Aetion, Inc., New York, New York, USA.
Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA.
Diabetes Obes Metab. 2021 Jul;23(7):1453-1462. doi: 10.1111/dom.14338. Epub 2021 Feb 19.
To reproduce and correct studies on bariatric surgery and the reduction in major adverse cardiovascular events (MACE) among patients with obesity and type 2 diabetes (T2D).
We used electronic healthcare records (EHR) from in and outpatient facilities around the United States to identify a cohort of patients with T2D, aged 18 to 80 years and with a body mass index (BMI) of 30 kg/m or higher undergoing bariatric surgery. We compared against hip/knee arthroplasty to establish an active comparison group that reduced bias from differential information and confounding. The main outcome was six-point MACE. Pre-exposure characteristics were adjusted in propensity score (PS) models with 1:2 matching plus high-dimensional PS matching.
After a range of exclusions, the final cohort included 344 bariatric surgery patients (65% female; mean age 58 years) and 551 PS-matched patients undergoing arthroplasty (65% female; 59 years). Median follow-up was 2.5 years in both groups. Bariatric surgery patients showed a sustained 20% weight reduction and an HbA1c reduction by 1% point. We found no benefits of bariatric surgery for six-point MACE (HR = 0.99; 95% CI 0.76-1.30). We observed known increases in risks for vitamin B deficiency anaemia (HR = 3.06; 1.10-8.49) and cholelithiasis (HR = 1.72; 0.94-3.13).
This real-world evidence study found reductions in HbA1c and BMI following bariatric surgery similar to trials, and no meaningful cardiovascular benefit compatible with the underpowered trials but in contrast to earlier EHR studies. We showed how information bias typical in EHR analyses and confounding may cause substantial bias.
复制和纠正肥胖合并 2 型糖尿病（T2D）患者行减重手术与主要不良心血管事件（MACE）减少相关的研究。
我们使用美国各地的门诊和住院电子病历（EHR），识别出一组年龄在 18 至 80 岁之间、BMI 为 30kg/m²或更高的 T2D 患者，接受减重手术。我们与髋/膝关节置换术进行比较，以建立一个主动对照组，从而减少因信息差异和混杂因素导致的偏倚。主要结局为六点 MACE。采用倾向评分（PS）模型进行调整，模型包括 1:2 匹配和高维 PS 匹配。
经过一系列排除后，最终队列纳入 344 名减重手术患者（65%为女性；平均年龄 58 岁）和 551 名 PS 匹配的关节置换患者（65%为女性；59 岁）。两组的中位随访时间均为 2.5 年。减重手术患者体重持续减轻 20%，HbA1c 降低 1%。我们发现减重手术对六点 MACE 没有益处（HR=0.99；95%CI 0.76-1.30）。我们观察到维生素 B 缺乏性贫血（HR=3.06；1.10-8.49）和胆石症（HR=1.72；0.94-3.13）风险增加。
这项真实世界证据研究发现，减重手术后 HbA1c 和 BMI 降低与试验相似，且与试验相比，没有意义的心血管获益，但与早期 EHR 研究相反。我们展示了 EHR 分析中常见的信息偏倚和混杂因素如何导致显著的偏倚。
