Objective: Data are sparse regarding the survival benefit of bariatric surgery on mortality among persons with diabetes. We aimed to investigate the association of bariatric surgery, compared with usual care, on all-cause mortality in individuals who underwent surgery and matched controls, stratified by the presence of diabetes.
Research design and methods: This retrospective cohort study utilized population-based electronic medical record data. Individuals who underwent one of three types of bariatric surgery during 2005-2014 were included. For each surgical patient, three non-surgical individuals were matched according to age, sex, body mass index, and diabetes status. The cohort comprised 9564 individuals with diabetes and 23,976 individuals without diabetes.
Results: During a median follow-up of 4.2 years, adjusted hazard ratios (HRs) for mortality for non-surgery vs. surgery were 2.38 (95%CI: 1.75, 3.26) and 1.73 (95%CI: 1.26, 2.36) among individuals with diabetes and individuals without diabetes, respectively. Considered separately, HRs for mortality for laparoscopic banding, gastric bypass, and laparoscopic sleeve gastrectomy were 2.83 (95%CI: 1.73, 4.63), 2.30 (95%CI: 1.25, 4.25), and 1.89 (95%CI: 1.1, 3.32) among patients with diabetes; and 1.74 (95%CI: 1.20, 2.52), 2.66 (0.81, 8.76), and 1.16 (0.51, 2.65) among patients without diabetes.
Conclusion: The survival advantage of bariatric surgery after a median follow-up of 4.2 years was greater among individuals with than without diabetes for the three types of surgery performed. Longer follow-up is needed to examine the effect on survival in individuals without diabetes who undergo bariatric surgery. These results suggest priority considerations for bariatric surgery candidates.
Keywords: Bariatric surgery; Diabetes; Gastric banding; Mortality; Roux-en-Y gastric bypass; Sleeve gastrectomy; Subgroups.