Khoury Jane, Jenkins Todd M, Ehrlich Shelley, Boles Richard, Michalsky Marc P, Inge Thomas H, Szczesniak Rhonda D
Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center.
Department of Pediatrics, University of Cincinnati.
Ann Biom Biostat. 2020;5(1). Epub 2020 Jul 13.
Obesity is identified as a major global health problem. Along with measuring body mass index (BMI), the most common metric for defining weight status, health related quality of life (HRQol) has been accepted as a routine method to evaluate how body weight may be impacted by psychosocial factors. The objective of the current study is to characterize the joint association of change in longitudinal BMI and HRQol following metabolic and bariatric surgery and to examine the correlation between these two outcomes measured concurrently over time. We identified the optimal modeling strategy by comparing four models, all of which involved the covariance structures appropriate for correlated outcomes, BMI and HRQol in a repeated measures analysis. The bivariate random effects models performed better than the univariate random effects models. Moreover, bivariate models with composite covariate structures had better model fit compared to the bivariate random slope models. The bivariate models with composite covariate structures reflected that changes in HRQol (and BMI) were most significant during the first 6 months, a clinically useful window to monitor changes in post-operative HRQol and BMI, and if there might need to be additional interventions or at least, closer monitoring.
肥胖被视为一个主要的全球健康问题。除了测量体重指数（BMI）这一界定体重状况最常用的指标外，健康相关生活质量（HRQol）已被公认为评估体重如何受心理社会因素影响的常规方法。本研究的目的是描述代谢和减重手术后纵向BMI变化与HRQol的联合关联，并检验这两个随时间同时测量的结果之间的相关性。我们通过比较四个模型确定了最佳建模策略，所有这些模型在重复测量分析中都涉及适合相关结果（BMI和HRQol）的协方差结构。双变量随机效应模型比单变量随机效应模型表现更好。此外，与双变量随机斜率模型相比，具有复合协变量结构的双变量模型具有更好的模型拟合度。具有复合协变量结构的双变量模型表明，HRQol（和BMI）的变化在最初6个月最为显著，这是一个监测术后HRQol和BMI变化的临床有用窗口，以及是否可能需要额外干预或至少进行更密切监测的窗口。
