By Heidi D. Nelson, MD, MPH; Elizabeth M. Haney, MD; Tracy Dana, MLS; Christina Bougatsos, BS; and Roger Chou, MD

Address correspondence to: Heidi D. Nelson, MD, MPH, Oregon Evidence-based Practice Center, Oregon Health & Science University, Mailcode BICC, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239-3098.

The information in this report is intended to help clinicians, employers, policymakers, and others make informed decisions about the provision of health care services. This report is intended as a reference and not as a substitute for clinical judgment.

This report may be used, in whole or in part, as the basis for the development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products may not be stated or implied.

This article was first published in Annals of Internal Medicine on July 6, 2010 (Annals of Internal Medicine 2010;153(2):1-14; www.annals.org). Select for copyright and source information.

Editor's Note: As part of the U.S. Preventive Services Task Force's (USPSTF) ongoing commitment to clarity about its work and methods, it has begun to invite public comment on all draft recommendation statements before publication of the final statements. Because of this new initiative, the recommendation on screening for osteoporosis does not appear with this accompanying background review. When the USPSTF's draft recommendation statement on screening for osteoporosis was published on July 6, 2010, the public was offered the opportunity to comment on the draft recommendation statement. The comment period for this recommendation is now closed. The USPSTF will consider submitted comments when it finalizes the recommendation for subsequent publication in Annals and posting on the USPSTF Web site at http://www.uspreventiveservicestaskforce.org/.

Background: This review updates evidence since the 2002 U.S. Preventive Services Task Force recommendation on osteoporosis screening.

Purpose: To determine the effectiveness and harms of osteoporosis screening in reducing fractures for men and postmenopausal women without known previous fractures; the performance of risk-assessment instruments and bone measurement tests in identifying persons with osteoporosis; optimal screening intervals; and the efficacy and harms of medications to reduce primary fractures.

Data Sources: Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews (through the fourth quarter of 2009), MEDLINE® (January 2001 to December 2009), reference lists, and Web of Science.

Study Selection: Randomized, controlled trials of screening or medications with fracture outcomes published in English; performance studies of validated risk-assessment instruments; and systematic reviews and population-based studies of bone measurement tests or medication harms.

Data Extraction: Data on patient populations, study design, analysis, follow-up, and results were abstracted, and study quality was rated by using established criteria.

Data Synthesis: Risk-assessment instruments are modest predictors of low bone density (area under the curve, 0.13 to 0.87; 14 instruments) and fractures (area under the curve, 0.48 to 0.89; 11 instruments); simple and complex instruments perform similarly. Dual-energy x-ray absorptiometry predicts fractures similarly for men and women; calcaneal quantitative ultrasonography also predicts fractures, but correlation with dual-energy x-ray absorptiometry is low. For postmenopausal women, bisphosphonates, parathyroid hormone, raloxifene, and estrogen reduce primary vertebral fractures. Trials are lacking for men. Bisphosphonates are not consistently associated with serious adverse events; raloxifene and estrogen increase thromboembolic events; and estrogen causes additional adverse events.

Limitation: Trials of screening with fracture outcomes, screening intervals, and medications to reduce primary fractures, particularly those enrolling men, are lacking.

Conclusion: Although methods to identify risk for osteoporotic fractures are available and medications to reduce fractures are effective, no trials directly evaluate screening effectiveness, harms, and intervals.

Primary Funding Source: Agency for Healthcare Research and Quality.

This systematic evidence review is an update for the U.S. Preventive Services Task Force (USPSTF) recommendation on screening for osteoporosis. In 2002, on the basis of results of a previous review^1,2, the USPSTF recommended bone density screening for women 65 years or older and for women aged 60 to 64 years at increased risk for osteoporotic fractures^3,4. They made no recommendations for or against screening postmenopausal women younger than 60 years or women aged 60 to 64 years without increased risk. Men were not considered in the previous recommendation.

Osteoporosis is a systemic skeletal condition characterized by low bone mass and microarchitectural deterioration of bone tissue that increases bone fragility and risk for fractures⁵. Osteoporosis may occur without a known cause or secondary to another condition. Osteoporosis is diagnosed in persons on the basis of presence of a fragility fracture or by bone mass measurement criteria. These criteria were developed by the World Health Organization from epidemiologic data that describe the normal distribution of bone mineral density (BMD) in a young healthy reference population ⁶. Osteoporosis is diagnosed when the BMD at the spine, hip, or wrist is 2.5 or more SDs below the reference mean (T-score of -2.5 or less), and low bone density or mass is diagnosed when BMD is from 1.0 to 2.5 SDs below the reference mean. Other important components of the condition, such as rate of bone loss and quality of bone, are not well characterized clinically.

