In a new study entitled “Bariatric–metabolic surgery versus conventional medical treatment in obese patients with type 2 diabetes: 5 year follow-up of an open-label, single-centre, randomized controlled trial,” scientists show that weight loss surgery is a more effective strategy when compared to standard methods in the long-term control of type 2 diabetes in obese patients. The study was published in the prestigious research journal Lancet.
Several studies have shown that bariatric surgery (weight loss surgery) is an effective strategy for short-term control of type 2 diabetes when compared to conventional treatments. However, how bariatric surgery impacts type 2 diabetes in obese patients in the long run was unknown.
A group of scientists at King’s College London and the Universita Cattolica in Rome, Italy performed a randomized control trial where a group of diabetic patients (with a body-mass index of at least 35 kg/m2) was randomly assigned to receive one of three possible treatments for type two diabetes: conventional medical treatment (20 patients) or surgery by gastric bypass (20) or biliopancreatic diversion (20). Out of 60 initial patients recruited, 53 completed a five-year follow-up in which scientists determined for how long patients’ diabetes remained in remission (defined in this study as a glycated hemoglobin A1c (HbA1c) concentration of 6.5% or less (≤47.5 mmol/mol) and a fasting glucose concentration of 5.6 mmol/L or less, without treatment intervention for at least 1 year).
Additional parameters included glycemic and metabolic control, cardiovascular risk, and the use of medication (glucose-lowering drugs and insulin or blood pressure and lipid-lowering drugs); quality of life, and surgery-associated long-term complications.
The team observed that 50% of the patients treated with surgery maintained diabetes remission at 5 years when compared to none of the 15 medically treated patients. All surgery-treated patients exhibited better performance at controlling diabetes, irrespective of type of surgery, when compared to medication group. Additionally, weight loss surgery patients had a significantly lower risk (50% less) of cardiovascular risk after 5 years and had overall better qualify of life. While five major diabetic complications were detected in the medical treated group, no mortality and major complications arose in the surgery treated groups.
When comparing both surgical procedures, biliopancreatic diversion patients had higher remission rates of diabetes in comparison to the gastric bypass at year 5, 67% versus 37%, respectively. The latter study group, however, had fewer nutrition issues and better quality of life scores. As a result, gastric bypass may present increased benefits in the diabetic population for controlling the disease
The authors highlight that their findings suggest surgery is a more effective strategy for a long-term control of obese patients with type 2 diabetes. However, they note that since half of the patients who experienced initial diabetes remission after surgery relapsed to mild hyperglycemia at year five, there is a need for continuous monitoring of glycemia in this patient population.
Professor Francesco Rubino, senior author of this study and Chair of Bariatric and Metabolic Surgery at King’s College London and a Consultant Surgeon at King’s College Hospital in London, UK and study lead author commented, “The ability of surgery to greatly reduce the need for insulin and other drugs suggests that surgical therapy is a cost-effective approach to treating type-2 diabetes. The results of this study add to a growing body of evidence showing that the gastrointestinal tract is a rational biological target for antidiabetic interventions and support implementation of surgery as a standard option in the treatment of type 2 diabetes.”
Professor Geltrude Mingrone, study first author and Professor of Internal Medicine at the Universita Cattolica in Rome and Professor of Diabetes and Nutrition at King’s College London added, “The lower incidence of typical diabetes complications in this study is in line with previous findings from long-term non-randomized studies; however, larger and ideally multicenter randomized trials are needed to definitively confirm that surgery can reduce diabetes morbidity and mortality compared to standard medical treatment. Nevertheless, surgery appears to dramatically reduce risk factors of cardiovascular disease.”