Department of Surgical Sciences, Unit of Medical Epidemiology, Uppsala University, Uppsala, Sweden.
Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
J Bone Miner Res. 2021 Jul;36(7):1288-1299. doi: 10.1002/jbmr.4298. Epub 2021 May 4.
We aimed to comprehensively evaluate the association of body composition with fracture risk using longitudinal data from a Swedish cohort of 44,366 women and men (mean age of 70 years) and a subcohort of 5022 women. We estimated hazard ratios (HRs) of fracture for baseline body mass index (BMI), BMI change during the prior 12 and 18 years, baseline waist-to-height ratio, total and regional distribution of fat and lean mass, with and without areal bone mineral density (BMD) adjustment. During follow-up (median 8.7 years), 7290 individuals sustained a fracture, including 4279 fragility fractures, of which 1813 were hip fractures. Higher baseline BMI and prior gain in BMI were inversely associated with all types of fracture. Lower fracture rate with higher baseline BMI was seen within every category of prior BMI change, whereas higher prior BMI gain conferred a lower rate of fracture within those with normal baseline BMI. Each standard deviation (SD) higher baseline waist-to-height ratio, after adjustment for BMI, was associated with higher rates of hip fracture in both women and men (HR 1.12; 95% CI, 1.05-1.19). In the subcohort (median follow-up 10 years), higher baseline fat mass index (FMI) and appendicular lean mass index (LMI) showed fracture-protective effects. After BMD adjustment, higher baseline BMI, total LMI, FMI, and higher prior BMI gain were associated with higher fracture rate. Baseline fat distribution also was associated with fracture rate; a 1-SD higher android to gynoid fat mass ratio in prior BMI gainers was associated with BMD-adjusted HRs of 1.16 (95% CI, 1.05-1.28) for any fracture and 1.48 (95% CI, 1.16-1.89) for hip fracture. This pattern was not observed among prior BMI losers. These findings indicate that for optimal fracture prevention, low baseline BMI, prior BMI loss and high baseline central obesity should be avoided in both women and men. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
我们旨在利用来自瑞典 44366 名女性和男性（平均年龄为 70 岁）的队列和 5022 名女性的亚队列的纵向数据，全面评估身体成分与骨折风险的关系。我们估计了基线体重指数 (BMI)、前 12 年和 18 年 BMI 变化、基线腰高比、脂肪和瘦体重的总分布和区域分布的骨折风险比 (HR)，并调整了和未调整面积骨密度 (BMD)。在随访期间（中位数为 8.7 年），7290 人发生了骨折，其中 4279 人发生了脆性骨折，1813 人发生了髋部骨折。较高的基线 BMI 和之前 BMI 的增加与所有类型的骨折呈负相关。在每个 BMI 变化的类别中，都可以观察到较高的基线 BMI 与较低的骨折率相关，而较高的 BMI 增加则在那些基线 BMI 正常的人群中与较低的骨折率相关。在调整 BMI 后，较高的基线腰高比与女性和男性的髋部骨折发生率升高相关（HR 1.12；95%CI，1.05-1.19）。在亚队列中（中位随访 10 年），较高的基线脂肪量指数 (FMI) 和四肢瘦体重指数 (LMI) 显示出骨折保护作用。在调整 BMD 后，较高的基线 BMI、总 LMI、FMI 和较高的 BMI 增加与较高的骨折率相关。基线脂肪分布也与骨折率相关；在 BMI 增加者中，1-SD 较高的腹部到臀部脂肪质量比与 BMD 调整后的任何骨折 HR 为 1.16（95%CI，1.05-1.28）和髋部骨折 HR 为 1.48（95%CI，1.16-1.89）相关。这种模式在 BMI 减少者中没有观察到。这些发现表明，为了达到最佳的骨折预防效果，女性和男性都应避免低基线 BMI、先前的 BMI 损失和高基线中心性肥胖。
