New or worsening lumbar spine vertebral fractures increase lumbar spine bone mineral density and falsely suggest improved skeletal status.

Changes in lumbar spine bone mineral density (BMD) are determined by follow-up dual-energy x-ray absorptiometry (DXA) assessments. Inclusion of new or worsening vertebral fractures in follow-up measurements may increase BMD. To test this hypothesis, we examined pooled data from the placebo groups of two clinical trials that involved postmenopausal women with osteoporosis. DXA measurements of lumbar spine BMD, bone mineral content (BMC), and area were obtained at baseline and at two years in the Multiple Outcomes of Raloxifene Evaluation (MORE) Trial and at baseline and study endpoint in the Fracture Prevention Trial. In these trials, fractured vertebrae identified by expert radiologists during posterioranterior (PA) spine DXA assessment were excluded from the BMD assessment. Lateral spine radiographs were graded using a semi-quantitative (SQ) scale. Most new or worsening vertebral fractures (84%) diagnosed from lateral spine radiographs were not identified by PA spine DXA. While the follow-up BMD of vertebrae without new or worsening fractures did not change significantly, each unit increase in SQ grade was associated with an approximate 7.0% increase in the BMD of affected vertebrae (p < 0.001). Increases in BMD were highly correlated with increases in BMC (r = 0.87, p < 0.001). Inclusion of new or worsening vertebral fractures increased PA spine BMD measurements at follow-up, with the impact being related to the magnitude of change in SQ score. It is difficult to reliably identify vertebral fractures from PA spine DXA assessments. Inclusion of new or worsening vertebral fractures in follow-up DXA measurements may falsely suggest an improvement in spine BMD. Our suggestion is to perform lateral spine imaging concurrently with any assessment of PA spine BMD in patients who, in the opinion of the health care provider, may have vertebral fractures.     

Impact of Spinal Degenerative Changes on the Evaluation of Bone Mineral Density with Dual Energy X-Ray Absorptiometry (DXA)

The purpose of this study is to evaluate degenerative factors in a postmenopausal patient group and differentiate the influence on bone mineral density (BMD) measurements by dual-energy X-ray absorptiometry (DXA). The patients and methods included an investigation of 144 postmenopausal women (mean 63.3 years) with PA-DXA of the spine. Degenerative factors (osteophytes, osteochondrosis, scoliosis, and vascular calcification) were evaluated from plain lumbar radiographs, their estimated probability was analyzed as a function of age, and their influence on BMD measured by PA-DXA was determined. The results of the study revealed osteophytes in 45.8%, vascular calcifications in 24.3%, scoliosis in 22.2%, osteochondrosis in 21.5%. The estimated probability for degenerative factors increased from 35 to 80% in the 55- to 70- year age group. Osteophytes and osteochondrosis were associated with up to a 14% increase in BMD values (P < 0.001). Vascular calcifications showed a positive trend, whereas scoliosis did not show a discernible influence. We concluded that degenerative factors, except for scoliosis, showed an influence on BMD as measured by DXA. Their prevalence increased rapidly between 55 and 70 years of age. Interpretation of PA-DXA spine data for subjects of or above this age range should be complemented by plain film radiographs. Received: 30 May 1996 / Accepted: 24 July 1996     

Trabecular Bone Score: A Noninvasive Analytical Method Based Upon the DXA Image

The trabecular bone score (TBS) is a gray‐level textural metric that can be extracted from the two‐dimensional lumbar spine dual‐energy X‐ray absorptiometry (DXA) image. TBS is related to bone microarchitecture and provides skeletal information that is not captured from the standard bone mineral density (BMD) measurement. Based on experimental variograms of the projected DXA image, TBS has the potential to discern differences between DXA scans that show similar BMD measurements. An elevated TBS value correlates with better skeletal microstructure; a low TBS value correlates with weaker skeletal microstructure. Lumbar spine TBS has been evaluated in cross‐sectional and longitudinal studies. The following conclusions are based upon publications reviewed in this article: 1) TBS gives lower values in postmenopausal women and in men with previous fragility fractures than their nonfractured counterparts; 2) TBS is complementary to data available by lumbar spine DXA measurements; 3) TBS results are lower in women who have sustained a fragility fracture but in whom DXA does not indicate osteoporosis or even osteopenia; 4) TBS predicts fracture risk as well as lumbar spine BMD measurements in postmenopausal women; 5) efficacious therapies for osteoporosis differ in the extent to which they influence the TBS; 6) TBS is associated with fracture risk in individuals with conditions related to reduced bone mass or bone quality. Based on these data, lumbar spine TBS holds promise as an emerging technology that could well become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment. © 2014 American Society for Bone and Mineral Research.     

