Given non-optimal testing rates for dual-energy X-ray absorptiometry (DXA) and the high use of computed tomography (CT) in some Asian countries, biomechanical computed tomography analysis (BCT)-based bone strength testing, which utilizes previously taken clinical CT scans, may improve osteoporosis testing rates. However, an understanding of ethnic differences in such bone strength measurements between Whites and Asians is lacking, which is an obstacle to clinical interpretation. Using previously taken CT and DXA scans, we analyzed bone strength and bone mineral density (BMD) at the hip and spine in two sex- and age-matched community-based cohorts, aged 40 to 80 years: Whites (Rochester, MN, USA) and Koreans (Seoul, South Korea). For both the spine and femur, the age dependence of bone strength was similar for both groups, White (n = 371; women n = 202, 54.5%) and Korean (n = 396; women n = 199, 50.3%). For both sexes, mean spine strength did not differ between groups, but femur strength was 9% to 14% higher in Whites (p ≤ 0.001), an effect that became non-significant after weight adjustment (p = 0.375). For Koreans of both sexes, the fragile bone strength thresholds for classifying osteoporosis, when derived from regional DXA BMD T-score references, equaled the clinically validated thresholds for Whites (in women and men, femoral strength, 3000 N and 3500 N; vertebral strength 4500 N and 6500 N, respectively). Using these thresholds, classifications for osteoporosis for Koreans based on bone strength versus based on DXA BMD T-scores were consistent (89.1% to 94.4% agreement) at both the hip and spine and for both sexes. The BCT-based, clinically validated bone strength thresholds for Whites also applied to Koreans, which may facilitate clinical interpretation of CT-based bone strength measurements for Koreans.
Bibliographical noteFunding Information:
This study was funded by Amgen's Investigator Sponsored Studies Program (ISS; reference number 20177243) and by NIH grant AR027065 (SK). We thank the members of the Severance Health Checkup Center for providing access to the database of participants. We also thank Minheui Yoo, MS, and Doori Cho from the SENTINEL (Severance Endocrinology Data Science Platform) program (4-2018-1215; DUCD000002) of the Endocrinology Division, Department of Internal medicine, Yonsei University College of Medicine, Seoul, Korea, for assisting with statistical analysis. Authors' roles: Study design: NH, YR, and TMK. Study conduct: NH, DCL, TMK, and YR. Data collection: NH, SK, DCL, TMK, and YR. Data analysis: NH and DCL. Data interpretation: all authors. Drafting manuscript: NH and DCL. Revising manuscript content: all authors. Approving final version of manuscript: all authors. All authors take responsibility for the integrity of the data analysis.
All Science Journal Classification (ASJC) codes
- Endocrinology, Diabetes and Metabolism
- Orthopedics and Sports Medicine