Weight beneficial treatments for type 2 diabetes

The close link between type 2 diabetes and excess body weight highlights the need to consider the weight effects of different treatment regimens. We examine the impact of "weight-friendly" type 2 diabetes pharmacotherapies and suggest treatment strategies that mitigate weight gain.

Evidence was identified via PubMed search by class and agent and in bibliographies of review articles, with final articles for inclusion selected by author consensus.

Substantial evidence confirms the weight benefits of metformin and shows that, of the newer available agents, glucagon-like peptide-1 (GLP-1) agonists and amylin analogs promote weight loss. Dipeptidyl peptidase-4 (DPP-4) inhibitors and bile acid sequestrants are weight-neutral. Liraglutide and exenatide appear to have similar effects on weight; however, recent research suggests a potentially greater effect of liraglutide on glycemic control compared to exenatide, when used as a second-line therapy. Mounting evidence suggests that insulin detemir may provide the most favorable weight benefits of available insulins.

Weight-beneficial agents should be considered in patients, particularly obese patients, who fail to reach glycemic targets on metformin therapy. We propose the following treatment choices based on potential weight benefit and blood glucose increment: long-acting GLP-1 agonists (liraglutide), DPP-4 inhibitors, bile acid sequestrants, amylin analogs, and basal insulin for patients with elevated fasting plasma glucose; and short-acting (exenatide) or long-acting GLP-1 agonists, amylin analogs, DPP-4 inhibitors, acarbose, and bile acid sequestrants for patients with elevated postprandial glucose. The weight-sparing effects of insulin detemir, notably in patients with high body mass index, should also be considered when initiating insulin therapy.