Abstract
For Caucasian women, the QCT (quantitative CT) lumbar spine (LS) bone mineral density (BMD) cutpoint value for classifying osteoporosis is 80 mg/ml. At the age of approximate 78 years, US Caucasian women QCT LS BMD population mean is 80 mg/ml, while that of Chinese women and Japanese women is around 50 mg/ml. Correlation analyses show, for Chinese women and Japanese women, QCT LS BMD of 45 mg/ml corresponds to the dual-energy X-ray absorptiometry cutpoint value for classifying osteoporosis. For Chinese and Japanese women, if QCT LS BMD 80 mg/ml is used as the threshold to classify osteoporosis, then the specificity of classifying subjects with vertebral fragility fracture into the osteoporotic group is low, whereas threshold of 45 mg/ml approximately achieve a similar separation for women with and without vertebral fragility fracture as the reports for Caucasian women. Moreover, by using 80mg/ml as the cutpoint value, LS QCT leads to excessively high prevalence of osteoporosis for Chinese women, with the discordance between hip dual-energy X-ray absorptiometry and LS QCT measures far exceeding expectation. Considering the different bone properties and the much lower prevalence of fragility fractures in the East Asian women compared with Caucasians, we argue that the QCT cutpoint value for classifying osteoporosis among older East Asian women will be close to and no more than 50 mg/ml LS BMD. We suggest that it is also imperative the QCT osteoporosis classification criterion for East Asian male LS, and male and female hips be re-examined.
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Introduction
Osteoporosis is a systemic skeletal disease characterised by a reduction in bone mass (measured by bone mineral density: BMD) and qualitative skeletal changes that cause an increase in bone fragility and a higher fracture risk. The clinical significance of osteoporosis lies in the fragility fractures (FF) that occur. Dual-energy X-ray absorptiometry (DXA) is the current standard technique for measuring BMD. For a variety of reasons, including differences in X-ray energy generation, bone edge detection algorithms, region of interest placement, and methods of calibration, BMD by DXA in g/cm2 differs substantially among DXA manufacturers. To avoid the confusion that would result from instrument-specific numerical BMD cutpoint values, the T-score concept was proposed, whereby each patient’s value is compared with a young normative database generated on the same device. According to the criteria set by the 1994 World Health Organization (WHO) Study Group, the T-score is defined as: (BMDpatient–BMDyoung adult mean)/SDyoung adult population, where BMD is bone mineral density and SD is the standard deviation. Quantitative CT (QCT) for BMD measurement can be performed on any CT scanner with the use of a calibration phantom and dedicated analysis software (such as Mindways Software, Inc., Austin, USA). Calibration phantoms are required to transform the attenuation measured in Hounsfield units into BMD value (in mg/mL). The patient and phantom are commonly examined at the same time, which is termed as simultaneous calibration. Compared with DXA technique, QCT has a number of advantages. QCT is less susceptible to degenerative changes of the spine than DXA. Osteophytes and facet joint degeneration, as well as soft tissue calcifications, do not significantly increase BMD in QCT [1,2,3]. QCT provides trabecular bone measurements, which are more sensitive to monitoring changes with some diseases and therapies. Patients who are undergoing therapies that have a high impact on bone metabolic activity, such as parathyroid hormone and corticosteroids, may be better monitored with QCT. QCT also has advantages for patients with unusual body size or obesity. Disadvantages of QCT include the higher radiation dose, limited applicability of the WHO T-score criteria for the diagnosis of osteoporosis, and overall less experience with fracture prediction and treatment initiation with QCT compared with DXA [1,2,3].
Due to different bone structural properties and the much lower incidence of fragility fractures in the Chinese population compared with Caucasians [4, 5], we have recently recommended that, to diagnose osteoporosis using DXA with Chinese BMD reference ranges, the cutpoint T-score value for lumbar spine BMD for Chinese women should be -3.7 rather than the WHO cutpoint of -2.5 recommended for Caucasians [6,7,8]. Numerous studies have demonstrated that the skeleton of East Asians has microstructural and mechanical advantages [5]. For example, Walker et al. [9] reported that postmenopausal Chinese women have a higher trabecular plate-to-rod ratio and greater whole bone stiffness, translating into greater trabecular mechanical competence. Boutroy et al. [10] reported that, compared with Caucasians, both pre- and postmenopausal Chinese women had greater cortical thickness, cortical tissue mineral density, and reduced cortical porosity at both the radius and tibia. For the spine, compared with older Caucasian women, older Chinese women were less likely to have disc space narrowing, thoracic spine hyper-kyphosis, vertebral osteoarthritic wedging, Schmorl nodes defect, and degenerative spondylolisthesis [11, 12]. Almost all of the published results comparing East Asians and Caucasians show nearly all fragility fracture prevalences, including hip fracture, vertebral fracture, humerus fracture, and wrist fracture, are no more than half that of older Caucasians, both for men and women (reviewed in [7, 8], Fig. 1).
