Retrospective Analysis of an Insulin-to-Liraglutide Switch in Patients with Type 2 Diabetes Mellitus

Insulin and the GLP-1 receptor agonist liraglutide are both effective in reaching glycemic targets. The efficacy of an insulin-to-liraglutide switch in an obese population with concurrent use of sulfonylurea and metformin is unknown. We assessed the efficacy and determinants of success of an insulin-to-liraglutide switch in these patients.

In a retrospective study we analyzed all patients that underwent an insulin-to-liraglutide switch during routine medical care (January 2009-February 2015). It was assessed if patients still continued liraglutide 12 months after the switch or discontinued because of poor glycemic control or side effects. Baseline characteristics were compared between the groups to establish determinants of success.

A total of 104 patients made an insulin-to-liraglutide switch (43% male; mean age 57.2 ± 9.9 years; mean BMI 39.8 ± 5.4 kg/m²). Sixty patients still continued liraglutide after 12 months (58%) whereas 37 patients discontinued treatment because of poor glycemic control within 12 months (36%) and seven patients discontinued liraglutide because of intolerable side effects (7%). Insulin dose and insulin frequency at baseline were significantly lower in patients that continued liraglutide. Patients reaching HbA1c ≤ 7% (53 mmol/mol) showed lower baseline HbA1c levels, shorter duration of diabetes, and shorter duration of insulin therapy.

The majority of patients continued liraglutide after a switch from insulin therapy with on average no change in glycemic control and decrease of body weight. HbA1c levels at baseline, duration of insulin therapy, and duration of diabetes were predictive of reaching glycemic control on liraglutide alone. In current practice this also indicates which patients on insulin can reduce their insulin dose after adding a GLP-1 receptor agonist. Plain language summary available for this article.