Influence of degenerative joint disease on spinal bone mineral measurements in postmenopausal women

We assessed the impact of various forms of spinal degenerative joint disease (DJD) on bone mineral density (BMD) measured by quantitative computed tomography (QCT) and dual X-ray absorptiometry (DXA) in a group of postmenopausal women. Lateral (T4-L4) and AP (L1-L4) spinal radiographs were reviewed for fracture and DJD in 209 women (mean age 62.6±6.7). The severity of DJD findings was graded as 0,1, or 2 on the lumbar films, except for vertebral osteophytes which were graded from 0 to 3. Vertebral fractures were defined semiquantitatively as approximately 20% reduction in anterior, middle, or posterior vertebral height. BMD was measured in all subjects by QCT and DXA, including posteroanterior DXA (PA-DXA), lateral DXA (L-DXA) and midlateral DXA (mL-DXA). When BMD was measured by QCT and mL-DXA in the 168 women without fractures, no significant differences were found between women with and those without DJD. However, BMD by PA-DXA was significantly higher in women with DJD changes, particularly when osteophytes were present at the vertebral bodies or facet joints. BMD by L-DXA was less affecied by DJD. For this measurement a significant increase in BMD was only noted in subjects with vertebral osteophytes. Multivariate analysis of variance (MANOVA) showed that BMD by QCT and mL-DXA was not affected by DJD. In contrast, for all women, BMD by PA-and L-DXA was affected more by DJD than by fracture status. Chi-square testing demonstrated no significant relationships between vertebral fractures and any of the DJD changes. We conclude that QCT and mL-DXA are superior to PA-DXA and L-DXA in detecting bone loss in patients with DJD. Thus, for these patients, BMD assessment by QCT or mL-DXA may be advisable.     

Association of the OSCAR promoter polymorphism with BMD in postmenopausal women.

In an effort to identify genetic polymorphisms in potential candidate genes for osteoporosis, 10 variants were identified in the OSCAR gene using direct DNA sequencing, and 560 postmenopausal women were genotyped at five SNP loci, using the TaqMan method. The rare allele (G allele) of OSCAR-2322A>G (SNP in the 5' flanking region) showed significant association with lower BMD at various bone sites in postmenopausal women (n = 560). INTRODUCTION: BMD is the major factor for determining bone strength and osteoporotic fracture risk and is determined by both environmental and multiple genetic factors. The osteoclast-associated receptor (OSCAR) plays a critical role in osteoclast differentiation and thus is an important candidate gene for the modulation of BMD. MATERIALS AND METHODS: Through direct sequencing in 24 Korean individuals, 10 sequence variants were identified: 2 in the 5' flanking region, 7 in the exons (including 6 nonsynonymous single-nucleotide polymorphisms [SNPs]), and 1 in an intron. Five of these polymorphisms were selected for larger-scale genotyping in postmenopausal women (n = 560). Areal BMD (g/cm2) of the anterior-posterior lumbar spine and the nondominant proximal femur was measured using DXA (Lunar Expert XL and Hologic QDR 4500-A). Lateral thoracolumbar radiographs were obtained in all subjects. RESULTS: Using multiple regression analysis and controlling for age, years since menopause, height, weight, and evaluation machine as covariates, the rare allele (G allele) of OSCAR-2322A>G showed significant association with lower BMD at various bone sites in postmenopausal women. CONCLUSION: These findings suggest that the promoter variant in OSCAR gene (OSCAR-2322A>G) might be one of genetic determinants of BMD in postmenopausal women.     

IL-33与绝经后骨质疏松女性骨密度和骨代谢指标相关性研究

目的 探索血清白细胞介素-33(IL-33)与绝经后骨质疏松女性骨密度和骨代谢指标相关性。方法 采用酶联免疫吸附法测定50例绝经后骨质疏松患者和50例正常绝经后妇女血清IL-33水平。采用双能X线骨密度仪(DXA)测量患者和对照组的骨密度(BMD)。检测维生素D、钙、碱性磷酸酶(ALP)、甲状旁腺激素(PTH)水平,以及1型胶原C末端肽(CTX)和1型前胶原N端前肽(P1NP)等骨转换指标。结果 在绝经后骨质疏松症女性中,IL-33水平显著低于健康对照组[(3.53±2.45) pg/mL vs (13.72±5.39) pg/mL,P=0.007];Spearman相关分析表明血清IL-33水平与年龄、BMI、PTH、CTX和P1NP水平呈负相关,与腰椎BMD和股骨颈BMD呈正相关。多元回归分析表明,年龄、BMI、腰椎BMD、PTH、股骨颈BMD和血清CTX和P1NP水平是骨质疏松症患者血清IL-33水平降低的独立预测因子。结论 血清IL-33降低是绝经后骨质疏松患者股骨颈和腰椎骨密度降低和骨转换增速的危险因素。     

Bone mass continues to increase at the hip after parathyroid hormone treatment is discontinued in glucocorticoid-induced osteoporosis: results of a randomized controlled clinical trial.

