Laparoscopic sleeve gastrectomy (LSG) has proved highly effective in alleviating type 2 diabetes (T2DM) and its complications compared with traditional medical treatment, according to a newly published study.
The new study comes on the heels of two randomized trials published late last month in the New England Journal of Medicine, which found that various forms of bariatric surgery -- including Roux-en-Y gastric bypass as well as sleeve gastrectomy -- led to significantly greater improvements in diabetes control relative to medical therapy.
Numerous uncontrolled studies had previously found similar benefits from bariatric surgery.
According to a group led by Nicola Basso, MD, of the University of Rome Sapienza, the prospective cohort study involving 30 morbidly obese diabetic patients undergoing laparoscopic sleeve gastrectomy, compared with 30 similar patients receiving usual drug-based care, measures of diabetic control were improved far more with the surgical procedure.
Patients receiving medical therapy showed modest improvements from baseline in major diabetic outcomes after 18 months -- fasting plasma glucose levels fell by more than 30 mg/dL and hemoglobin A1c values declined by one percentage point -- but diabetes was nearly eradicated in the surgical patients, Basso and colleagues reported.
Jon C. Gould, MD, of the Medical College of Wisconsin in Milwaukee, commented in an accompanying critique that the results were no longer surprising, and that the time had now come to develop formal guidelines for bariatric surgery as a diabetes treatment.
"An obese diabetic patient should have access to bariatric surgery in appropriate clinical circumstances," Gould wrote. "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."
In the new Italian study, Basso and colleagues examined outcomes in 30 patients with body mass index (BMI) values of at least 35 (mean 41.3, maximum 53.4) and type 2 diabetes who chose to undergo sleeve gastrectomy.
Their outcomes after 18 months were compared with those of another 30 patients with similar baseline values for BMI, fasting plasma glucose, and hemoglobin A1c who preferred usual care, mostly oral anti-diabetic drugs as well as education on diet and exercise. Six patients were taking insulin.
Major outcomes in the two groups were as follows (P-values adjusted for age and sex or age, sex, and BMI):
- BMI: −13.5 for surgery, 0.17 for usual care (P<0.001)
- Basal glucose levels in patients with diabetes (more than 10 years): −116.2 mg/dL for surgery, −36.1 mg/dL for usual care (P=0.05)
- Basal glucose levels in patients with diabetes for (<10 years): −45 mg/dL for surgery, −30.4 for usual care (P=0.05)
- HbA1c levels in patients with diabetes (more than 10 years): −2.9% for surgery, −0.31 for usual care (P<0.001)
- More than HbA1c levels in patients with diabetes (<10 years): -1.23% for surgery, -1.24 for usual care (P≥0.05)
Final mean values in the surgery group were: BMI 28.3, fasting plasma glucose 97 mg/dL, and HbA1c 6%.
At 18 months, high-density lipoprotein (HDL) cholesterol levels also rose significantly from baseline in the surgery group (48.3 mg/dL to 61 mg/dL, P=0.014) while triglyceride levels declined (169 mg/dL to 97 mg/dL, P=0.001), whereas no significant change was seen in these parameters with usual care.
Eight of 10 patients in the surgery group who had a diabetes duration of at least 10 years remained on oral hypoglycemic drugs at the 18-month evaluation. But all 20 patients with a diabetes duration of less than 10 years were able to stop the medications.
Diabetes duration also was a predictor of differential responses in other categories among the surgical patients. For example, greater reductions in HbA1c and fasting plasma glucose levels were seen in those who had the disease for more than 10 years, compared with those with shorter diabetes duration.
Gould called the researchers' effort "a nice study" but that "by now, this kind of outcome should not come as a surprise to any bariatric surgeon. The issue now, he argued, is how to communicate these findings to patients.
He cited a recent survey showing that bariatric surgery had been recommended by primary care physicians to only about 10% of their patients with severe or morbid obesity.
The new study, Gould wrote, "demonstrates 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."
However, after the New England Journal studies appeared last month, the Endocrine Society issued a statement cautioning against routine recommendations of bariatric surgery for obese diabetic patients. The group noted that compliance with long-term lifestyle change is vital for patients undergoing bariatric surgery, and not every patient can handle it. Risks of surgery are also a consideration, the society said.
- Another study has found that bariatric surgery is a better diabetes treatment in obese patients than medical therapy.
- At 18 months, high-density lipoprotein (HDL) cholesterol levels also rose significantly from baseline in the surgery group while triglyceride levels declined.
Archives of Surgery, Leonetti F, et al "Obesity, type 2 diabetes mellitus, and other comorbidities: a prospective cohort study of laparoscopic sleeve gastrectomy vs medical treatment" Arch Surg 2012; DOI: 10.1001/archsurg.2012.222.