The incidence of obesity is rising worldwide and so are its comorbidities: type-2 diabetes mellitus (T2DM), dyslipidaemia, hypertension, cardiovascular disease, sleep apnoea, and depression. Bariatric/metabolic surgery has established itself over the past several years as an effective treatment not only for morbid obesity but also for its associated morbidities. The effects of bariatric/metabolic surgery on depression are controversial, with some studies showing improvement and others demonstrating a worsening. However, a major drawback of these studies is that they do not compare patients with the same baseline psychiatric disorders. In fact, mild to severe depressive symptoms are observed in most candidates for bariatric/metabolic surgery. Preoperative evaluation of the patient’s mental state would enable identification of the appropriate interventions, enhancing long-term compliance and weight maintenance. It could also leverage psychological support in case the patient’s disorder relapses postoperatively. Preoperative evaluation should detect potential psychological contraindications to surgery, such as severe eating disorders.
Bariatric/Metabolic Surgery for Diabetes: Lessons From the Past and Present