Medication Compliance on Glycemic Control in Patients with Elevated HbA1c

Abstract

The SIMPLE study was a randomized trial comparing two treatment strategies [basal insulin (BI) + GLP-1 RA vs. basal-bolus insulin (BBI)] in patients with T2DM and very elevated HbA1c (>10%). The glucose lowering agents were provided free of charge for the 6-month study. This post-hoc analysis evaluates compliance with the assigned glucose lowering agents, and the effect of compliance on glycemic control. Compliance was assessed by inventory of the returned medication. Optimal compliance was defined as >80% use of the respective agent over the entire duration of the study. Mixed model repeated measures analysis with compliance as a covariate was used to evaluate the treatment effect on HbA1c. The 120 randomized patients had a mean (SD) age 47.4 (9.5) years, BMI 37.2 (10.3) kg/m2, and baseline HbA1c 12.1 (1.4)%. The proportion of patients with optimal compliance with basal insulin was numerically higher in the BI+GLP-1 RA vs. BBI group (p=0.16); optimal compliance with GLP-1 RA was higher compared to bolus insulin (p=0.04) (Table). Compliance was an independent predictor for glycemic improvement (P = 0.008); treatment with BI+GLP-1 RA was superior at lowering HbA1c after adjustment for compliance (P = 0.01). Optimal compliance was low in this patient population. While compliance was a significant contributor to glycemic control, treatment with BI+GLP-1 RA improved HbA1c more than BBI independent of medication compliance.Table. Patients with optimal compliance with glucose lowering agents (>80% over the 6-month study duration) in the two treatment groups (basal insulin + GLP1 RA compared with basal-bolus insulin) and the effect of compliance on glycemic control.Basal-Bolus Insulin Group(BBI, n=56a)Basal Insulin + GLP1 RA Group (BI+GLP1 RA, n=54a)Patients with optimal compliance:Basal Insulin8 (14.3)14 (25.9)Bolus Insulin6 (10.7)NAGLP1 RANA14 (25.9)Change in HbA1c:Adjusted for compliance- 3.1 (-4.0,-2.2)- 4.5 (-5.2,-3.8)Optimal Compliance subgroup-3.2 (-4.8,-1.6)-5.4 (-6.6, -4.2)Low Compliance subgroup-3.0 (-3.7,-2.3)-3.6 (-4.4,-2.8)Data are Least squares means (95%CI) or N (%); NA - Not applicable. acompliance data available for n=110 (intention-to-treat analysis sample). Disclosure A. Elhassan: None. M. Abreu: None. A. Tumyan: None. O. Papacostea: None. K. Peicher: None. P. Dimachkie: None. M.S. Siddiqui: None. B. Adams-Huet: None. X. Li: None. L. Pop: None. I. Lingvay: Advisory Panel; Self; Novo Nordisk A/S, Eli Lilly and Company, AstraZeneca, Intarcia Therapeutics, Inc., Sanofi-Aventis. Research Support; Self; Novo Nordisk A/S, Merck Sharp & Dohme Corp., Pfizer Inc., GI Dynamics Inc., Novartis AG. Other Relationship; Self; Sanofi, AstraZeneca, Boehringer Ingelheim GmbH, Novo Nordisk A/S.