Comparison of New York Heart Association Class and Patient-Reported Outcomes for Heart Failure With Reduced Ejection Fraction

Importance

It is unclear how New York Heart Association (NYHA) functional class compares with patient-reported outcomes among patients with heart failure (HF) in contemporary US clinical practice.

Objective

To characterize longitudinal changes and concordance between NYHA class and the Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OS), and their associations with clinical outcomes.

Design, Setting, and Participants

This cohort study included 2872 US outpatients with chronic HF with reduced ejection fraction across 145 practices enrolled in the CHAMP-HF registry between December 2015 and October 2017. All patients had complete NYHA class and KCCQ-OS data at baseline and 12 months. Longitudinal changes and correlations between the 2 measure were examined. Multivariable models landmarked at 12 months evaluated associations between improvement in NYHA and KCCQ-OS from baseline to 12 months with clinical outcomes occurring from months 12 through 24. Statistical analyses were performed from March to August 2020.

Exposure

Change in health status, as defined by 12-month change in NYHA class or KCCQ-OS.

Main Outcomes and Measures

All-cause mortality, HF hospitalization, and mortality or HF hospitalization.

Results

In total, 2872 patients were included in this analysis (median [interquartile range] age, 68 [59-75] years; 872 [30.4%] were women; and 2156 [75.1%] were of White race). At baseline, 312 patients (10.9%) were NYHA class I, 1710 patients (59.5%) were class II, 804 patients (28.0%) were class III, and 46 patients (1.6%) were class IV. For KCCQ-OS, 1131 patients (39.4%) scored 75 to 100 (best health status), 967 patients (33.7%) scored 50 to 74, 612 patients (21.3%) scored 25 to 49, and 162 patients (5.6%) scored 0 to 24 (worst health status). At 12 months, 1002 patients (34.9%) had a change in NYHA class (599 [20.9%] with improvement; 403 [14.0%] with worsening) and 2158 patients (75.1%) had a change of 5 or more points in KCCQ-OS (1388 [48.3%] with improvement; 770 [26.8%] with worsening). The most common trajectory for NYHA class was no change (1870 [65.1%]), and the most common trajectory for KCCQ-OS was an improvement of at least 10 points (1047 [36.5%]). After adjustment, improvement in NYHA class was not associated with subsequent clinical outcomes, whereas an improvement of 5 or more points in KCCQ-OS was independently associated with decreased mortality (hazard ratio, 0.59; 95% CI, 0.44-0.80;P < .001) and mortality or HF hospitalization (hazard ratio, 0.73; 95% CI, 0.59-0.89;P = .002).

Conclusions and Relevance

Findings of this cohort study suggest that, in contemporary US clinical practice, compared with NYHA class, KCCQ-OS is more sensitive to clinically meaningful changes in health status over time. Changes in KCCQ-OS may have more prognostic value than changes in NYHA class.