Relationship between the Minnesota Living With Heart Failure Questionnaire and key ventilatory expired gas measures during exercise testing in patients with heart failure.

PURPOSE: This study assessed the relationship between the Minnesota Living With Heart Failure Questionnaire (MLWHFQ) and key ventilatory expired gas measures during a symptom-limited exercise test in the heart failure (HF) population. Specifically, is there evidence to indicate that perceived quality of life (QOL) influences exercise performance independent of physiologic function in the HF population?
METHODS: Thirty-one subjects (21 male/10 female), diagnosed with compensated HF, underwent exercise testing and completed the MLWHFQ. Mean age and left ventricular ejection fraction were 52.8 years and 27.2%, respectively. Partial correlation, controlling for age and sex, assessed the relationship between MLWHFQ (overall and subscores) and key ventilatory expired gas measures. Intraclass correlation coefficient (ICC) analysis was used to determine reliability of the MLWHFQ.
RESULTS: MLWHQ overall score (mean = 38.9, median = 36.0), physical subscore (mean = 14.8, median = 16.0), and psychosocial/symptomatology subscore (mean = 24.1, median = 19.0), were significantly correlated (P < or =.05) with peak oxygen consumption (VO2). The relationship between MLWHFQ and the minute ventilation-carbon dioxide production (VE/VCO2) slope was, however, not significant. ICC analysis revealed high reliability (0.95) for the MLWHFQ.
CONCLUSIONS: The MLWHFQ demonstrates a significant relationship with peak VO2, a measure whose validity is dependent upon subject effort. VE/VCO2 slope, which is independent of subject effort and therefore potentially a better predictor of true physiologic function, does not appear to have a relationship with perceived QOL. These findings have implications for how the MLWHFQ is assessed, related to an exercise test, and used during clinical practice.