For Caucasian women (and men), the QCT lumbar spine (LS) BMD cutoff value for osteoporosis has been recommended to be 80 mg/ml [1, 13]. The same QCT criterion has also been commonly applied to East Asian populations [14,15,16,17,18,19]. With the proposed revision of the DXA LS T-score for East Asians in mind, in this article we discuss the most suitable QCT LS BMD cutpoint value for classifying osteoporosis among older East Asian women. Caucasian data will be used as reference, as the densitometric definition of osteoporosis was initially developed based on Caucasian fragility fracture profiles, and there are more validation studies available for Caucasians. We argue that an appropriate QCT LS BMD cutpoint value for classifying osteoporosis among older East Asian women is close to and no more than 50 mg/ml, which is substantially different from the value for Caucasians. Note that, for directly measured LS and hip DXA areal BMD, older East Asian women facture at a much lower BMD than that of Caucasians [7, 20].
Evidence supports a much lower QCT lumbar spine BMD threshold for classifying osteoporosis among older East Asian women than the value for Caucasians
The first line of evidence is based on population aging data. The population mean LS BMD and the related DXA T-score and QCT measure all decrease with age. Fig. 2 shows that, at the age of approximately 78 years, for US Caucasian women, the population mean LS T-score is -2.5 (i.e., the DXA cutpoint value for classifying osteoporosis), and if T-scores in this group are normally distributed, then half of them will have densitometric osteoporosis. At the same age, the LS T-score for Chinese women is -3.7 which is the recommended threshold to diagnose osteoporosis for Chinese women [7, 8]. By the age of 78 years, for US Caucasian women, the population mean QCT LS BMD is 77 mg/ml [21], consistent with the current QCT densitometric osteoporosis diagnosis threshold of 80 mg/ml. In contrast, for East Asian women at the same age, the QCT LS BMD has decreased to 54 g/ml (Fig. 2C) for Chinese women and 48 g/ml (Fig. 2D) for Japanese women, according to the data of Li et al. [14] and Fujii et al., respectively [22]. On the other hand, if a QCT LS BMD of 80 mg/ml is used as the cutpoint value to classify osteoporosis, then at the age of around 64 years, around half of the Chinese and Japanese female population of this age group will be classified as osteoporotic, which is known to be untrue [7, 8]. Note that, at the age of 78 years, the fragility fracture risk of Chinese and Japanese women is still lower than Caucasian women of the same age. Therefore, the data in Fig. 2 suggest that, for older East Asian women, the cutpoint for the QCT LS BMD definition of osteoporosis equivalent to the older Caucasian women’s threshold of 80 mg/ml is likely no more than 50 mg/ml.
The second line of evidence is based on the analyses demonstrated in Fig. 3. As shown in Fig. 3A, Lin et al. [15] compared QCT and DXA studies in 501 patients (395 females and 106 males, mean age: 71.3 and 67.6 years, respectively). Their data shows that 50 mg/ml QCT LS BMD corresponds to a DXA T-score of approximately of -3.3, whereas 80 mg/ml QCT LS BMD corresponds to a DXA T-score of approximately of -0.7. Note that we recommended cutpoint DXA T-score values for classifying osteoporosis of -3.7 for Chinese women and -3.2 for Chinese men. The data in Fig. 3B/C are from Yu et al. [23], who studied 24 women aged between 70–79 years using both LS QCT and DXA. The mean (± 1 SD) QCT BMD was 69.84 ± 20.14 mg/ml, and the DXA BMD was 0.912 ± 0.20 g/cm2. This study shows a value of 49.7 mg/ml (i.e., 69.84 minus 20.14) by QCT was equivalent to a value of 0.712 g/cm2 (i.e., 0.912 minus 0.20) by DXA. Following the Chinese BMD reference range study of Cheng et al. [24], we recommended that the DXA LS BMD threshold to diagnose osteoporosis is 0.674 g/cm2 [7, 8], which would be close to 45 QCT mg/ml. According to the results of Yu et al. shown in Fig. 3B/C, a QCT LS BMD of 80 mg/ml is equivalent to a DXA LS BMD > 1.0 g/cm2, well above the threshold for classifying osteoporosis using DXA [7]. Further supportive evidence comes from a study published by Uemura et al. [18]. They studied 59 patients (mean age: 66.3 years, 18 males, 41 females) with both LS QCT and DXA. Fig. 3D shows the plot of LS DXA BMD vs. QCT BMD. It demonstrates that a QCT BMD of approximately 45 mg/ml corresponds to a DXA BMD of around 0.7 mg/cm2, which is close to the cutpoint value for classifying osteoporosis [7]. Therefore, according to the data from these three studies, the QCT LS BMD threshold for diagnosing osteoporosis is likely to be 45 mg/ml.
