Abstract 1113: What Happens When Heart Failure Patients Don’t Know What They Don’t Know
Background: Medication adherence produces better outcomes in patients (pts) with heart failure (HF). Clinicians depend on pt self-report of adherence, but the consequences of inaccurate self-report are unknown.
Purpose: To determine the impact on event-free survival of the concordance of pts’ self-report of adherence with objectively measured adherence.
Methods: Adherence was assessed objectively for 3 months using the Medication Event Monitoring System (MEMS) in 135 (age 61±11years; 30% female) HF pts. Pts were considered adherent if they took ≥89% of prescribed doses during monitoring. Pts’ self-reported their adherence using the Medical Outcomes Study Adherence Scale. Pts were placed in 1 of 4 groups based on the concordance of their self-reported adherence with actual adherence:
realistic non-adherers (accurately assessed their non-adherence);
over-confident non-adherers (thought they were more adherent than they were);
realistic adherer s (accurately assessed their adherence); and
under-confident adherers (adherent but thought their adherence was low).
Results: Using Cox regression and controlling for age, gender, NYHA class, medications and depression, pt group predicted event-free survival (p=0.005; Figure⇓). The worst event-free survival was seen in over-confident non-adherers who had 3.4 times greater risk for earlier events than realistic adherers (p=0.002).
Conclusion: Non-adherence is associated with worse event-free survival, but the worst outcomes are seen in pts unrealistic about their non-adherence who believe themselves to be more adherent than they are. Depending on pt self-report of adherence may have negative consequences.