Timing of heart failure diagnosis and uptake of newly recommended therapies following clinical guideline updates

Background Clinical guideline updates aim to ensure that patients benefit from emerging evidence, yet it is unclear whether patients with established chronic disease receive newly recommended therapies as readily as those diagnosed after guideline updates. We examined uptake of angiotensin receptor–neprilysin inhibitors (ARNi) and sodium-glucose co-transporter 2 inhibitors (SGLT2i) among patients diagnosed with heart failure before and after relevant guideline updates. Methods Using Danish nationwide registry data, we followed patients with a primary diagnosis of heart failure from diagnosis until first redeemed prescription, death, emigration or 30 June 2022. Separate analyses were performed for ARNi and SGLT2i following their introduction into clinical guidelines. Adjusted cause-specific HRs for first prescription redemption were estimated using Cox proportional hazards models with delayed entry and accounting for the competing risk of death. Results The ARNi analysis included 17 335 patients diagnosed before and 43 625 diagnosed after the guideline update. The SGLT2i analysis included 18 056 and 5109 patients, respectively. After adjustment for demographic, clinical and socioeconomic characteristics, patients diagnosed before guideline updates were less likely to redeem a prescription for ARNi (HR 0.57, 95% CI 0.51 to 0.63) or SGLT2i (HR 0.72, 95% CI 0.66 to 0.79) than those diagnosed after the respective guideline updates. Conclusions Patients diagnosed with heart failure before major guideline updates had lower uptake of newly recommended therapies than patients diagnosed afterwards. These findings suggest that publication of updated clinical guidelines alone may be insufficient to ensure timely implementation for patients with established disease and highlight the need for systematic approaches to review treatment following major guideline changes.