Yuki Atsumu, Otsuka Rei, Kozakai Rumi, Kitamura Itsuko, Okura Tomohiro, Ando Fujiko, Shimokata Hiroshi
Department for Development of Preventive Medicine, National Center for Geriatrics and Gerontology, Japan.
Sci Rep. 2013;3:1818. doi: 10.1038/srep01818.
We assessed longitudinal relationships between baseline testosterone and muscle mass changes in Japanese men. Data were collected from community-dwelling 957 adult men who participated in a longitudinal study of ageing biennially from 1997-2010. Appendicular muscle mass (AMM) was measured with dual-energy X-ray absorptiometry at baseline and follow-up examinations. The cut-off point of sarcopenia was defined as a skeletal muscle index (AMM/height(2)) < 6.87 kg/m(2). Total testosterone (TT) and free testosterone (FT) were measured with a radioimmunoassay. The calculated FT (cFT) was determined with a formula using albumin, TT, and sex hormone-binding globulin levels. We analyzed 4,187 or 2,010 cumulative data points using generalized estimating equations. Low TT was not associated with sarcopenia. Low cFT (odds ratio = 2.14, 95% confidence interval: 1.06-4.33) and FT (odds ratio = 1.83, 95% confidence interval: 1.04-3.22) were associated with sarcopenia. Low FT may be a predictor of risk for muscle loss in Japanese men.
我们评估了日本男性基线睾酮水平与肌肉量变化之间的纵向关系。数据收集自957名居住在社区的成年男性，他们从1997年至2010年每两年参与一次衰老纵向研究。在基线和随访检查时，用双能X线吸收法测量四肢肌肉量（AMM）。肌肉减少症的切点定义为骨骼肌指数（AMM/身高²）<6.87 kg/m²。用放射免疫分析法测量总睾酮（TT）和游离睾酮（FT）。计算得出的游离睾酮（cFT）通过使用白蛋白、TT和性激素结合球蛋白水平的公式来确定。我们使用广义估计方程分析了4187或2010个累积数据点。低TT与肌肉减少症无关。低cFT（比值比=2.14，95%置信区间：1.06 - 4.33）和FT（比值比=1.83，95%置信区间：1.04 - 3.22）与肌肉减少症相关。低FT可能是日本男性肌肉量减少风险的一个预测指标。