Estimates indicate that as many as 50% of Americans older than 50 years will be at risk for osteoporotic fractures during their lifetimes⁵. This translates to 12 million persons with osteoporosis by 2012⁵. Specific prevalence rates depend on how bone density is measured and characteristics of the population. Rates for women are higher than those for men; rates vary by race, with the highest rates in white persons; and rates for all demographic groups increase with age^7-9. Older persons have much higher fracture rates than younger persons with the same bone density because of increasing risks from other factors, such as bone quality and tendency to fall¹⁰.

All types of fractures are associated with higher mortality rates^11-14. Men are more likely than women to die in the year after a hip fracture, with mortality rates for men estimated at up to 37.5%¹⁵. Fractures adversely affect function and quality of life, resulting in chronic pain, disability, and high costs⁵. Despite increased awareness of the magnitude and consequences of osteoporosis and recommendations for screening and treatment from several groups, osteoporosis is underdetected and inadequately treated in the United States^16,17. Reasons for this are unclear, although the differing recommendations for identifying candidates for testing and treatment, confusion in interpreting results of testing, and fragmentation of health care may contribute¹⁸.

This update focuses on new studies and evidence gaps that were unresolved at the time of the 2002 USPSTF recommendation. These include the effectiveness and harms of osteoporosis screening in reducing fractures for men as well as postmenopausal women without known previous fractures; the performance of risk-assessment instruments and bone measurement tests in identifying persons with osteoporosis; optimal screening intervals; and efficacy and harms of medications to reduce primary fractures in a screening-detected population.

The USPSTF and the Agency for Healthcare Research and Quality (AHRQ) developed key questions for this review. Investigators created an analytic framework, incorporating the key questions and outlining the patient populations, interventions, outcomes, and harms of the screening process (Appendix Figure 1). The target populations include postmenopausal women and men older than 50 years without known previous osteoporosis-related fragility fractures or secondary causes of osteoporosis. Harms of screening include consequences of false-positive and false-negative tests, patient anxiety and other psychosocial responses, unnecessary treatment, as well as adverse outcomes from medications.

Data Sources and Searches

We searched the Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews (through the fourth quarter of 2009) and MEDLINE® (January 2001 to December 2009) for relevant studies and systematic reviews. A technical report¹⁹ describes search strategies and additional details. We also conducted secondary referencing by manually reviewing reference lists of key papers and searching citations by using Web of Science²⁰ (Appendix Figure 2).

Study Selection

We selected studies on the basis of inclusion and exclusion criteria developed for each key question¹⁹. We included randomized, controlled trials (RCTs) with fracture or fracture-related morbidity and mortality outcomes to determine the effectiveness of osteoporosis screening and studies of any design to determine harms from screening.

To determine the accuracy and clinical applicability of risk-assessment instruments, we included studies of externally validated instruments that reported performance characteristics. Instruments were included if they were derived from an initial population and then tested in a separate population; derived from computer modeling, consensus, or another study and then tested in a novel population; or derived from any source and tested against T-scores or actual fracture rates in a population. We did not include internally validated measures (imputation methods or cross-validation). To determine the performance of bone measurement tests in predicting fractures, we limited studies to existing systematic reviews and technology assessments of procedures currently used in U.S. practice and large population-based studies relevant to primary care settings. We included any studies providing data about screening intervals.

To evaluate the efficacy and harms of medications to reduce fractures in a screening-detected population, we included RCTs and meta-analyses of RCTs that reported fracture and fracture-related outcomes and adverse effects for medications used in the United States. Outcomes included specific types of fractures; fracture-related morbidity, including loss of function, pain, quality of life, and other reported health outcomes; and fracture-related mortality. We excluded nondrug therapies because they are addressed in other reviews for the USPSTF (for example, calcium, vitamin D, exercise, and fall prevention) and combination therapies. We focused on trials that enrolled patients without known previous osteoporosis-related fragility fractures, such as vertebral compression or hip fractures, and without known secondary causes of osteoporosis because this population is most relevant to screening. We included trials that met 1 of the following 3 criteria. First, the trial excluded persons with previous vertebral or other presumably osteoporotic fractures. Second, the trial permitted persons with previous osteoporotic fractures, but the overall proportion of participants with fractures was less than 20%, or the trial reported results separately for participants with and without previous fractures. We considered trials meeting this criterion to be applicable to primary prevention based on epidemiologic data²¹. Third, the trial did not report the proportion of participants with previous osteoporotic fractures, but inclusion criteria did not select persons on the basis of presence of a previous fracture, and mean BMD T-scores were -3.0 or more. This threshold was selected because placebo-controlled trials that enrolled more than 20% of women with previous fractures reported mean baseline BMD T-scores less than -3.0^22-25.

