Effectiveness of screening for osteoporosis by bone density measurement for the prevention of fractures: a review of the evidence

To review evidence on the benefits of screening women and men for osteoporosis, a Pub Med search was performed in English papers published between 1990 and 2002. We used data from a cohort study to estimate risk of fracture from bone mineral density. Bone mineral density measured by dual X-ray absorptiometry (DXA) can predict bone fracture among elderly women, peri- and early post-menopausal women, and elderly men. It is recommended that all white women older than 65 years be screened routinely for osteoporosis. We suggest that Japanese elderly women should receive BMD measurements as a screening, but we have still issues to be solved including age from when the screening should be started, methods, and how to treat the women found to have osteoporosis at the screening. For peri- and postmenopausal women and elderly men, it might be beneficial to measure BMD as a screening and start treatment for those patients found to have osteoporosis. However, incidence of fractures for these people is lower than that for elderly women. One bone mass measurement can predict bone fracture risk for as long as over 10 years or more, but predictive ability of BMD decreases with time. Therefore, cost effectiveness needs to be reviewed to determine the benefits of screening among peri-menopausal women and men. Although bone assessment by quantitative ultra sound (QUS) method by ultrasound can also predict future fractures, only a relatively small number of longitudinal studies have been conducted in the Western countries, and there is no established evidence by means of longitudinal studies among Japanese. It is necessary in Japan to seek such evidence, however, since this method is widely used for an osteoporosis examinations.     

A review of the cost effectiveness of bisphosphonates in the treatment of post-menopausal osteoporosis in Switzerland

The economic burden associated with osteoporosis is considerable. As such, cost-effectiveness analyses are important contributors to the diagnostic and therapeutic decision-making process. The aim of this study was to review the cost effectiveness of treating post-menopausal osteoporosis with bisphosphonates and identify the key factors that influence the cost effectiveness of such treatment in the Swiss setting. A systematic search of databases (MEDLINE, EMBASE and the Cochrane Library) was conducted to identify published literature on the cost effectiveness of bisphosphonates in post-menopausal osteoporosis in the Swiss setting. Outcomes were compared with similar studies in Western European countries. Three cost-effectiveness studies of bisphosphonates in this patient population were identified; all were from a healthcare payer perspective. Outcomes showed that, relative to no treatment, treatment with oral bisphosphonates was predicted to be cost saving for most women aged ≥70 years with osteoporosis or at least one risk factor for fracture, and cost effective for women aged ≥75 years without prior fracture when used as a component of a population-based screen-and-treat programme. Results were most sensitive to changes in fracture risk, cost of fractures, cost of treatment, nursing home admissions and adherence with treatment. Swiss results were generally comparable to those in other European settings. Assuming similar clinical efficacy, lowering treatment cost (through the use of price-reduced brand-name or generic drugs) and/or improving adherence should both contribute to further improving the cost effectiveness of bisphosphonates in women with post-menopausal osteoporosis. Published evidence indicates that bisphosphonates are estimated to be similarly cost effective or cost saving in most treatment scenarios of post-menopausal osteoporosis in Switzerland and in neighbouring European countries.     

An Economic Evaluation of Quantitative Ultrasonometry as Pre-Screening Test for the Identification of Patients with Osteoporosis

Background

Screening for osteoporosis has been recommended to identify patients at high risk of fracture in order to provide preventative treatment. Given the limited availability of dual-energy x-ray absorptiometry (DXA) and health resources, quantitative ultrasonometry (QUS) has emerged as an attractive tool for the mass screening scenario. The objective of this study was to evaluate whether a screening strategy using QUS as a pre-screening tool for bone densitometry would be cost effective and, if so, at what cut-off thresholds.

