Unawareness of being prescribed medications for diabetes and incident cardiovascular disease

Background Some patients with diabetes are unaware that they are prescribed medications for diabetes. The purpose of this study is to determine, using a Japanese nationwide epidemiologic database, the association between unawareness of being prescribed medication and the risk of developing cardiovascular disease (CVD) in patients with diabetes. Methods This observational cohort study analyzed data from the JMDC Claims Database between 2005 and 2022, including 94,048 patients with diabetes treated with medications. The primary endpoint was a composite endpoint including myocardial infarction (MI), stroke, heart failure (HF), and atrial fibrillation (AF). Results We identified 7561 composite CVD endpoints during a mean follow-up of 1199 ± 902 days. Overall, 7779 (8.3 %) patients were unaware of being prescribed medications for diabetes. Those who did not know they were prescribed drugs were younger and had better glycemic control, but these individuals were at higher risk of developing combined CVD [hazard ratio (HR) 1.13, 95 % confidence interval (95 % CI) 1.04–1.22]. HRs of unawareness of being prescribed medications were 1.33 (95 % CI 1.06–1.68) for MI, 1.13 (95 % CI 0.97–1.31) for stroke, 1.10 (95 % CI 1.00–1.21) for HF, and 1.19 (95 % CI 0.97–1.47) for AF, respectively. Conclusions In patients with diabetes taking medications for diabetes, even if they are young and have good glycemic control, it is important that they receive adequate education from their healthcare providers to accurately identify their treatment status.