We determined harms from good- and fair-quality systematic reviews that pooled primary and secondary prevention trials after verifying data abstraction and statistical analyses and large controlled observational studies. For osteonecrosis of the jaw, we included systematic reviews summarizing evidence from case reports and series.

Data Abstraction and Quality Assessment

Details about the patient population, study design, analysis, follow-up, and results were abstracted. By using predefined criteria developed by the USPSTF²⁶, 2 investigators rated the quality of studies (good, fair, or poor) and resolved discrepancies by consensus. We assessed the overall strength of the body of evidence for each key question (good, fair, or poor) by using methods developed by the USPSTF on the basis of the number, quality, and size of studies; consistency of results between studies; and directness of evidence²⁶.

Data Synthesis and Analysis

We pooled results of primary prevention trials of bisphosphonates for various fracture outcomes (vertebral, nonvertebral, hip, wrist, and ankle) by using the random-effects Mantel-Haenszel method in Review Manager (RevMan), Version 5.0 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). We chose the random-effects model because of differences in study participant characteristics, such as baseline BMD, previous fractures, and risk factors for osteoporosis. Results were also stratified by type of bisphosphonate if sufficient data for pooling were available. For trials that evaluated several doses, we focused on outcomes for doses similar to those currently recommended in the package inserts approved by the U.S. Food and Drug Administration (FDA).

Several trials included in the meta-analyses reported few, rare, or 0 fracture events. The primary analyses excluded trials with 0 events in both groups, resulting in loss of data, and applied a constant continuity correction of 0.5 for trials with 0 events in 1 group, potentially biasing inferences^27,28. In addition, the random-effects Mantel-Haenszel method we used may be unsuitable when events are rare²⁷. We therefore conducted sensitivity analyses to determine the effects of alternate pooling methods on estimates by using the Peto odds ratio (OR), fixed-effects Mantel-Haenszel method with an alternative continuity correction, and the pooled arcsine difference^27-29. The Appendix provides details about the methods and results of these analyses, as well as other sensitivity analyses.

Role of the Funding Source

The AHRQ funded this work, developed key questions in conjunction with USPSTF members, and assisted with internal and external review of the draft, but had no additional role in the design, conduct, or reporting of the review. External experts not affiliated with the USPSTF reviewed the draft manuscript.

Effectiveness and Harms of Osteoporosis Screening in Reducing Fractures, Morbidity, and Mortality (Key Questions 1 and 4)

We identified no trials of the effectiveness of screening and no studies evaluating potential harms from screening. Adverse outcomes from medications are addressed by key question 6.

Performance of Risk-Assessment Instruments to Stratify Individuals Into Risk Categories (Key Question 2)

Thirty-three studies evaluated 21 externally validated clinical risk-assessment instruments and reported performance estimates of the area under the curve (AUC) for the receiver-operating characteristic curve predicting either bone density or fractures^30-62. Eight instruments were tested with men^{30, 36, 45-47, 57, 60, 61}. Instruments include from 1^{33, 34, 37, 38, 48} to more than 15^{32, 45} variables, although most include age, weight or body mass index, and previous fracture. Family history of fractures, smoking status, and estrogen use are also commonly included. Important methodological limitations of studies include nonrepresentative samples, cross-sectional rather than prospective data collection, inconsistent performance of the reference standard, and differences in performance measures across studies. The technical report¹⁹ describes additional studies of instruments that were internally validated or not validated or did not report AUC estimates, along with studies that combined clinical risk factors with peripheral dual-energy x-ray absorptiometry (DEXA) or quantitative ultrasonography (QUS) measures.

Twenty-three studies of 14 instruments to predict low BMD (T-score of -2.5 or less) reported AUC estimates ranging from 0.13 to 0.87, with most between 0.60 and 0.8^{30, 32-35, 37, 38, 42-44, 47-53, 55, 56, 58-61} (Table 1). Although some instruments had high AUC estimates in selected studies, none demonstrated high estimates in several studies. Instruments with fewer risk factors often did as well or better than those with more. For example, the Osteoporosis Self-assessment Screening Tool (OST) includes only age and weight, has similar AUC estimates as other more complicated instruments, and has been validated in both men^{30, 47, 61} and women^{37, 43, 44, 48, 53, 55}. Eleven studies of 11 instruments to predict fractures reported AUC estimates from 0.48 to 0.89^{31, 36, 39-41, 45, 46, 52, 54, 57, 62} (Table 1). Four studies included both men and women^36,45,46,57; all others included only women.