Methods

Decision analytic models were used to compare the cost effectiveness and cost utility of several screening strategies: DXA measurement alone and pre-screening strategies that use different QUS index cut-off thresholds. For each strategy, and for hypothetical cohorts of women, we estimated the number of DXA scans required, the number of osteoporotic patients detected and missed, the total screening cost, and the incremental cost per patient detected. A validated Markov microsimulation model with a lifetime horizon and from a healthcare perspective was also computed in order to estimate the cost per quality-adjusted life-year (QALY) gained of the alternative screening strategies combined with 5 years of alendronate therapy for women who have osteoporosis (T-score -2.5 or less).

Results

The DXA strategy had the highest cost and the highest number of patients with osteoporosis detected. Prescreening strategies using QUS reduced the number of DXA scans per patient with osteoporosis detected and the total screening cost but they also missed patients with osteoporosis as the QUS index decreased. Pre-screening strategies using QUS T-scores of 0.0, ?0.5, ?2.0, and ?2.5 were dominated by extended dominance, as their incremental cost-effectiveness ratios (ICERs) and incremental cost-utility ratios (ICURs) were higher than that of the next more effective alternative. The cost-effectiveness and cost-utility frontiers included no screening, pre-screening using QUS T-scores of ?1.0 and ?1.5, and DXA measurement alone.

Conclusion

These results suggest that QUS may be useful as a pre-screening tool for bone densitometry given the limited availability of DXA and health resources, and that the QUS index T-scores of ?1.0 and ?1.5 are the most appropriate index.

     

The health economics of calcium and vitamin D3 for the prevention of osteoporotic hip fractures in Sweden

OBJECTIVE: The objective of this study was to examine the economics of administering calcium and vitamin D3 to post-menopausal women in Sweden. We focus primarily on the cost-effectiveness of treating older women for whom clear evidence of efficacy is available. We supplement this information, however, with estimates of the cost-effectiveness of treating certain high-risk groups of younger women, while acknowledging the greater uncertainty involved. METHODS: We developed a Markov model for analyzing the occurrence and timing of hip fractures, based almost entirely on peer-reviewed data from Sweden. In a 3-year randomized clinical trial, the combination of calcium and vitamin D3 was shown to reduce the risk of hip fractures by 27%. Costs for treating hip fractures were based on 1,080 women who were hospitalized in Stockholm. RESULTS: Treatment of 70-year-old women was cost saving at efficacy as low as two-thirds that seen in the clinical trials, and upwards. Even at modest rates of efficacy, treatment of the high-risk 50- and 60-year-old cohorts was generally cost-effective and in some cases even cost saving. Particularly cost-effective was treatment of women with identified osteoporosis or a maternal family history of hip fracture. CONCLUSION: Simulation results suggest a role for lifetime treatment of older women with calcium and vitamin D3 in Sweden. While there is more uncertainty underlying the treatment of younger women, our simulation results suggest that treatment may also be cost saving or at least cost-effective for many cohorts of high-risk 50- and particularly 60-year-old women, in particular those with osteoporosis or a maternal family history of hip fracture.     

Osteoprotegerin is associated with hip fracture incidence: the Tromso Study

BACKGROUND: Osteoprotegerin (OPG) is a cytokine essential for the regulation of bone resorption, but large longitudinal studies on its relationship to fracture risk in humans are lacking. In this population-based study of 2740 men and 2857 post-menopausal women, it was examined whether serum OPG was associated with hip fracture incidence. The participants were followed for 15 years. METHODS: Baseline measurements included height, weight and serum OPG, and information about lifestyle, prevalent diseases and use of medication. RESULTS: Men with OPG in the highest quartile were 2.79-fold [95% confidence interval (CI) 1.34-5.82] more likely to have a hip fracture during follow-up, compared with those with OPG in the lowest quartile (P-trend over OPG quartiles ≤0.001, after adjustments for age and other confounders). In women not using post-menopausal hormone therapy (HT), the risk of hip fracture was 1.64-fold higher (95% CI 0.94-2.86) in the highest quartile compared with the lowest OPG quartile (P-trend over OPG quartiles?=?0.05). No relationship was found in post-menopausal women using HT (P-trend over OPG quartiles?=?0.23). CONCLUSIONS: In men, OPG was positively associated with the incidence of hip fracture. In post-menopausal women not using HT a similar, but weaker, relationship was found.     

