Keyhole Surgery or Intense Dieting for Obesity?

Summarized by Robert W. Griffith, MD
September 12, 2006

Summary

Laparoscopic gastric-band surgery has clear advantages over intensive non-surgical treatment of mild to moderately obese people.

Introduction

Surgery for obesity is a rapidly developing treatment that has changed quite a bit in the last few years. Most recently, gastric banding through laparoscopic openings ('keyhole surgery') has become popular. But is it really better than a strict diet regime? A relatively small Australian study comparing the two approaches has been reported in the Annals of Internal Medicine, which we summarize here.

What was done

Patients with mild to moderate obesity (a body mass index, or BMI, ranging from 30 to 35 kg/mm²) were allocated at random to have surgery or a non-surgery treatment regimen for 24 months. They had to be between 20 and 50, and to have tried to reduce weight over the previous 5 years. Over 340 patients were assessed for eligibility, resulting in 80 who were suitable for allocation to one group or the other.

The surgery involved placing an adjustable band around the stomach, so that the patient would feel full after eating a small amount; the band was placed through small incisions in the abdominal wall, done under general anesthesia. The band could be adjusted by inflating the amount of saline the inner layer contained, according to the individual patient needs.

The non-surgical program consisted of an intensive 6-month phase, using a very-low-calorie diet (500-550 calorie/day for the first 3 months), with subsequent introduction of Xenical^® (orlistat). In the second phase, there were further courses of very-low-calorie diet and orlistat, as tolerated, together with continued emphasis on behavioral changes to improve diet and exercise program habits.

Weight change and the presence of the metabolic syndrome were measured in all patients.¹ This involved blood pressure, waist measurements, blood lipid levels, and fasting blood sugar determinations. In addition, a quality-of-life scale was administered at intervals, as well as enquiries about side effects. Attention was focused on the results at 24 months after enrollment.

What was found

Of the 80 patients enrolled in the study, 15 in each group had the metabolic syndrome, by definition.¹ That is to say, they had physical changes suggestive of decreased insulin sensitivity, which is commonly associated with an increased risk of cardiovascular disorders. Their average age was 41; roughly ¾ of them were women.

Both surgical and non-surgical groups had identical weight loss for the first 6 months, amounting to an average of 14% of their initial body weight. The surgical group continued to lose weight for the balance of the 24 months, while the non-surgical group showed progressive weight gain.

After 24 months, the gastric banding patients had lost an average of 22% of their initial body weight, while the non-surgical patients had lost 5.5%. Only one of the original patients in the gastric banding group still had the metabolic syndrome, compared with 8 in the non-surgical group. And the quality-of-life measurements showed significant improvements in 3 of 8 domains in the non-surgical group, compared with all 8 domains in the surgery group.

Four of the surgery patients (10%) had a slight shift of the band in relation to the stomach wall, necessitating correction using laparoscopy; in each of these cases, symptoms were those of gastroesophageal reflux. Other adverse events in the surgical group were trivial.

In the non-surgery group, one patient couldn't tolerate the very-low-calorie diet and 8 couldn't tolerate orlistat; 3 others chose not to use orlistat. Four of them had acute cholecystitis requiring a laparoscopic cholecystectomy.

What these results mean

Clearly, laparoscopic surgery with adjustable gastric banding was superior to the non-surgical program used in this 2-year study. While this result might have been expected for people with severe obesity, they were remarkable in a group of mild to moderate obese patients. One criticism is that the investigators did not adequately describe the regime imposed on the non-surgical patients after the 6-month intensive period, i.e. during the time when they regained so much weight. If this had been stricter, the outcomes at 24 months might have been more similar.

Unfortunately, the study was not large enough to say, with statistical certainty, that there were no differences with regard to safety. However, gastric banding has been shown to be safe in people with morbid obesity and in super-obese patients, and it's certainly less risky than gastric bypass.

Surgical intervention for people with a BMI in the 30 to 35 range is not generally recommended, at present; such people should preferably be treated by diet, medication, and lifestyle changes. The findings here, however, may encourage patients to press their doctors for a surgical solution to their problem. Further studies should be completed first, though, to establish a more definitive risk:benefit ratio for this particular population.

Source

• Treatment of mild to moderate obesity with laparoscopic adjustable gastric banding or an intensive medical program. PE. O'Brien, JB. Dixon, C. Laurie,  et al. , Ann Intern Med, 2006, vol. 144, pp. 625--633

Footnotes
1. The metabolic syndrome requires 3 of the following risk factors to be present: (a) Waist size over 40 inches (102 cm) in men, or 35 inches (88 cm) in women. (b) Serum triglyceride level over 150 mg/dL (1.7 mmol/L). (c) Serum HDL ('good') cholesterol below 40 mg/dL (1.0 mmol/L) in men, or 50 mg/dL (1.29 mmol/L) in women. (d) Blood pressure over 130/85 mm Hg (either number), or being on blood pressure medication. (e) Fasting blood sugar over 110 mg/dL (6.1 mmol/L). Take the self-test, at the link below.

Related Links
BMI Calculator
Orlistat (Xenical®)
Lap-Band System

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