Study design and recruitment for a prospective controlled study of diabesity: Taiwan Diabesity Study

Summary: Background: Strong evidence has shown that metabolic surgery is more effective than medical treatment in the treatment of type 2 diabetic patients. However, no study demonstrated a survival benefit and reduction of diabetes-related end-organ damage. Here, we describe the study design of a large prospective cohort study, the Taiwan Diabesity Study (TDS) which would compare the long-term survival rate and end-organ damage between overweight/obese type 2 diabetic patients receiving metabolic surgery and medical treatment. Methods: Eligibility criteria include type 2 diabetic patients with duration > 6 months, body mass index (BMI) over 25 kg/m2 and age between 20 and 67 years. Exclusion criteria are serum creatinine over 2.0 mg/dL, C-peptide below 1.0 ng/ml, recent history of cancer, and major diabetic complications. Eligible participants were recruited from six medical centers in Taiwan. The survival rate and diabetes-related end organ damage will be compared between the metabolic surgery group and medical group after follow-up for 10 years. Results: In 3 years, 1016 participants were identified from 38,751 patients. The average BMI of patients was 30.6 (±2.6) kg/m2 and the average hemoglobin A1c was 8.2% (±1.5%) with 18% of them receiving insulin treatment. Among them, 126 patients received metabolic surgery and 890 patients received conventional medical treatment. The metabolic surgery group are younger, have a higher proportion of females, higher BMI and blood lipids as compared to the medical group. Conclusion: The TDS recruited 1016 overweight/obese type 2 diabetic patients including 126 patients receiving metabolic surgery and 890 patients receiving medical treatment. Keywords: Type 2 diabetes mellitus, Obesity, Diabesity, Metabolic surgery, Bariatric surgery, Recruitment