Outcomes, health policy, and managed care: relationships between patient-reported outcome measures and clinical measures in outpatients with heart failure

Am Heart J. 2009 Oct;158(4 Suppl):S64-71. doi: 10.1016/j.ahj.2009.07.010.

Abstract

Background: Patient-reported outcomes are increasingly used to assess the efficacy of new treatments. Understanding relationships between these and clinical measures can facilitate their interpretation. We examined associations between patient-reported measures of health-related quality of life and clinical indicators of disease severity in a large, heterogeneous sample of patients with heart failure.

Methods: Patient-reported measures, including the Kansas City Cardiomyopathy Questionnaire (KCCQ) and the EuroQol Visual Analog Scale (VAS), and clinical measures, including peak VO(2), 6-minute walk distance, and New York Heart Association (NYHA) class, were assessed at baseline in 2331 patients with heart failure. We used general linear models to regress patient-reported measures on each clinical measure. Final models included for significant sociodemographic variables and 2-way interactions.

Results: The KCCQ was correlated with peak VO(2) (r = .21) and 6-minute walk distance (r = .27). The VAS was correlated with peak VO(2) (r = .09) and 6-minute walk distance (r = .11). Using the KCCQ as the response variable, a 1-SD difference in peak Vo(2) (4.7 mL/kg/min) was associated with a 2.86-point difference in the VAS (95% CI, 1.98-3.74) and a 4.75-point difference in the KCCQ (95% CI, 3.78-5.72). A 1-SD difference in 6-minute walk distance (105 m) was associated with a 2.78-point difference in the VAS (95% CI, 1.92-3.64) and a 5.92-point difference in the KCCQ (95% CI, 4.98-6.87); NYHA class III was associated with an 8.26-point lower VAS (95% CI, 6.59-9.93) and a 12.73-point lower KCCQ (95% CI, 10.92-14.53) than NYHA class II.

Conclusions: These data may inform deliberations about how to best measure benefits of heart failure interventions, and they generally support the practice of considering a 5-point difference on the KCCQ and a 3-point difference on the VAS to be clinically meaningful.

Trial registration: ClinicalTrials.gov NCT00047437.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Ambulatory Care* / standards
  • Attitude to Health
  • Exercise Test / statistics & numerical data
  • Exercise Tolerance
  • Female
  • Health Policy*
  • Health Status*
  • Heart Failure / diagnosis*
  • Heart Failure / physiopathology
  • Heart Failure / therapy*
  • Humans
  • Male
  • Managed Care Programs* / standards
  • Middle Aged
  • Outcome Assessment, Health Care / statistics & numerical data
  • Oxygen Consumption / physiology
  • Prognosis
  • Quality of Life
  • Surveys and Questionnaires
  • Ventricular Dysfunction, Left / diagnosis
  • Ventricular Dysfunction, Left / physiopathology
  • Ventricular Dysfunction, Left / therapy

Associated data

  • ClinicalTrials.gov/NCT00047437