Data_Sheet_1_High Bodyweight Variability Increases Depression Risk in Patients With Type 2 Diabetes Mellitus: A Nationwide Cohort Study in Korea.docx

Objectives: Although obesity is associated with increased risk for depression in patients with type 2 diabetes mellitus (DM), the relationship between body weight variability (BWV) and depression remains poorly studied. This study was to investigate the incidence of depression in patients with type 2 DM according to their BWV.
Methods: Intraindividual variation in body weight were measured in the nationwide, population-based retrospective cohort of 540,293 patients with type 2 DM from the Korean national health insurance system between 2009 and 2010. The diagnoses of new-onset depression occurring until the end of 2017 were ascertained. Risk of new-onset depression was examined using multivariate-adjusted Cox proportional hazards regression analysis by BWV quartile.
Results: 93,149 (17.2%) patients developed new-onset depression for the follow up. BWV was significantly associated with an increased risk of depression after adjusting for confounding factors. The highest BWV quartile group had a hazard ratio (HR) of 1.17 (95% CI 1.15–1.19) compared to the lowest BWV quartile group as a reference. Obese patients in the highest BWV quartile group showed 12% increased risk of depression (HR 1.12, 95% CI 1.09–1.15) while non-obese patients in the highest BWV quartile group showed 20% increased risk of depression (HR: 1.20, 95% CI: 1.17–1.23) compared to their respective lowest BWV quartile groups.
Conclusion: A higher BWV was significantly associated with an increased risk of depression in patients with type 2 DM. Thus, BWV may serve as an indicator for early detection of depression in type 2 DM patients.

研究目的：尽管肥胖与2型糖尿病（type 2 diabetes mellitus, DM）患者的抑郁风险升高相关，但体重变异性（body weight variability, BWV）与抑郁之间的关联仍鲜有研究。本研究旨在依据2型糖尿病患者的体重变异性，探究其抑郁的发病情况。
研究方法：本研究依托韩国国民健康保险系统，纳入2009至2010年间的540293名2型糖尿病患者，构建全国性人群回顾性队列，对受试者的个体内体重变异情况进行测量。追踪至2017年末，确认所有新发抑郁的诊断病例。采用按体重变异性四分位数分组的多变量校正Cox比例风险回归模型，分析新发抑郁的发病风险。
研究结果：随访期间共有93149名（17.2%）患者发生新发抑郁。在校正混杂因素后，体重变异性与抑郁风险升高显著相关。以最低体重变异性四分位组为参照，最高四分位组的风险比（hazard ratio, HR）为1.17（95%置信区间：1.15~1.19）。与各自组内最低体重变异性四分位组相比，最高四分位组的肥胖患者抑郁风险升高12%（HR=1.12，95%置信区间：1.09~1.15），而非肥胖患者抑郁风险升高20%（HR=1.20，95%置信区间：1.17~1.23）。
研究结论：2型糖尿病患者的体重变异性升高与抑郁风险升高显著相关。因此，体重变异性可作为2型糖尿病患者抑郁早期筛查的潜在指标。