Osteoporosis: epidemiology and risk assessment

More than half of all women and about one-third of men will develop fractures related to osteoporosis. The consequences of fractures are often severe, and can lead to persistent declines in quality of life and increased mortality rates. Bone density should always be measured to quantitate the degree of fracture risk and provide a baseline value for future comparisons, regardless of whether other risk factors are present, because there are no symptoms other than fractures associated with disease progression, and because effective treatments for low bone density are available. Early detection and intervention is likely to be most effective because irreversible loss of bone structure has taken place by the time fractures begin to occur. Although the use of bone densitometry is on the rise, relatively few people are currently receiving treatment to prevent or reverse bone loss.     

Cost-Effectiveness of Using Clinical Risk Factors with and without DXA for Osteoporosis Screening in Postmenopausal Women

Background:  According to several guidelines, the assessment of postmenopausal fracture risk should be based on clinical risk factors (CRFs) and bone density. Because measurement of bone density by dual x-ray absorptiometry (DXA) is quite expensive, there has been increasing interest to estimate fracture risk by CRFs.
Objective:  The aim of this study was to determine the cost-effectiveness of osteoporosis screening of CRFs with and without DXA compared with no screening in postmenopausal women in Germany.
Methods:  A cost-utility analysis and a budget-impact analysis were performed from the perspective of the statutory health insurance. A Markov model simulated costs and benefits discounted at 3% over lifetime.
Results:  Cost-effectiveness of CRFs compared with no screening is €4607, €21,181, and €10,171 per quality-adjusted life-year (QALY) for 60-, 70-, and 80-year-old women, respectively. Cost-effectiveness of DXA plus CRFs compared with CRFs alone is €20,235 for 60-year-old women. In women above the age of 70, DXA plus CRFs dominates CRFs alone. DXA plus CRFs results in annual costs of €175 million, or 0.4% of the statutory health insurance's annual budget.
Conclusion:  Funders should be careful in adopting a strategy based on CRFs alone instead of DXA plus CRFs. Only if DXA is not available, assessing CRFs only is an acceptable option in predicting a woman's risk of fracture.     

Osteoporosis for the home care physician. Part 1: etiology and current diagnostic strategies

Osteoporosis affects over 20 million individuals in North America and is responsible for over 1.5 million fractures in the US. Although most cases of osteoporosis are primary, in 20% of older women and 40% of older men presenting with vertebral fractures, a secondary cause can be identified. The WHO based the diagnosis of postmenopausal osteoporosis on the presence of BMD T-score that is 2.5 standard deviations or greater below the mean for young women. The International Society of Clinical Densitometry defined male osteoporosis as BMD T-score of 2.5 or greater below the mean for young men. BMD assessment at the hip and spine by DXA is the standard procedure to assess bone density. Laboratory testing in patients with low BMD is performed to exclude other conditions that could cause low BMD such as multiple myeloma, endocrinopathies and osteomalacia. Bone turnover marker levels currently do not predict bone mass or fracture risk and are only weakly associated with changes in bone mass. Subsequently, they are of limited use in the clinical evaluation of bone density changes.     

