Long-term outcomes of macrovascular diseases and metabolic indicators of bariatric surgery for severe obesity type 2 diabetes patients with a meta-analysis

There is currently no detailed evidence for the long-term effects of bariatric surgery on severely obese with type 2 diabetes, such as the risk of myocardial infarction and stroke. In order to provide evidence on the risks of macrovascular diseases and metabolic indicators of bariatric surgery follow-up for more than five years, we searched in the Cochrane library, Pubmed, and EMBASE databases from the earliest studies to January 31, 2019. Randomized clinical trials or cohort studies compared bariatric surgery and conventional medical therapy for long-term incidence of macrovascular events and metabolic outcomes in severely obese patients with T2DM. Fixed-effects and random-effects meta-analyses were performed to pool the relative risks (RRs), hazard ratios (HRs) and weighted mean difference (WMD). Publication bias and heterogeneity were examined. Four RCTs and six cohort studies were finally involved in this review. Patients in the bariatric surgery group as compared to the conventional treatment group had lower incidence of macrovascular complications (RR = 0.43, 95%CI = 0.27~0.70), cardiovascular events (CVEs) (HR = 0.52, 95%CI = 0.39~0.71), and myocardial infarction (MI) (RR = 0.40, 95%CI = 0.26~0.61). At the same time, the results demonstrate that bariatric surgery is associated with better weight and better glycemic control over the long-term than non-surgical therapies, and reveal that different surgical methods have different effects on various metabolic indicators. Bariatric surgery significantly decreases macrovascular complications over the long term and is associated with greater weight loss and better intermediate glucose outcomes among T2DM patients with severe obesity as compared to patients receiving only conservative medical measures.目前尚无针对重度肥胖合并2型糖尿病（type 2 diabetes, T2DM）患者接受减重代谢手术（bariatric surgery）的长期影响的详实证据，其中包括心肌梗死（myocardial infarction, MI）与卒中的发病风险。为获取减重代谢手术术后随访超5年的大血管疾病风险及代谢指标相关证据，本研究检索了Cochrane图书馆、PubMed及EMBASE数据库，检索时限自建库至2019年1月31日。纳入对比减重代谢手术与常规药物治疗对重度肥胖合并T2DM患者大血管事件长期发生率及代谢结局影响的随机对照试验（randomized clinical trial, RCT）与队列研究。采用固定效应模型与随机效应模型进行Meta分析，合并相对风险（relative risk, RR）、风险比（hazard ratio, HR）及加权均数差（weighted mean difference, WMD），并评估发表偏倚与异质性。本综述最终纳入4项RCT与6项队列研究。与常规治疗组相比，减重代谢手术组患者的大血管并发症（RR=0.43，95%CI：0.27~0.70）、心血管事件（cardiovascular events, CVEs）（HR=0.52，95%CI：0.39~0.71）及心肌梗死（MI）（RR=0.40，95%CI：0.26~0.61）发生率更低。同时，研究结果显示，相较于非手术治疗方案，减重代谢手术在长期随访中可更有效地控制体重与血糖水平，且不同术式对各类代谢指标的影响存在差异。相较于仅接受保守药物治疗的患者，重度肥胖合并T2DM患者接受减重代谢手术后，长期大血管并发症发生率显著降低，同时伴随更显著的体重下降与更优的中期血糖结局。