Bariatric surgery in patients with morbid obesity and type 2 diabetes.

T here is an epidemic of obesity throughout the developed and much of the developing world (1– 3). Obesity, typically measured as BMI 30 kg/m, has three subclasses: obesity 1 (30–34.9 kg/m); obesity 2 (35–39.9 kg/m); and extreme obesity ( 40 kg/ m). Extreme or morbid obesity is rapidly increasing in the U.S. and may have the potential of decreasing life expectancy. From 1986 to 2000, the prevalence of BMI 30 kg/m doubled, whereas that of BMI 40 kg/m quadrupled, and even extreme obesity of BMI 50 kg/m increased fivefold (2). Of particular concern is the alarming increasing prevalence of obesity among children (1), suggesting that the epidemic will worsen before it improves. Epidemiologic studies have demonstrated that increasing BMI is a causative factor in many life-threatening comorbidities, including type 2 diabetes, cardiovascular disease, and cancer. BMI has been established as an independent risk factor for premature mortality (4). Obesity is a major independent risk factor for the development of type 2 diabetes and is associated with the rapid increase in the prevalence of type 2 diabetes (3). In the U.S., the majority diagnosed with type 2 diabetes are overweight, with 50% obese (i.e., BMI 30 kg/m) and 9% morbidly obese (BMI 40 kg/m) (5). This twin epidemic of obesity and diabetes carries severe consequence for premature mortality (6). Lifestyle intervention programs with diet therapy, behavior modification, exercise programs, and pharmacotherapy are widely used in various combinations. Unfortunately, with extremely rare exceptions (7), clinically significant weight loss is generally very modest and transient, particularly in patients with severe obesity. In a recently published study (8), 80 adults with mild to moderate obesity (BMI 30–35 kg/m) were randomized to nonsurgical intervention (very-lowcalorie diet, orlistat, and lifestyle change) or to surgical intervention (gastric banding); surgical treatment was significantly more effective than nonsurgical therapy in reducing weight, resolving the metabolic syndrome, and improving quality of life during a 24-month treatment program (8). At 2 years, the surgical group had greater weight loss, with a mean of 21.6% of initial weight loss and 87.2% of excess weight loss, whereas the nonsurgical group had a loss of 5.5% of initial weight and 21.8% of excess weight (P 0.001). When morbidly obese patients with a BMI 40 kg/m were willing to complete an intensive behavioral program, a remarkable weight loss of 35% of the initial body weight was observed after 40 weeks,. For completers, average weight loss for women was 30.8 kg (23.9%) and for men was 42.6 kg (26.7%) over 39 weeks. However, long-term maintenance of weight loss is difficult for most individuals, as also noted in this particular study (7). Bariatric surgery includes several surgical procedures that can be performed in obese patients. Per the 1991 National Institutes of Health Consensus Conference Guidelines, patients are considered as surgical candidates only if their BMI is 40 kg/m or if their BMI is 35 kg/m and they suffer from other life-threatening comorbidities, such as type 2 diabetes, hypertension, and cardiovascular disease. Presently, the three most common surgical procedures for obesity are the Roux-en-Y gastric bypass, the vertical banded gastroplasty, and the adjustable gastric band with sleeve gastrectomy and duodenal switch, which is less commonly performed. In the Swedish Obesity Study (SOS), the mean changes in weight and risk factors were more favorable among the subjects treated by gastric bypass than among those treated by banding or vertical banded gastroplasty (9). The maintained weight change over 10 years was 25% in the gastric bypass subgroup. In the year 2002–2003, worldwide, 146,301 bariatric surgery operations were performed by 2,839 bariatric surgeons, and 103,000 of these operations were performed in U.S./ Canada by 850 surgeons (10). The outcomes after surgically induced weight loss published in the last years are impressive (9,11,12). In a metaanalysis of 22,094 patients (mean age 47 years, mean BMI 46.9, 72.6% women), the mean percentage of excess weight loss was 61.2% for all patients (12). Excessive weight loss was higher for patients who underwent gastric bypass (61.6%) or gastroplasty (68.2%) compared with those who received gastric banding (47.5%). Remarkably, diabetes was completely resolved in 76.8% of patients and resolved or improved in 86.0%. Hyperlipidemia improved in 70% of patients, and hypertension was resolved in 61.7% and reso lved and improved in 78.5%. Obstructive sleep apnea was resolved in 85.7% of patients and was resolved or improved in 83.6% of patients. The long-term outcome data of a controlled surgical intervention study of obesity (Swedish Obesity Study) were recently reported by Lars Sjöström at the International Federation of Surgery for Obesity congress in Sydney as well as at the European Association for the Study of Diabetes (EASD) congress in Copenhagen (13). In the Swedish Obesity Study, a surgical group of 2,010 patients (matched by age, sex, BMI, and comorbidities) was compared with a nonsurgical control group consisting of 2,037 patients, and ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●