The Fracture Risk Assessment Tool (FRAX®): applications in clinical practice

Osteoporosis is a serious health concern affecting millions of Americans, with many patients going undiagnosed and untreated. Fractures due to osteoporosis and fracture-related complications are the most clinically relevant and costly consequences of this disorder. The Fracture Risk Assessment Tool (FRAX?), released by the World Health Organization (WHO) in February 2008, is a major achievement in helping determine which patients may be candidates for pharmacological therapy for osteoporosis. This Web-based algorithm, which has been incorporated into some dual x-ray absorptiometry (DXA) reporting software, calculates the 10-year probability of major osteoporotic fracture (clinical vertebral, hip, forearm, or humerus) and the 10-year probability of hip fracture in men and women based on easily obtained clinical risk factors and bone mineral density (BMD) of the femoral neck (optional). The National Osteoporosis Foundation updated its U.S. guidelines in February 2008 to incorporate FRAX and recommends that all postmenopausal women and men aged ≥50 years with a hip or vertebral fracture, a T-score ≤-2.5 at the femoral neck or spine (excluding secondary causes), or low bone mass (T-score between -1.0 and -2.5) and a 10-year probability of hip fracture ≥3% or of major osteoporosis-related fracture ≥20% (based on FRAX) should be considered candidates for drug therapy. Despite its demonstrated clinical utility, FRAX has limitations and should not be used in all situations. Acceptance and clinical use of FRAX may help identify men and women at increased risk for osteoporotic fracture, but implementing the tool into clinical practice may be a challenge for busy physicians.     

Prevention and Treatment of Osteoporosis in Postmenopausal Women

Postmenopausal osteoporosis is characterized by an increased rate of bone turnover accompanied by a reduction in bone mineral density (BMD) that results in an increased risk of fracture, especially of the vertebrae, hip, or wrist. Alendronate (Fosamax®, Fosamax Once-Weekly®), an oral bisphosphonate that inhibits osteoclast-mediated bone resorption and modulates bone metabolism, is a first-line therapy for the management of postmenopausal women with, or at risk of developing, osteoporosis.Alendronate produces sustained increases in BMD and reductions in bone turnover from baseline, and reduces the risk of vertebral, hip, wrist, and other fractures in women with postmenopausal osteoporosis. It also prevents bone loss, and reduces the risk of radiographic or clinical vertebral fracture in postmenopausal osteopenia. Provided administration instructions are followed, alendronate is generally well tolerated. Adverse events are usually transient and are associated with the upper gastrointestinal tract (abdominal pain, nausea, acid regurgitation, dyspepsia); moreover, the incidence of these adverse events with alendronate was similar to those with placebo. More serious events (esophagitis, gastric or duodenal ulceration or bleeding) are uncommon. Once-weekly formulations are as effective and as well tolerated as once-daily alendronate in postmenopausal women.Pharmacoeconomic evaluations suggest that alendronate is a viable treatment option in postmenopausal osteoporosis. The reduction in fracture-related healthcare utilization seen with alendronate results in decreased direct costs, including inpatient or long-term care. Markov state-transition models suggest that this could at least partially offset costs incurred with alendronate therapy. Treatment of women with osteoporosis aged 65 years and older, and postmenopausal women with a previous osteoporotic fracture, are cost-effective strategies. Alendronate is also likely to increase quality-adjusted life-years in any postmenopausal women with osteoporosis.In conclusion, clinical and economic data support the use of alendronate in postmenopausal osteoporosis. It effectively reduces bone turnover, increases BMD, and reduces the risk of osteoporotic fracture in postmenopausal women with established osteoporosis, especially older women with a higher risk of fracture. Although its cost effectiveness in postmenopausal women with osteopenia is not clearly established, alendronate is clinically effective in these patients. In addition, it is generally well tolerated when taken as recommended. Consequently, alendronate should be considered a therapy of choice in the prevention and treatment of osteoporosis in postmenopausal women.     

Cost effectiveness of ultrasound and bone densitometry for osteoporosis screening in post-menopausal women

Background

According to a new German guideline, decisions about bisphosphonate treatment for post-menopausal women should be based on 10-year fracture risk, and bone density should be measured by dual x-ray absorptiometry (DXA). Recently, there has been growing interest in quantitative ultrasound (QUS) as a less expensive screening alternative.

Objective

To determine the cost effectiveness of osteoporosis screening with QUS as a pre-test for DXA and treatment with alendronate compared with (i) immediate access to DXA and (ii) no screening in women of the general population aged 50-90 years in Germany.