The World Health Organization and National Osteoporosis Foundation recently developed the FRAX instrument to predict individual fracture risks^{46, 63}. FRAX estimates adjust for nationality and include femoral neck BMD if available and age, sex, height, body mass index, previous fracture, family history of fracture, glucocorticoid use, current smoking status, daily alcohol use of 3 units or more, rheumatoid arthritis, and other secondary causes of osteoporosis. FRAX was derived from combined data from 46,340 persons from 9 different cohorts and subsequently tested in 230,486 persons from 11 validation cohorts⁴⁶. Seven derivation cohorts and 1 validation cohort included men. Although the risk calculator is available on a Web site (www.shef.ac.uk/FRAX/), the source code is not accessible. The AUC estimates for FRAX ranged from 0.54 to 0.78 for osteoporotic fractures^40,46,57 and 0.65 to 0.81 for hip fractures⁴⁶ (Table 1). Three studies compared FRAX with simple models, such as age and BMD or age and fracture history, and found that simple models did as well as FRAX in predicting hip and other clinical fractures^{40, 64} and vertebral fractures³⁹. We did not identify studies that prospectively tested FRAX in clinic populations or determined its effectiveness in selecting patients for therapy.

Performance of DEXA in Predicting Fractures in Men (Key Question 3a)

Two good-quality, prospective cohort studies evaluated the performance of DEXA in predicting fractures in men and compared results of men with those of women^65-67. The Rotterdam Study compared 4,731 women and 3,075 men 55 years or older from the same community at the same time^{65, 66}. Nonvertebral fractures were determined 6 to 7 years after baseline BMD from fracture reports, and vertebral fractures were determined from follow-up radiography by using morphometric criteria. For each sex-specific SD decrease in femoral neck BMD, the hazard ratio for all nonvertebral fractures was 1.4 (95% CI, 1.2 to 1.6) for men and 1.5 (CI, 1.4 to 1.6) for women and were similar for several site-specific fractures^65,66. The hazard ratio for vertebral fractures was 1.8 (CI, 1.3 to 2.4) for men and 1.9 (CI, 1.6 to 2.4) for women.

A study of BMD and risk for hip and nonvertebral fractures compared men enrolled in MrOS (Osteoporotic Fractures in Men Study) with women in SOF (Study of Osteoporotic Fractures) and reported similar results⁶⁷. However, in this study, DEXA of the femoral neck was associated with a higher relative risk for hip fracture in men (3.68 [CI, 2.68 to 5.05]) than in women (2.48 [CI, 2.09 to 2.95]). Additional studies are consistent with findings from the Rotterdam Study and MrOS^68-70. Variations in estimates may be due to the different patient populations, study designs, and other factors.

Performance of Peripheral Bone Measurement Tests in Predicting Fractures (Key Question 3b)

Several peripheral bone measurement tests have been developed, although clinical practice and recent research focus on QUS of the calcaneous. For postmenopausal women, 7 studies of DEXA and QUS report similar AUC estimates and risk ratios for fracture outcomes in general, although results vary across studies^71-77 (Appendix Table 1). For all fractures combined, AUC estimates range from 0.59 to 0.66, and risk ratios range from 1.81 to 2.16 for DEXA of the femoral neck. For QUS, AUC estimates are approximately 0.60, and risk ratios range from 1.26 to 2.25. Similar results were found in 5 studies of men^{68-70, 73, 78}  (Appendix Table 1). For hip fractures specifically, DEXA of the femoral neck is associated with higher risk ratios than QUS for men and women in most studies ^{70, 72}.

Screening Intervals (Key Question 3c)

In a large, good-quality, prospective cohort study (SOF) of 4,124 women 65 years or older, repeated BMD measurement up to 8 years after an initial measurement did not result in statistically significant differences in AUC and risk ratio estimates for nonvertebral, hip, or vertebral fractures⁷⁹. No studies of screening intervals have been conducted in men or other groups of women.

Efficacy of Medications for Reducing Osteoporosis-Related Fractures (Key Question 5)

Primary Prevention Trials in Postmenopausal Women

Bisphosphonates. Fifteen placebo-controlled RCTs of bisphosphonates met inclusion criteria^{25, 80-93}  (Appendix Table 2). The FIT (Fracture Intervention Trial) met criteria for good quality⁸². Of 13 trials rated as fair quality, 8 lacked information on randomization, allocation concealment, or outcomes blinding^{25,84,86,89-93}; 5 trials did not report intention-to-treat analysis or blinding of providers^{80, 81, 85, 87, 88}. One poor-quality trial did not report blinding, intention-to-treat analysis, or attrition⁸³.