Glucocorticoid-induced osteoporosis is the most common secondary cause of osteoporosis. In this 24-month study, we report changes in bone turnover and bone mass after 12 months of daily injections of human parathyroid hormone 1-34 [hPTH(1-34)] and 12 months off treatment in postmenopausal women (mean age, 63 years) with osteoporosis treated with glucocorticoid and hormone replacement therapy. Response to the treatment was assessed with bone mineral density (BMD) measurements of the lumbar spine by quantitative computed tomography (QCT); BMD measurements of the lumbar spine, hip, and forearm by dual-energy X-ray absorptiometry (DXA); and biochemical markers of bone turnover. The mean (+/-SEM) change in BMD of the lumbar spine by QCT and DXA in the PTH group at 24 months was 45.9+/-6.4% and 12.6+/-2.2% (p < 0.001). The change in total hip and femoral neck BMD was not significant at 12 months but increased to 4.7+/-0.9% (p < 0.01) and 5.2+/-1.3% at 24 months, respectively, as compared with a relatively small change of 1.3+/-0.9% and 2.6+/-1.7% in the estrogen-only group. The mean percent differences in BMD of the lumbar spine by QCT and DXA between the groups at 24 months were 43.1% and 11.9%, respectively (p < 0.001). The mean percent differences over the estrogen-only group in hip BMD were 3.4% for total hip (p < 0.01) and 2.6% for femoral neck at 24 months. Biochemical markers of bone turnover increased to more than 150% during the first 6 months of therapy, remained elevated throughout the 12-month treatment period, and returned to baseline values within 6 months of discontinuing the PTH treatment. These results suggest that PTH dramatically increases bone mass in the lumbar spine and hip in postmenopausal women with glucocorticoid-induced osteoporosis who are taking hormone replacement therapy. However, the maximum effect of this anabolic agent on bone mass at the hip after 12 months of treatment requires at least 6-12 months after the PTH treatment is discontinued.     

Hyperthyroidism Influences Ultrasound Bone Measurement on the Os Calcis

The objective of our study was to compare bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) parameters in women with hyperthyroidism and controls. In this cross-sectional study, QUS parameters and BMD values observed in untreated hyperthyroid patients were compared with data obtained from age-matched controls. Twenty-four women with Graves' disease were studied. Eight patients were postmenopausal. All patients had evidence of thyrotoxicosis as indicated by a raised total serum thyroxine and a suppressed serum thyroid stimulating hormone. BMD of the hip, lumbar spine and whole body, and body composition, were measured by DXA. Ultrasound evaluation on the os calcis was performed with an Achilles device. All measurements were performed before antithyroid therapy. The QUS parameters of BUA, SOS and Stiffness were significantly lower in hyperthyroid patients than in controls. Similar results were observed for the BMD of lumbar spine, femoral neck and total skeleton. Lean tissue and fat mass were also significantly decreased in hyperthyroid patients. In conclusion, these findings suggest that hyperthyroidism affects cortical and trabecular bone equally, as well as bone quality. QUS measurements may be helpful for assessing, using a simple and non-irradiating method, the bone effects of thyrotoxicosis. Received: 9 June 1997 / Accepted: 27 October 1997     

Use of a Swedish T-score reference population for women causes a two-fold increase in the amount of postmenopausal Swedish patients that fulfill the WHO criteria for osteoporosis