The third line of evidence is that, for Chinese and Japanese, if a QCT LS BMD threshold of 80 mg/ml is used to classify osteoporosis, then the specificity of classifying subjects with vertebral fragility fracture (VFF) into the osteoporotic group is low (i.e., too many subjects without VFF will be classified into the osteoporotic group). Caucasian results for older populations have consistently shown that, in densitometrically osteoporotic women, the majority will have VFF while only a small proportion do not have VFF, whereas in densitometrically non-osteoporotic women, the majority do not have VFF while a small proportion have VFF. Fig. 4A shows data from a population-based study of Italian Caucasian women with a mean age of 74.1 years. If a DXA T-score ≤ -2.5 is used as the cutpoint value to classify osteoporosis, in the osteoporotic group, 86.2% of cases had VFF, while 38.8% of cases with VFF were in the non-osteoporotic group [25, 26]. In contrast, in Fig. 4B, if QCT LS BMD 80 mg/ml is used as the threshold to classify osteoporosis in the Chinese population-based study of Li et al. [14] (1304 males, mean age approximately 62.4 years; 2166 females, mean age approximately 61.5 years), 69.4% of osteoporotic cases did not have VFF, resulting in a very low specificity for VFF. Fig. 4C and D show two case–control studies for age-matched females with and without VFF from the UK and China, respectively. The UK women’s study (Fig. 4C, QCT LS BMD data shown as the mean and standard deviation, mean age: 68.9 years, assumed predominantly Caucasians) suggests that most of the subjects with VFF are in the QCT osteoporotic range, while most of the subjects without VFF are not in the osteoporotic range. The Chinese women’s study (Fig. 4D, QCT LS BMD data in mean and range, mean age: 68.0 years) suggests that, if the cutpoint value is < 80 mg/ml, a much higher portion of subjects without VFF are in the QCT osteoporotic range. A revision of the cutpoint value to 45 mg/ml would approximately achieve a similar separation of subjects with and without VFF as those shown in Fig. 4C, E, and F. Fig. 4E is a study of French Caucasian women, which demonstrates that 87.8% of the subjects with VFF are in the QCT osteoporotic range, while 12.2% are not in osteoporotic range. Fig. 4F is a study of a mixed-sex group of German men and women (assumed age: 70 years and predominantly Caucasians), where the majority (but not all) of the subjects with VFF are in the QCT osteoporotic range and the majority of the subjects without VFF are in the non-osteoporotic range. In Fig. 4G, if QCT LS 80 mg/ml is used as the cutpoint value to classify osteoporosis in Japanese women [22], then only 31.5% of cases in this osteoporosis group have VFF; if the cutpoint value is 45 mg/ml, then 88.8% of cases have VFF, which is more consistent with Caucasian data.
