PUBLISHED SCIENTIFIC EVIDENCE ON OBESITY SURGERY
Thousands of research papers have now been published regarding obesity surgery.
There have been a few landmark studies published highlighting the benefits of weight loss surgery and comparing different weight loss procedures.
SWEDISH OBESE SUBJECTS TRIAL
The Swedish Obese Subjects Trial (SOS) was one of the largest trials comparing surgical and nonsurgical treatments for obesity.
In summary it is the largest trial comparing surgical vs medical treatment for severe obesity, with 4047 patients studied in a prospective non randomized controlled trial with and average follow-up >10 yrs.
The found the following results;
- Weight decrease 23% at 2yrs, 16% at 10yrs in the surgery group
- Weight increase 0.1% at 2yrs, 1.6% at 10yrs in nonsurgical group
- Energy intake lower in surgery group
- Physical activity higher in surgery group
- Surgery group reduced incidence Diabetes, Hypertension, hypercholesterolaemia
- Surgery group reduced medications and cost of medications
- Surgery group better scores on quality of life (QOL) psychiatric assessment
TRIAL COMPARING GASTRIC BANDING AND CONVENTIONAL THERAPY FOR TYPE 2 DIABETES
The randomized controlled trial published by John Dixon and Paul O'Brien, et al. in the JAMA 2008;299:316, is another landmark paper comparing Laparoscopic
In summary, this trial compared the effect of Gastric Banding with Conventional Treatments for 60 patients with BMI 30-40 and Type 2 Diabetes (DM) with 2year follow up. The trial found the following results;
- Remission DM 73% in surgery group, 13% in conventional treatment group
- 62.5% EWL in surgery group, 4.3% EWL in conventional treatment group
- LAGB significantly more effective for mild - moderate obesity (BMI 30-35) at 2yr
POSITION STATEMENT ON BARIATRIC SURGERY FOR TYPE 2 DIABETES FORM INTERNATIONAL DIABETES FEDERATION
With the overwhelming benefit of weight loss surgery on diabetes now well proven, the published a
In summary, the IDF statement concludes that;
- Bariatric surgery is an appropriate treatment for people with Type 2 DM and severe obesity BMI>35.
- Surgery should be prioritized for severely obese patients with Type 2 DM.
- Under some circumstances people with BMI 30-35 should be considered for surgery (HbA1c>7.5% despite fully optimized conventional therapy, esp if weight increasing, or if other weight related co-morbidities not achieving targets on conventional therapies ie BP, cholesterol, sleep apnea).
- BMI action point may be lower (27.5-32.5) for some ethnicities.
- Surgery be integrated as treatment option for Type 2 DM along with lifestyle modification and pharmacological therapy.
SYSTEMATIC REVIEW AND META-ANALYSIS ON BARIATRIC SURGERY
In 2004, a meta-analysis titled was published in the JAMA 2004;292:1724, which summarized 136 studies on weight loss surgery, examining > 22000 patients.
In summary this meta-analysis examined the effect of weight loss surgery on the comorbidities associated with obesity and found that weight loss surgery was associated significant cure or improvement in diabetes, hypertension, hyperlipidemia, sleep apnea, reflux, and urinary incontinence;
- Diabetes -77% resolved, 86% improved
- Hypertension - 62% resolved, 79% improved
- Hyperlipidemia - >70% improved
- Obstructive Sleep Apnea - 86% resolved, 84% improved
- Gastroesophageal reflux improved
- Urinary stress incontinence decreased by 47%
The same study also found that weight loss surgery
- Reduces overall and cause-specific mortality
- Reduces medication costs
- Reduces sick days
- Improves Quality of Life
- Benefits strongest in BMI>40
- 61% mean overall EWL (excess weight loss)
- Greatest weight loss with Laparoscopic Gastric Bypass
- Overall mortality < 1%
- Morbidity approx. 20%