WEIGHT LOSS--BONE & SKELETAL MUSCLE HOMEOSTASIS IN NIDDM

患有2型糖尿病的严重肥胖女性（BMI为35 - 40）骨骼质量增加。他们的无脂肪量也增加了，可能包括增加的骨骼肌。这些妇女不断尝试减肥，以改善她们的糖尿病控制。过去一般都是通过医学手段来尝试减肥，但严重肥胖的女性越来越频繁地接受减肥手术。随着体重的减少，无论是通过药物还是手术，脂肪量都会减少。此外，有证据表明骨骼和骨骼肌中的钙也会流失。我们计划调查两组2型糖尿病女性在减肥过程中骨矿物质和骨骼肌的损失，一组通过低热量饮食减肥，另一组通过胃旁路手术减肥。要测试的假设是，随着体重的减少：1)两组人的骨骼肌都会减少；2)在适当补充钙和维生素D的情况下，骨钙不会流失；3)骨转换生化指标升高；4)手术组胃肠道钙吸收受损；5)生活质量的提高与体重减轻成正比。我们将研究年龄在25 - 45岁，BMI在35 - 40之间的绝经前糖尿病女性。在基线、6个月、1年和2年时，采用核心a和b生化指标测量身体成分和生活质量。两组将比较这些参数的变化，以及血糖控制（糖化血红蛋白）、血压和血脂的改善。Core C将用于数据存储、数据分析和结果的统计评估。由于我国严重肥胖的糖尿病女性尝试减肥的发生率很高，并且随着减肥手术干预措施的增加，是否对骨骼和肌肉产生不良影响对于评估此类尝试的风险-收益比非常重要。在2型糖尿病患者中，没有足够的关于胃旁路反应的骨质流失和肌肉质量的数据，因此该建议是及时的，具有公共卫生重要性。

Severely obese women (BMI 35 to 40) with type 2 diabetes mellitus have an increased skeletal mass. They also have an increased fat-free mass, presumably including increased skeletal muscle. These women are continually attempting to lose weight in order to improve their diabetes control. Attempts at weight loss have generally been carried out medically in the past, but severely obese women are undergoing bariatric surgery more and more frequently. With weight loss, by whatever means, medical or surgical, fat mass is lost. In addition, there is some evidence that calcium from bone and skeletal muscle mass is also lost. We plan to investigate the loss of bone mineral and skeletal muscle during weight loss in two groups of women with type 2 diabetes, one group losing weight on a hypocaloric diet and another group losing weight with gastric by-pass surgery. The hypotheses to be tested are that, with weight loss: 1) skeletal muscle will be lost in both groups; 2) bone calcium will not be lost if subjects are appropriately supplemented with calcium and vitamin D; 3) biochemical markers of bone turnover will be elevated; 4) gastrointestinal calcium absorption will be impaired in the surgical group; 5) quality of life will improve in proportion to amount of weight loss. We will study pre-menopausal diabetic women with a BMI range of 35 to 40, aged 25 to 45 years. Measures of body composition using Core A&B biochemical markers, and quality of life will be taken at baseline, 6 months, one year, and two years. The two groups will be compared for changes in these parameters and also for improvement in glucose control (HgbA1c), blood pressure, and blood lipids. Core C will be used for data storage, data analysis, and statistical evaluation of results. With the great incidence of weight loss attempts in this country by severely obese diabetic women, and with the increasing bariatric surgery interventions, whether adverse effects on bone and muscle occur is important in estimating the risk-benefit ratio of such attempts. There are no adequate data on bone loss and one on muscle mass in response to gastric by-pass in type 2 diabetic patients, so that the proposal is timely and has public health importance.