The WHO criteria for osteoporosis are based on bone mineral density (BMD) values in comparison to a reference population of healthy young adults. The aim of this study was to create BMD references for ethnic Swedish women, and to investigate whether the use of these T-score measurements influence the amount of Swedish postmenopausal patients that are diagnosed as having osteoporosis. A bone density reference was created by measuring a population-based sample of 335 randomly selected Swedish women aged 20-39yr. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, proximal femur, and total body. These locally derived T-score values were subsequently used to diagnose a sample of 300 consecutive postmenopausal Swedish patients referred to the Uppsala Osteoporosis Unit. There was a slight age-dependent decrease in femoral neck BMD, whereas no age effect was seen at other sites such as total hip, lumbar spine, or total body. This suggests that the cohort represents the steady state BMD at the ages of expected peak bone mass in Swedish women. The correlation between BMD measures at different sites differed from r=0.55 (lumbar spine BMD vs femoral neck BMD [FNBMD]) to r=0.92 (total hip BMD vs FNBMD). Central DXA-generated T-scores were calculated from this cohort, and these were significantly higher (0.3-0.5 SD) as compared with manufacturers and NHANESIII reference populations. This indicates that young Swedish women have a higher peak bone mass than the subjects included in the reference populations currently used for clinical measurements. The T-score in total hip derived from the investigated cohort was subsequently used to diagnose 300 clinical patients (mean age 63yr) referred for a DXA scan by their physicians. The use of this locally established and ethnic representative, T-score reference increased the prevalence of osteoporosis in femoral neck and total hip with 53-106%. A Swedish female BMD reference representing peak bone mass has been established and the normative data are presented. Notably, this cohort has considerably higher BMD as compared to the NHANESIII and manufacturer's reference populations. The use of the present T-score reference therefore causes approximately a 2-fold increase in the amount of Swedish postmenopausal women that fulfill the WHO criteria for osteoporosis. This demonstrates the problems with using T-score as diagnostic threshold for osteoporosis and is an argument for future strategies to obtain standardized densitometric cut-offs, for example, mg/cm(2).     

Calcaneus Ultrasonometry and Dual-Energy X-Ray Absorptiometry for the Evaluation of Vertebral Fracture Risk

The aim of this retrospective, cross-sectional, controlled, non-population-based study was to evaluate the specificity and sensitivity of quantitative ultrasonometry (QUS) of the heel and of dual-energy X-ray absorptiometry (DXA) in the prediction of morphometric vertebral fracture in postmenopausal women and to establish whether the combination of the two devices could improve the capacity to identify the presence of vertebral fracture. Also, we tried to identify the best T-score threshold for high risk of vertebral fracture for both QUS and DXA, highlighting the discrepancies between the two methodologies and between the various sites examined with DXA. From 6,300 patients examined by DXA (total body, lumbar spine, total femur, femoral neck), QUS and DXA vertebral morphometry (MXA), we selected 764 postmenopausal women with nontraumatic vertebral fractures; 770 postmenopausal women with normal morphometry were chosen as a control group. Logistic regression analysis yielded odds ratios (ORs) for bone mineral density (BMD) measurements and QUS that were comparable: BMD-total body 4.16, BMD-lumbar spine 4.80, BMD-total femur 3.77, BMD-femoral neck 3.86, and QUS 4.41, without statistical differences even after correction for different confounding variables (menopausal years, weight, height, body mass index, and age). The ORs obtained from different combinations of QUS and DXA results did not show statistically significant differences compared to those from a single method alone. The sensitivity and specificity of all measurements were determined by area using the receiver operating characteristic curve; these were 0.94 for total body, 0.95 for lumbar spine, 0.86 for total femur, 0.89 for femoral neck, and 0.93 for QUS, without statistical difference. The areas under the curve obtained from the combination of QUS and DXA were higher but without statistical significance compared to QUS alone. In conclusion, both QUS and DXA were able to discriminate women with fracture from women without fracture and independently contributed to determining the association with fracture. The combination of QUS and BMD did not improve the diagnostic ability of either individual technique. We found different diagnostic thresholds for QUS and DXA.     

Discriminatory ability of quantitative ultrasound parameters and bone mineral density in a population-based sample of postmenopausal women with vertebral fractures: results of the Basel Osteoporosis Study.

The discriminatory potential to classify subjects with or without vertebral fractures was tested cross-sectionally with different methods for the measurement of bone status in a population-based sample of postmenopausal women. Quantitative ultrasound (QUS) measurement at the calcaneus (Lunar Achilles, Hologic Sahara), the proximal phalanges (Igea Bone Profiler), and measurement of bone mineral density (BMD) with dual-energy X-ray absorptiometry (DXA; Lunar Expert) at several anatomic sites was performed in 500 postmenopausal women (aged 65-75 years) randomly selected from the population. In addition, 50 young female subjects (20-40 years old) had QUS measurements and served as controls to express QUS results as T-score values. Radiographs of the lumbar and thoracic spine were performed in the elderly women. Two independent radiologists reviewed the X-rays for the presence of vertebral fractures. Of 486 eligible study participants, no fracture was seen in 396 participants. Single vertebral fractures were observed in 71 subjects; 19 individuals presented multiple fractures. The overall prevalence of vertebral fractures was 18.5%. Participants without vertebral fractures were compared with subjects with vertebral fractures. Normal statistical distributions were found for all bone measurement results. Risk of vertebral fracture in subjects with no and multiple vertebral fracture was estimated using age adjusted odds ratios (ORs) for QUS and dual-energy X-ray absorptiometry (DXA) values. Each SD decrease in bone measurement increased the risk of multiple vertebral fracture by 3.0 (95% CI, 1.6-5.6) for the Achilles stiffness, by 3.8 (95% CI, 1.8-8.2) for the Sahara QUI, 2.1 (95% CI, 1.3-3.4) for the Bone Profiler amplitude-dependent speed of sound (AD-SOS), and 2.1 (95% CI, 1.2-3.9) and 2.4 (95% CI, 1.3-4.3) for DXA lumbar spine and for DXA total hip, respectively. Results of a discriminant analysis showed sensitivities between 84% and 58% and specificities between 72% and 58% for the respective DXA and QUS parameters. Optimum fracture thresholds for QUS measurements derived from this analysis were calculated also. Optimum T-score threshold values for QUS measurements tended to be higher than those for DXA measurements. However, the performance of QUS measurements is at least comparable with DXA measurements in identifying subjects with multiple vertebral fractures randomly selected from the population.     

