Half the burden of fragility fractures in the community occur in women without osteoporosis. When is fracture prevention cost-effective?

Serial assessment of serum bone metabolism markers identifies women with the highest rate of bone loss and osteoporosis risk

CONTEXT

One of the important challenges in the management of osteoporosis is to identify women who are at high risk of developing osteoporosis and fragility fractures.

OBJECTIVE

Our objective was to evaluate whether assessment of bone metabolism at multiple occasions can identify women with the highest risk for bone loss.

DESIGN

The Malmö Osteoporosis Prospective Risk Assessment study is an ongoing longitudinal study. Participants have been evaluated at baseline and after 1, 3, and 5 yr.

SETTING

We conducted a population-based study.

PARTICIPANTS

Participants included 1044 women, all 75 yr old at baseline.

MAIN OUTCOME MEASURES

Seven bone turnover markers were assessed at baseline and at 1, 3, and 5 yr (n = 573). The 5-yr change in areal bone mineral density (aBMD) was also determined.

RESULTS

Baseline markers correlated weakly to change in total body aBMD. The associations were more pronounced when the average of the baseline and 1-yr measurements was used (standardized regression coefficients -0.12 to -0.23, P < 0.01). Adding the 3-yr and 5-yr measurement further strengthened the correlation (regression coefficients up to -0.30, P < 0.001). Women with constantly high turnover lost significantly more bone at total body assessment (-2.6%) than women with intermediate (-1.6%) or low turnover (-0.2%, P for trend < 0.001). They also had a greater decrease in hip BMD (-8.3, -6.0, and -5.1%, respectively, P = 0.010). Results were similar also in the subgroup of women with osteopenia.

CONCLUSIONS

Our results suggest that serial assessment of bone turnover improves the identification of women with the highest rate of bone loss and osteoporosis risk.

Effects of risedronate on fracture risk in postmenopausal women with osteopenia

This posthoc analysis of four trials studied the efficacy of risedronate to reduce fragility fractures in postmenopausal women with osteopenia (i.e., T-scores between -1 and -2.5). Risedronate reduced the fracture risk by 73% (p = 0.023) in this population of women with low femoral neck bone mass and no prevalent vertebral fractures.

INTRODUCTION

Low bone mass represents an increasing health risk and burden. Half of fragility fractures occur in osteopenic women underscoring the need for treatments reducing fracture risk. This analysis reports the effect of risedronate to reduce fragility fracture risk in osteopenic women without prevalent vertebral fractures.

METHODS

Postmenopausal women with osteopenia, defined as femoral neck T-score between -1 and -2.5 by DXA and no prevalent vertebral fractures, were identified from four controlled randomized trials (BMD Multinational, BMD North America, VERT Multinational and VERT North America). The risk reduction for fragility fractures in patients receiving 5 mg risedronate daily for 1.5 to 3 years compared to placebo was assessed. An additional sensitivity analysis excluded patients who were osteopenic at the femoral neck but had a BMD lower than -2.5 SD at the lumbar spine.

RESULTS

Six hundred and twenty postmenopausal women with osteopenia were included, receiving either placebo (n = 309) or risedronate 5 mg (n = 311). Risedronate reduced the risk of fragility fractures by 73% over 3 years versus placebo (p = 0.023); cumulative fragility fracture incidence was 6.9% in placebo-treated versus 2.2% in risedronate-treated patients. The magnitude of the effect was similar in the sensitivity analysis subset.

CONCLUSION

Risedronate significantly reduced the risk of fragility fractures in postmenopausal women with osteopenia (femoral neck T-score between -1 and -2.5 SD) and no prevalent vertebral fractures.

Proceedings of the Eighth Annual Santa Fe Bone Symposium, August 3-4, 2007

The Eighth Annual Santa Fe Bone Symposium convened August 3-4, 2007, in Santa Fe, New Mexico, USA, immediately preceded by the Research Symposium in Metabolic Bone Disease and Osteoporosis Update for Endocrine Fellows, and followed by the International Society for Clinical Densitometry (ISCD) Bone Densitometry Course. The symposium faculty consists of internationally recognized experts in osteoporosis and metabolic bone disease who presented state-of-the-art research data and late-breaking developments in the fields of osteoporosis, metabolic bone disease, and assessment of skeletal health. The presentations and numerous interactive discussions that followed focused on applying what is known from clinical trials, knowledge of bone pathophysiology, and the mechanisms of action of therapeutic interventions, to making real-world patient management decisions. Topics included an update on reimbursement issues for bone density testing in the United States, a report on the 2007 ISCD Pediatric and Adult Position Development Conferences, present and future therapeutic concepts, new paradigms for fracture risk assessment and intervention thresholds, evaluation for secondary causes of osteoporosis, nonvertebral fracture risk reduction-medical evidence and clinical practice, epidemiological insights into the prevention of osteoporotic fractures, osteonecrosis of the jaw facts and fictions, and osteomalacia. Presented here are short essays based on the key clinical presentations of the 2007 Santa Fe Bone Symposium.

