Review: Bariatric surgery increases weight loss and diabetes remission more than nonsurgical treatment

A meta-analysis of 11 randomized, controlled trials (including more than 700 patients, some with and some without diabetes, all with a body mass index of 30 kg/m² or higher) found that bariatric surgery improved weight loss, remission from diabetes, remission from metabolic syndrome, high-density lipoprotein cholesterol levels, waist circumference and HbA1c more than nonsurgical treatment. The groups did not differ in low-density lipoprotein cholesterol levels or blood pressure.

The study was published by BMJ on Oct. 22, 2013. The following commentary by Lawrence J. Cheskin, MD, FACP, and Scott Kahan, MD, MPH, was published in the ACP Journal Club section of the Jan. 21 Annals of Internal Medicine.

While both bariatric surgery and nonsurgical interventions can lead to sustained weight loss, controlled comparisons between the approaches are rare. The review of randomized, controlled trials (RCTs) by Gloy and colleagues provides the highest-quality evidence to date for the relative effectiveness of bariatric surgery. Still, concerns about the relative efficacy, sustainability, and risks of these 2 forms of treatment are warranted.

Bariatric surgery is an intensive intervention, yet no study has included a truly intensive nonsurgical comparison group. Appetite-suppressing drugs (ASD) were not used as part of nonsurgical treatment in any of the included RCTs. Among the newer ASDs, both phentermine/topiramate ER and lorcaserin have shown efficacy for up to 2 years. Evaluating a nonsurgical approach without strategic inclusion of ASDs is like evaluating management of hypertension without using antihypertensive drugs.

Data for long-term outcomes (≥ 5 years) for both surgical and nonsurgical treatments are limited. Even after surgery, slow regain of weight is common, and some patients regain all lost weight. Risks and costs are clearly greater with surgery than with nonsurgical treatment, although neither is risk- or cost-free. Similar to the long-term Look AHEAD trial of nonsurgical weight loss, the meta-analysis by Gloy and colleagues did not show reductions in cardiovascular events or mortality after bariatric surgery.

The approach to seriously obese patients at our specialized center remains first to rule out medical triggers of weight gain and to address such situational triggers as changes in diet, physical activity, and life-altering events. The next step is team-based (dietitian, behavioral psychologist, exercise expert, and physician) treatment combined with low-calorie diets, exercise, and behavior modification. ASDs and bariatric surgery are potential options thereafter.

As with many conditions we encounter, surgery is an option but not necessarily the first approach. Pitting surgery against medical management creates a false dichotomy: Appropriate surgical intervention requires ongoing medical management and support; responsible medical management considers bariatric surgery. Further studies should evaluate how these complementary treatments are best used, integrated, and paid for; financial coverage of obesity treatments is perhaps the greatest limitation to their best use.