Therapeutics
Review: Bariatric surgery increases weight loss and diabetes remission more than nonsurgical treatment
Gloy VL, Briel M, Bhatt DL, et al. Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomised controlled trials. BMJ. 2013;347:f5934.
Clinical impact ratings: F ★★★★★★✩ C ★★★★★✩✩ e ★★★★★✩✩ Question
In obese patients, what is the relative efficacy of bariatric surgery and nonsurgical weight-loss treatment?
Source of funding: No external funding. For correspondence: V. L. Gloy, University Hospital Basel, Basel, Switzerland. E-mail [email protected]. ■
Review scope
Commentary
Included studies compared laparoscopic or open bariatric surgery techniques with nonsurgical treatment for obesity in patients with a body mass index (BMI) ≥ 30 and reported on the outcomes of interest, including body weight, waist circumference, cholesterol levels, blood pressure, diabetes remission, and metabolic syndrome remission.
While both bariatric surgery and nonsurgical interventions can lead to sustained weight loss, controlled comparisons between the approaches are rare. The review of 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. Review methods Bariatric surgery is an intensive intervention, yet no study has MEDLINE, EMBASE/Excerpta Medica, Cochrane Library (all included a truly intensive nonsurgical comparison group. Appetiteto Jun 2013), and trial registries were searched for randomized suppressing drugs (ASD) were not used as part of nonsurgical controlled trials (RCTs) with ≥ 6 months of follow-up. 11 RCTs treatment in any of the included RCTs. Among the newer ASDs, (n = 796, 14% to 100% men) met the selection criteria. Mean both phentermine/topiramate ER and lorcaserin have shown BMI ranged from 30 to 52. 5 RCTs included only patients with efficacy for up to 2 years. Evaluating a nonsurgical approach type 2 diabetes, 3 included only patients who had a previous serious without strategic inclusion of ASDs is like evaluating management attempt at weight loss, and 1 included only patients with obstrucof hypertension without using antihypertensive drugs. tive sleep apnea. Follow-up was 2 years in 6 trials, 1 year in 4 trials, and 40 weeks in 1 trial. Randomization sequence generation was Data for long-term outcomes (≥ 5 y) for both surgical and nonclearly adequate in 10 trials, and allocation was clearly concealed surgical treatments are limited. Even after surgery, slow regain of in 6 RCTs. weight is common, and some patients regain all lost weight. Risks and costs are clearly greater with surgery than with nonsurgical Main results treatment, although neither is risk- or cost-free. Similar to the Meta-analyses showed that bariatric surgery increased weight loss, long-term Look AHEAD trial of nonsurgical weight loss (1), the remission from diabetes, remission from the metabolic syndrome, meta-analysis by Gloy and colleagues did not show reductions in and high-density lipoprotein cholesterol levels compared with cardiovascular events or mortality after bariatric surgery. nonsurgical treatments (Table). Bariatric surgery reduced waist The approach to seriously obese patients at our specialized circumference and hemoglobin A1c levels more than nonsurgical center remains first to rule out medical triggers of weight gain treatments, but groups did not differ for low-density lipoprotein and to address such situational triggers as changes in diet, physicholesterol levels or systolic or diastolic blood pressure (Table). cal activity, and life-altering events. The next step