Department of Biostatistics, University of Michigan, Ann Arbor, Michigan, USA.
Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA.
Obesity (Silver Spring). 2021 Jan;29(1):213-219. doi: 10.1002/oby.23031. Epub 2020 Nov 16.
Obesity treatment is plagued by attrition. Estimates of attrition bias are needed. Thus, in this study, percent change from baseline BMI at 1, 2, and 3 years following enrollment in a 2-year weight management program using a very low-energy diet was calculated. Program data were supplemented with information from medical records.
Attrition was classified as occurring early (<6 months), late (6-21 months), at program completion (22-28 months), and after program completion (>28 months). Stepwise multivariable regression examined attrition and other covariates.
A total of 881 subjects had ≥3 years of follow-up. BMI decreased by a mean (SD) of 11.8 (9.2), 8.6 (9.3), and 5.2 (10.0) kg/m at 1, 2, and 3 years after enrollment, respectively. At year 1, every 10-kg/m increase in baseline BMI was associated with a 2% (95% CI: 1%-3%) decrease in BMI. Individuals with early attrition decreased their mean BMI by 13% (11%-15%) less than program completers and by 9% (7%-11%) at 2 years. At 3 years, there was no significant difference in BMI between individuals with early attrition and program completers. However, BMI decreased 5% (3%- 8%) more in individuals who extended participation compared with program completers.
Reported outcomes of weight management programs must account for program attrition.
肥胖治疗存在大量脱落现象。因此，本研究计算了参加为期 2 年的极低能量饮食体重管理项目的患者在入组后第 1、2 和 3 年时体重指数（BMI）相对于基线的百分比变化，以此评估脱落偏倚的估计值。项目数据由医疗记录中的信息补充。
脱落分为早期（<6 个月）、晚期（6-21 个月）、项目完成时（22-28 个月）和项目完成后（>28 个月）。逐步多元回归分析考察了脱落及其他协变量的影响。
共有 881 名患者的随访时间≥3 年。BMI 分别平均下降了 11.8（9.2）kg/m²、8.6（9.3）kg/m²和 5.2（10.0）kg/m²，分别在入组后第 1、2 和 3 年。第 1 年，基线 BMI 每增加 10-kg/m²，BMI 下降 2%（95%CI：1%-3%）。与项目完成者相比，早期脱落者的平均 BMI 下降幅度小 13%（11%-15%），在第 2 年时下降幅度小 9%（7%-11%）。第 3 年，早期脱落者和项目完成者的 BMI 无显著差异。然而，与项目完成者相比，延长参与时间的个体 BMI 下降了 5%（3%-8%）。
报告的体重管理项目结果必须考虑项目脱落。
