a randomized placebo-controlled study

Osteoporosis has become an important health problem in postmenopausal Asian populations as the prevalence of hip and vertebral fractures in some Asian countries has risen to approach that of Caucasian populations. Risedronate, a pyridinyl-bisphosphonate agent, is a potent inhibitor of bone resorption. Risedronate increases bone mineral density (BMD), reduces markers of bone turnover, and reduces the risk of fractures in Caucasian postmenopausal women. To determine the efficacy and tolerability of risedronate in Chinese, a multicenter, randomized, double blind, placebo controlled study was performed in Hong Kong. Sixty-five (65) postmenopausal osteoporotic Southern Chinese women, aged 67+/-6 years, were randomly assigned to receive either risedronate 5 mg daily (n=31) or placebo (n=34) for 12 months. All women received calcium carbonate 500 mg daily and vitamin D 400 IU daily. Mean baseline BMD T-score at the spine and total hip was -3.4 and -2.6, respectively. A significant increase in spine BMD was already evident at month 3 of risedronate treatment (P<0.001). Risedronate significantly increased BMD and reduced bone turnover markers as compared with placebo. The risedronate group had significant increase in BMD at 12 months at both the spine and hip when compared with the placebo group (L1-4 6.6% vs. 0.4%, P<0.001; total hip 2.7% vs. 0.3, P<0.0001; femoral neck 1.8% vs. 1.1%, P<0.02; trochanter 4% vs. 1.1%, P<0.0001, respectively). Significant changes in urine N-telopeptide (NTx) and serum osteocalcin were evident as early as 1 and 3 months, respectively, with risedronate treatment. No significant changes were seen in both BMD and bone markers in the placebo group. Risedronate was well tolerated without major adverse effects. We conclude that risedronate is an effective and well-tolerated agent for the treatment of postmenopausal osteoporosis in Asian population.