Comparative Effectiveness of Dosing of Medical Therapy for Heart Failure: From the CHAMP-HF Registry

Background: The comparative effectiveness of differing dosages of guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) on clinical and patient-reported outcomes in clinical practice in the United States is unknown. This study sought to characterize associations between the dosing of GDMT and outcomes for patients with HFrEF in U.S. clinical practice. Methods: This analysis included 4832 outpatients who had chronic HFrEF across 150 practices in the U.S. in the Change the Management of Patients with Heart Failure (CHAMP-HF) registry with no contraindication and available dosing data for at least 1 GDMT at baseline. Baseline dosing of angiotensin-converting enzyme (ACEI)/angiotensin II receptor blocker (ARB)/angiotensin receptor-neprilysin inhibitor (ARNI), beta-blocker, and mineralocorticoid receptor antagonist (MRA) therapies were examined. For each medication class, multivariable models assessed associations between medication dosing and clinical outcomes over 24 months (all cause mortality, HF hospitalization) and patient-reported outcomes at 12 months (change in the Kansas City Cardiomyopathy Questionnaire Overall Summary score [KCCQ-OS]). Results: After adjustment, compared with target dosing, lower dosing was associated with higher all-cause mortality for ACEIs/ARBs/ARNIs (50% to < 100% target dosage, HR 1.16 [95% CI 0.87-1.55]; < 50% target dosage, HR 1.37 [95% CI 1.05-1.79]; none, HR 1.75 [95% CI 1.32-2.34; overall P< 0.001) and beta-blockers (50% to < 100% target dosage, HR 1.30 [95% CI 1.00-1.69]; < 50% target dosage, HR 1.41 [95% CI 1.11-1.79; none, HR 1.24 [95% CI 0.92-1.67]; overall P= 0.042). Lower dosing of ACEIs/ARBs/ARNIs was independently associated with higher risk of HF hospitalization (50% to < 100% target dosage, HR 1.08 [95% CI 0.90-1.30]; < 50% target dosage, HR 1.23 [1.04-1.47]; none, HR 1.29 [1.04-1.60]; overall P= 0.046), but beta-blocker dosing was not (overall P= 0.085). Target dosing of MRAs was not associated with risk of mortality or HF hospitalization. For each GDMT, compared with target dosing, lower dosing was not associated with change in the KCCQ-OS at 12 months, with the potential exception of worsening KCCQ-OS scores with lower dosing of ACEIs/ARBs/ARNIs. Conclusions: In this contemporary U.S. outpatient HFrEF registry, target dosing of ACEI/ARB/ ARNI and beta-blocker therapy was associated with reduced mortality and was variably associated with HF hospitalization and patient-reported outcomes. MRA dosing was not associated with outcomes. The totality of these findings support the benefits of target dosing of GDMT in routine practice, as tolerated, with unmeasured differences among patients receiving differing dosages potentially explaining the differing results seen here compared with randomized clinical trials.