Measurement of health-related quality of life in heart failure

Abstract

Measurement of health-related quality of life is becoming increasingly relevant to controlled clinical trials. Two basic approaches to health-related quality of life measurement are available: generic instruments which attempt to provide a summary of health-related quality of life; and specific instruments which focus on problems associated with individual disease states, patient groups, or areas of function. Generic instruments include health profiles and instruments which generate health utilities. The approaches are not mutually exclusive. Each approach has its strengths and weaknesses and may be suitable under different circumstances.

Investigators have developed a number of disease-specific measures for heart failure. For each measure there is some evidence regarding key measurement properties, responsiveness and validity. An instrument is responsiveness if it can detect important changes, even if those changes are small. An instrument is valid if it is really measuring what it is supposed to measure. Only one disease-specific instrument which addresses a wide range of health-related quality of life impairment, the Minnesota Living with Heart Failure Questionnaire, has shown responsiveness in the context of double-blind, multi-centre pharmaceutical clinical trials.

Both generic and specific measures should find increasing use in clinical trials in heart failure. Careful attention to rigorous administration is necessary for useful results. Investigators should construct trials to obtain additional data regarding both validity and changes in instrument score which correspond to small, medium, and large changes in health-related quality of life. If these guidelines are followed useful information about the impact of interventions in heart failure will become increasingly available.