Durability of oral hypoglycemic agents in drug naïve patients with type 2 diabetes: report from the Swedish National Diabetes Register (NDR)

BMJ Open Diabetes Res Care. 2015 Mar 19;3(1):e000059. doi: 10.1136/bmjdrc-2014-000059. eCollection 2015.

Abstract

Objective: To analyze the durability of monotherapy with different classes of oral hypoglycemic agents (OHAs) in drug naïve patients with type 2 diabetes mellitus (T2DM) in real life.

Methods: Men and women with T2DM, who were new users of OHA monotherapy and registered in the Swedish National Diabetes Register July 2005-December 2011, were available (n=17 309) and followed for up to 5.5 years. Time to monotherapy failure, defined as discontinuation of continuous use with the initial agent, switch to a new agent, or add-on treatment of a second agent, was analyzed as a measure of durability. Baseline characteristics were balanced by propensity score matching 1:5 between groups of sulfonylurea (SU) versus metformin (n=4303) and meglitinide versus metformin (n=1308). HRs with 95% CIs were calculated using Cox regression models.

Results: SU and meglitinide, as compared with metformin, were associated with increased risk of monotherapy failure (HR 1.74; 95% CI 1.56 to 1.94 and 1.66; 1.37 to 2.00 for SU and meglitinide, respectively). When broken down by type of monotherapy failure, SU and meglitinide were associated with an increased risk of add-on treatment of a second agent (HR 3.14; 95% CI 2.66 to 3.69 and 2.52; 1.89 to 3.37 for SU and meglitinide, respectively) and of switch to a new agent (HR 2.81; 95% CI 2.01 to 3.92 and 3.78; 2.25 to 6.32 for SU and meglitinide, respectively). The risk of discontinuation did not differ significantly between the groups.

Conclusions: In this nationwide observational study reflecting clinical practice, SU and meglitinide showed substantially increased risk of switch to a new agent or add on of a second agent compared with metformin. These results indicate superior glycemic durability with metformin compared with SU and also meglitinide in real life.

Keywords: Oral Hypoglycaemic Agents; Pharmacoepidemiology; Type 2 Diabetes.