Introduction: The incidence of type 2 diabetes mellitus (T2DM) is increasing, in parallel with the epidemic of obesity. Although bariatric surgery, which profoundly affects T2DM, has increased 10-fold since the millennium, only a fraction of diabetics is offered this treatment option.Objective: To investigate the association between clinical and socioeconomic factors in selecting patients with T2DM for bariatric surgery in a publicly financed healthcare system.Research design and methods: Cohort study using prospectively registered data from two nationwide quality registers, the Scandinavian Obesity Surgery Registry (SOReg) and the Swedish National Diabetes Register (NDR), and data from two government agencies. An age, gender and body mass index-matched case-control analysis containing 10 642 patients with T2DM was performed.Results: Patients with T2DM having bariatric surgery had a higher education level (upper secondary school or college level, OR 1.42% and 95% CI (1.29 to 1.57) and 1.33 (1.18 to 1.51), respectively) as well as a higher income (OR 1.37 (1.22 to 1.53) to 1.94 (1.72 to 2.18) for quartile 2-4) than non-operated patients. Operated patients were more often married or had been married (OR 1.51 (1.37 to 1.66) and 1.65 (1.46 to 1.86), respectively) as well as natives (OR 0.84 (0.73 to 0.95) if born in the rest of Europe). Groups did not differ regarding relevant laboratory data and present medication, nor in former in-patient diagnoses.Conclusion: Despite similar clinical data, superior socioeconomic status was associated with increased rate of bariatric surgery in patients with T2DM. We believe that this warrants actions, for example concerning referral patterns.
