Zhu Xiao-Wei, Liu Ke-Qi, Yuan Cheng-Da, Xia Jiang-Wei, Qian Yu, Xu Lin, Gao Jian-Hua, Rong Xiao-Li, Chen Guo-Bo, Karasik David, Xie Shu-Yang, Zheng Hou-Feng
Fudan University, Shanghai 200433, China.
Diseases & Population (DaP) Geninfo Lab, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China.
iScience. 2022 May 25;25(6):104466. doi: 10.1016/j.isci.2022.104466. eCollection 2022 Jun 17.
To infer the causality between obesity and fracture and the difference between general and abdominal obesity, a prospective study was performed in 456,921 participants, and 10,142 participants developed an incident fracture with follow-up period of 7.96 years. A U-shape relationship was observed between BMI and fracture, with the lowest risk of fracture in overweight participants. The obesity individuals had higher fracture risk when BMD was adjusted, and the protective effect of moderate-high BMI on fracture was mostly mediated by bone mineral density (BMD). However, for abdominal obesity, the higher WCadjBMI (linear) and HCadjBMI (J-shape) were found to be related to higher fracture risk, and less than 30% of the effect was mediated by BMD. By leveraging genetic instrumental variables, it provided additional evidences to support the aforementioned findings. In conclusion, keeping moderate-high BMI might be of benefit to old people in terms of fracture risk, whereas abdominal adiposity might increase risk of fracture.
为了推断肥胖与骨折之间的因果关系以及全身肥胖与腹型肥胖之间的差异，对456,921名参与者进行了一项前瞻性研究，在7.96年的随访期内，有10,142名参与者发生了新发骨折。观察到体重指数（BMI）与骨折之间呈U形关系，超重参与者的骨折风险最低。调整骨密度（BMD）后，肥胖个体的骨折风险更高，中高BMI对骨折的保护作用主要由骨密度介导。然而，对于腹型肥胖，较高的校正腰围体重指数（WCadjBMI，呈线性）和校正臀围体重指数（HCadjBMI，呈J形）与较高的骨折风险相关，且不到30%的影响由BMD介导。通过利用基因工具变量，为上述发现提供了额外证据。总之，保持中高BMI可能对老年人的骨折风险有益，而腹部肥胖可能会增加骨折风险。
