Can a protocol for glycaemic control improve type 2 diabetes outcomes after gastric bypass?

Roux-en-Y gastric bypass surgery (RYGB) is an effective treatment for patients with type 2 diabetes (T2DM). Tight glycaemic control immediately after RYGB for T2DM may improve long-term glycaemic outcomes, but is also associated with a higher risk of hypoglycaemia. We designed a treatment algorithm to achieve optimal glycaemic control in patients with insulin-treated T2DM after RYGB and evaluated its feasibility, safety and efficacy.

Fifty patients following protocol-driven diabetes management were discharged on a fixed amount of metformin and glargine, with the insulin dose adjusted according to a standardised insulin sliding scale aiming for a fasting capillary glucose (FCG) of 5.5-6.9 mmol/L. Glycaemic outcome and remission of diabetes (defined as HbA1c < 6% and FCG levels < 5.6 mmol/L for at least 1 year without hypoglycaemic medication) were compared between patients who received protocol-driven treatment and a similar cohort of 49 patients following standard glycaemic management.

At 1 year follow-up, the protocol-driven group showed a greater improvement in glycaemic control than the non-protocol-driven group (HbA1c -3.0 ± 0.2% vs. -1.2 ± 0.1%, P < 0.001; FCG levels -3.4 ± 0.2 vs. -2.0 ± 0.2 mmol/L, P = 0.02) and a higher remission rate from T2DM (50.0% vs. 6.1%, P < 0.001). No symptomatic hypoglycaemia was reported in either group.

The protocol-driven management proved to be feasible, safe and effective in achieving targeted glycaemic control in T2DM after RYGB. The next step will be to scrutinise the efficacy of protocol-driven management in a randomised controlled clinical trial.