Gordon Catherine M, Fleisch Abby F, Hivert Marie-France, Rokoff Lisa B, Rifas-Shiman Sheryl L, Raphael Jean L, Oken Emily
Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA.
Center for Interdisciplinary Population and Health Research, MaineHealth Institute for Research, Portland, ME, USA.
Pediatr Res. 2024 Oct 17. doi: 10.1038/s41390-024-03588-4.
Dual-energy x-ray absorptiometry reference data designate Black and non-Black categories, as higher BMD has been documented among Black youth. We examined associations of race, skin tone, and genetic factors with bone mineral density (BMD).
557 adolescents were followed longitudinally. Exposures included race, skin tone, and principal components (PC) from genome-wide arrays. Total body BMD Z-score (BMD-Z) was the primary outcome using linear regression.
359 adolescents identified as non-Hispanic White (NHW) and 75, non-Hispanic Black (NHB). BMD-Z was higher in NHB vs. NHW (β: 0.92 units, 95% CI: 0.64, 1.19) or those with darker skin (0.79, 95% CI: 0.49, 1.08 for brown vs. medium). The first genetic PC (PC1) correlated with identification as NHB. PC1 was associated with higher BMD-Z (0.09, 95% CI: 0.06, 0.12), even after including race (0.07, 95% CI: 0.00, 0.14) or skin tone (0.10, 95% CI: 0.05, 0.15); both race (0.26, 95% CI: -0.49, 1.01 for NHB vs. NHW) and skin tone (-0.08, 95% CI: -0.59, 0.44 for brown vs. medium) no longer predicted BMD-Z after adjustment for PC1.
Genetic similarity was robustly associated with BMD, prompting a reevaluation of adolescent BMD reference data to exclude the consideration of race.
Current bone density reference databases include a binary assignment of patients into "Black" and "non-Black" categories, as a higher BMD has been documented among those identifying as Black compared with individuals of other racial and ethnic backgrounds. This study found genetic similarity to be more strongly associated with bone density by dual-energy x-ray absorptiometry than race or skin tone. These data emphasize a need to reevaluate how bone density measurements are interpreted, including exploring reference data that exclude the consideration of race.
双能X线吸收法参考数据将人群分为黑人与非黑人两类，因为有记录表明黑人青少年的骨密度较高。我们研究了种族、肤色和遗传因素与骨矿物质密度（BMD）之间的关联。
对557名青少年进行纵向跟踪研究。暴露因素包括种族、肤色以及全基因组阵列的主成分（PC）。采用线性回归分析，将全身骨密度Z值（BMD-Z）作为主要研究指标。
359名青少年被认定为非西班牙裔白人（NHW），75名被认定为非西班牙裔黑人（NHB）。与NHW相比，NHB的BMD-Z更高（β：0.92个单位，95%置信区间：0.64，1.19），肤色较深者的BMD-Z也更高（棕色皮肤与中等肤色相比，β为0.79，95%置信区间：0.49，1.08）。第一个遗传主成分（PC1）与被认定为NHB相关。PC1与较高的BMD-Z相关（β为0.09，95%置信区间：0.06，0.12），即使纳入种族因素（β为0.07，95%置信区间：0.00，0.14）或肤色因素（β为0.10，95%置信区间：0.05，0.15）后依然如此；在对PC1进行校正后，种族（NHB与NHW相比，β为0.26，95%置信区间：-0.49，1.01）和肤色（棕色皮肤与中等肤色相比，β为-0.08，95%置信区间：-0.59，0.44）均不再能预测BMD-Z。
遗传相似性与骨密度密切相关，这促使我们重新评估青少年骨密度参考数据，以排除对种族因素的考量。
目前的骨密度参考数据库将患者分为“黑人”和“非黑人”两类，因为有记录显示，与其他种族和族裔背景的个体相比，黑人的骨密度较高。本研究发现，通过双能X线吸收法测量，遗传相似性与骨密度的关联比种族或肤色更强。这些数据强调有必要重新评估骨密度测量结果的解读方式，包括探索排除种族因素考量的参考数据。
