Use Of Bone Mineral Density Measurements Research Articles

BFH-OSTM, a new predictive screening tool for identifying osteoporosis in elderly Han Chinese males.

PurposeTo develop and validate a new clinical screening tool to identify primary osteoporosis by dual-energy X-ray absorptiometry (DXA) in two elderly Han Chinese male populations.MethodsA cross-sectional study was conducted, enrolling 1,870 community-dwelling and 574 hospital-checkup elderly Han Chinese males aged ≥50 years. All subjects completed a structured questionnaire and had their bone mineral density (BMD) measured using DXA. Using logistic regression analysis in the 1,870 community-dwelling males, we assessed the ability of numerous potential clinical risk factors to identify male with osteoporosis. Multiple variable regression analysis and item reduction yielded a final tool named the Beijing Friendship Hospital Osteoporosis Self-assessment Tool for Elderly Male (BFH-OSTM). Receiver operating characteristic (ROC) curve was generated to compare the validation of the BFH-OSTM and Osteoporosis Self-assessment Tool for Asians (OSTA) for identifying elderly male at increased the risk of primary osteoporosis in the 574 hospital-checkup males.ResultsIn screening the 1,870 community-dwelling subjects with DXA, 14.2% (266/1,870) had osteoporosis, and a further 51.8% (969/1,870) had osteopenia. Of the items screened in the questionnaire, weight, height and previous history of fragility fracture were predictive of osteoporosis. A final tool (BFH-OSTM) was based on body weight and fragility fracture history only. The BFH-OSTM index (cutoff =70) had a sensitivity of 85% and specificity of 53% for identifying osteoporosis according to the WHO criteria, with an area under the ROC curve of 0.763. The predictive value of BFH-OSTM was validated in the 574 hospital-checkup population, which performed better than OSTA.ConclusionThe BFH-OSTM may perform well for identifying elderly male at increased risk for osteoporosis and applying it would result in more prudent use of BMD measurement by DXA, especially for Han Chinese male.

Biomarkers for Osteoporosis Management

Osteoporosis is a systemic disease characterized by low bone mass and microarchitectural deterioration of bone tissue, resulting in an increased risk of fracture. While the level of bone mass can be estimated by measuring bone mineral density (BMD) using dual X-ray absorptiometry (DXA), its measurement does not capture all the risk factors for fracture. Quantitative changes in skeletal turnover can be assessed easily and non-invasively by the measurement of serum and urinary biochemical markers; the most sensitive markers include serum osteocalcin, bone specific alkaline phosphatase, the N-terminal propeptide of type I collagen for bone formation, and the crosslinked C- (CTX) and N- (NTX) telopeptides of type I collagen for bone resorption. Advances in our knowledge of bone matrix biochemistry, most notably of post-translational modifications in type I collagen, are likely to lead to the development of new biochemical markers that reflect changes in the material property of bone, an important determinant of bone strength. Among those, the measurement of the urinary ratio of native (alpha) to isomerized (beta) CTX - an index of bone matrix maturation - has been shown to be predictive of fracture risk independently of BMD and bone turnover. In postmenopausal osteoporosis, levels of bone resorption markers above the upper limit of the premenopausal range are associated with an increased risk of hip, vertebral, and nonvertebral fracture, independent of BMD. Therefore, the combined use of BMD measurement and biochemical markers is helpful in risk assessment, especially in those women who are not identified as at risk by BMD measurement alone. Levels of bone markers decrease rapidly with antiresorptive therapies, and the levels reached after 3-6 months of therapy have been shown to be more strongly associated with fracture outcome than changes in BMD. Preliminary studies indicate that monitoring changes of bone formation markers could also be useful to monitor anabolic therapies, including intermittent parathyroid hormone administration and, possibly, to improve adherence to treatment. Thus, repeated measurements of bone markers during therapy may help improve the management of osteoporosis in patients.