The relationship between bone mineral density and ultrasound in postmenopausal and osteoporotic women

The aim of this cross-sectional study was to use a novel method of data analysis to demonstrate that patients with osteoporosis have significantly lower ultrasound results in the heel after correcting for the effect of bone mineral density (BMD) measured in the spine or hip. Three groups of patients were studied: healthy early postmenopausal women, within 3 years of the menopause (n=104, 50%), healthy late postmenopausal women, more than 10 years from the menopause (n=75, 36%), and a group of women with osteoporosis as defined by WHO criteria (n=30, 14%). Broadband ultrasound attenuation (BUA), speed of sound (SOS) and Stiffness were measured using a Lunar Achilles heel machine, and BMD of the lumbar spine and left hip was measured using dual-energy X-ray absorptiometry (DXA). SOS, BUA and Stiffness were regressed against lumbar spine BMD and femoral BMD for all three groups combined. The correlation coefficients were in the range 0.52–0.58, in agreement with previously published work. Using a calculated ratio R, analysis of variance demonstrated that the ratio was significantly higher in the osteoporotic group compared with the other two groups. This implied that heel ultrasound values are proportionately lower in the osteoporotic group compared with the other two groups for an equivalent value of lumbar spine and femoral neck BMD. We conclude that postmenopausal bone loss is not associated with different ultasound values once lumbar spine or femoral neck BMD is taken into account. Ultrasound does not give additional information about patterns of bone loss in postmenopausal patients but is important in those patients with osteoporosis and fractures.     

3D Analysis of Cortical and Trabecular Bone From Hip DXA:Precision and Trend Assessment Interval in PostmenopausalWomen

The 3D distribution of the cortical and trabecular bone mass is a critical component in determining the resistance of a bone to fracture that is not assessed in standard dual-energy X-ray absorptiometry (DXA) exams. In this work, we assessed in vivo short-term precision of measurements provided by 3D modeling techniques from DXA scans and trend assessment intervals (TAIs) in postmenopausal women. Subjects included to study precision errors were scanned twice, with repositioning for duplicate hip scans, using either a Lunar iDXA scanner (GE Healthcare, Madison, WI) or a Discovery W scanner (Hologic, Inc., Waltham, MA). Postmenopausal women having baseline and 18-mo follow-up visit were scanned using a Lunar iDXA device to assess TAIs. TAIs indicate what time intervals are required to allow accurate assessment of response to treatment or progression of disease. The 3D-SHAPER software (Galgo Medical, Barcelona, Spain) was used to derive 3D measurements from hip DXA scans. Least significant changes were 10.39 and 8.72 mg/cm³ for integral volumetric bone mineral density (BMD), 9.64 and 9.59 mg/cm³ for trabecular volumetric BMD, and 6.25 and 5.99 mg/cm² for cortical surface BMD, using the Lunar iDXA and Discovery W scanners, respectively. TAIs in postmenopausal women were 2.9 yr (integral volumetric BMD), 2.6 yr (trabecular volumetric BMD), and 3.5 yr (cortical surface BMD), using the Lunar iDXA scanner. As a comparison, TAIs for areal BMD were 2.8 yr at neck and 2.7 yr at total femur. Least significant changes of measurements provided by 3D modeling techniques from DXA were assessed. TAIs in postmenopausal women were similar to those measured for areal BMD measurements. DXA-derived 3D measurements could potentially provide additional indicators to improve patient monitoring in clinical practices.     

