Baseline characteristics of study participants.

BackgroundOsteoporosis is a skeletal disorder characterized by reduced bone mass and increased fracture risk. With the aging global population, its prevalence is rising, posing a significant public health challenge. Physical activity is considered an effective intervention to reduce osteoporosis risk, but the role of grip strength as a mediator remains underexplored.MethodsData from the English Longitudinal Study of Ageing (ELSA) and the Health and Retirement Study (HRS) were analyzed using generalized linear mixed models (GLMM) and mediation analysis to explore the impact of physical activity on osteoporosis and the role of grip strength. Subgroup analyses accounted for age, gender, and confounding factors.ResultsThe prevalence of osteoporosis was 6.3% in ELSA and 14.1% in HRS. A significant negative correlation was found between physical activity and osteoporosis in both groups (ELSA: OR = 0.234, P P = 0.028). In those aged ≥65, physical activity had a more pronounced effect (OR = 0.478, P ConclusionPhysical activity, especially resistance training, reduces osteoporosis incidence by enhancing muscle strength, with grip strength playing a mediating role. These findings highlight the importance of physical activity, particularly in older women, for osteoporosis prevention.

背景 骨质疏松症（Osteoporosis）是一种以骨量减少与骨折风险升高为特征的骨骼疾病。随着全球人口老龄化进程加快，其患病率持续上升，已构成严峻的公共卫生挑战。尽管体力活动被认为是降低骨质疏松发病风险的有效干预手段，但握力作为中介变量的作用仍未得到充分探索。方法 本研究采用广义线性混合模型（Generalized Linear Mixed Models, GLMM）与中介分析方法，对英国老龄化纵向研究（English Longitudinal Study of Ageing, ELSA）及健康与退休研究（Health and Retirement Study, HRS）的数据进行分析，以探究体力活动对骨质疏松的影响及握力的中介作用。亚组分析纳入年龄、性别及混杂因素进行考量。结果 ELSA队列的骨质疏松患病率为6.3%，HRS队列则为14.1%。两项队列均显示体力活动与骨质疏松呈显著负相关（ELSA：OR=0.234，P=0.028）。在年龄≥65岁的人群中，体力活动的保护效应更为显著（OR=0.478，P）。结论 体力活动，尤其是抗阻训练，可通过增强肌肉力量降低骨质疏松的发病风险，其中握力发挥了中介作用。本研究结果凸显了体力活动，尤其针对老年女性，在骨质疏松预防中的重要价值。