In 11 trials, mean baseline femoral neck BMD T-scores were -1.0 to -2.5^{80-84, 87-90, 92, 93}; 1 trial enrolled women with T-scores less than -2.5²⁵; and 3 trials enrolled women with T-scores greater than -1.0^{85, 86, 91}. Five trials excluded or did not enroll women with previous vertebral fractures ^{80-82, 84, 92}; 2 trials enrolled more than 20% of participants with previous vertebral fractures but reported results in the subgroup of women without previous fractures^{25, 87}; and the remainder did not report the proportion of women with previous fractures. Only FIT—the large, 4-year trial of alendronate—was designed to evaluate fractures as primary outcomes⁸².

Bisphosphonates reduced vertebral fractures compared with placebo (relative risk [RR], 0.66 [CI, 0.50 to 0.89]; 7 trials)^{82, 83, 85, 87-89, 91} (Table 2). Results based on alternative methods for pooling were nearly identical (Appendix Table 3). Including all trials, the absolute risk for vertebral fracture was 1.9% for bisphosphonates versus 3.1% for placebo. Subgroup analyses of individual bisphosphonates were limited by few fractures (range, 0 to 20 events) or drugs other than alendronate. Results were similar in a sensitivity analysis based on a broader definition for primary prevention that added 6 trials (≤40% of participants with previous vertebral fractures or baseline T-scores less than -3.0)^{22, 24, 87, 101-103}.

For total nonvertebral fractures, a pooled analysis of trials indicated no statistically significant effects for bisphosphonates compared with placebo (RR, 0.83 [CI, 0.64 to 1.08]; 9 trials) ^{82, 85, 86, 88-93} (Table 2). Differences were also not significant for alendronate. Subgroup analyses of other bisphosphonates were limited by few fractures (range, 5 to 18 events). Results for bisphosphonates were statistically significant when estimated using alternative pooling methods (Peto OR, 0.84 [CI, 0.72 to 0.98); fixed-effects Mantel-Haenszel with inverse sample size continuity correction RR, 0.86 [CI, 0.74 to 0.99]) (Appendix Table 3) A sensitivity analysis based on a broader definition for primary prevention described earlier was also statistically significant (RR, 0.82 [CI, 0.69 to 0.96]; 14 trials)^{22, 24, 82, 85-89, 91-93, 101-103}. Results for hip, wrist, or ankle fractures were not statistically significant (Table 2) but were limited by few fractures. For all analyses, estimates that included or excluded trials with 0 events were nearly identical, suggesting that including these trials would have little effect on results.

We could not adequately assess whether estimates of efficacy varied in women according to their mean baseline BMD because only FIT stratified results⁸². In FIT, for women with baseline femoral neck T-scores less than -2.5, alendronate reduced all types of fractures combined (RR, 0.64 [CI, 0.50 to 0.82]) and vertebral (RR, 0.50 [CI, 0.31 to 0.82)] and hip (0.44 [CI, 0.18 to 0.97]) fractures specifically. For women with T-scores from -1.6 to -2.0 or -2.0 to -2.5, we found nonstatistically significant trends toward reduced vertebral fractures but no effects on all types of fractures combined.

Parathyroid Hormone. A trial of parathyroid hormone evaluated fracture outcomes after 18 months in postmenopausal women with a BMD T-score less than -3.0 and no prevalent vertebral fractures (81% of enrollees) or a T-score less than -2.5 and 1 to 4 prevalent fractures (19%) ⁹⁴. The trial was considered fair quality because it did not describe blinding of outcomes. In women without previous fractures, parathyroid hormone reduced new vertebral fractures from 2.1% to 0.7% (RR, 0.32 [CI, 0.14 to 0.75]). Among all women, no difference in nonvertebral fractures was found (Table 2).

Raloxifene. The MORE (Multiple Outcomes of Raloxifene) trial included women with BMD T-scores less than -2.5 with or without previous vertebral fractures^{96, 98, 104}. The RUTH (Raloxifene Use for the Heart) trial was designed primarily to determine the effects of raloxifene on coronary events and invasive breast cancer, and fractures were secondary outcomes ⁹⁷. In a pooled analysis of both trials, raloxifene reduced vertebral (RR, 0.61 [CI, 0.54 to 0.69]) but not nonvertebral (RR, 0.97 [CI, 0.87 to 1.09]) fractures¹⁰⁵ (Table 2). In MORE, risk for vertebral fractures was reduced for women with or without previous vertebral fractures ^{96, 104}.

Estrogen. The WHI (Women's Health Initiative) is the largest prevention trial of estrogen (conjugated equine estrogen) with and without progestin (medroxyprogesterone acetate) that reports fracture outcomes in postmenopausal women. Both trials reported reduced clinical vertebral, hip, and all fractures combined compared with placebo^99,100 (Table 2). However, results of both trials were not statistically significant for selective sites, such as the hip, when CIs were adjusted.

