EFFECT OF WEIGHT LOSS ON BONE HEALTH IN POSTMENOPAUSAL BREAST CANCER SURVIVORS

描述（由申请人提供）：众所周知，体重减轻对骨骼健康有不良影响，特别是对绝经后妇女。一些研究表明，体育活动，特别是负重活动，可以抵消骨质流失。考虑到与几种治疗方案相关的骨质流失，乳腺癌幸存者可能特别容易出现骨质健康不良。关于减肥和运动对癌症幸存者骨骼健康的影响的研究有限。几项研究表明，运动可能会抵消乳腺癌幸存者的骨质流失，但这些研究都没有包括减肥的成分。考虑到能量限制是大多数成功减肥方案的关键组成部分，了解它对绝经后乳腺癌幸存者骨骼健康的作用是一个重要的安全考虑因素，绝经后乳腺癌幸存者骨质流失的风险增加。ENERGY试验（运动和营养促进恢复和健康）是一项先锋减肥试验，在美国四个地点进行n=800名年龄在21岁及以上的IC-IIIA期乳腺癌超重和肥胖女性（RO1CA14879）。减肥主要是通过限制能量来实现的，同时强调有氧运动来补充减肥并促进减肥的维持。因此，它为研究绝经后乳腺癌幸存者体重变化和体力活动与骨质流失之间的关系提供了一个理想的环境。我们的主要假设是体重减轻和体育活动将与超重和肥胖绝经后乳腺癌幸存者的骨质流失和重塑相关。我们将通过收集在圣路易斯地点（华盛顿大学医学院）参加ENERGY试验的绝经后妇女（预计占n=200的75%）的补充数据来检验这一点。本研究的目的是在最初的减肥阶段（从随机分组到12个月）描述骨丢失和重塑的特征。我们的建议是创新的，因为它将是第一个前瞻性评估减肥期间有意减肥和体育活动对超重和肥胖绝经后乳腺癌幸存者骨骼健康的影响的研究，无论是独立的还是共同的。鉴于肥胖对乳腺癌幸存者的发病率和死亡率的不利影响，这一点非常重要，因为人们非常关注乳腺癌幸存者体重管理的必要性。骨密度的结果可以直接指导临床实践和对乳腺癌后妇女的建议。具体来说，我们的目的是在一项随机对照减肥试验中测量超重和肥胖绝经后乳腺癌幸存者的体重变化与体育活动和骨质流失之间的相关性，其次，表征体重变化和体育活动之间的相互作用，因为它与骨质流失有关。

DESCRIPTION (provided by applicant): Weight loss is known to have adverse consequences for bone health, particularly in postmenopausal women. Some research has indicated that physical activity, particularly weight-bearing activity, may offset bone loss. Breast cancer survivors may be at particular risk for adverse bone health given the bone loss associated with several treatment regimens. There is limited research on the effects of weight loss and exercise on bone health in cancer survivors. Several studies have suggested that exercise may offset bone loss in breast cancer survivors, but these studies have not included a weight loss component. Given that energy restriction is a key component to most successful weight loss regimens, understanding the role it has on bone health in postmenopausal breast cancer survivors, who are at increased risk for bone loss, is an important safety consideration. The ENERGY trial (Exercise and Nutrition to Enhance Recovery and Good health for You) is a vanguard weight loss trial of n=800 overweight and obese women age 21 and older with stage IC-IIIA breast cancer across four sites in the US (RO1CA14879). Weight loss is achieved primarily through energy restriction with concurrent emphasis on aerobic exercise to complement weight loss and promote maintenance of weight loss. Thus, it provides an ideal setting to examine the associations between weight change and physical activity with bone loss in postmenopausal breast cancer survivors. Our primary hypothesis is that weight loss and physical activity will be correlated with bone loss and remodeling among overweight and obese postmenopausal breast cancer survivors. We will examine this through the collection of supplementary data in the postmenopausal women (expected to be 75% of the n=200) enrolled in the ENERGY trial at the St. Louis site (at Washington University School of Medicine). The goal of this study is to characterize bone loss and remodeling during the primary weight loss phase (from randomization to 12 months). Our proposal is innovative in that it will be the first study to prospectively assess the effects of intentional weight loss and physical activity during weight loss, independently and together, on bone health in overweight and obese postmenopausal breast cancer survivors. This is significant as there is great attention to the need for weight management in breast cancer survivors given the adverse effects of obesity on morbidity and mortality in this population. Results on bone density can directly inform clinical practice and recommendations for women after breast cancer. Specifically, our aims are to measure the correlation between weight change and physical activity and bone loss among overweight and obese postmenopausal breast cancer survivors enrolled in a randomized controlled weight loss trial and, secondarily, to characterize the interaction between weight change and physical activity as it relates to bone loss.