Comparison of bone densitometry of the phalanges,distal forearm and axial skeleton in early postmenopausal women participating in the EPIC study

We present baseline bone densitometry from the Early Postmenopausal Interventional Cohort study (EPIC, sponsored by Merck, Sharp & Dohme) for the first time, in which 1609 women from England, Oregon, Hawaii and Denmark are participating to investigate the efficacy of daily oral alendronate to prevent early postmenopausal bone loss. We compared radiographic absorptiometry (RA) of the phalanges for bone mineral density (BMD) measurement with single-energy X-ray absorptiometry (SXA) of the distal forearm, and dual-energy X-ray absorptiometry (DXA) of the lumbar spine, proximal femur and distal forearm. In a random subgroup of 308 women, aged 45–60 years, on average 6 years since menopause (YSM), bone densitometry was measured once at baseline by RA of the phalanges besides the mandatory measurements by DXA. Bone densitometry was furthermore measured by SXA at the Danish site (89 women). Sixty-eight of the women had duplicate measurements performed within 1–3 weeks to evaluate the short-term precision error (CV%). One hundred and one healthy premenopausal women, aged 25–48 years, were recruited at the Danish and Hawaiian sites to establish a reference group. The precision error was 1.5% for RA of the phalanges and in the range 1.0–2.2% for SXA and DXA. BMD by RA correlated with BMD measured by SXA and DXA in the range 0.45<r<0.72 (p<0.001). In conclusion, bone densitometry by RA of the phalanges is highly correlated with bone densitometry by SXA and DXA. RA of the phalanges has a short-term precision error comparable to that of SXA and DXA.     

Differential effects of hormone replacement therapy on bone mineral density and axial transmission ultrasound measurements in cortical bone

The menopause has a large effect on bone density, and hormone replacement therapy (HRT) has been shown to be an effective treatment for preventing postmenopausal bone loss. The aim of this study was to compare the effects of HRT use on speed of sound (SOS) measurements at the radius, tibia, phalanx, and metatarsal with bone mineral density (BMD) measurements of the lumbar spine and proximal femur. The study population consisted of 278 healthy premenopausal women, 194 healthy postmenopausal women, and 126 healthy postmenopausal women currently receiving HRT for one or more years. SOS measurements were taken at the radius, tibia, phalanx, and metatarsal using the Sunlight Omnisense, and BMD measurements at the lumbar spine and proximal femur using Hologic QDR-4500 densitometers. Z-scores were calculated using the postmenopausal control group. Z-score differences between the postmenopausal controls and HRT group, for the entire group and with the HRT group subdivided into three groups based on duration of HRT usage, were calculated. Significant postmenopausal bone loss was found for all SOS and BMD measurements. A positive effect of HRT usage was found for all SOS measurement sites and lumbar spine BMD, although only the radius and tibia SOS and lumbar spine BMD reached statistical significance. The Z-score differences between the two groups were 0.44, 0.37, 0.15, and 0.26 for the radius, tibia, phalanx, and metatarsal SOS respectively, and 0.28, 0.00, and -0.03 for the lumbar spine, femoral neck, and total hip BMD respectively. A clear effect of the duration of HRT use was seen for the radius measurements, the differences being less marked elsewhere. In conclusion, these results demonstrate a positive effect of HRT on SOS measurements at the radius and tibia and BMD measurements of the lumbar spine.     

Treatment with raloxifene for 2 years increases vertebral bone mineral density as measured by volumetric quantitative computed tomography

Volumetric quantitative computed tomography (vQCT), using multiple thin-slice acquisition, measures three-dimensional volumetric bone mineral density (BMD, mg/cm3). vQCT is often used to measure BMD of lumbar vertebrae and may detect early changes in trabecular, cortical, or integral BMD that extend beyond the technical limits of areal dual X-ray absorptiometry (DXA) BMD measurements. The objective of this study was to determine the effect of 2 years of raloxifene (RLX) treatment on several volumetric BMD measures in a subset of postmenopausal women (n=58) enrolled in the Multiple Outcomes of Raloxifene Evaluation (MORE) trial. Patients in this study were randomized to one of three treatment groups: placebo (n=21), RLX 60 mg/day (n=17), or RLX 120 mg/day (n=20), and all patients received daily calcium (500 mg) and vitamin D (400-600 IU) supplementation. Data from the raloxifene treatment groups were pooled for each analysis. Following 2 years of raloxifene treatment, there was a significant percent change from baseline in the vQCT regions of interest (ROIs) of midintegral BMD, total trabecular BMD, and total integral BMD (P<0.05) compared to placebo, while there was no significant change in the spinal DXA BMD measurement. These data provide the first longitudinal assessment by vQCT of changes in vertebral bone density after 2 years of treatment with raloxifene. vQCT appears to be a valuable technique for measuring the effects of raloxifene treatment in this population of postmenopausal women with osteoporosis.     

