Wang Zhi-Zhuang, Ma Guo-Liang, Xu Bo, Chen Xin, Yang Bo-Wen, Qin Xiao-Kuan, Duan Wei-Li, Feng Min-Shan, Yin He, Sun Kai, Zhu Li-Guo
Department of Spine, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing, China.
Nanyang Hospital, Wangjing Hospital, Chinese Academy of Traditional Chinese Medicine (Dushan Hospital District), Henan, China.
Front Endocrinol (Lausanne). 2025 Apr 7;16:1506841. doi: 10.3389/fendo.2025.1506841. eCollection 2025.
Despite accumulating evidence on central obesity and osteoporosis, the role of a body shape index (ABSI), a nonlinear index quantifying body shape via body mass index (BMI), waist circumference (WC), and height, remains controversial and underexplored. Although recent meta-analyses suggest central obesity may modulate fracture risk bidirectionally, no research has comprehensively compared ABSI with traditional adiposity metrics, such as BMI, WC, and waist-to-height ratio (WHtR), to predict site-specific changes in bone mineral density (BMD) across anatomical regions.
This study utilized National Health and Nutrition Examination Survey (NHANES) data from 2005 to 2018, involving 12,421 participants. ABSI was computed using the formula: ABSI = WC/(BMI²/³ × Height¹/²). BMD was assessed at four sites-the total femur (TF), femoral neck (FN), trochanter (TR), and intertrochanter (IN) regions-via dual-energy X-ray absorptiometry (DXA). The association between ABSI and BMD was analyzed via multiple regression models and a generalized additive model (GAM). To compare ABSI's predictive efficacy with conventional adiposity indices, regression analyses juxtaposed ABSI against BMI, WC, and WHtR in assessing correlations with site-specific BMD.
After full covariate adjustment, a significant negative association was observed between ABSI and BMD in four femoral regions (< 0.01). Smoothed curve fitting revealed a significant nonlinear relationship and threshold effect between ABSI and BMD among middle-aged and older individuals. Additionally, an inverted J-shaped curve was observed between ABSI and BMD in all four femoral regions. Meanwhile, ABSI showed significant negative associations with BMD across all femoral sites (β = -0.27 to -0.31, -trend< 0.000001), whereas BMI, WC, and WHtR exhibited positive correlations (WHtR showing the strongest effect: β = 0.41-0.69). This highlights ABSI's ability to detect central adiposity-related bone loss obscured by conventional obesity metrics.
ABSI's robust inverse associations with femoral BMD (β = -0.27 to -0.31), persisting across nonlinear threshold analyses, establish it as a novel biomarker of central adiposity-related skeletal fragility. Unlike conventional indices reflecting mechanical loading benefits (BMI β = 0.008-0.012; WC β = 0.003-0.005; WHtR β = 0.41-0.69), ABSI specifically captures visceral fat-driven metabolic disorder-a critical pathway for osteoporosis risk stratification in normal-weight and obese populations.
尽管关于中心性肥胖和骨质疏松症的证据不断积累，但身体形状指数（ABSI）的作用仍存在争议且未得到充分研究。ABSI是一种通过体重指数（BMI）、腰围（WC）和身高来量化身体形状的非线性指数。尽管最近的荟萃分析表明中心性肥胖可能双向调节骨折风险，但尚无研究全面比较ABSI与传统肥胖指标，如BMI、WC和腰高比（WHtR），以预测不同解剖区域骨矿物质密度（BMD）的部位特异性变化。
本研究利用了2005年至2018年的美国国家健康与营养检查调查（NHANES）数据，涉及12421名参与者。ABSI使用公式计算：ABSI = WC /（BMI²/³×身高¹/²）。通过双能X线吸收法（DXA）在四个部位评估BMD，即全股骨（TF）、股骨颈（FN）、大转子（TR）和转子间（IN）区域。通过多元回归模型和广义相加模型（GAM）分析ABSI与BMD之间的关联。为了比较ABSI与传统肥胖指数的预测效果，在评估与部位特异性BMD的相关性时，回归分析将ABSI与BMI、WC和WHtR并列比较。
在进行全面协变量调整后，在四个股骨区域观察到ABSI与BMD之间存在显著的负相关（<0.01）。平滑曲线拟合显示中年及老年个体中ABSI与BMD之间存在显著的非线性关系和阈值效应。此外，在所有四个股骨区域观察到ABSI与BMD之间呈倒J形曲线。同时，ABSI在所有股骨部位与BMD均呈显著负相关（β = -0.27至-0.31，-趋势<0.000001），而BMI、WC和WHtR呈正相关（WHtR显示最强效应：β = 0.41 - 0.69）。这突出了ABSI检测传统肥胖指标所掩盖的与中心性肥胖相关的骨质流失的能力。
ABSI与股骨BMD之间存在稳健的负相关（β = -0.27至-0.31），在非线性阈值分析中持续存在，这使其成为与中心性肥胖相关的骨骼脆弱性的新型生物标志物。与反映机械负荷益处的传统指标不同（BMI β = 0.008 - 0.012；WC β = 0.003 - 0.005；WHtR β = 0.41 - 0.69），ABSI专门捕捉内脏脂肪驱动的代谢紊乱，这是正常体重和肥胖人群骨质疏松症风险分层的关键途径。
