NEW YORK (Reuters Health) – Sleeve gastrectomy leads to significant improvement or resolution of type 2 diabetes in morbidly obese patients, and is much more effective than intensive conventional medical therapy, confirms a comparative study of patients treated at the Centre for the Surgical-Medical Treatment of Morbid Obesity, Policlinico “Umberto I,” University of Rome “Sapienza,” Italy.

The surgery also leads to improvement in several obesity-related comorbidities including obstructive sleep apnea syndrome, hypertension and dyslipidemia, Dr. Frida Leonetti and colleagues reported in Archives of Surgery April 16.

In an invited critique, Dr. Jon C. Gould, of the Medical College of Wisconsin, Milwaukee, writes: “This is a nice contribution, but, by now, this kind of outcome should not come as a surprise to any bariatric surgeon or regular reader of the Archives of Surgery.”

“These findings,” he adds, “demonstrate to the bariatric community that there is a great opportunity to partner with primary care physicians and to educate the public on the significant benefits and safety of bariatric surgery. National guidelines for bariatric surgery need to be developed for people with type 2 diabetes and a body mass index of 35 or more (calculated as weight in kilograms divided by height in meters squared).”

Dr. Leonetti and colleagues say the efficacy of laparoscopic sleeve gastrectomy on remission or improvement of type 2 diabetes has been shown in a number of studies, but, to their knowledge, it’s never been compared with intensive medical therapy.

They studied 60 morbidly obese patients with type 2 diabetes; half underwent sleeve gastrectomy and the other half underwent conventional medical therapy for their diabetes. They assessed the patients every three months for 18 months.

The two groups were matched for BMI, sex, hemoglobin A1C level, C-peptide level, type of therapy and duration of diabetes. In the surgery group, 25 patients had hypertension, 28 had dyslipidemia and 15 were on continuous positive airway pressure therapy for severe OSAS. In the medical therapy group, 25 patients had hypertension, 26 had dyslipidemia and seven were being treated with CPAP for severe OSAS.

The remission of type 2 diabetes was defined as a fasting glucose level of less than 100 mg/dL, hemoglobin A1C level less than 6.0% without the use of hypoglycemic drugs, and a glucose level less than 140 mg/dL using the 120-minute oral glucose tolerance test for glycemia.

According to the investigators, type 2 diabetes resolved in 80% of patients who had the surgery (24 of 30), including all 20 patients (100%) who had type 2 diabetes for fewer than 10 years, and four of the 10 patients (40%) who had it for more than 10 years.

In contrast, all the patients treated with intensive conventional medical therapy remained diabetic and continued or increased their level of hypoglycemic therapy.

With regard to other obesity-related comorbidities, in the surgery group, the prevalence of OSAS dropped from 50% to 10% and patients in this group significantly reduced their use of medication for hypertension and dyslipidemia, “with consequent economic benefits.” Sleeve gastrectomy improved the lipid profile (increasing HDL-cholesterol levels and decreasing triglycerides).

In contrast, use of antihypertensive and hypolipemic medications increased in patients in the medical therapy group and the prevalence of OSAS held steady.

Dr. Leonetti and colleagues say, “Midterm and long-term results are needed to confirm the positive effect (remission and/or improvement) of laparoscopic sleeve gastrectomy on diabetes and, overall, on the chronic complications of the disease. Most importantly, the longer-term results will allow us to compare the costs and benefits of bariatric surgery vs conventional medical treatments.”

In his critique, Dr. Gould says, “An obese diabetic patient should have access to bariatric surgery in appropriate clinical circumstances. This access should be uniform, consistent, and not subject to potential bias, differences in opinion, or a lack of understanding regarding contemporary bariatric surgery outcomes.”

Arch Surg 2012. Published online April 16, 2012.