Discordance in lumbar bone mineral density measurements by quantitative computed tomography and dual-energy X-ray absorptiometry in postmenopausal women: a prospective comparative study

Background ContextLevel-specific lumbar bone mineral density (BMD) evaluation of a single vertebral body can provide useful surgical planning and osteoporosis management information. Previous comparative studies have primarily focused on detecting spinal osteoporosis but not at specific levels.PurposeTo compare the detection rate of lumbar osteoporosis between quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA); to explore and analyze the distribution models of QCT-derived BMD and DXA T-score at the specific levels; and to evaluate the diagnostic accuracy of level-specific BMD thresholds for the prediction of osteoporotic vertebral compression fracture (OVCF) in postmenopausal women.Study Design/SettingA comparative analysis of prospectively collected data comparing QCT-derived BMD with DXA T-score.Patient SampleA total of 296 postmenopausal women who were referred to the spine service of a single academic institution were enrolled.Outcome MeasuresQCT-derived BMD and DXA T-score at specific levels, with or without osteoporotic vertebral compression fracture.MethodsPostmenopausal women who underwent QCT and DXA within a week of admission from May 2019 to June 2022 were enrolled. The diagnostic criteria for osteoporosis recommended by the World Health Organization and the American College of Radiology were used for lumbar osteoporotic diagnosis. To evaluate differences in lumbar BMD measurements at specific levels, a threshold of T score=-2.5 and QCT-derived BMD = 80 mg/cm³ were used to categorize level-specific lumbar BMD into low and high BMD. Disagreements in BMD categorization between DXA and QCT were classified as a minor or major discordance based on the definition by Woodson. Data between QCT and DXA were visualized in a stacked bar plot and analyzed. Correlations between DXA and QCT at the specific levels were evaluated using Pearson's linear correlation and scatter plots. Curve fitting of BMD distribution, receiver operating characteristic (ROC) and area under the curve (AUC) for each single vertebral level was performed.ResultsOf the 296 patients, QCT diagnosed 61.1% as osteoporosis, 30.4% as osteopenia and 8.4% as normal. For those screened with DXA, 54.1% of the patients had osteoporosis, 29.4% had osteopenia and 16.6% had normal BMD. Diagnoses were concordant for 194 (65.5%) patients. Of the other 102 discordant patients, 5 (1.7%) were major and 97 (32.8%) were minor. Significant correlations in level-specific BMD between DXA and QCT were observed (p<.001), with Pearson's correlation coefficients ranging from 0.662 to 0.728. The correlation strength was in the order of L1 > L2 > L3 > L4. The low BMD detection rate for QCT was significantly higher than that for DXA at the L3 and L4 levels (65% vs. 47.9% and 68.1% vs 43.7, respectively, p<.001). Patients with OVCF showed significantly lower QCT-derived BMD (47.2 mg/cm³ vs. 83.2 mg/cm³, p<.001) and T-score (-3.39 vs. -1.98, p<.001) than those without OVCF. Among these patients, 82.8% (101/122) were diagnosed with osteoporosis by QCT measurement, while only 74.6% (91/122) were diagnosed by DXA. For discrimination between patients with and without OVCF, QCT-derived BMD showed better diagnosed performance (AUC range from 0.769 to 0.801) than DXA T-score (AUC range from 0.696 to 0.753).ConclusionQCT provided a more accurate evaluation of lumbar osteoporosis than DXA. The QCT-derived BMD measurements at a specific lumbar level have a high diagnostic performance for OVCF.     

Genetic effects on bone loss in peri- and postmenopausal women: a longitudinal twin study.