is team-based Conclusion (dietitian, behavioral psychologist, exercise expert, and physician) In obese patients, bariatric surgery increases weight loss and treatment combined with low-calorie diets, exercise, and behavior remission from diabetes and the metabolic syndrome more than modification. ASDs and bariatric surgery are potential options nonsurgical weight-loss treatments. thereafter. As with many conditions we encounter, surgery is an option but not necessarily Bariatric surgery vs nonsurgical weight-loss treatments in patients with body mass index the first approach. Pitting surgery against ≥ 30* medical management creates a false dichotomy: Appropriate surgical interOutcomes Number of Weighted At 40 wks to 2 y vention requires ongoing medical mantrials (n) event rates agement and support; responsible medical Bariatric Nonsurgical RBI (95% CI) NNT (CI) management considers bariatric surgery. surgery treatment Further studies should evaluate how Type 2 diabetes remission 4 (352) 57% 2.3% 2110% (220 to 15 330) 2 (1 to 18) these complementary treatments are best used, integrated, and paid for; financial Metabolic syndrome remission 5 (288) 62% 26% 140% (60 to 260) 3 (2 to 7) coverage of obesity treatments is perhaps Mean difference (CI) the greatest limitation to their best use. Change in body weight (kg)
10 (658)
−25.9 (−30.9 to −21.0)†
Change in waist circumference (cm)
6 (458)
−15.6 (−18.1 to −13.0)†
Change in HDL cholesterol level (mmol/L)
8 (670)
0.2 (0.1 to 0.3)‡
Change in LDL cholesterol level (mmol/L)
5 (487)
−0.6 (−1.2 to 0.0)†
Change in systolic blood pressure (mm Hg)
7 (567)
−8.8 (−26.2 to 8.5)†
Change in diastolic blood pressure (mm Hg)
6 (471)
−0.4 (−2.9 to 2.1)†
Change in HbA1c level (%)
5 (470)
−1.5 (−1.9 to −1.1)†
*HbA1c = hemoglobin A1c; HDL = high-density lipoprotein; LDL = low-density lipoprotein; other abbreviations defined in Glossary. RBI, NNT, and CI calculated from control event rates and risk ratios in article using a random-effects model.
Lawrence J. Cheskin, MD, FACP, FTOS Scott Kahan, MD, MPH, FTOS Johns Hopkins Bloomberg School of Public Health Baltimore, Maryland, USA Reference 1. Look AHEAD Research Group, Wing RR, Bolin P, et al. Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes. N Engl J Med. 2013;369:145-54.
†Negative difference favors bariatric surgery. ‡Positive difference favors bariatric surgery.
21 January 2014 | ACP Journal Club | Volume 160 • Number 2
© 2014 American College of Physicians
Downloaded From: https://annals.org/pdfaccess.ashx?url=/data/journals/aim/929674/ by a Weill Medical College User on 07/17/2017
JC7
Review: Bariatric surgery increases weight loss and diabetes remission more than nonsurgical treatment
Gloy VL, Briel M, Bhatt DL, et al. Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomised controlled trials. BMJ. 2013;347:f5934.
Clinical impact ratings: F ★★★★★★✩ C ★★★★★✩✩ e ★★★★★✩✩ Question
In obese patients, what is the relative efficacy of bariatric surgery and nonsurgical weight-loss treatment?
Source of funding: No external funding. For correspondence: V. L. Gloy, University Hospital Basel, Basel, Switzerland. E-mail [email protected]. ■
Review scope
Commentary
Included studies compared laparoscopic or open bariatric surgery techniques with nonsurgical treatment for obesity in patients with a body mass index (BMI) ≥ 30 and reported on the outcomes of interest, including body weight, waist circumference, cholesterol levels, blood pressure, diabetes remission, and metabolic syndrome remission.
