Physician adherence to guidelines associated with improved heart failure outcomes
Physicians’ guideline adherence is associated with better prognosis in outpatients with heart failure with reduced ejection fraction: the QUALIFY international registry
The prescription of evidence-based therapies at appropriate doses, which are recommended by international guidelines, is the most effective way of ensuring that patients receive optimal care [1-4]. However, there is evidence showing that a large proportion of heart failure (HF) patients do not receive evidence-based treatments. For example, it has been reported that only a median of 27% of patients receive all HF therapies for which they are potentially eligible, and that only 42% of HF patients are discharged on angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs), beta-blockers and mineralocorticoid receptor antagonists (MRAs) .
In this analysis of the international QUALIFY survey, the impact of physicians’ adherence to guideline-recommended classes and doses of HF medications on clinical outcomes was evaluated at a 6-month follow-up. 6669 HF patients with reduced ejection fraction (HFrEF) were categorized as good adherence (23%), moderate adherence (55%) or poor adherence (22%) to 5 classes of medication (ACEIs, ARBs, beta-blockers, MRAs and ivabradine).
- Patients with a good adherence score were more likely to be Caucasian than Asian (P<0.001), had higher rates of atrial fibrillation/flutter (P<0.001), coronary artery bypass graft (P=0.002), diabetes mellitus (P<0.001), dyslipidemia (P<0.001), history of hypertension (P<0.001), history of asthma or COPD (P<0.001), chronic kidney disease (P<0.001), ≥3 co-morbidities (P<0.001) and higher BMI (P<0.001), systolic blood pressure (SBP, P<0.001) and diastolic blood pressure (DBP, P<0.001).
- A significantly higher proportion of patients with a poor adherence score had a history of cancer (P=0.043).
- The median left ventricular ejection fraction (LVEF) was comparable across all adherence groups (32.2%, 31.6% and 32.3%, respectively, P=0.004).
- In the group with poor adherence scores, significantly fewer patients were prescribed ACEIs (P<0.001), beta-blockers (P<0.001), MRAs (P<0.001), ivabradine (P<0.001), diuretics (P<0.001), anticoagulants (P<0.001) and statins (P<0.001).
- Except for beta-blockers, patients in the good adherence group had highest prescribing levels for the above classes of drugs. Beta-blockers were most commonly prescribed in the moderate adherence group.
- There was also a trend towards greater use of devices in patients in the good adherence group, with significantly more patients having implantable cardioverter-defibrillators (P=0.001).
- A good adherence score at baseline was consistently associated with better clinical outcomes after the 6-month follow-up compared with a moderate or poor adherence score.
- A poor adherence score was associated with significantly higher all-cause mortality compared with a good adherence score (HR 2.21, 95% CI: 1.42–3.44, P=0.001).
- A poor adherence score was also associated with significantly higher cardiovascular (CV) mortality (HR 2.27, 95% CI: 1.36–3.77, P=0.003), HF mortality (HR 2.26, 95% CI: 1.21–4.2, P=0.032), combined HF hospitalization or HF death (HR 1.26, 95% CI: 1.08–1.71, P=0.024) and CV hospitalization or CV death (HR 1.35, 95% CI: 1.08–1.69, P=0.013).
- There was a strong trend between a poor adherence score and HF hospitalization (HR 1.32, 95% CI: 1.04–1.68).
Good adherence of physicians to treatment guidelines, in particular prescription of ACEIs/ARBs, beta-blockers, MRAs and ivabradine, in dosages at least 50% of those recommended, is associated with improved mid-term clinical outcomes. These findings support the full implementation of guideline recommendations in clinical practice and suggest that quality performance metrics for HF in hospitals or healthcare systems should involve global adherence to all medications and dosages.