This longitudinal twin study was designed to assess the heritability of bone loss in peri- and postmenopausal women. A sample of 724 female twins was studied. Baseline and repeat BMD measurements were performed. Results of genetic model-fitting analysis indicated genetic effects on bone loss account for approximately 40% of the between-individual variation in bone loss at the lumbar spine, forearm, and whole body. INTRODUCTION: BMD and bone loss are important predictors of fracture risk. Although the heritability of peak BMD is well documented, it is not clear whether bone loss is also under genetic regulation. This study was designed to assess the heritability of bone loss in peri- and postmenopausal women. MATERIALS AND METHODS: A sample of 724 female twins (177 monozygotic [MZ] and 185 dizygotic [DZ] pairs), 45-82 yr of age, was studied. Each individual had baseline BMD measurements at the lumbar spine, hip, forearm, and total body by DXA and at least one repeat measure, on average 4.9 yr later. Change in BMD (DeltaBMD) was expressed as percent of gain or loss per year. Intraclass correlation coefficients for DeltaBMD were calculated for MZ and DZ pairs. Genetic model-fitting analysis was conducted to partition the total variance of DeltaBMD into three components: genetic (G), common environment (C), and specific environment, including measurement error (E). The index of heritability was estimated as the ratio of genetic variance over total variance. RESULTS: The mean annual DeltaBMD was -0.37 +/- 1.43% (SD) per year at the lumbar spine, -0.27 +/- 1.32% at the total hip, -0.77 +/- 1.66% at the total forearm, -0.36 +/- 1.56% at the femoral neck, and -0.16 +/- 0.81% at the whole body. Intraclass correlation coefficients were significantly higher in MZ than in DZ twins for all studied parameters, except at the hip sites. Results of genetic model-fitting analysis indicated that the indices of heritability for DeltaBMD were 0.38, 0.49, and 0.44 for the lumbar spine, total forearm, and whole body, respectively. However, the genetic effect on DeltaBMD at all hip sites was not significant. CONCLUSIONS: These data suggest that, although genetic effects on bone loss with aging are less pronounced than on peak bone mass, they still account for approximately 40% of the between-individual variation in bone loss for the lumbar spine, total forearm, and whole body in peri- and postmenopausal women. These findings are relevant for studies aimed at identification of genes that are involved in the regulation of bone loss.     

Validation and comparative evaluation of four osteoporosis risk indexes in Moroccan menopausal women

Introduction Measuring bone mineral density (BMD) is a widely accepted strategy for identifying subjects with an increased risk of fracture. However, because of limited availability of BMD technology in some communities and cost considerations, it has been proposed that BMD measurements be targeted to subjects with risk factors for osteoporosis. Recently, many risk assessment indices have been developed to identify women who are more likely to have low BMD and thus undergo BMD testing. The objective of this study was to compare the performance of four risk indices for osteoporosis in white women in Morocco. Methods We analysed in an epidemiological cross-sectional study the records for 986 postmenopausal white Moroccan women seen at an out-patient rheumatology centre. Four osteoporosis risk index scores were compared to bone density T-scores. The ability of each risk index to identify women with low BMD (T-score<−2.0) or osteoporosis (T<−2.5) was evaluated. Results Using an Osteoporosis Self-Assessment Tool (OST) score<2 to recommend DXA referral, we found that sensitivity ranged from 61% at the lumbar spine to 85% at the total hip to detect BMD T-scores of −2.5, and specificity ranged from 62% at the lumbar spine to 67% at the total hip. The negative predictive value was high at all skeletal sites (79–98%), demonstrating the usefulness of the OST to identify patients who have normal BMD and should not receive DXA testing. All risk indices performed similarly and showed better results in identifying women with osteoporosis or low BMD based on hip measurement. Conclusions This is the first study that validated several risk osteoporosis indexes in Moroccan women. The performance of these risk indices among women in Morocco was similar to that reported earlier for other samples in Asian countries, the US, and Belgium. The OST and other risk indices are effective and efficient tools to help target high-risk women for DXA measurement.     

Bone status in primary hyperparathyroidism assessed by regional bone mineral density from the whole body scan and QUS imaging at calcaneus

To assess the bone mineral density status in primary hyperparathyroidism (PHPT), we studied 64 females with PHPT and 17 healthy women. Regional BMD (arms, trunk, legs) from the whole body scan and conventional sites (lumbar spine, femur, radius) were assessed by DXA. Quantitative ultrasound (QUS) imaging measurements were performed at calcaneus. Sixteen women had history of renal lithiasis, 11 had low impact fracture and 37 women had neither renal lithiasis nor fracture. In the entire group, the mean Z-scores were significantly decreased at all sites (lumbar spine, femur, radius). In all clinical subgroups, the mean Z-scores were significantly decreased at radius. The mean Z-scores in premenopausal women were significantly decreased comparatively to postmenopausal women at lumbar spine and femur. In a group of PHPT females matched to controls for age and BMI, only BMD values at radius were lower in PHPT patients than in control (P < 0.03). However, from the whole body scan data, all sites but no trunk were significantly involved in PHPT patients (P < 0.04). Using QUS measurements at calcaneus, the BUA but not SOS in PHPT females was significantly lower (P = 0.03) than in controls. Our results suggest that low BMD at lumbar spine and femur is encountered preferentially in premenopausal women. The BMD decrease predominates at limbs in PHPT with presumably a gradient from proximal to distal part of the limbs. Indeed, the distal part of the limbs are the most affected areas in PHPT whatever the amount of cortical or trabecular bone.