Analysis of patient-specific factors contributing to effectiveness of glucagon-like peptide-1 receptor agonists

Glucagon-like peptide-1 receptor (GLP-1) agonists are antidiabetic medications used to improve hemoglobin A1c (HbA1c) and promote weight loss. Per the Veterans Affairs/Department of Defense guidelines for the management of type 2 diabetes, GLP-1 agonists are expected to lower HbA1c by 1%-1.5%. The clinical pharmacy specialist in the women’s health primary care clinic at the Louis A. Johnson Veterans Affairs Medical Center noted cases of women started on GLP-1 agonists achieving greater than expected HbA1c reduction. The primary objective of this study was to determine if there are any patient-specific factors that may increase the effectiveness of GLP-1 agonists. Secondary objectives included an analysis of average weight and HbA1c, use of the Pearson rank correlation test to determine if there is a correlation between weight change and HbA1c reduction, and an analysis of HbA1c reduction associated with each GLP-1 agonist prescribed. A retrospective chart review was conducted. Data collected from the charts included age, sex, height, GLP-1 agonist prescribed, and HbA1c and weight before and after GLP-1 agonist initiation. For primary outcomes, statistical analyses were run between 2 groups: patients who had an HbA1c reduction of greater than 1.5% and patients who had an HbA1c reduction less than or equal to 1.5%. Women were more likely to have an HbA1c reduction of greater than 1.5% (P = 0.001). Patients with a lower baseline weight were more likely to attain an HbA1c reduction greater than 1.5% (P = 0.045). Higher baseline HbA1c was correlated with an increased likelihood of HbA1c reduction greater than 1.5% (P = 0.001). GLP-1 agonists may be more effective at reducing HbA1c in female patients, those with a lower baseline weight, and those with a higher baseline HbA1c.