Division of Endocrinology and Metabolism, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
J Gerontol A Biol Sci Med Sci. 2012 Jan;67(1):74-81. doi: 10.1093/gerona/glr022. Epub 2011 Feb 24.
Diabetes is associated with decreased muscle mass. The effect of higher levels of glucose and insulin on muscle mass has not been studied in individuals without diabetes. We sought to determine the relationship of insulin and glucose measurements from the oral glucose tolerance test (OGTT) with muscle mass in persons without diabetes.
We analyzed data from 587 participants in the Baltimore Longitudinal Study of Aging (mean age 67.3 years, range 26-95 years) without diabetes who underwent a 2-hour OGTT, including glucose and insulin measurements taken every 20 minutes and assessment of midthigh muscle cross-sectional area by computed tomography, taken as a proxy measure of muscle mass. Linear regression models and Bayesian model averaging were used to explore the independent cross-sectional association of various OGTT-derived measures and midthigh muscle cross-sectional area, independent of confounders.
Individually, fasting glucose, fasting insulin, OGTT glucose (40, 60, 80, 100, and 120 minutes), OGTT insulin (20, 60, 80, 100, and 120 minutes), homeostasis model assessment of insulin resistance, integrated glucose area, and integrated insulin area were inversely associated, and the Matsuda index was positively associated, with the midthigh muscle cross-sectional area (standardized to body weight) after adjustment for age, sex, race, height, physical activity, and peroneal motor nerve conduction velocity (all ps <.05). When considered together, the Matsuda index and fasting glucose were the strongest predictors of lower midthigh muscle cross-sectional area after covariate adjustment.
Higher fasting and OGTT values of both glucose and insulin are associated with lower muscle mass. Longitudinal studies are needed to verify whether individuals free of diabetes that have higher glucose and insulin during an OGTT are at risk for accelerated muscle mass decline with aging.
糖尿病与肌肉量减少有关。在没有糖尿病的个体中，尚未研究较高水平的葡萄糖和胰岛素对肌肉量的影响。我们旨在确定口服葡萄糖耐量试验（OGTT）中的胰岛素和葡萄糖测量值与无糖尿病个体肌肉量之间的关系。
我们分析了来自巴尔的摩纵向衰老研究（平均年龄 67.3 岁，范围 26-95 岁）的 587 名无糖尿病参与者的数据，他们进行了 2 小时 OGTT，包括每 20 分钟测量一次葡萄糖和胰岛素，以及通过计算机断层扫描评估大腿中段肌肉横截面积，作为肌肉量的替代测量值。线性回归模型和贝叶斯模型平均用于探索各种 OGTT 衍生测量值与大腿中段肌肉横截面积的独立横断面关联，独立于混杂因素。
单独来看，空腹血糖、空腹胰岛素、OGTT 葡萄糖（40、60、80、100 和 120 分钟）、OGTT 胰岛素（20、60、80、100 和 120 分钟）、稳态模型评估的胰岛素抵抗、综合葡萄糖面积和综合胰岛素面积与大腿中段肌肉横截面积（按体重标准化）呈负相关，Matsuda 指数与大腿中段肌肉横截面积呈正相关（校正年龄、性别、种族、身高、体力活动和腓总运动神经传导速度后所有 p 值均<.05）。在考虑到其他因素后，Matsuda 指数和空腹血糖是调整后的大腿中段肌肉横截面积的最强预测因子。
较高的空腹和 OGTT 葡萄糖和胰岛素值与较低的肌肉量相关。需要进行纵向研究以验证在 OGTT 中无糖尿病的个体葡萄糖和胰岛素水平较高是否有加速肌肉量随年龄减少的风险。