Methods

A cost-utility analysis and a budget impact analysis were performed from the perspective of the statutory health insurance (SHI). A Markov model with a 1-year cycle length was used to simulate costs and benefits (QALYs), discounted at 3% per annum, over a lifetime. The number of women correctly diagnosed by QUS and DXA as being above a 10-year risk of ≥30% was estimated for different age groups (50–60, 60–70, 70–80 and 80–90 years, respectively). The robustness of the results was tested by a probabilistic Monte Carlo simulation.

Results

Compared with no screening, the cost effectiveness of QUS plus DXA was found to be €3529, €9983, €4382 and €1987 per QALY for 50-, 60-, 70- and 80-year-old women, respectively (year 2006 values). This screening strategy results in annual costs of €96 million or 0.07% of the SHI’s annual budget. The cost effectiveness of DXA alone compared with DXA plus QUS is €5331, €60 804, €14943 and €3654 per QALY for 50-, 60-, 70- and 80-year-old women, respectively. DXA alone results in a higher number of QALYs in all age groups. The results were robust in the sensitivity analysis.

Conclusion

Compared with no screening, the cost effectiveness of QUS and DXA in sequence is very favourable in all age groups. However, direct access to DXA is also a cost-effective option, as it increases the number of QALYs at an acceptable cost compared with pre-testing by QUS (except for women aged 60–70 years). Therefore, QUS as a pre-test for DXA can be clearly recommended only in women aged 60–70 years. For the other age groups, the cost effectiveness of QUS as a pre-test depends on the global budget constraint and the accessibility of DXA.     

Surveillance for injuries and violence among older adults.

PROBLEM/CONDITION: Injuries and violence are major causes of disability and death among adults aged > or =65 years in the United States. Injuries impair older adults' quality of life and result in billions of dollars in health-care expenditures each year. REPORTING PERIOD: This report reviews 1987-1996 data regarding fall-related deaths, 1988-1996 data on hospitalizations for hip fracture, 1990-1997 data regarding motor vehicle-related injuries, 1990-1996 data on suicides, and 1987-1996 data on homicides. DESCRIPTION OF SYSTEMS: Data on fall-related deaths, suicides, and homicides are from the National Center for Health Statistics annual mortality data tapes for 1987-1996. Homicide data are supplemented with information from the Federal Bureau of Investigation's Supplemental Homicide Reports for 1987-1996. Data on hospitalizations for hip fracture are from the 1988-1996 National Hospital Discharge Surveys. Information regarding motor vehicle-related injuries for 1990-1997 is from the National Highway Traffic Safety Administration's Fatality Analysis Reporting System and General Estimates System. RESULTS: Rates of fall-related deaths for older adults increased sharply with advancing age and were consistently higher among men in all age categories. Men were 22% more likely than women to sustain fatal falls. A trend of increasing rates of fall-related deaths was observed from 1987 through 1996 in the United States, although rates were consistently lower for women throughout this period. Rates of hospitalizations for hip fracture differed by age and were higher for white women than for other groups. Rates increased with advancing age for both sexes but were consistently higher for women in all age categories. U.S. hospitalization rates for hip fracture increased for women from 1988 through 1996 while the rates for men remained stable. Rates of motor vehicle-related injuries increased slightly from 1990 through 1997, and marked variations in state-specific death rates were observed; in most states, older men had death rates approximately twice those for older women. Although suicide rates remain higher among older adults than among any other age group, rates of suicide among adults aged > or =65 years decreased 16% during the study period. Suicide rates among older adults varied by sex and age group. Homicide rates declined 36% among older adults. Homicide rates were highest for black men, followed by black women and white men; the homicide risk for blacks relative to whites decreased from 4.8 to 3.9 per 100,000 persons, indicating that the gap between rates for blacks and whites is closing. Half of the older homicide victims were killed by someone they knew. INTERPRETATION: The increase in rates of fall-related deaths and hip fracture hospitalizations from 1988 through 1996 might reflect a change in the proportion of adults aged > or =85 years compared with those aged 65-84 years - a change that results, in part, from reduced mortality from cardiovascular and other chronic diseases. Fall-related death rates might be higher among older men because they often have a higher prevalence of comorbid conditions than women of similar age. Racial differences in hospitalization rates might have some underlying biologic basis; the prevalence of osteoporosis, a condition that contributes to reduced bone mass and increased bone fragility, is greatest among older white women. Compared with whites aged > or =65 years, blacks of comparable ages have greater bone mass and are less likely to sustain fall-related hip fractures. Additional studies are needed to determine why rates of motor vehicle-related injury have increased slightly among older adults and why these rates vary by state. Declining rates of suicide among older adults might be related to changes in the effect or type of risk factors traditionally observed in this age group. Research is needed to identify reasons for variations in suicide rates among older persons. Homicides among olde     