Primary Prevention Trials in Men>

The only primary prevention trial for men evaluated the effects of parathyroid hormone in men with osteoporosis (baseline BMD lumbar spine T-scores, -2.0 to -2.4) and met criteria for good quality⁹⁵. Results indicated a trend toward reduced vertebral (RR, 0.49 [CI, 0.22 to 1.09]) and nonvertebral (RR, 0.51 [CI, 0.10 to 2.48]) fractures with parathyroid hormone, but fractures were few and results did not reach statistical significance^95,106.

Harms Associated With Medications for Osteoporosis and Low Bone Density (Key Question 6)

Bisphosphonates

Although case reports of serious upper gastrointestinal adverse events have been reported with all bisphosphonates, systematic reviews and individual trials found no differences with placebo in rates of serious gastrointestinal adverse events^107,108 or withdrawals^109-116 (Appendix Table 4) The FDA recently issued a report that summarized 54 cases of esophageal adenocarcinoma associated with bisphosphonates¹¹⁷.

Evidence on the risk for atrial fibrillation with bisphosphonates is mixed^{112, 113, 118-121}. The FDA issued an interim report of an ongoing review based on data from nearly 20,000 patients treated with bisphosphonates in placebo-controlled trials¹²². Results indicated no clear association between bisphosphonate exposure and the rate of serious or nonserious atrial fibrillation.

Case reports of severe musculoskeletal pain that may be reversible after discontinuing the medication have been reported with all bisphosphonates. Zoledronic acid was associated with increased musculoskeletal events in a systematic review of trials¹²³. Case reports of osteonecrosis of the jaw are primarily from patients with cancer who receive intravenous doses of bisphosphonates that are higher than doses used for osteoporosis treatment or prevention¹²⁴. Case reports of atypical, low-energy fractures of the femoral diaphysis in long-term users of alendronate have also been reported, but the incidence is unknown^125-127.

Calcitonin and Parathyroid Hormone

Evidence of harms is limited by few trials and inconsistent reporting of adverse events. Calcitonin does not increase risk for the acute coronary syndrome; and calcitonin and parathyroid hormone do not increase risk for cancer or increase mild gastrointestinal events¹²³.

Raloxifene

Raloxifene increases risk for thromboembolic events but not for coronary heart disease, stroke, or endometrial cancer^97,128,105. It can cause hot flashes, leg cramps, and peripheral edema^{96, 97, 104}. Raloxifene also reduces risk for invasive breast cancer in women without preexisting breast cancer^97,105.

Estrogen

Both estrogen with progestin and estrogen alone increase thromboembolic events^129,130 and strokes ^{100, 131}. Estrogen with progestin increases risk for coronary heart disease events¹³² and breast cancer¹³³, does not increase risk for endometrial cancer¹³⁴, and reduces risk for colon cancer¹³⁵. Estrogen alone did not affect these outcomes in the WHI^{100, 136, 137}.

Table 3 summarizes the evidence reviewed for this update, and an outcomes table providing an illustration of the clinical application of the evidence is described in the Appendix and Appendix Table 5 (Also Appendix Figures 3 and 4). No RCTs evaluated the overarching questions of the effectiveness and harms of screening for osteoporosis in reducing fractures and fracture-related outcomes for postmenopausal women and men. Therefore, no direct evidence that screening improves outcomes is available. Support for population screening would be based on evidence that individual risk for fracture can be estimated and fractures can be significantly reduced for persons at risk.

Although many different risk-assessment instruments have been developed, most include similar variables, such as age and weight. Studies that report AUC estimates for validated instruments demonstrate that they are modest predictors of low bone density or fracture, and simpler models perform as well as more complex ones, such as FRAX. No studies determined the effectiveness of these instruments in improving fracture outcomes.

Data from large population-based cohorts indicate that the predictive performance of DEXA is similar for men and women. Calcaneal QUS using various types of devices can predict fractures of the femoral neck, hip, or spine in men and women, although variation exists across studies. Quantitative ultrasonography has low correlation with DEXA, and it is not clear how QUS can be used to select persons for medications that were proven efficacious on the basis of DEXA criteria. Data are lacking to determine how frequently to obtain bone measurements, although 1 study indicated no advantage to repeated measures that were 8 years apart⁷⁹.

