Su-Hsin Chang of the Washington University School of Medicine in St. Louis and colleagues reviewed available medical literature and analyzed 164 studies -- 37 randomized clinical trials and 127 observational studies from 2003 to 2012 that included 161,756 patients with an average age almost 45 years and body mass index of nearly 46. A BMI of 19 to 25 is considered normal weight and a BMI of 35 or higher is considered obese.
Chang said bariatric surgery helps patients lose weight and get rid of obesity-related diseases such as diabetes and hypertension although the risk of complications, reoperation and death remain.
The sleeve Gastrectomy is an operation in which the left side of the stomach is surgically removed. For the Lap-Band Adjustable Gastric Band, surgeons use laparoscopic techniques to place the band around the upper part of the stomach, forming a small gastric pouch to limit food intake and slow the food passing from the stomach into the intestines. Gastric bypass surgery makes the stomach smaller and allows food to bypass part of the small intestine.
Among the findings, published in JAMA Surgery were:
-- Within 30 days of surgery, the death rate was 0.08 percent, and 30 days after surgery, the rate was 0.31 percent -- lower than thought.
-- BMI loss five years after surgery ranged from 12 points to 17 points.
-- Complication rates ranged from 10 percent to 17 percent.
-- The reoperation rate was about 7 percent.
-- Obesity-related diseases, including diabetes, hypertension and sleep apnea, improved after surgery.
-- Adjustable gastric banding had lower death and complication rates but re-operation rates were higher and weight loss was less than gastric bypass.
-- Sleeve gastrectomy appeared to be more effective for weight loss than adjustable gastric banding and comparable with gastric bypass.
"In conclusion, our study suggests that bariatric surgery has substantial and sustained effects on weight and significantly ameliorates obesity-attributable comorbidities in the majority of bariatric patients," the study researchers wrote in the study.