The Added Value of SARC-F to Prescreening Using FRAX for Hip Fracture Prevention in Older Community Adults

Objectives

To examine the potential added value of a simple 5-item questionnaire for sarcopenia screening (SARC-F) to the Fracture Risk Assessment Tool (FRAX) for hip fracture risk prediction, in order to identify at-risk older adults for screening with dual-energy x-ray absorptiometry (DXA).

Pre-menopausal simple hysterectomy and post-menopausal female bone mineral density

This study aimed to evaluate the bone mineral density (BMD) of post-menopausal women with previous pre-menopausal hysterectomy including bilateral ovarian conservation compared to a group of non-hysterectomized women with natural menopause. Data from a cross-sectional study of 30 pre-menopausally hysterectomized women evaluated in the post-menopause were compared with 102 naturally post-menopausal women, analyzing their respective bone densitometry, measuring the femoral and lumbar spinal BMD. Multiple regression analysis of the 132 women showed that age and body mass index (BMI) were heavily associated with femoral and lumbar spinal BMD, BMI directly associated, and age inversely associated with BMD. In addition, 30 hysterectomized women were matched by age and BMI to the 30 non-hysterectomized women, and bone densitometry did not show significant differences in BMD. These findings suggest that pre-menopausal hysterectomy with bilateral ovarian conservation does not appear to cause an additional reduction in bone mass when evaluated in the post-menopausal phase.     

The Burden of Osteoporosis and the Case for Disease Management

Currently, osteoporosis, defined as low bone mineral density (BMD), affects 30% of postmenopausal women and 8% of men >50 years old in Western society and these percentages are likely to increase as our elderly population expands. Osteoporosis-related fractures increase with age and reductions in BMD, with the greatest increase in hip, followed by vertebral, and then wrist fractures. Osteoporosis is associated with significant mortality and for each 1 SD decrease in BMD there is a 1.5-fold increase in mortality risk. Following a hip fracture, 25–30% of patients will die within 3–6 months and in some populations hip fractures account for 1.5% of all deaths. Osteoporosis and related fractures are associated with significant morbidity, with loss of independence, psychological effects, and an overall decreased quality of life.The current financial cost of osteoporosis in the US is $US14 billion and in the UK just over £1 billion, and these costs will increase 3- to 8-fold over the next 50 years. Treatments are available that have been shown to significantly increase BMD, decrease bone turnover, and as a result decrease fracture incidence. For reductions in both vertebral and fracture, the evidence is strongest for the use of the bisphosphonates alendronate and risedronate; while for vertebral fracture, effective treatments include raloxifene, etidronate, calcitonin, and calcium plus vitamin D. Recent data suggest that hormone replacement therapy (HRT) can prevent hip and vertebral fractures, but long-term use, or commencement in elderly women of some continuous combined preparations, is no longer recommended.It has been recognized that bone turnover and bone quality contribute to fracture risk and, therefore, biochemical assessment of bone resorption and formation may increase the clinical and cost effectiveness of treatment. Using a conservative estimate of fracture reduction (35%) over a 5-year period, an intervention costing $US500 (£333) per year is cost effective when targeted to women with osteoporosis who are ≥65 years of age. It has been calculated that the lower the intervention cost and the higher the effectiveness of treatment the lower the age at which the treatment would be cost effective. The increasing healthcare burden and effective treatments make osteoporosis an excellent candidate for disease management programs.     

