Changes in recorded background glucose-lowering therapy after initiation of a GLP-1 receptor agonist or dual GIP/GLP-1 receptor agonist in adults with type 2 diabetes.

AIMS: To evaluate changes in recorded background glucose-lowering active-substance counts after initiation of a glucagon-like peptide-1 (GLP-1) or dual GIP/GLP-1 receptor agonist. METHODS: This retrospective cohort study used anonymized electronic health records from a large Polish private outpatient network. Adults with type 2 diabetes (ICD-10 E11 without E10) initiating semaglutide, liraglutide, dulaglutide, or tirzepatide, with at least one recorded baseline non-GLP-1 glucose-lowering active substance, were included. Using medication-specific dates, substances were classified as baseline (before index) or subsequently recorded (on or after index), and within-patient change as a lower count, no change, or a higher count. RESULTS: Among 3,660 patients (median age, 60 years; 53.9% women), the median recorded count rose from 1 [interquartile range, 1-2] to 2 [1-3], though the median within-patient change was 0 [0-1]. A lower count occurred in 17.2% of patients, no change in 38.8%, and a higher count in 44.0%, most frequently with dulaglutide (52.9%) and least with tirzepatide (20.4%). CONCLUSIONS: After medication-date validation, a higher count was more common than a lower count, though it occurred in fewer than half of patients. These findings describe prescription-record patterns and do not establish concomitant exposure, treatment intensity, or a causal effect.