Doi Takehiko, Shimada Hiroyuki, Makizako Hyuma, Tsutsumimoto Kota, Hotta Ryo, Nakakubo Sho, Suzuki Takao
Department of Functioning Activation, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan. Japan Society for the Promotion of Science, Tokyo, Japan. Research Institute, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
Department of Functioning Activation, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
J Gerontol A Biol Sci Med Sci. 2016 Jun;71(6):797-802. doi: 10.1093/gerona/glv167. Epub 2015 Sep 30.
Disability is a crucial health problem in aging. Identifying a biological contributory factor would be useful. Serum insulin-like growth factor-1 (IGF-1) plays an important role in the endocrine system and is associated with frailty. However, there is no consensus about the relationship between IGF-1 and disability. This study aimed to examine whether IGF-1 related to incident disability among older adults.
The study included 4,133 older adults (mean age, 71.8±5.4 years) who were participants in the "Obu Study of Health Promotion for the Elderly" cohort study. We collected information on demographic variables, measured gait speed, Mini Mental State Examination score, and serum IGF-1 at baseline. During follow-up, incident disability was monitored by Long-Term Care Insurance certification.
Disability was observed in 212 participants during a mean follow-up duration period of 29.2 months. A log rank test indicated that lower levels of serum IGF-1 were related to incident disability (p = .004). A Cox hazard regression showed a lower quartile in IGF-1 related to disability compared with the highest quartile (Q4), even when adjusting for covariates including gait speed and Mini Mental State Examination score (Q1: hazard ratio = 1.72, 95% confidence intervals: 1.06-2.81; Q2: hazard ratio = 1.64, 95% confidence intervals: 0.99-2.71; Q3: hazard ratio = 1.31, 95% confidence intervals: 0.76-2.25). In the analysis, stratified by sex, there was also significant relationship between IGF-1 and disability among women, but not men.
Lower serum IGF-1 was independently related to disability among older adults.
残疾是老龄化过程中的一个关键健康问题。确定一个生物学促成因素将很有帮助。血清胰岛素样生长因子-1（IGF-1）在内分泌系统中起重要作用，且与身体虚弱相关。然而，关于IGF-1与残疾之间的关系尚无共识。本研究旨在探讨IGF-1是否与老年人发生残疾有关。
该研究纳入了4133名老年人（平均年龄71.8±5.4岁），他们是“大府老年人健康促进研究”队列研究的参与者。我们收集了人口统计学变量信息，在基线时测量了步速、简易精神状态检查表得分和血清IGF-1。在随访期间，通过长期护理保险认证监测新发残疾情况。
在平均29.2个月的随访期内，212名参与者出现了残疾。对数秩检验表明，血清IGF-1水平较低与新发残疾有关（p = 0.004）。Cox风险回归显示，与最高四分位数（Q4）相比，IGF-1处于较低四分位数与残疾相关，即使在调整了包括步速和简易精神状态检查表得分在内的协变量后也是如此（Q1：风险比 = 1.72，95%置信区间：1.06 - 2.81；Q2：风险比 = 1.64，95%置信区间：0.99 - 2.71；Q3：风险比 = 1.31，95%置信区间：0.76 - 2.25）。在按性别分层的分析中，IGF-1与女性残疾之间也存在显著关系，但男性中不存在。
血清IGF-1水平较低与老年人残疾独立相关。