Implications of absolute fracture risk assessment for osteoporosis practice guidelines in the USA

Application of the WHO fracture prediction algorithm in conjunction with an updated US economic analysis indicates that osteoporosis treatment is cost-effective in patients with fragility fractures or osteoporosis, in older individuals at average risk and in younger persons with additional clinical risk factors for fracture, supporting existing practice recommendations.

INTRODUCTION

The new WHO fracture prediction algorithm was combined with an updated economic analysis to evaluate existing NOF guidance for osteoporosis prevention and treatment.

METHODS

The WHO fracture prediction algorithm was calibrated to the US population using national age-, sex- and race-specific death rates and age- and sex-specific hip fracture incidence rates from the largely white population of Olmsted County, MN. Fracture incidence for other races was estimated by ratios to white women and men. The WHO algorithm estimated the probability (%) of a hip fracture (or a major osteoporotic fracture) over 10 years, given specific age, gender, race and clinical profiles. The updated economic model suggested that osteoporosis treatment was cost-effective when the 10-year probability of hip fracture reached 3%.

RESULTS

It is cost-effective to treat patients with a fragility fracture and those with osteoporosis by WHO criteria, as well as older individuals at average risk and osteopenic patients with additional risk factors. However, the estimated 10-year fracture probability was lower in men and nonwhite women compared to postmenopausal white women.

CONCLUSIONS

This analysis generally endorsed existing clinical practice recommendations, but specific treatment decisions must be individualized. An estimate of the patient's 10-year fracture risk should facilitate shared decision-making.

Strontium ranelate reduces the risk of vertebral fractures in patients with osteopenia

Many fractures occur in women with moderate fracture risk caused by osteopenia. Strontium ranelate was studied in 1431 postmenopausal women with osteopenia. Vertebral fracture risk reduction of 41-59% was shown depending on the site and fracture status at baseline. This is the first report of antivertebral fracture efficacy in women with vertebral osteopenia.

INTRODUCTION

Women with osteoporosis are at high risk for fracture. However, more than one half of all fractures in the community originate from the larger population at more moderate risk of fracture caused by osteopenia. Despite this, evidence for antifracture efficacy in these persons is limited. The aim of this study was to determine whether strontium ranelate, a new drug that reduces fracture risk in women with osteoporosis, is also effective in women with osteopenia.

MATERIALS AND METHODS

Data from the Spinal Osteoporosis Therapeutic Intervention study (SOTI; n = 1649) and the TReatment Of Peripheral OSteoporosis (TROPOS; n = 5091) were pooled to evaluate the antivertebral fracture efficacy of strontium ranelate in women with lumbar spine (LS) osteopenia with any BMD value at the femoral neck (FN; N = 1166) and in 265 women with osteopenia at both sites (intention-to-treat analysis). The women were randomized to strontium ranelate 2 g/d orally or placebo for 3 yr.

RESULTS

No group differences were present in baseline characteristics that may influence fracture outcome independent of therapy. In women with LS osteopenia, treatment reduced the risk of vertebral fracture by 41% (RR = 0.59; 95% CI, 0.43-0.82), by 59% (RR = 0.41; 95% CI, 0.17-0.99) in the 447 patients with no prevalent fractures, and by 38% (RR = 0.62; 95% CI, 0.44-0.88) in the 719 patients with prevalent fractures. In women with osteopenia at both sites, treatment reduced the risk of fracture by 52% (RR = 0.48; 95% CI, 0.24-0.96).

CONCLUSIONS

Strontium ranelate safely reduces the risk of vertebral fractures in women with osteopenia with or without a prevalent fracture.

Differential effects of D-hormone analogs and native vitamin D on the risk of falls: a comparative meta-analysis

The aim of this meta-analysis was to compare the antifall efficacy of native vitamin D to that of its hydroxylated analogs alfacalcidol and calcitriol. Randomized clinical trials comparing oral native vitamin D and its analogs alfacalcidol and calcitriol to a placebo were included. Sources included the Cochrane Controlled Trials Register, EMBASE, MEDLINE, a hand search of abstracts, as well as reference lists. The time range was January 1995 to May 2007. Data were abstracted and scored by two investigators. The core analysis was based on double-blind trials, while open trials were included as a robustness analysis. Relative risks (RRs) for falls while allocated to D-hormone analogs or vitamin D were calculated. Publication bias and robustness were formally tested. Fourteen trials including 21,268 subjects were included. Using double-blind data only, vitamin D-hormone analogs provided a statistically significant lower level of risk for falling compared to native vitamin D: RR = 0.79 (95% confidence interval 0.64-0.96) vs. 0.94 (0.87-1.01) (intergroup difference P = 0.049). The dropout rates observed in the two sets of trials were comparable: 0.33% per month. Publication bias investigation did not report any significant trend for selective publication favoring active treatment arms. Upon current evidence, D-hormone analogs seem to prevent falls to a greater extent than their native compound. Long-term, prospective, head-to-head, confirmatory trials are required to address the exact role of vitamin D and D-hormone analogs in the prevention of falls and fractures.

