Potential benefits and harms of gastric bypass surgery in obese individuals with type 1 diabetes: a nationwide, matched, observational cohort study
Research Design and Methods: In this register‑based nationwide cohort study we compared individuals with T1D and obesity that underwent Roux‑en‑Y gastric bypass surgery (RYGB) with patients with T1D and obesity matched for age, gender, BMI and calendar time that did not undergo surgery. By linking the Swedish National Diabetes Register and Scandinavian Obesity Surgery Registry study individuals were included between 2007 and 2013. Outcomes examined included all-cause mortality, cardiovascular disease, stroke, heart failure and hospitalization for serious hypo‑ or hyperglycemic events, amputation, psychiatric disorders, changes in kidney function and substance abuse.
Results: We identified 387 individuals that had undergone RYGB and 387 controls. Follow‑up for hospitalization was up to 9 years. Analysis showed lower risk for cardiovascular disease (HR 0.43, 95% CI 0.20‑0.9), cardiovascular death (HR 0.15, 95% CI 0.03-0.68), hospitalization for heart failure (HR 0.32, 95% CI 0.15‑0.67) and stroke (HR 0.18, 95% CI 0.04-0.82) for the RYGB group. There was a higher risk for serious hyperglycemic events (HR 1.99, 95% CI 1.07‑3.72) and substance abuse (HR 3.71, 95% CI 1.03-3.29) after surgery.
Conclusion: This observational study suggests bariatric surgery may yield similar benefits on risk for cardiovascular outcomes and mortality in patients with T1D and obesity as for patients with type 2 diabetes. However, some potential serious adverse effects suggest need for careful monitoring of such patients after surgery.