Metabolic surgery for inadequately controlled type 2 diabetes in nonseverely obese Japanese: a prospective, single-center study.

Background: The beneficial effects of metabolic surgery on weight loss, glycemic control, and cardiovascular improvement for the morbidly obese patient has been vast and undeniable. It is also expected to be effective in diabetic patients with less severe obesity, but the evidence is yet to yield significant impact.

Objective: In this study, we investigate the impact of metabolic surgery on inadequately controlled type 2 diabetes in Japanese patients with mild obesity.

Setting: Private practice, Japan.

Methods: Twenty-eight consecutively selected diabetic patients with body mass index 27.5 to 34.9 kg/m, who had inadequately controlled diabetes despite intensive medical treatments, underwent laparoscopic sleeve gastrectomy with duodenojejunal bypass, and were prospectively followed up for 12 months. The primary endpoint was a composite of proposed parameters of optimal diabetes management of glycosylated hemoglobin (HbA1C)<7.0%, low-density lipoprotein cholesterol<100 mg/dL, and systolic blood pressure<130 mm Hg.

Results: At enrollment, the HbA1C was 9.4 ± 1.3% and the duration of diabetes was 11.7 ± 7.4 years. After the short-term low-calorie diet intervention, the preoperative baseline body mass index and HbA1C were 31.0 ± 1.5 kg/m and 8.5 ± 1.3%, respectively. At 1 year, body mass index and HbA1C dropped to 24.7 ± 2.3 kg/m and 6.8 ± .8%, respectively. Those who achieved HbA1C<6.5% without diabetes medications, and those with HbA1C<7% were 23% and 54% compared with 0% and 3.6% at baseline (P = .007 and P<.001), respectively. Although the ratio of those who achieved the composite endpoint did not reach statistical significance, positive impacts were also observed on hypertension, dyslipidemia, medication usage, and quality of life. There were 3 major surgical morbidities and no mortalities.

Conclusions: Gastrointestinal metabolic surgery in nonmorbidly obese Japanese with inadequately controlled type 2 diabetes may have additional metabolic benefits.