Department of Hygiene and Public Health, Osaka Medical College, 2-7 Daigakumachi, Takatsuki City, Osaka 569-8686, Japan.
Arch Gerontol Geriatr. 2012 Mar-Apr;54(2):e230-3. doi: 10.1016/j.archger.2011.06.015. Epub 2011 Aug 9.
This study describes the association between low muscle mass and disability in performing IADL in elderly, community-dwelling Japanese subjects. Subjects were 1268 elderly, community-dwelling Japanese aged 65 years or older. Low muscle mass was defined by appendicular muscle mass index (AMI, weight [kg]/height [m(2)]), measured by bioelectrical impedance analysis (BIA). We classified "middle" AMI as a value 1-2 standard deviation (SD) below the young normal mean of AMI and "low" as more than 2 SD below the young normal mean. Examination of IADL was performed using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) questionnaire. In this study, 17.2% and 26.2% of elderly men and women, respectively, were classified as having low muscle mass. There was a significant association with age and the change from normal to middle to low muscle mass in both men and women. The prevalence of IADL disability also increased significantly as muscle mass decreased. After adjustment for age and BMI, low muscle mass was significantly associated with IADL disability in men and women. Furthermore, middle muscle mass was significantly associated with IADL disability in women. This study revealed that low muscle mass, defined as a value 2 SD below the mean of young adults, had a significant association with IADL disability in elderly Japanese. Interventions to prevent age-related losses in muscle mass may be an effective strategy to prevent IADL disability among the elderly.
本研究描述了在日本社区居住的老年人群中，低肌肉量与进行日常生活活动能力（IADL）障碍之间的关系。研究对象为 1268 名年龄在 65 岁及以上的日本社区居住的老年人。通过生物电阻抗分析（BIA）测量四肢肌肉质量指数（AMI，体重[kg]/身高[m(2)]）来定义低肌肉量。我们将“中等”AMI 定义为低于年轻正常 AMI 平均值 1-2 个标准差（SD）的值，而“低”则定义为低于年轻正常 AMI 平均值 2 个 SD 以上的值。使用东京都立老人综合研究所能力指数（TMIG-IC）问卷对 IADL 进行检查。在这项研究中，分别有 17.2%和 26.2%的老年男性和女性被归类为低肌肉量。无论男性还是女性，随着年龄的增长以及从正常到中等再到低肌肉量的变化，都与肌肉量显著相关。IADL 障碍的患病率也随着肌肉量的减少而显著增加。在调整年龄和 BMI 后，低肌肉量与男性和女性的 IADL 障碍显著相关。此外，中等肌肉量与女性的 IADL 障碍显著相关。本研究表明，低肌肉量（定义为低于年轻成年人平均值 2 SD）与日本老年人群的 IADL 障碍显著相关。预防与年龄相关的肌肉量损失的干预措施可能是预防老年人 IADL 障碍的有效策略。
