Obesity, type 2 diabetes mellitus, and other comorbidities: a prospective cohort study of laparoscopic sleeve gastrectomy vs medical treatment.

OBJECTIVE To compare the effect of sleeve gastrectomy vs medical therapy on type 2 diabetes mellitus and other obesity-related comorbidities (obstructive sleep apnea syndrome, hypertension, and dyslipidemia) in prospectively enrolled and matched obese patients with type 2 diabetes. DESIGN A prospective cohort study. Morbidly obese patients with type 2 diabetes who either underwent sleeve gastrectomy or conventional therapy were followed up and assessed for their diabetic state and other comorbidities every 3 months for 18 months. SETTING Centre for the Surgical-Medical Treatment of Morbid Obesity, Policlinico “Umberto I,” University of Rome “Sapienza,” Italy. PATIENTS A total of 30 morbidly obese patients with type 2 diabetes who underwent sleeve gastrectomy (group A) and a total of 30 morbidly obese patients with type 2 diabetes who underwent conventional therapy (group B). RESULTS In group A, the preoperative mean (SD) body mass index, fasting plasma glucose level, and hemoglobin A1c level were 41.3 (6.0), 166.6 (68.1) mg/dL, and 7.9% (2.1%), respectively, and, at 18 months, these values were 28.3 (5.4), 96.2 (29.4) mg/dL, and 6.0% (1.5%), respectively. For 80% of patients, diabetes was resolved. With regard to other comorbidities, the prevalence of obstructive sleep apnea syndrome dropped from 50% to 10%, and patients reduced significantly their use of medication for hypertension and dyslipidemia. In group B, the preoperative mean (SD) body mass index, fasting plasma glucose level, and hemoglobin A1c level were 39.0 (5.5), 183.7 (63.5) mg/dL, and 8.1% (1.7%), respectively, and, at 18 months, these values were 39.8 (5.0), 150 (48) mg/dL, and 7.1% (1.3%), respectively. All patients remained diabetic and continued or increased their level of hypoglycemic therapy. With regard to other comorbidities, we observed an increase in the use of medication for hypertension and dyslipidemia, and the prevalence of obstructive sleep apnea syndrome did not change. CONCLUSIONS This study confirms the efficacy of sleeve gastrectomy in the treatment of morbidly obese type 2 diabetic patients when compared with conventional medical treatment.