No trials of medications report effects on fracture-related morbidity and mortality. For postmenopausal women, bisphosphonates, parathyroid hormone, raloxifene, and estrogen reduce primary vertebral fractures. Bisphosphonates significantly reduce nonvertebral fractures in sensitivity analyses that used alternative pooling methods or broadened our definition of primary prevention—consistent with meta-analyses of secondary prevention trials of alendronate and risedronate^109,111. Estrogen also reduces nonvertebral fractures in trials when using unadjusted estimates, but results are not statistically significant when estimates are adjusted. In the only primary prevention trial that stratified results according to baseline BMD, benefits were observed only in patients with T-scores of -2.5 or less⁸². For men, no primary prevention trials of bisphosphonates exist, and results from a single trial of parathyroid hormone did not reach statistical significance.

Trials and safety reviews have not supported consistent associations with serious upper gastrointestinal adverse events, atrial fibrillation, or osteonecrosis of the jaw in otherwise healthy patients taking bisphosphonates for fracture prevention. The FDA has recently highlighted case reports of esophageal cancer and severe musculoskeletal pain. An analysis of data from 3 trials published after our searches found no association between bisphosphonate use and atypical fractures of the subtrochanteric or diaphyseal femur, with an event rate of 2.3 per 10,000 patient-years¹³⁸. Evidence on harms associated with calcitonin and parathyroid hormone for treatment of osteoporosis is limited. Raloxifene and estrogen with and without progestin increase thromboembolic events; estrogen with and without progestin increases stroke; and estrogen with progestin increases coronary heart disease among older users and breast cancer.

Osteoporotic fractures result from several factors, and this review is limited by its focus on only some of them. Consideration of vision, physical function, risk for falls, and secondary causes of osteoporosis, for example, is also important in reducing fractures. However, these conditions are beyond the scope of this review.

Available evidence is also limited. Trials of medications vary in size, duration, quality, and applicability and have few fracture outcomes. Primary prevention trials and trials that enroll men or persons with low BMD (that is, baseline BMD T-scores from -1.0 to -2.5) are lacking. Applying the results of clinical trials to patient care is especially difficult when selection criteria are rigid and study participants do not represent the community population. This is particularly true in older populations, in which comorbid conditions and use of several medications are common and would disqualify patients from enrolling in most trials.

Osteoporosis and osteoporosis-related fractures are common in aging men and women in the United States. Fractures cause premature mortality, loss of independence and function, reduced quality of life, and substantial financial costs. Although methods to identify persons at risk for osteoporotic fractures are available and medications to reduce fractures are effective, no trials directly evaluate screening effectiveness, harms, and intervals.

Source: Nelson HD, Haney EM, Dana T, Bougatsos C, Chou R. Screening for osteoporosis: an update for the U.S. Preventive Services Task Force. Ann Intern Med 2010;153(2):1-14.

Disclaimer: The findings and conclusions in this document are those of the authors, who are responsible for its content, and do not necessarily represent the views of the AHRQ. No statement in this report should be construed as an official position of AHRQ or of the U.S. Department of Health and Human Services.

Acknowledgment: The authors acknowledge the contributions of AHRQ Project Officer Kenneth Lin, MD, and USPSTF leads Rosanne Leipzig, MD, PhD; Diana Petitti, MD, MPH; and George Sawaya, MD. Rochelle Fu, PhD, conducted statistical sensitivity analyses; Andrew Hamilton, MLS, MS, created the literature searches; and Michelle Pappas, BA, provided administrative assistance at the Oregon Evidence-based Practice Center at the Oregon Health & Science University.

Grant Support: This manuscript is based on research conducted by the Oregon Evidence-based Practice Center under contract to the AHRQ (contract 290-02-0024). Dr. Haney was supported by a career development award from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (K23 AR051926).

ABONE = age, body size, no estrogen; ADL = activities of daily living; AUC = area under the curve; BMD = bone mineral density; BMI= body mass index; COPD = chronic obstructive pulmonary disease; DOEScore = Dubbo Osteoporosis Epidemiology Study; EPESE = Established Populations for the Epidemiologic Study of the Elderly; MORES = male osteoporosis risk estimation score; NOF = National Osteoporosis Foundation; OPERA = osteoporosis prescreening risk assessment; ORAI = osteoporosis risk assessment instrument; OSIRIS = osteoporosis index of risk; OST = Osteoporosis Self-assessment Tool; SCORE = simple calculated osteoporosis risk estimation; SOF = Study of Osteoporotic Fractures; SOFSURF = Study of Osteoporosis Fractures—Study Utilizing Risk Factors; WHI = Women's Health Initiative.
* Includes studies of externally validated instruments reporting performance measures with AUC estimates.
† Where provided or calculated for individual study results.
‡ BMD T-score of -2.5 or less.
§ Includes both derivation and validation cohorts.
ǁ Additional variables include first-degree relative who had a hip fracture; previous fracture at age >50 y; no walking for exercise; uses arms to rise from seated position; current use of benzodiazepines, anticonvulsants, or corticosteroids; resting pulse >80 beats/min; on feet <4 h/d; dementia diagnosis; not using menopausal hormone therapy; height ≥5 ft, 7 in, at age 25 y; and race other than black.
¶ Variables used for calculating QFracture score for women but not for men.

