Li Ying, Meng Lu, Miao QianQian, Sato Yasuto
Department of Social Medicine, School of Public Health, Zhejiang University, Hangzhou, China.
Geriatr Gerontol Int. 2014 Jul;14(3):647-53. doi: 10.1111/ggi.12152. Epub 2013 Sep 11.
Serum C-peptide is an active peptide that has important physiological functions and characteristics in the elderly. The present study aimed to investigate the association between physical activity and serum C-peptide level independent of insulin level among the elderly.
The study included 1700 elderly participants aged ≥ 65 years. Stratified analysis of covariance was used to compare serum C-peptide levels in participants with different physical activity levels. Two separate multiple linear regression models were created to estimate the association between physical activity and serum C-peptide level.
The results of analysis of covariance stratified by sex, body mass index and serum insulin level showed that those who engaged in vigorous physical activity had lower serum C-peptide levels than those who engaged in light or no physical activity. Separate multiple linear regression analysis showed that in those with low serum C-peptide levels (≤ 0.621 nmol/L), physical activity was significantly positively associated with the serum C-peptide level. In contrast, physical activity was negatively associated with the serum C-peptide level among those with serum C-peptide level >0.621 nmol/L.
The serum C-peptide level showed a significant two-way association with physical activity. The present findings suggest that physical activity modification is important for improving serum C-peptide levels among the elderly.
血清C肽是一种活性肽，在老年人中具有重要的生理功能和特性。本研究旨在探讨老年人中体力活动与血清C肽水平之间的关联，且不考虑胰岛素水平的影响。
该研究纳入了1700名年龄≥65岁的老年人。采用分层协方差分析比较不同体力活动水平参与者的血清C肽水平。建立两个独立的多元线性回归模型来估计体力活动与血清C肽水平之间的关联。
按性别、体重指数和血清胰岛素水平分层的协方差分析结果显示，进行剧烈体力活动的参与者血清C肽水平低于进行轻度或无体力活动的参与者。单独的多元线性回归分析表明，血清C肽水平较低（≤0.621 nmol/L）的人群中，体力活动与血清C肽水平呈显著正相关。相反，血清C肽水平>0.621 nmol/L的人群中，体力活动与血清C肽水平呈负相关。
血清C肽水平与体力活动呈显著的双向关联。目前的研究结果表明，改变体力活动对提高老年人血清C肽水平很重要。
