The effects of bariatric procedures versus medical therapy for obese patients with type 2 diabetes: meta-analysis of randomized controlled trials.

Objective: To assess the effects of bariatric surgery versus medical therapy for type 2 diabetes mellitus.

Methods: The Cochrane library, PubMed, Embase, Chinese biomedical literature database, and Wanfang database up to February 2012 were searched. The literature searches strategies contained terms ("diabetes*", "surg*", and "medic*" were used), combined with the medical subject headings. Randomized controlled trails (RCTs) of frequently used bariatric surgery for obese patients with type 2 diabetes were included. Study selection, data extraction, quality assessment, and data analyses were performed according to the Cochrane standards.

Results: Three randomized controlled trials (RCTs) involving 170 patients in the bariatric surgery groups and 100 patients in the medical therapy group were selected. Compared with medical therapy, bariatric surgery for type 2 diabetes can significantly decrease the levels of HbA1c, FBG, weight, triglycerides, and the dose of hypoglycemic, antihypertensive, and lipid-lowering medicine, while increasing the rate of diabetes remission (RR = 9.74, 95%CI, (1.36, 69.66)) and the levels of high-density lipoprotein. However, there are no statistical differences in serious adverse events between the surgical and medical groups (RR = 1.23, 95%CI, (0.80, 1.87)).

Conclusions: Surgical procedures were more likely to help patients achieve benefits than medical therapy alone. Further intensive RCTs of high-quality, multiple centers and long-term followup should be carried out to provide more reliable evidence.