The use of multiple sites for the diagnosis of osteoporosis

It has been suggested that bone mineral density (BMD) measurements should be made at multiple sites, and that the lowest T-score should be taken for the purpose of diagnosing osteoporosis. The aim of this study was to examine the use of BMD measurements at the femoral neck and lumbar spine alone and in combination for fracture prediction. We studied 19,071 individuals (68% women) from six prospective population-based cohorts in whom BMD was measured at both sites and fracture outcomes documented over 73,499 patient years. BMD values were converted to Z-scores, and the gradient of risk for any osteoporotic fracture and for hip fracture was examined by using a Poisson model in each cohort and each gender separately. Results of the different studies were merged using weighted beta-coefficients. The gradients of risk for osteoporotic fracture and for hip fracture were similar in men and women. In men and women combined, the risk of any osteoporotic fracture increased by 1.51 [95% confidence interval (CI)=1.42-1.61] per standard deviation (SD) decrease in femoral-neck BMD. For measurements made at the lumbar spine, the gradient of risk was 1.47 (95% CI=1.38-1.56). Where the minimum of the two values was used, the gradient of risk was similar (1.55; 95% CI=1.45-1.64). Higher gradients of risk were observed for hip fracture outcomes: with BMD at the femoral neck, the gradient of risk was 2.45 (95% CI=2.10-2.87), with lumbar BMD was 1.57 (95% CI=1.36-1.82), and with the minimum value of either femoral neck and lumbar spine was 2.11 (95% CI=1.81-2.45). Thus, selecting the lowest value for BMD at either the femoral neck or lumbar spine did not increase the predictive ability of BMD tests. By contrast, the sensitivity increased so that more individuals were identified but at the expense of specificity. Thus, the same effect could be achieved by using a less stringent T-score for the diagnosis of osteoporosis. Since taking the minimum value of the two measurements does not improve predictive ability, its clinical utility for the diagnosis of osteoporosis is low.

Screening for osteoporotic on high fracture risk women by questionnaire

Patients with low bone mineral density (BMD) have a high risk of future fractures, and should be actively considered for treatment to reduce their risk. Simple risk assessment questionnaires have been designed to increase awareness of osteoporosis and encourage the appropriate use of BMD measurements. These questionnaires may help target high-risk women for BMD measurements, thereby avoiding the cost of measuring women at low risk. Applying these assessment tools may encourage appropriate use of BMD technology.

Underuse of Procedures for Diagnosing Osteoporosis and of Therapies for Osteoporosis in Older Nursing Home Residents

Objective To investigate the prevalence of osteoporosis, the prevalence of utilization of bone mineral density (BMD) measurements for diagnosis of osteoporosis, and prevalence of use of calcium and vitamin D supplements and other antiresorptive therapies for treatment of osteoporosis in postmenopausal women in an academic nursing home. Methods The charts of all women aged 56 years and older residing in an academic nursing home were analyzed by one of the authors for the prevalence of osteoporosis, the prevalence of use of BMD measurements to diagnose osteoporosis, and the prevalence of use of calcium and vitamin D supplements and other antiresorptive therapies for treatment of osteoporosis. Results Of 136 postmenopausal women, mean age 79 ± 10 years, 66 (49%) had measurements of BMD. Of these 66 women, 31 (47%) had osteoporosis, 21 (32%) had osteopenia, and 14 (21%) had normal BMD. Elemental calcium carbonate 1500 mg daily was prescribed to 17 of 31 women (55%) with osteoporosis, to 12 of 21 women (57%) with osteopenia, to 2 of 14 women (14%) with normal BMD, and to 27 of 70 women (39%) with no BMD obtained. Any dose of calcium was prescribed to 78 of 136 elderly women (58%). Vitamin D supplements were prescribed to 13 of 31 women (42%) with osteoporosis, to 9 of 21 women (43%) with osteopenia, to 2 of 14 women (14%) with normal BMD, and to 20 of 70 women (29%) with no BMD obtained. Vitamin D supplements were prescribed to 44 of 136 elderly women (32%). Biphosphonates were prescribed to 19 of 31 women (61%) with osteoporosis. Of 20 women on medications that increased the risk of osteoporosis, 6 (30%) had BMD measured. Nine of these 20 women (45%) were on calcium supplements. Conclusions Older postmenopausal women in an academic nursing home have a high prevalence of osteoporosis and osteopenia, a low prevalence of measurement of BMD, and underuse of calcium, vitamin D supplements, and other antiresorptive therapies for treatment of osteoporosis.

Interest of a prescreening questionnaire to reduce the cost of bone densitometry.

