Aims
Medication non-adherence post-discharge is common among patients, especially those suffering from chronic medical conditions, and contributes to hospital admissions and mortality. This study aimed to evaluate the effect of the Cardiac Care Bridge (CCB) intervention on medication adherence post-discharge.

Methods
We performed a secondary analysis of the CCB randomized single-blind trial, a study in patients ≥70 years, at high risk of functional loss and admitted to cardiology departments in six hospitals. In this multi-component intervention study, community nurses performed medication reconciliation and observed medication-related problems (MRPs) during post-discharge home visits, and pharmacists provided recommendations to resolve MRPs. Adherence to high-risk medications was measured using the proportion of days covered (PDC), using pharmacy refill data. Furthermore, MRPs were assessed in the intervention group.

Results
For 198 (64.7%) of 306 CCB patients, data were available on adherence (mean age: 82 years; 58.9% of patients used a multidose drug dispensing [MDD] system). The mean PDC before admission was 92.3% in the intervention group (n = 99) and 88.5% in the control group (n = 99), decreasing to 85.2% and 84.1% post-discharge, respectively (unadjusted difference: −2.6% (95% CI −9.8 to 4.6, P = .473); adjusted difference −3.3 (95% CI −10.3 to 3.7, P = .353)). Post-hoc analysis indicated that a modest beneficial intervention effect may be restricted to MDD non-users (P interaction = .085). In total, 77.0% of the patients had at least one MRP post-discharge.

Conclusions
Our findings indicate that a multi-component intervention, including several components targeting medication adherence in older cardiac patients discharged from hospital back home, did not benefit their medication adherence levels. A modest positive effect on adherence may potentially exist in those patients not using an MDD system. This finding needs replication.