Drug Adherence After Hospitalisation for Heart Failure: What Have We Learned from a French Survey?

Background: Despite significant advances in heart failure (HF) management, mortality and readmission rates remain persistently high. Low adherence has been recognised as a contributing factor, although supporting data remain limited. Objective: This study aimed to evaluate the impact of medication adherence on outcome following a HF hospitalisation. Methods: Patients who were discharged after HF hospitalisation were included in the study from a national multicentre HF cohort, and their records were matched with the National Healthcare System database, which includes all health-related claims and clinical events. Adherence to beta blockers, renin-angiotensin system inhibitors, and mineralocorticoid receptor antagonists were measured using the proportion of days covered (PDC). Low adherence was defined by PDC < 80% for at least one of the three HF drug classes. We then analysed the relationship between the PDC and outcome during a two-year follow-up period. Results: A total of 448 patients (median age: 73 years; 67% male; mean ejection fraction: 40%) were included. Of these patients, 152 (34%) were classified as having low adherence. The two-year mortality rate was comparable between the two groups (16.9% vs. 19.1% in adherent and low-adherent groups, respectively, p = 0.6). However, the rates of all-cause and HF rehospitalisations at two years were lower in the adherent group than in the group with low adherence (85.9% vs. 92.8%, p ≤ 0.01; 48.5% vs. 58.2%, p = 0.04, respectively). Conclusions: In patients discharged after acute HF, low adherence to HF drugs is frequent and worsens outcome, particularly the risk of rehospitalisation.