Patient and physician factors driving the gaps in use of drugs with cardiovascular and kidney benefits by medicare beneficiaries with type 2 diabetes treated by endocrinologists, nephrologists, and cardiologists: Population-based cohort study

AIMS: Endocrinologists, nephrologists, and cardiologists care for people with type 2 diabetes (T2D) and coexisting cardiovascular disease (CVD), heart failure (HF), and/or chronic kidney disease (CKD). Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) should be preferentially used, but are underutilized. We examine patient and physician factors associated with GLP-1RA/SGLT2i use by patients treated by these subspecialists. METHODS: Retrospective cohort study using linked 2022 Medicare and American Board of Internal Medicine data for adults >65 years with T2D and coexisting CVD, HF, and/or CKD and their treating endocrinologists, nephrologists, and cardiologists. RESULTS: We identified 246,106/254,425/435,773 patients treated by 5,661/8,233/10,874 endocrinologists/nephrologists/cardiologists in 2022. Overall, 73.2 % of endocrinologist-treated patients filled diabetes medications prescribed by endocrinologists; 41.9 % filled GLP-1RA/SGLT2i. Patients of nephrologists and cardiologists were rarely prescribed diabetes medications by these subspecialists (9.8 % and 6.1 %, respectively); however, conditional on filling any diabetes medication, they were more likely to fill a GLP-1RA/SGLT2i (59.5 % and 48.2 %, respectively). Older patients of endocrinologists and nephrologists, and patients of older nephrologists and cardiologists, were less likely to fill GLP-1RA/SGLT2i. CONCLUSIONS: Many, particularly older, patients with T2D treated by endocrinologists, nephrologists, and cardiologists should be, but are not, prescribed GLP-1RA/SGTL2i. Physician training may improve these statistics.