Bone mineral density (BMD) measurement is widely recognized as the best single tool to identify patients with a high lifetime risk of developing an osteoporosis-related fracture. However, the cost/benefit value of screening the whole population has been repeatedly challenged and demonstrated to be rather poor. In many countries, BMD scan is not or no longer reimbursed because of lack of validated criteria to identify patients who should benefit from this procedure. Based on the proposals of a nationwide expert panel, a simple questionnaire identifying historical, clinical and behavioral risk factors for osteoporosis was developed. The aim of this study was to assess the diagnostic accuracy of the proposed criteria; to determine the extent to which this questionnaire could be useful for optimizing the use of densitometry tests; and, more specifically, to estimate the diagnostic costs per osteoporotic or osteopenic patient detected. For this purpose, we applied the questionnaire to 3998 consecutive individuals at least 20 years old, of both genders, either consulting spontaneously or referred for a BMD measurement to an outpatient osteoporosis center. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and at the hip (both total hip and femoral neck). Diagnostic accuracies were evaluated through measures of sensitivity, specificity, and positive and negative predictive values. After determining a benchmark value for age, different strategies were compared in order to identify the most cost-effective one in terms of cost per patient detected. According to the WHO operational definition of osteoporosis (T-score <-2.5), 31% of the subjects were classified as osteoporotic at one or more of the measured sites. If only patients with at least one of the proposed risk factors had been referred for scans, 33.3% of the BMD measurements would have been avoided. Among those, less than 5% were missclassified as they did have osteoporosis at the total hip and up to 23% at one or more of the considered sites. On the other hand, of the subjects who would be recommended for a densitometry test, only a small fraction were identified correctly (the positive predictive values varied from 11.3% at the total hip to 34.8% at any site). In this first setting, the suggested criteria seem useful chiefly for excluding subjects who do not need a DXA scan rather than selecting osteoporotic patients. When applied only to patients aged 61 years or more, the positive predictive values rose to 15.1% (total hip) and 42.9% (any site), whereas the corresponding negative predictive values were set at 93% and 68.6%. In comparison, with a mass screening scenario the estimated diagnostic costs (costs associated with the DXA procedure) per osteoporotic patient detected at any of the considered sites would be reduced by more than 9% (59.4 instead of 65.3 Euros) if the suggested indications are taken into account for prescreening patients. And when the questionnaire is applied only to women over the age of 60 years these costs would be further reduced to 50.6 Euros, representing a 23% decrease. Then, a prescreening strategy based on these indications concomitantly with an age-selective criterion could represent a promising way toward a more rational use of BMD measurement.

Bioactive glass as bone-graft substitute for posterior spinal fusion in rabbit.

Bioactive glass S53P4 and autogenous bone were studied as bone graft materials for spinal fusion in a rabbit model. Sixteen rabbits underwent surgery by a dorsal approach. A bioactive glass, a combination of bioactive glass and autogenous bone (70/30 vol%), and autogenous bone were implanted at two thoracolumbar vertebraes for 4 and 12 weeks. The volume, consolidation to vertebrae, and fusion of the graft material were evaluated with plain-film radiology, computed tomography (CT) and bone-mineral density measurements, and compared with histomorphometrical measurements. Radiological consolidation by CT of bone graft to underlying vertebrae at 12 weeks was observable in all groups. This was histologically confirmed as bone was growing from the vertebrae into the graft material. Radiologic fusion of vertebraes was, at 12 weeks, observable in all groups in 50--75% of the cases. The radiologic fusion seen at the CT scans could, however, not be confirmed by histology in any of the three groups. Significant differences for graft material and observation period with the use of bone-mineral density measurements (Hounsfield units) were also observable, with the highest measured values for the bioactive glass group and the lowest for the autogenous bone group. The results indicate that bioactive glass have potential as bone-graft material in spinal fusion. The reliability of radiologic evaluation methods in spinal surgery using bone substitutes is also questioned and discussed.

Ultrasound measurement using CUBA clinical system can discriminate between women with and without vertebral fractures. Contact Ultrasound Bone Analyzer.

The purpose of this study was to assess the ultrasound (US) parameters measured by Contact Ultrasound Bone Analyser (CUBA) clinical system for discriminating the subjects with vertebral fractures from those without vertebral fractures. The subjects consisted of 114 postmenopausal women over age 50 (mean +/- SD: 72.2 +/- 8.7). Seventy-three had vertebral fractures (fracture group) and 41 had no vertebral fractures (control group). Values of all US parameters and bone mineral density (BMD) in the fracture group were significantly lower than those in the control group, even after adjusting for age. Areas under the receiver operating characteristic (ROC) curve was 0.768 +/- 0.056 (mean +/- SE) for broadband ultrasound attenuation (BUA) 0.828 +/- 0.045 for velocity of sound (VOS), 0.707 +/- 0.058 for lumbar spine, 0.872 +/- 0.050 for femur neck, 0.790 +/- 0.050 for trochanter, and 0.695 +/- 0.060 for Ward's triangle. There were no significant differences among the areas under the ROC curves in BUA, VOS, lumbar spine, femur neck, trochanter, and Ward's triangle. US parameters (BUA and VOS) had the same discriminatory power as spine and hip BMD for evaluating the vertebral fracture risk. As far as disadvantages of the use of BMD measurement against US measurement, US measurement is potentially useful for screening of vertebral fractures. However, the bias concerning the propotion of the number of patients with or without vertebral fractures could not be neglected in this study.