Patient-reported outcomes, as measured by the Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OS), represent a more sensitive measure than the New York Heart Association (NYHA) functional class for the assessment of clinically meaningful change in health status in patients with heart failure (HF) with reduced ejection fraction (HFrEF), a study in JAMA Cardiology suggests.
The study enrolled 2872 outpatients with chronic HFrEF (median age, 68 years) from 145 clinical practices in the US that were enrolled in the CHAMP-HF registry between 2015 and 2017. Participants in this study had complete baseline and 12-month NYHA class and KCCQ-OS data available for analysis. The investigators examined long-term changes and correlations between the two measures.
The investigators evaluated associations between improvements in NYHA and KCCQ-OS from baseline to 12 months in multivariable analyses. The multivariable models were landmarked at 12 months to study associations between the change in each measure from baseline to 12 months with clinical outcomes that occurred between 12 and 24 months. The primary outcome measures were all-cause mortality, HF hospitalization, and mortality or HF hospitalization.
The baseline distribution of patients across NYHA classes included 312 patients (10.9%) in class I, 1710 patients (59.5%) in class II, 804 patients (28.0%) in class III, and 46 patients (1.6%) in class IV.
In terms of KCCQ-OS, approximately 39.4% (n=1131) of patients scored 75 to 100, which was indicative of the best health status. Another 33.7% (n=967) of patients scored 50 to 74, 21.3% (n=612) of patients scored 25 to 49, and 5.6% (n=162) of patients scored 0 to 24, indicative of the worst health status.
At the 12-month mark, 34.9% of outpatients with HFrEF experienced a change in their NYHA class, 20.9% (n=599) showing improvement and 14.0% (n=403) showing worsening. A total of 75.1% (n=2158) of patients showed a change of ≥5 points in KCCQ-OS, with 48.3% (n=1388) showing improvement and 26.8% (n=770) showing worsening. The most common trajectories for NYHA class and KCCQ-OS were no change (65.1%) and improvement of ≥10 points (36.5%), respectively.
Improvement in NYHA class was not significantly associated with additional clinical outcomes in the adjusted analysis. However, an improvement of ≥5 points in KCCQ-OS was independently associated with reduced mortality (hazard ratio [HR], 0.59; 95% CI, 0.44-0.80; P <.001) and the combined endpoint of mortality or HF hospitalization (HR, 0.73; 95% CI, 0.59-0.89; P =.002).
A limitation of this study included the lack of a standardized range of KCCQ scores matching the 4 NYHA classes. Additionally, the cohort of this study included only patients in practices that decided to participate in the registry, which may limit the generalizability of the findings.
The investigators wrote that “the sheer magnitude of the 41% lower risk of mortality independently associated with improvement in KCCQ-OS in the present study is notable,” despite the existence of “numerous reliable clinical risk markers for HF.”
Disclosure: This clinical trial was supported by Novartis Pharmaceuticals. Please see the original reference for a full list of authors’ disclosures.
Greene SJ, Butler J, Spertus JA, et al. Comparison of New York Heart Association class and patient-reported outcomes for heart failure with reduced ejection fraction. JAMA Cardiol. Published online March 24, 2021. doi:10.1001/jamacardio.2021.0372