Faculty of Sport and Health Sciences and Gerontology Research Center, University of Jyväskylä, Jyväskylä, Finland.
Center of Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Geroscience. 2024 Apr;46(2):1575-1588. doi: 10.1007/s11357-023-00925-z. Epub 2023 Sep 1.
Reduced age-specific mortality and increased muscle strength and walking speed of current older adults may have altered the relationships between these factors as more people may be above the reserve capacity threshold. We compared the cross-sectional associations between muscle strength and walking speed, and the associations of muscle strength and walking speed with five-year mortality between two population-based cohorts of 75- and 80-year-old people born 28 years apart. Maximal isometric grip and knee extension strength and walking speed were measured in 2017-2018 (n = 726). Mortality was ascertained from registers. The associations were compared with data of same-aged people studied in 1989-1990 with identical protocols (n = 500). The knee extension strength-walking speed relationship showed plateauing at higher strength levels among the later-born men, whereas the earlier-born men and women of both cohorts with lower strength levels were on the linear part of the curve. In the later-born women with lower five-year mortality rate (1.16 vs. 5.88 per 100 person-years), the association between grip strength and mortality was markedly different from the earlier cohort (HR 1.13 [95% CI 0.47-2.70] vs. 0.57 [0.37-0.86]). For knee extension strength and walking speed, the mortality hazards were similar between the cohorts, although statistically non-significant in the later-born women. In men, the later-born cohort showed similar associations as observed in the earlier-born cohort despite having lower mortality rate (2.93 vs. 6.44). Current older adults have more functional reserve that will likely help them to maintain walking ability for longer while also contributing to better survival.
当前老年人的年龄特异性死亡率降低，肌肉力量和行走速度增加，这可能改变了这些因素之间的关系，因为更多的人可能超过储备能力阈值。我们比较了两个基于人群的 75 岁和 80 岁队列中肌肉力量和行走速度之间的横断面关联，以及肌肉力量和行走速度与五年死亡率之间的关联，这两个队列的参与者出生时间相差 28 年。在 2017-2018 年测量了最大等长握力和膝关节伸展力量以及行走速度（n=726）。死亡率是从登记处确定的。将这些关联与 1989-1990 年使用相同方案研究的同年龄组人群的数据进行了比较（n=500）。在后来出生的男性中，膝关节伸展力量-行走速度关系在较高的力量水平上显示出趋于平稳，而两个队列中较低力量水平的较早出生的男性和女性则处于曲线的线性部分。在较低五年死亡率（1.16 与 5.88/100 人年）的后来出生女性中，握力与死亡率之间的关联与较早队列明显不同（HR 1.13 [95%CI 0.47-2.70] 与 0.57 [0.37-0.86]）。对于膝关节伸展力量和行走速度，死亡率风险在队列之间相似，尽管在后来出生的女性中统计学上无显著性。在男性中，尽管死亡率较低（2.93 与 6.44），但后来出生的队列表现出与较早出生的队列相似的关联。当前的老年人具有更多的功能储备，这可能有助于他们在更长时间内保持行走能力，同时也有助于更好的生存。