The fourth line of evidence is that, if 80 mg/ml is used as the cutpoint value, LS QCT leads to an excessively high prevalence of densitometric osteoporosis. In the Chinese population-based study of Li et al. [14] with 3420 community men and women aged > 40 years (characteristics described above, mean age around 62 years), the 80 mg/ml cutpoint value led to 28.5% of the study participants having osteoporosis, while only 33.2% had normal BMD (38.3% had osteopenia). In another Chinese study published by Li et al. [27], 140 postmenopausal women (age: 63.2 ± 8.1 years) underwent LS QCT and LS and hip DXA. The hip DXA-based osteoporosis prevalence was 12.9%, which can be reasonable [7]. However, the LS QCT-based osteoporosis prevalence was 46.4%, with the discordance between the hip DXA and LS QCT measures far exceeding expectations. Based on the initial WHO definition, the prevalence of densitometric osteoporosis is extrapolated from fragility fracture prevalence, and considering the relative low fragility fracture prevalence among Chinese women as compared with Caucasian women [4, 6, 7], the reported QCT osteoporosis prevalences in the above two studies were unreasonably high. In an analysis based on US data, Wright et al. [28] reported that DXA densitometric osteoporosis prevalence was 5.1%, 8.0%, 16.4%, and 26.2% for the age bands of 50–59 years, 60–69 years, 70–79 years, and ≥ 80 years of mixed gender and race, and the overall osteoporosis prevalence for Caucasian women (≥ 50 years) was 15.8%.
Discussion and conclusion
We admit that there are limitations to our arguments. With QCT, calibration precision, CT parameters, the use of single-slice QCT covering multiple vertebrae or volumetric measurement with spiral CT, region of interest (ROI) placement (which commonly includes trabecular bone while excluding cortex and vertebral posterior elements), etc. will all affect the final QCT reading. However, studies have demonstrated that the disagreements between various QCT measurements are usually minor [18, 29, 30]. The studies of Uemura et al. [18] and Yu et al. [23] are limited by their small sample sizes. The quality of data fitting for the study of Uemura et al. [18] is not optimal. The classification based on radiological VFF in Fig. 4 could be associated with reader subjectivity for milder VFF. Despite these limitations, the analyses in this article consistently show that the QCT LS BMD 80 mg/ml cutpoint value for classifying osteoporosis in East Asians is set too high. Instead, our analyses suggest that a more suitable cutpoint value would be closer to 45–50 mg/ml, though this article does not aim to propose a final cutpoint value. Since Chinese, Korean, and Japanese women have similar, though may not exactly the same, BMD and fragility fracture profiles [8, 31, 32], we believe the arguments in this article likely to be broadly applicable to older East Asian women. We suggest that it is also imperative that the QCT osteoporosis classification criterion for East Asian male LS and male and female hips be re-examined. For example, in one study of a convenient sample of Chinese male patients (n = 313; age: 79.6 ± 7.2 years) who had both LS QCT and LS and hip DXA measures, Xu et al. [33] reported that the hip DXA-based osteoporosis prevalence was 9.9%, whereas the LS QCT-based osteoporosis prevalence was 45.1%, with the discordance between the hip DXA and the LS QCT results also far exceeding expectation.
Earlier epidemiological studies frequently described the paradoxical phenomenon that ‘the densitometrical osteoporosis prevalence among Asians is high, but the FF prevalence among Asians is low’ [34,35,36]. For classifying osteoporosis prevalence among East Asians, it is essential to optimize a QCT BMD threshold based on ethnic-specific bone property and FF profile among East Asians. This will allow a more meaningful comparison of disease burden between East Asians and Caucasians and allow comparable medication intervention thresholds for East Asians and Caucasians. Considering the different bone properties and the much lower incidence of fragility fractures in the East Asian women compared with Caucasians, the most suitable QCT cutpoint value for classifying osteoporosis among older East Asian women is likely to be 45–50 mg/ml LS BMD.
References
Engelke K, Adams JE, Armbrecht G, Augat P, Bogado CE, Bouxsein ML, et al. Clinical use of quantitative computed tomography and peripheral quantitative computed tomography in the management of osteoporosis in adults: the 2007 ISCD Official Positions. J Clin Densitom. 2008;11:123–62.
Link TM, Lang TF. Axial QCT: clinical applications and new developments. J Clin Densitom. 2014;17:438–48.
Engelke K, Chaudry O, Bartenschlager S. Opportunistic screening techniques for analysis of CT scans. Curr Osteoporos Rep. 2023;21:65–76.
Wáng YXJ. Fragility fracture prevalence among elderly Chinese is no more than half of that of elderly Caucasians. Quant Imaging Med Surg. 2022;12:874–81.
Cong E, Walker MD. The Chinese skeleton: insights into microstructure that help to explain the epidemiology of fracture. Bone Res. 2014;2:14009.
Wáng YXJ, Guglielmi G, Guermazi A, Kwok TCY, Griffith JF. Much lower prevalence and severity of spine degenerative changes among older Chinese women than among older Caucasian women and its implication for the interpretation of lumbar spine BMD T-score for Chinese women. Skeletal Radiol. 2024;53(2):247–51.
