Kirk Ben, Harrison Stephanie L, Zanker Jesse, Burghardt Andrew J, Orwoll Eric, Cawthon Peggy M, Duque Gustavo
The University of Melbourne Melbourne Medical School, Department of Medicine-Western Health, Melbourne, Victoria, Australia.
The University of Melbourne Western Clinical School at Sunshine Hospital, Australian Institute for Musculoskeletal Science (AIMSS), Saint Albans, Victoria, Australia.
Age Ageing. 2025 Jul 1;54(7). doi: 10.1093/ageing/afaf189.
Low bone density and low muscle mass are both independent risk factors for mortality in older men. However, it is unknown if these tissues interact to increase mortality risk. Elucidating this information is important as bone and muscle are modifiable across the life cycle.
To examine whether there is an interconnection between bone density and muscle mass on all-cause mortality in older men.
Prospective cohort study.
The Osteoporotic Fractures in Men study, an multicenter longitudinal study across six US sites.
Exposures measured at baseline visit (2014-2016) included bone density by dual-energy X-ray absorptiometry (hip, g/cm2); muscle mass by creatine dilution stable isotope (whole body, kg); bone strength by high-resolution computed tomography (tibia, newtons); and muscle volume by high-resolution computed tomography (calf, mm3). Covariates measured at baseline visit (2014-2016) included demographics and lifestyle factors as well as medical conditions.
All-cause mortality by death certificates and International Classification of Diseases-Ninth Revision codes measured from 2014 to 2016 through August 2024. Data analysis was performed during December 2024. Cox hazards models were used to model the relationship between the exposures and outcomes, unadjusted and adjusted for covariates.
A total of 1388 men with a mean age of 84.2 ± 4.1 years (77-101 years, 91.6% white) were followed for 6.58 ± 2.61 years. A total of 663 (47.8%) men died. In unadjusted analyses using continuous exposures, interaction terms were significant between bone and muscle variables for all-cause mortality (P < 0.001 to 0.039). In men with low muscle mass or low muscle volume (≤50th percentile), each SD decrease in bone density increased all-cause mortality by a respective 19% (HR = 1.19 95% CI 1.07-1.34) and 29% (HR = 1.29 95% CI 1.11-1.49) in multivariable-adjusted models. Likewise, in men with low muscle mass or low muscle volume (≤50th percentile), each SD decrease in bone strength increased all-cause mortality by a respective 19% (HR = 1.19 95% CI 1.06-1.33) and 29% (HR = 1.29 95% CI 1.12-1.48) in multivariable-adjusted models.
We found consistent evidence for a combined association of bone and muscle health on all-cause mortality. Randomised controlled trials are now needed to confirm if increasing or preserving bone and muscle mass in old age reduces mortality risk.
低骨密度和低肌肉量都是老年男性死亡的独立危险因素。然而，尚不清楚这些组织之间是否相互作用以增加死亡风险。阐明这一信息很重要，因为骨骼和肌肉在整个生命周期中都是可改变的。
研究老年男性骨密度和肌肉量与全因死亡率之间是否存在关联。
前瞻性队列研究。
男性骨质疏松性骨折研究，一项在美国六个地点进行的多中心纵向研究。
在基线访视（2014 - 2016年）时测量的暴露因素包括通过双能X线吸收法测量的骨密度（髋部，g/cm²）；通过肌酸稀释稳定同位素测量的肌肉量（全身，kg）；通过高分辨率计算机断层扫描测量的骨强度（胫骨，牛顿）；以及通过高分辨率计算机断层扫描测量的肌肉体积（小腿，mm³）。在基线访视（2014 - 2016年）时测量的协变量包括人口统计学和生活方式因素以及医疗状况。
通过死亡证明和国际疾病分类第九版编码测量的2014年至2016年直至2024年8月的全因死亡率。数据分析于2024年12月进行。使用Cox风险模型对暴露因素与结局之间的关系进行建模，未调整以及针对协变量进行调整。
共有1388名男性，平均年龄为84.2±4.1岁（77 - 101岁，91.6%为白人），随访6.58±2.61年。共有663名（47.8%）男性死亡。在使用连续暴露因素的未调整分析中，骨和肌肉变量之间的交互项对于全因死亡率具有显著意义（P < 0.001至0.039）。在肌肉量低或肌肉体积低（≤第50百分位数）的男性中，在多变量调整模型中，骨密度每降低1个标准差，全因死亡率分别增加19%（风险比[HR]=1.19，95%置信区间[CI] 1.07 - 1.34）和29%（HR = 1.29，95% CI 1.11 - 1.49）。同样，在肌肉量低或肌肉体积低（≤第50百分位数）的男性中，在多变量调整模型中，骨强度每降低1个标准差，全因死亡率分别增加19%（HR = 1.19，95% CI 1.06 - 1.33）和29%（HR = 1.29，95% CI 1.12 - 1.48）。
我们发现了骨骼和肌肉健康与全因死亡率联合关联的一致证据。现在需要进行随机对照试验来确认在老年时增加或保持骨骼和肌肉量是否能降低死亡风险。