Is treatment of early postmenopausal women with bisphosphonates justified?

The decision to treat women in the early postmenopausal period has come under scrutiny because of the low occurrence of fractures in this population and the possible lack of cost-effectiveness for individual patients. This article focuses on the potential use of bisphosphonates for the prevention and treatment of osteoporosis in the early postmenopausal period. Studies have determined that there is a relationship between bisphosphonate treatment and bone mineral density (BMD) gains, even in women in the early postmenopausal period without a diagnosis of osteoporosis. These patients receive benefit from treatment, including improvements in BMD levels and fracture protection. Using BMD scores, rates of bone turnover, and risk-based diagnostic criteria as part of the decision to initiate therapy may allow for the identification of an early postmenopausal patient population that would benefit from preventative therapy. This would improve the cost-effectiveness of using bisphosphonates for the prevention of osteoporosis in this population. The evaluation of women at risk for developing osteoporosis should include an assessment of both BMD scores and additional risk factors. Early postmenopausal women who are in a high-risk group should be considered candidates to receive bisphosphonate therapy.

The spinal curvature irregularity index independently identifies vertebral fractures

INTRODUCTION AND HYPOTHESIS

The spinal curvature irregularity index (SCII) is a quantitative measure of the irregularity of the spinal curvature. We evaluated the predictive ability of SCII to identify subjects with vertebral fractures (VF).

METHODS

Vertebral heights were measured by quantitative vertebral morphometry in 461 Lebanese women 20-89 years of age and VFs were ascertained by the grade 1 Eastell method. SCII scores were log-transformed and expressed as Z-SCII, the number of standard deviations above or below the mean ln(SCII) of young patients without VF. Univariate and multivariate binary logistic regression models were used to identify clinical predictors of VF.

RESULTS

Women with a higher SCII were more likely to have prevalent VF. A higher SCII was associated with a greater prevalence of VF within each category of femoral neck BMD (normal, osteopenia, osteoporosis). In univariate analysis, predictors of VF included Z-SCII (odds ratio, OR: 2.21, 95% CI: 1.80-2.71) and femoral neck T-score (OR: 1.35, 95% CI: 1.12-1.63). In multivariate analysis, predictors of VF were: Z-SCII (OR: 1.54, 95% CI: 1.02-2.32), femoral neck T-score (OR: 1.41, 95% CI: 1.11-1.78) and age(3) (OR: 1.40, 95% CI 1.10-1.82). At a cutoff SCII of 9.5%, the sensitivity and specificity of SCII for VF were 71 and 64% respectively, and higher SCII cutoffs identified VFs with greater specificity.

CONCLUSION

The SCII is a robust, simple and independent indicator of the presence of VFs.

Using computers to identify non-compliant people at increased risk of osteoporotic fractures in general practice: a cross-sectional study

BACKGROUND

National guidelines recommend bisphosphonates for secondary prevention of osteoporotic fractures; however, poor compliance may result in sub-optimal prevention.

OBJECTIVE

This study reports the feasibility of using GP electronic records to identify poorly compliant post-menopausal women who may be at increased risk of fragility fractures.

DESIGN

Cross-sectional study of general practice computer records.

SUBJECTS

Women over 45 years, registered in 29 practices across England with a total population of approximately 200,000.

METHODS

MIQUEST (Morbidity Information Query and Export Syntax) a data extraction application was used to extract prescription, diagnostic data and probable fragility fractures (hip, vertebral, wrist). All women >45 years who received a first prescription for a weekly bisphosphonate (alendronate or risedronate) at least a year before data extraction were identified. Each record was examined to determine the number of days of prescribed treatment.

RESULTS

Of 97992 registered women, 44% (42734) were >45 years. Prevalence of likely fragility fractures in women over 45 was 5.1% (2195/42734). 3.0% (1286/42734, mean age 72 years) received a prescription for a bisphosphonate in the 360 day period prior to data extraction with a median duration of treatment of 267 days. 45% (584/1286) received prescriptions covering >288/360 days (Medicine Possession Ratio >80%); 13% (161/1286) collected prescriptions covering >360 days. In those prescribed bisphosphonates, 23% (294/1286) had a likely fragility fracture.