Osteoporosis assessment and treatment in older patients who have sustained a hip fracture

BACKGROUND AND AIMS: Currently fracture sufferers are not being assessed or treated for osteoporosis. Osteoporosis guidelines differ in their secondary prevention recommendations, with the Scottish Intercollegiate Guideline Network (SIGN) advocating bone densitometry in all fracture patients and anti-resorptive treatment only if evidence-based criteria are confirmed, but the National Institute of Clinical Excellence (NICE) technology appraisal recommends treatment for all older females without this bone densitometry confirmation. We aimed to determine the rate of referral for bone densitometry, the numbers achieving SIGN criteria for anti-resorptive therapy, and the rate of osteoporosis treatment in patients with hip fracture METHODS: A retrospective review of all patients older than 65 years who had sustained a hip fracture in Tayside between April 2003 and July 2005 was performed RESULTS: Only 8.6% of hip fracture patients underwent bone densitometry, of which 90.6% of females older than 75 years met SIGN criteria for anti-resorptive treatment. 74.3% of all patients referred for bone densitometry were treated with an anti-resorptive agent, compared to only to 12.7% of the large majority group who were not assessed for osteoporosis CONCLUSION: Osteoporosis investigation and therefore treatment remains sub-optimal in hip fracture patients. Almost all females, older than 75 years, with a hip fracture met evidence-based criteria for anti-resorptive treatment. NICE guidance, recommending anti-resorptive treatment without bone densitometry confirmation of reduced bone mineral density, should maybe be implemented for this specific group of patients in an attempt to increase osteoporosis treatment rates.     

The role of dietary calcium in bone health

Approximately 99% of body Ca is found in bone, where it serves a key structural role as a component of hydroxyapatite. Dietary requirements for Ca are determined by the needs for bone development and maintenance, which vary throughout the life stage, with greater needs during the periods of rapid growth in childhood and adolescence, during pregnancy and lactation, and in later life. There is considerable disagreement between expert groups on the daily Ca intake levels that should be recommended, reflecting the uncertainty in the data for establishing Ca requirements. Inadequate dietary Ca in early life impairs bone development, and Ca supplementation of the usual diet for periods of < or = 3 years has been shown to enhance bone mineral status in children and adolescents. However, it is unclear whether this benefit is long term, leading to the optimisation of peak bone mass in early adulthood. In later years inadequate dietary Ca accelerates bone loss and may contribute to osteoporosis. Ca supplementation of the usual diet in post-menopausal women and older men has been shown to reduce the rate of loss of bone mineral density at a number of sites over periods of 1-2 years. However, the extent to which this outcome reduces fracture risk needs to be determined. Even allowing for disagreements on recommended intakes, evidence indicates that dietary Ca intake is inadequate for maintenance of bone health in a substantial proportion of some population groups, particularly adolescent girls and older women.     

Development and internal validation of the male osteoporosis risk estimation score

PURPOSE We wanted to develop and validate a clinical prediction rule to identify men at risk for osteoporosis and subsequent hip fracture who might benefit from dual-energy x-ray absorptiometry (DXA).METHODS We used risk factor data from the National Health and Nutrition Examination Survey III to develop a best fitting multivariable logistic regression model in men aged 50 years and older randomized to either the development (n = 1,497) or validation (n = 1,498) cohorts. The best fitting model was transformed into a simplified scoring algorithm, the Male Osteoporosis Risk Estimation Score (MORES). We validated the MORES, comparing sensitivity, specificity, and area under the receiver operating characteristics (ROC) curve in the 2 cohorts and assessed clinical utility with an analysis of the number needed-to-screen (NNS) to prevent 1 additional hip fracture.RESULTS The MORES included 3 variables—age, weight, and history of chronic obstructive pulmonary disease—and showed excellent predictive validity in the validation cohort. A score of 6 or greater yielded an overall sensitivity of 0.93 (95% CI, 0.85–0.97), a specificity of 0.59 (95% CI, 0.56–0.62), and an area under the ROC curve of 0.832 (95% CI, 0.807–0.858). The overall NNS to prevent 1 additional hip fracture was 279 in a cohort of men representative of the US population.CONCLUSIONS Osteoporosis is a major predictor of hip fractures. Experts believe bisphosphonate treatment in men should yield results similar to that in women and reduce hip fracture rates associated with osteoporosis. In men aged 60 years and older, the MORES is a simple approach to identify men at risk for osteoporosis and refer them for confirmatory DXA scans.     

