Dietary protein effects in elderly women: musculoskeletal, renal, cardiovascular and body composition endpoints

从伤残和医疗费用的角度来看，老年人骨折和跌倒是我们社会的主要健康问题。发展非药物干预措施以维持健康到老年，对我们老龄化人口的未来健康至关重要。流行病学研究表明，在老年人中，相对较高的蛋白质摄入量与骨矿物质的增加和骨质疏松性骨折的发生率降低有关。蛋白质摄入量过低会导致肌肉质量下降。到目前为止，还没有足够持续时间的随机试验来检验增加饮食蛋白质摄入量对老年人骨骼和肌肉健康的影响。本研究的目的是通过监测肾功能和心血管疾病的危险因素，研究蛋白质补充对老年妇女预防骨质疏松症和肌肉萎缩的有效性，以及这种干预的安全性。220名女性将被招募到这项研究中，并被分配到蛋白质组或安慰剂组。蛋白质组的女性每天将摄入250毫升的高蛋白饮料(含30克蛋白质)，而安慰剂组的女性将接受含有等量能量、钙但不含额外蛋白质的安慰剂饮料。在为期两年的研究期间，将监测骨骼结构、肌肉质量、身体成分、肾功能和心血管疾病的风险因素。这项随机对照研究的结果将阐明蛋白质对老年人骨量和结构、肌肉质量和身体组成的作用。同时，还将评估这种干预对肾脏和心血管终点的安全性。预计这项研究的结果如果是肯定的，将转化为立即适用的干预策略，在项目和个人层面上都是相关的。

Fractures and falls of the elderly are major health problems in our community in terms of disability and cost. It is critical to the future health of our aging population to develop non-pharmaceutical interventions to maintain health into old age. Epidemiologic studies have shown that relatively high protein intake is associated with increased bone mineral mass and reduced incidence of osteoporotic fracture in elderly people. Low protein intakes can lead to loss of muscle mass. To date there have been no randomised trials of sufficient duration to examine the effects of increased dietary protein intake on bone and muscle health of the elderly. The aim of this study is to examine the effectiveness of protein supplementation for the prevention of osteoporosis and muscle wasting in elderly women, and the safety of such an intervention through monitoring renal function and risk factors for cardiovascular disease. Two hundred and twenty women will be recruited to this study and be assigned to protein group or placebo group. Women in the protein group will received 250 ml high protein drink (containing 30 g protein) per day and women in the placebo group will receive placebo drink containing the same amount of energy, calcium but no additional protein. Bone structure, muscle mass, body composition, renal function and risk factors for cardiovascular disease will be monitored during the 2 year study period. The results of this randomised, controlled study will clarify the role of protein on bone mass and structure, muscle mass and body composition in the elderly. At the same time, the safety of such intervention on renal and cardiovascular endpoints will also be evaluated. It is envisaged that the results of this study if positive will translate into both immediately applicable intervention strategies that are relevant at a program and an individual level.