Wáng YXJ, Xiao BH. Estimations of bone mineral density defined osteoporosis prevalence and cutpoint T-score for defining osteoporosis among older Chinese population: a framework based on relative fragility fracture risks. Quant Imaging Med Surg. 2022;12:4346–60.
Wáng YXJ, Griffith JF, Blake GM, Diacinti D, Xiao BH, Yu W, et al. Revision of the 1994 World Health Organization T-score definition of osteoporosis for use in older East Asian women and men to reconcile it with their lifetime risk of fragility fracture. Skeletal Radiol. 2024;53:609–25.
Walker MD, Liu XS, Zhou B, Agarwal S, Liu G, McMahon DJ, Bilezikian JP, Guo XE. Premenopausal and postmenopausal differences in bone microstructure and mechanical competence in Chinese-American and white women. J Bone Miner Res. 2013;28:1308–18.
Boutroy S, Walker MD, Liu XS, McMahon DJ, Liu G, Guo XE, Bilezikian JP. Lower cortical porosity and higher tissue mineral density in Chinese American versus white women. J Bone Miner Res. 2014;29:551–61.
Wáng YXJ, Deng M, Griffith JF, Kwok AWL, Leung JCS, Lam PMS, Yu BWM, Leung PC, Kwok TCY. “Healthier Chinese spine”: an update of osteoporotic fractures in men (MrOS) and in women (MsOS) Hong Kong spine radiograph studies. Quant Imaging Med Surg. 2022;12:2090–105.
Wáng YXJ, Diacinti D, Iannacone A, Kripa E, Leung JCS, Kwok TCY, Diacinti D. A comparison of radiographic degeneration features of older Chinese women and older Italian Caucasian women with a focus on thoracic spine. Aging Clin Exp Res. 2023;35:2583–91.
Expert Panel on Musculoskeletal Imaging, Yu JS, Krishna NG, Fox MG, Blankenbaker DG, Frick MA, Jawetz ST, et al. ACR appropriateness criteria osteoporosis and bone mineral density: 2022 Update. J Am Coll Radiol. 2022;19:S417–32.
Li K, Chen J, Zhao L, Chen Y, Zhou J, Shao J, et al. The establishment of QCT spinal vBMD reference database and the validation of the diagnosis criteria of osteoporosis with QCT for Chinese. Chin J Osteopros. 2019;25:1257–72.
Lin W, He C, Xie F, Chen T, Zheng G, Yin H, et al. Quantitative CT screening improved lumbar BMD evaluation in older patients compared to dual-energy X-ray absorptiometry. BMC Geriatr. 2023;23(1):231.
Nam KH, Seo I, Kim DH, Lee JI, Choi BK, Han IH. Machine learning model to predict osteoporotic spine with hounsfield units on lumbar computed tomography. J Korean Neurosurg Soc. 2019;62:442–9.
Lee JS, Kim K, Jeon YK, Kim J, Jung DH, Kim SH, et al. Effects of traction on interpretation of lumbar bone mineral density in patients with duchenne muscular dystrophy: a new measurement method and diagnostic criteria based on comparison of dual-energy x-ray absorptiometry and quantitative computed tomography. J Clin Densitom. 2020;23:53–62.
Uemura K, Fujimori T, Otake Y, Shimomoto Y, Kono S, Takashima K, et al. Development of a system to assess the two- and three-dimensional bone mineral density of the lumbar vertebrae from clinical quantitative CT images. Arch Osteoporos. 2023;18:22.
Cheng X, Wang L, Zeng Q, Wu J. Chinese guideline for the diagnosis of osteoporosis with quantitative computed tomography (2018). Chin J Health Manage. 2019;13:195–200.
Wáng YXJ, Blake GM, Xiao BH, Guglielmi G, Su Y, Jiang Y, Guermazi A, Kwok TCY, Griffith JF. East Asians’ T-scores for the diagnosis of osteoporosis should be calculated using ethnicity- and gender-specific BMD reference ranges: justifications. Skeletal Radiol. 2024;53:409–17.
Block JE, Smith R, Glueer CC, Steiger P, Ettinger B, Genant HK. Models of spinal trabecular bone loss as determined by quantitative computed tomography. J Bone Miner Res. 1989;4:249–57.
