HOUSTON – One in five patients whose type 2 diabetes went into remission following gastric bypass surgery experienced disease re-emergence within 5 years postoperatively.
The likelihood of diabetes recurrence in this retrospective single-center study wasn’t affected by preoperative body mass index or the amount of weight regained postsurgically.
Indeed, the only significant risk factor for diabetes reemergence was a longer duration of type 2 diabetes preoperatively. Patients with a greater than 5-year preoperative history of the disease were 3.8-fold more likely to experience disease recurrence, according to Dr. Yessica Ramos of the Mayo Clinic Arizona, Scottsdale.
The clinical implication: "Early surgical intervention in the type 2 diabetic obese population may improve the durability of remission of type 2 diabetes," she said.
Dr. Ramos reported on 72 obese patients with type 2 diabetes who underwent Roux-en-Y gastric bypass at the Mayo Clinic Arizona during 2000-2007 for whom 5-year follow-up data were available. The patients’ mean preoperative body mass index was 45 kg/m2, with an average age of 49.5 years.
Sixty-six of the 72 patients (92%) experienced remission of their diabetes as defined by a hemoglobin A1c below 6.5% while off all antidiabetic medications. The other six patients had persistent type 2 diabetes throughout follow-up.
A total of 14 of 66 patients, or 21%, whose type 2 diabetes went into remission subsequently saw their disease return as defined by an HbA1c of 6.5% or more, a fasting blood glucose greater than 7 mmol/L, or use of antidiabetic drugs.
Diabetes returned as early as 2 years post surgery in five patients.
The explanation for the high rate of diabetes reemergence remains unclear. Retrospective studies of bariatric surgery patients are notoriously difficult because the surgery is often life changing and patients are frequently lost to follow-up.
Dr. Ramos’s working hypothesis is that patients with longer duration of type 2 diabetes are at a higher risk of recurrence because they have more compromised beta cell function. But definitive answers must await further reports from prospective randomized trials of surgery vs. medication as a treatment for type 2 diabetes in obese patients, such as the one reported from the Cleveland Clinic (N. Engl. J. Med. 2012;366:1567-76), or analysis of data from the large multicenter bariatric surgery registries.
Dr. Ramos reported having no financial conflicts.