Fabricatore A N, Wadden T A, Moore R H, Butryn M L, Gravallese E A, Erondu N E, Heymsfield S B, Nguyen A M
Center for Weight and Eating Disorders, Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Obes Rev. 2009 May;10(3):333-41. doi: 10.1111/j.1467-789X.2009.00567.x. Epub 2009 Mar 6.
Clinical trials of obesity treatments have been limited by substantial dropout. Participant-level variables do not reliably predict attrition, and study-level variables have not yet been examined. We searched MEDLINE and identified 24 large randomized controlled trials of weight loss medications. These trials were comprised of 23 placebo and 32 drug groups. Two authors independently extracted the following for each treatment group: (i) treatment received; (ii) design characteristics (inclusion of a lead-in period, selection of participants with weight-related comorbidities, study location and number of study visits); (iii) sample characteristics (sample size, % female, and mean baseline age and body mass index); and (iv) attrition (total, adverse event [AE]-related and non-AE-related) at 1 year. The primary outcome was total attrition, which was significantly related to treatment (i.e. 34.9%, 28.6%, 28.3% and 35.1% in placebo, orlistat, sibutramine and rimonabant groups, respectively, P < 0.0001). In adjusted multivariable models, total attrition was significantly lower in groups that completed a pre-randomization lead-in period than in those that did not (29.1% vs. 39.9%, P < 0.01). Gender also was significantly related to total attrition; groups with more women had higher dropout (P < 0.01). The pattern was similar for predicting non-AE-related attrition. Findings suggest ways to design studies that maximize retention.
肥胖治疗的临床试验因大量受试者退出而受到限制。受试者层面的变量无法可靠地预测损耗情况，而研究层面的变量尚未得到研究。我们检索了MEDLINE并确定了24项减肥药物的大型随机对照试验。这些试验包括23个安慰剂组和32个药物组。两位作者独立为每个治疗组提取了以下信息：（i）接受的治疗；（ii）设计特征（是否包含导入期、选择有体重相关合并症的参与者、研究地点和研究访视次数）；（iii）样本特征（样本量、女性百分比、平均基线年龄和体重指数）；以及（iv）1年时的损耗情况（总计、与不良事件[AE]相关和与非AE相关）。主要结局是总损耗，其与治疗显著相关（即安慰剂组、奥利司他组、西布曲明组和利莫那班组的总损耗分别为34.9%、28.6%、28.3%和35.1%，P<0.0001）。在调整后的多变量模型中，完成随机化前导入期的组的总损耗显著低于未完成导入期的组（29.1%对39.9%，P<0.01）。性别也与总损耗显著相关；女性较多的组退出率较高（P<0.01）。预测非AE相关损耗的模式类似。研究结果提示了设计能最大限度提高保留率的研究的方法。