Calcium and protein in bone health

Dietary protein has several opposing effects on Ca balance and its net effect on bone is not well established. It has long been recognized that increasing protein intake increases urinary Ca excretion. More recently, it has been observed that increasing dietary protein raises the circulating level of insulin-like growth factor-1, a growth factor that promotes osteoblast formation and bone growth. Other effects of protein on the Ca economy have been suggested in some studies, but they are less well established. Several studies have examined associations between protein intake and bone loss and fracture rates. In the original Framingham cohort subjects with lower total and animal protein intakes had greater rates of bone loss from the femoral neck and spine than subjects consuming more protein. In another study higher total (and animal) protein intakes were associated with a reduced incidence of hip fractures in post-menopausal women. In contrast, a high animal:plant protein intake has been associated with greater bone loss from the femoral neck and a greater risk of hip fracture in older women. Higher total and higher animal protein intakes have also been associated with increased risk of forearm fracture in younger post-menopausal women. In a recent study it was found that increasing dietary protein was associated with a favourable (positive) change in bone mineral density of the femoral neck and total body in subjects taking supplemental calcium citrate malate with vitamin D, but not in those taking placebo. The possibility that Ca intake may influence the impact of dietary protein on the skeleton warrants further investigation.     

Preferred skeletal site for osteoporosis screening in high-risk populations

OBJECTIVES: The current World Health Organization (WHO) definition of osteoporosis, which is based on densitometry of lumbar and femoral regions, is extensively used for decision-making in clinical practice. Discordance in diagnosis of osteoporosis using this definition is a known phenomenon. The aim of this study was to evaluate the impact of such discordance and to assess the diagnostic value of using one skeletal site for screening purposes as opposed to the two sites required in the WHO criteria. STUDY DESIGN: Data was collected from 4188 individuals (3848 female); mean age=53.4 years (standard deviation 11.8) referred to a community-based outpatient osteoporosis testing centre in Tehran, Iran. METHODS: Dual-energy X-ray absorptiometry (DXA) was performed on L1-L4 lumbar spine and total hip for all cases. The DXA results were categorized according to WHO criteria. Sensitivity for each site was calculated as number of cases with T-score < -2.5 at that site divided by the total number of cases with T-score < -2.5 at any site. RESULTS: Prevalence of osteoporosis diagnosis using lumbar DXA, femoral DXA, and WHO criteria (either of the sites) were 24.7%, 12.4%, and 27.8%, respectively. Sensitivity of lumbar DXA for diagnosis of osteoporosis (88.9%) was significantly higher than femoral DXA (44.6%, P<0.001); but this difference became non-significant for men > or = 60 and women > or = 70 (P=0.615 and P=0.077, respectively). Agreement of the procedures in different sites (kappa) was 0.40 (0.37 to 0.43). When proximal femur was considered as the reference, positive likelihood ratios of lumbar DXA to detect cases were 4.7 and 2.0 in younger and older groups, respectively. CONCLUSIONS: Concerning the high rate of discordance and low agreement between DXA results, the data obtained from each anatomical site cannot predict the condition of the other site. However, if use of a single assessment is intended for screening programs, public health authorities can develop different strategies for different age groups of their population. We propose lumbar DXA for the younger group (men < 60 and women < 70) and femoral densitometry for the older.