COMMENT ON CUMMINGS AND COHEN Bariatric/Metabolic Surgery to Treat Type 2 Diabetes in Patients With a BMI ,35 kg/m 2 . Diabetes Care 2016;39:924–933 Diabetes Care 2017;40:e71–e72 | https://doi.org/10.2337/dc16-1482 In a recent article, Cummings and Cohen (1) compared glycemic outcomes after bariatric surgery in patients with BMI $35 or ,35 kg/m 2 , concluding that there was no clear difference in outcomes between these BMI thresholds. To strengthen their argument, they dis- cussed possible weight-independent effects of bariatric surgery on glycemic outcomes. Their article correctly recognized the 35 kg/m 2 threshold used as an indica- tion for bariatric surgery, based on a 1991 National Institutes of Health Con- sensus Statement (2), as arbitrary and probably not suitable for Asian patients, and it discussed the fact that initial BMI does not predict outcome in larger cohorts. However, many points dis- cussed in the article should be analyzed with caution, given the limited number of less obese patients with long-term follow-up after metabolic surgery and the few existing comparisons of BMI ex- tremes. Additionally, many studies have demonstrated that diabetes remission is associated with the amount of weight loss and that, when the amount of weight loss is the same, restrictive tech- niques have similar remission rates to “metabolic” procedures such as Roux-en-Y gastric bypass/vertical sleeve gastrectomy (RYGB/VSG) (3–5). To compare outcomes in patients with BMI above and below 35 kg/m 2 , the authors used a forest plot (Fig. 3 in ref. 1) including different studies in pa- tients with mean BMI above or below 35 kg/m 2 . However, we believe it would be more appropriate to compare indi- viduals rather than studies. Only one randomized controlled trial (RCT) has directly compared patients with a base- line BMI above or below 35 kg/m 2 (6). At 36 months after randomization, sub- jects in the lower BMI range took ap- proximately twice as many diabetes medications as subjects with a BMI above 35 kg/m 2 . Although this was one of the few studies not considering med- ication discontinuation as a criterion for diabetes remission, it was nonetheless included in the meta-analysis with stud- ies using different criteria. The plot in Fig. 3 (1) included a single long-term study in patients with mean BMI #35 kg/m 2 who underwent RYGB/ VSG. Although the mean baseline BMI was not predictive of remission, there was a clear relationship between weight loss and glycemic control (7). After 3 years, there was a clear increase in rates of diabetes relapse and clinically significant adverse events; moreover, the overall results in this study were in- ferior to those in studies of patients with higher mean BMI (3,8). Among the other four studies of patients with mean BMI #35 kg/m 2 , two had a follow-up of only 1 year and one assessed laparoscopic adjustable gastric banding (LAGB) (as the authors claim weight-independent effects of surgery related to incretin changes, they should have analyzed RYGB/VSG and LAGB separately). The fourth study, by Courcoulas et al., was erroneously allocated, as it included patients with a mean BMI of 35.6 kg/m 2 (1). A critical review of the RCTs listed in both plot columns found only about 70 individuals with class I obesity and type 2 diabetes who underwent RYGB and had at least 2 years of follow-up, a number obviously too negligible to prompt a change in public health policies (1). Lack of studies with long-term follow-up is a major concern in less obese patients, considering that these patients lose less weight and their small weight regain could cause glycemic deterioration. The current data should prompt caution given the increased rates of diabetes relapse seen in all stud- ies of bariatric surgery with extended follow-up (6–8). We would like to emphasize that, in our opinion, the indication for bariatric surgery should not rely solely on BMI or on a dichotomous threshold value. On the basis of a myriad of currently available RCTs, we should amplify access to surgery for higher-BMI patients with shorter diabetes duration who are more likely to achieve glycemic improvement 1 Obesity Unit, Department of Endocrinology, Hospital das Cl´ınicas, University of São Paulo, São Paulo, Brazil 2 Brazilian Association for the Study of Obesity and Metabolic Syndrome, São Paulo, Brazil 3 Department of Obesity, Brazilian Society of Endocrinology and Metabolism, Rio de Janeiro, Brazil Corresponding author: Bruno Halpern, brunohalpern@hotmail.com. © 2017 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license. Bruno Halpern, 1,2 Cintia Cercato, 1,2,3 and Marcio Correa Mancini 1,2,3 Diabetes Care Volume 40, June 2017 e71 e-LETTERS – COMMENTS AND RESPONSES