RESUMEN
AIMS: The study aims to examine real-world weight change and the role of medication adherence among patients with type 2 diabetes who initiated one of three drug classes: glucagon-like peptide-1 receptor agonist (GLP-1RA), dipeptidyl peptidase-4 inhibitor (DPP4) and sulfonylureas (SUs). MATERIALS AND METHODS: A cohort of patients initiating one of the three drug classes was selected from a large US database of integrated electronic medical record and administrative claims. Adherence was defined as per cent of days covered ≥80% during the year following drug initiation. Weight change was calculated from drug initiation (-180, +30 d) to 1 year (±90 d) later. Multivariate regression controlled for baseline differences between adherent and poorly adherent patients and the addition of another drug class during follow-up. RESULTS: The study included 833 GLP-1RA, 2,272 DPP4 and 2,713 SU patients who contributed 2,279, 6,602 and 7,429 observations respectively. Patients initiating a GLP-1RA achieved the largest weight change (-2.46 kg of GLP-1RA, -1.26 kg of DPP4 and 0.18 kg of SU, P < 0.01). Adherent GLP-1 patients lost 1.73 kg more than poorly adherent patients, and adherent SU patients gained 1.11 kg more than poorly adherent patients (all P < 0.01). Adherent and poorly adherent DPP4 patients experienced approximately the same amount of weight loss. CONCLUSIONS: Medication adherence can mediate observed weight loss in patients treated with a GLP1-RA or weight gain in those treated with an SU. Medication adherence was low in a real-world population, particularly for GLP-1RA, which displayed the strongest weight loss benefit. Because recent American Diabetes Association guidelines recommend selecting drug therapies that have a weight loss or weight neutral effect for the management of type 2 diabetes patients, patients should be encouraged to enhance their adherence to benefit the most from therapies that have weight loss properties.