While both bariatric surgery and nonsurgical interventions can lead to sustained weight loss, controlled comparisons between the approaches are rare. The review of 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. Review methods Bariatric surgery is an intensive intervention, yet no study has MEDLINE, EMBASE/Excerpta Medica, Cochrane Library (all included a truly intensive nonsurgical comparison group. Appetiteto Jun 2013), and trial registries were searched for randomized suppressing drugs (ASD) were not used as part of nonsurgical controlled trials (RCTs) with ≥ 6 months of follow-up. 11 RCTs treatment in any of the included RCTs. Among the newer ASDs, (n = 796, 14% to 100% men) met the selection criteria. Mean both phentermine/topiramate ER and lorcaserin have shown BMI ranged from 30 to 52. 5 RCTs included only patients with efficacy for up to 2 years. Evaluating a nonsurgical approach type 2 diabetes, 3 included only patients who had a previous serious without strategic inclusion of ASDs is like evaluating management attempt at weight loss, and 1 included only patients with obstrucof hypertension without using antihypertensive drugs. tive sleep apnea. Follow-up was 2 years in 6 trials, 1 year in 4 trials, and 40 weeks in 1 trial. Randomization sequence generation was Data for long-term outcomes (≥ 5 y) for both surgical and nonclearly adequate in 10 trials, and allocation was clearly concealed surgical treatments are limited. Even after surgery, slow regain of in 6 RCTs. weight is common, and some patients regain all lost weight. Risks and costs are clearly greater with surgery than with nonsurgical Main results treatment, although neither is risk- or cost-free. Similar to the Meta-analyses showed that bariatric surgery increased weight loss, long-term Look AHEAD trial of nonsurgical weight loss (1), the remission from diabetes, remission from the metabolic syndrome, meta-analysis by Gloy and colleagues did not show reductions in and high-density lipoprotein cholesterol levels compared with cardiovascular events or mortality after bariatric surgery. nonsurgical treatments (Table). Bariatric surgery reduced waist The approach to seriously obese patients at our specialized circumference and hemoglobin A1c levels more than nonsurgical center remains first to rule out medical triggers of weight gain treatments, but groups did not differ for low-density lipoprotein and to address such situational triggers as changes in diet, physicholesterol levels or systolic or diastolic blood pressure (Table). cal activity, and life-altering events. The next step is team-based Conclusion (dietitian, behavioral psychologist, exercise expert, and physician) In obese patients, bariatric surgery increases weight loss and treatment combined with low-calorie diets, exercise, and behavior remission from diabetes and the metabolic syndrome more than modification. ASDs and bariatric surgery are potential options nonsurgical weight-loss treatments. thereafter. As with many conditions we encounter, surgery is an option but not necessarily Bariatric surgery vs nonsurgical weight-loss treatments in patients with body mass index the first approach. Pitting surgery against ≥ 30* medical management creates a false dichotomy: Appropriate surgical interOutcomes Number of Weighted At 40 wks to 2 y vention requires ongoing medical mantrials (n) event rates agement and support; responsible medical Bariatric Nonsurgical RBI (95% CI) NNT (CI) management considers bariatric surgery. surgery treatment Further studies should evaluate how Type 2 diabetes remission 4 (352) 57% 2.3% 2110% (220 to 15 330) 2 (1 to 18) these complementary treatments are best used, integrated, and paid for; financial Metabolic syndrome remission 5 (288) 62% 26% 140% (60 to 260) 3 (2 to 7) coverage of obesity treatments is perhaps Mean difference (CI) the greatest limitation to their best use. Change in body weight (kg)
10 (658)
−25.9 (−30.9 to −21.0)†
Change in waist circumference (cm)
6 (458)
−15.6 (−18.1 to −13.0)†
Change in HDL cholesterol level (mmol/L)
8 (670)
0.2 (0.1 to 0.3)‡
Change in LDL cholesterol level (mmol/L)
5 (487)
−0.6 (−1.2 to 0.0)†
Change in systolic blood pressure (mm Hg)
7 (567)
−8.8 (−26.2 to 8.5)†
Change in diastolic blood pressure (mm Hg)
6 (471)
−0.4 (−2.9 to 2.1)†
Change in HbA1c level (%)
5 (470)
−1.5 (−1.9 to −1.1)†
*HbA1c = hemoglobin A1c; HDL = high-density lipoprotein; LDL = low-density lipoprotein; other abbreviations defined in Glossary. RBI, NNT, and CI calculated from control event rates and risk ratios in article using a random-effects model.
Lawrence J. Cheskin, MD, FACP, FTOS Scott Kahan, MD, MPH, FTOS Johns Hopkins Bloomberg School of Public Health Baltimore, Maryland, USA Reference 1. Look AHEAD Research Group, Wing RR, Bolin P, et al. Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes. N Engl J Med. 2013;369:145-54.
†Negative difference favors bariatric surgery. ‡Positive difference favors bariatric surgery.
21 January 2014 | ACP Journal Club | Volume 160 • Number 2
© 2014 American College of Physicians
Downloaded From: https://annals.org/pdfaccess.ashx?url=/data/journals/aim/929674/ by a Weill Medical College User on 07/17/2017
JC7