Fujii Y, Tsutsumi M, Tsunenari T, Fukase M, Yoshimoto Y, Fujita T, et al. Quantitative computed tomography of lumbar vertebrae in Japanese patients with osteoporosis. Bone Miner. 1989;6:87–94.
Yu W, Qin M, Xu L, van Kuijk C, Meng X, Xing X, et al. Normal changes in spinal bone mineral density in a Chinese population: assessment by quantitative computed tomography and dual-energy X-ray absorptiometry. Osteoporos Int. 1999;9(2):179–87.
Cheng XG, Yang DZ, Zhou Q, Zhuo TJ, Zhang HC, Xiang J, et al. Age-related bone mineral density, bone loss rate, prevalence of osteoporosis, and reference database of women at multiple centers in China. J Clin Densitom. 2007;10:276–84.
Wáng YXJ, Diacinti D, Leung JCS, Iannacone A, Kripa E, Kwok TCY, et al. Much lower prevalence and severity of radiographic osteoporotic vertebral fracture in elderly Hong Kong Chinese women than in age-matched Rome Caucasian women: a cross-sectional study. Arch Osteoporos. 2021;16:174.
Wáng YXJ, Diacinti D, Leung JCS, Iannacone A, Kripa E, Kwok TCY, et al. Conversion of osteoporotic vertebral fracture severity score to osteoporosis T-score equivalent status: a framework and a comparative study of Hong Kong Chinese and Rome Caucasian older women. Arch Osteoporos. 2022;18:1.
Li N, Li XM, Xu L, Sun WJ, Cheng XG, Tian W. Comparison of QCT and DXA: osteoporosis detection rates in postmenopausal women. Int J Endocrinol. 2013;2013:895474.
Wright NC, Looker AC, Saag KG, Curtis JR, Delzell ES, Randall S, et al. The recent prevalence of osteoporosis and low bone mass in the United States based on bone mineral density at the femoral neck or lumbar spine. J Bone Miner Res. 2014;29:2520–6.
Sollmann N, Loffler MT, El Husseini M, Sekuboyina A, Dieckmeyer M, Ruhling S, et al. Automated opportunistic osteoporosis screening in routine computed tomography of the spine: comparison with dedicated quantitative CT. J Bone Miner Res. 2022;37:1287–96.
Steiger P, Block JE, Steiger S, Heuck AF, Friedlander A, Ettinger B, et al. Spinal bone mineral density measured with quantitative CT: effect of region of interest, vertebral level, and technique. Radiology. 1990;175:537–43.
Lo JC, Chandra M, Lee C, Darbinian JA, Ramaswamy M, Ettinger B. Bone mineral density in Older U.S. Filipino, Chinese, Japanese, and White women. J Am Geriatr Soc. 2020;68:2656–61.
Shin MH, Zmuda JM, Barrett-Connor E, Sheu Y, Patrick AL, Leung PC, et al. Race/ethnic differences in associations between bone mineral density and fracture history in older men. Osteoporos Int. 2014;25:837–45.
Xu XM, Li N, Li K, Li XY, Zhang P, Xuan YJ, Cheng XG. Discordance in diagnosis of osteoporosis by quantitative computed tomography and dual-energy X-ray absorptiometry in Chinese elderly men. J Orthop Translat. 2018;18:59–64.
Siris ES, Miller PD, Barrett-Connor E, Faulkner KG, Wehren LE, Abbott TA, et al. Identification and fracture outcomes of undiagnosed low bone mineral density in postmenopausal women: results from the National Osteoporosis Risk Assessment. JAMA. 2001;286:2815–22.
Lo JC, Kim S, Chandra M, Ettinger B. Applying ethnic-specific bone mineral density T-scores to Chinese women in the USA. Osteoporos Int. 2016;27:3477–84.
Noel SE, Santos MP, Wright NC. Racial and Ethnic Disparities in Bone Health and Outcomes in the United States. J Bone Miner Res. 2021;36:1881–905.
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The authors thank colleagues at Shunde Hospital, Guangdong, China, for their explanation of the DXA procedure used in reference [15] (Lin et al.).
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Wáng, Y.X.J., Blake, G.M., Tang, SN. et al. Quantitative CT lumbar spine BMD cutpoint value for classifying osteoporosis among older East Asian women should be lower than the value for Caucasians. Skeletal Radiol (2024). https://doi.org/10.1007/s00256-024-04632-4
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DOI: https://doi.org/10.1007/s00256-024-04632-4