Question

Comparison of theeffectiveness of four bariatric surgery procedures inobese patients with type 2 diabetes: a retrospectivestudy.

Answer 1

Bariatric surgery has proven to be a treatment of choice for morbid obesity [1, 2]. It is recommended for patients with body mass index (BMI) above 40 kg/m2 or higher than 35 kg/m2 when associated with comorbidities which include the different components of metabolic syndrome and type 2 diabetes [3, 4]. Weight loss obtained after bariatric surgery is associated with a highly significant reduction in cardiovascular risk factors [5–7]. More recently, improvement or remission of diabetes has been observed following bariatric surgery in obese patients with type 2 diabetes and mortality rate linked to diabetes was consequently significantly reduced [1, 2, 8–12]. Weight loss induced by bariatric surgery is a major factor of diabetes improvement [11, 13]. However, in several studies, the resolution of diabetes has often been observed before a significant weight loss has been obtained [14–17]. The early postsurgical improvement of diabetes suggested a major physiopathological role for changes in gut hormone secretion [18]. As a matter of fact, a decrease in plasma levels of ghrelin, an orexigenic peptide, has been described following gastric bypass for morbid obesity [19–22]. The involvement of other intestinal peptides like GLP-1 (hindgut hypothesis) [23–26] and neuropeptide YY [22, 27–30] or a decreased secretion of anti-incretin hormones (foregut hypothesis) [31, 32] has been proposed to explain the rapid remission of diabetes after bariatric surgery. Otherwise, Roux-en-Y bypass (RYGB) that excludes the duodenum from the nutriments’ route and profoundly modifies the gut microbial metabolic cross-talk [33] has been shown to improve insulin resistance more rapidly than sleeve gastrectomy [15].

These observations raised the question of the choice of chirurgical procedure for treating diabetes. Most studies have compared two by two procedures. Using this approach, RYGB and sleeve gastrectomy (SG) seem to be more efficient for treating diabetes than gastric banding (GB). However, these studies failed to provide clear conclusions owing to the great heterogeneity of the results. For instance, depending on the mode of surgery used (restrictive, malabsorptive, or combined) and study design, the diabetes remission rate varied from 45 to 97% of patients [5, 9, 12, 34–39]. In our center, four surgical procedures have been used for the last 15 years to treat obesity, GB, SG, calibrated gastrectomy type Mason (CGMa), and RYGB. The aim of the present retrospective study was to evaluate the efficacy of these four procedures to induce diabetes remission and lower cardiovascular risk factors. Moreover, the influence of surgery on weight evolution in the diabetic population was compared with that observed in a nondiabetic population matched for sex, age, BMI, and surgical procedure.