CONCLUSIONS

Women >45 years with probable fragility fractures are more likely to be prescribed bisphosphonates, though less than half will be actually taking them as prescribed. GPs should use computer technology to identify poorly compliant patients who are unnecessarily at risk of fracture.

What is the number of older Canadians needed to screen by measurement of bone density to detect an undiagnosed case of osteoporosis? a population-based study from CaMos

Routine bone mineral densitometry (BMD) screening has been recommended for women aged >or=65 yr (Osteoporosis Canada [OC], International Society for Clinical Densitometry [ISCD], Canadian and United States Task Forces on Preventative Healthcare, and National Osteoporosis Foundation) and for men >or=65 yr (OC) or >or=70 yr (ISCD). We estimated the number of older Canadians needed to screen (NNS) by BMD to detect an undiagnosed case of osteoporosis, using prospective, multicenter, population-based data from the Canadian Multicentre Osteoporosis Study (CaMos). We included participants aged >or=65 yr with baseline dual-energy X-ray absorptiometry (DXA) BMDs at the femoral neck and lumbar spine (L1-L4). Osteoporosis was defined by a T-score <or=2.5 at either site. Patients were questioned about a prior diagnosis of osteoporosis. We studied 2699 women and 1032 men aged >or=65 yr. The percentage prevalence and 95% confidence intervals were determined. In individuals aged >or=65 yr, the prevalence of osteoporosis was 25.6% in women (95% confidence interval, 24.0%, 27.3%) and 8.9% in men (7.3%, 10.8%). In 652 men aged >or=70 yr, the prevalence of osteoporosis was 11.3% (9.1%, 14.0%). Of the participants with BMD-defined osteoporosis, 76.6% of woman aged >or=65 yr (73.2%, 79.6%; 516 of 674 women), 93.4% of men aged >or=65 yr (86.4%, 96.9%; 85 of 91), and 93.2% of men >or=70 yr (84.9%, 97.0%; 68 of 73) were not aware of it. Thus, the minimum NNS by BMD testing to detect one previously undiagnosed case of osteoporosis in Canada is: 6 women aged >or=65 yr, 13 men aged >or=65 yr, and 10 men aged >or=70 yr.

Osteoporosis update: effective prevention and treatment

Osteoporosis is a public health threat to approximately 44 million individuals in the USA, or 55% of men and women over the age of 50 years. The primary goal of osteoporosis management is to prevent fracture, the most devastating consequence. Risk factors and bone mineral density can be assessed to determine appropriate action for prevention and treatment of osteoporosis. Prevention strategies include lifestyle modification, fall prevention, and adequate intake of calcium and vitamin D. Current treatment options include antiresorptive agents and anabolic agents. Adherence and cost issues play major roles in establishing optimal therapy for individual patients. New agents in development are designed to improve osteoporosis treatment and patient adherence. This review focuses on current and future prevention and treatment options for postmenopausal osteoporosis.

Strontium ranelate reduces the risk of vertebral and nonvertebral fractures in women eighty years of age and older

Strontium ranelate produces an early and sustained reduction of both vertebral and nonvertebral fractures in patients > or = 80 years of age.

INTRODUCTION

About 25-30% of the population burden of all fragility fractures in the community arise from women > or = 80 years of age, because this population is at high risk for all types of fracture, particularly nonvertebral fractures. Despite this, evidence that therapies reduce the risk of both vertebral and nonvertebral fractures in this group is lacking. The aim of this study was to determine whether strontium ranelate, an agent that reduces the risk of vertebral and nonvertebral fractures in postmenopausal women >50 years of age, also reduces fractures in the elderly.

MATERIALS AND METHODS

An analysis based on preplanned pooling of data from two international, phase III, randomized, placebo-controlled, double-blind studies (the Spinal Osteoporosis Therapeutic Intervention [SOTI] and TReatment Of Peripheral OSteoporosis [TROPOS]) included 1488 women between 80 and 100 years of age followed for 3 years. Yearly spinal X-rays were performed in 895 patients. Only radiographically confirmed nonvertebral fractures were included.

RESULTS

Baseline characteristics did not differ in placebo and treatment arms. In the intent-to-treat analysis, the risk of vertebral, nonvertebral, and clinical (symptomatic vertebral and nonvertebral) fractures was reduced within 1 year by 59% (p = 0.002), 41% (p = 0.027), and 37% (p = 0.012), respectively. At the end of 3 years, vertebral, nonvertebral, and clinical fracture risks were reduced by 32% (p = 0.013), 31% (p = 0.011), and 22% (p = 0.040), respectively. The medication was well tolerated, and the safety profile was similar to that in younger patients.

CONCLUSIONS

Treatment with strontium ranelate safely reduces the risk of vertebral and nonvertebral fractures in women with osteoporosis > or = 80 years of age. Even in the oldest old, it is not too late to reduce fracture risk.