The Relationship Between Timing of Initiation on a Glucagon-like Peptide-1 Receptor Agonist and Glycosylated Hemoglobin Values Among Patients With Type 2 Diabetes

PurposeThis study examines the relationship between timing of initiation on a glucagon-like peptide-1 receptor agonist (GLP-1 RA) and glycosylated hemoglobin (HbA_1c) values.MethodsThe IBM MarketScan databases were used to identify adults with type 2 diabetes mellitus (T2DM) who initiated GLP-1 RA therapy and had multiple recorded HbA_1c results. Time to GLP-1 RA initiation was proxied by the number of classes of glucose-lowering agents prescribed in the 2 years before GLP-1 RA initiation, with fewer glucose-lowering agents indicating initiation of a GLP-1 RA earlier in disease progression. Paired t tests examined differences in HbA_1c values from preperiod to 2-year postperiod. Multivariable analyses examined the relationship between time to GLP-1 RA initiation and postperiod HbA_1c values.FindingsInitiation on a GLP-1 RA was associated with a 0.6% reduction in HbA_1c values over 2 years (P < 0.0001). Earliest starts were associated with a 1.3% reduction in HbA_1c levels (P < 0.0001) and the highest likelihood of achieving a postperiod HbA_1c level <7% (odds ratio, 4.9; 95% CI, 3.0–8.1).ImplicationsResults indicate that although initiation on a GLP-1 RA is generally associated with reduced HbA_1c levels, there may be additional clinical benefits associated with earlier initiation of a GLP-1 RA.