Table 2 (continued)

RR = risk ratio.
* Results for postmenopausal women, unless otherwise indicated.
† Data presented with nominal CIs; adjusted CI for hip (0.41-1.10) and not provided for other sites.
‡Clinical vertebral fractures.
§ Data presented with nominal CIs; adjusted CIs include vertebral (0.34 -1.13) and hip (0.33-1.11).

AUC = area under the curve; BMD = bone mineral density; CHD = coronary heart disease; DEXA = dual-energy x-ray absorptiometry; GI = gastrointestinal; KQ = key question; PTH = parathyroid hormone; QUS = quantitative ultrasonography; RCT = randomized, controlled trial.

AUC = area under the curve; BMD = bone mineral density; BUA = broadband ultrasound attenuation; DEXA = dual-energy x-ray absorptiometry; QUI = quantitative ultrasound index (combines BUA and SOS); QUS = quantitative ultrasonography measured at the calcaneus in all studies; RR = risk ratio; SOS = speed of sound; SXA = single x-ray absorptiometry; UBPI = ultrasound bone profile index.
* For studies reporting more than 1 type of fracture, results for the first type are provided first, then results for the second type.
† Adapted from the Canadian Agency for Drugs and Technologies in Health Technology Report¹⁴⁰. Data from references 71 and 72 included for completeness.
‡ Per SD reduction in BMD or QUS measure, adjusted for age, weight, and clinic center.
§ Per SD reduction in BMD or QUS measure, adjusted for age and clinic.
^a Adjusted for years of menopause, weight, height, and body mass index.
^b Per SD reduction in BMD or QUS measure.
** Per SD reduction in QUS measure, adjusted for age, previous fracture, smoking status, weight, and height.
†† Per SD reduction in QUS measure, adjusted for age, weight, calcium intake, current smoking status, regular walking outside, bedridden periods >2 mo.

aCI = adjusted CI; BMD = bone mineral density; CEE = conjugated equine estrogen; FIT = Fracture Intervention Trial; MORE = Multiple Outcomes of Raloxifene Evaluation; MPA = medroxyprogesterone acetate; nCI = nominal CI; NR = not reported; PTH = parathyroid hormone; RR = relative risk; RUTH = Raloxifene Use for the Heart; WHI = Women's Health Initiative.
* BMD T-scores for bisphosphonate trials are based on femoral neck measurements and calculated by using the FRAX patch instrument, unless stated otherwise.
† Clinical vertebral fractures only.
‡ Per SD reduction in BMD or QUS measure, adjusted for age, weight, and clinic center.
§ Subgroup of women with no previous vertebral compression fractures.

DVT = deep venous thrombosis; E-alone = estrogen without concomitant use of progestin; E + P = estrogen and concomitant use of progestin; FDA = U.S. Food and Drug Administration; FIT = Fracture Intervention Trial; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly (HORIZON) Pivotal Fracture Trial; PE = pulmonary embolism; RR = risk ratio; WHI = Women's Health Initiative.
† Adjusted CI, 0.97-1.60.
‡ Adjusted CI, 0.97-1.99.

RR = risk ratio.
* Assumptions based on population estimates and results of the Fracture Intervention Trial for women with T-score of -2.5 or less.
† From reference 139.
‡ From results of the Fracture Intervention Trail for women with a BMD T-score of the femoral neck of -2.5 or less⁸². Event rates have been recalculated for 5 y.

KQ = key question.

KQ = key question; USPSTF = U.S. Preventive Services Task Force.

*Cochrane databases include the Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews.
† Identified from reference lists and suggested by experts.
‡ Some abstracts and articles were considered for more than 1 KQ.
§ Additional articles are described in the technical report)¹⁹.

Major osteoporotic fractures include hip, clinical vertebral, proximal humerus, and distal forearm. Highlighted risks equal or exceed the reference case (woman aged 65 years with no risk factors: 9.3% for osteoporotic fracture; 1.2% for hip fracture). BMI = body mass index.
* Normal BMI = 25.0 kg/m² based on average height of 163 cm (64.17 in) and weight of 66.5 kg (146.61 lb). Low BMI = 21.2 kg/m² based on average height of 163 cm (64.17 in) and weight of 56.7 kg (125 lb).
† Daily alcohol use of 3 or more units/d (approximately 3 oz each).