Evaluation of impairment of health related quality of life in asthma: development of a questionnaire for use in clinical trials.

TLDR

Asthma interventions have historically been assessed only by physiological and clinical outcomes, leaving the effect on patients’ lives largely unexamined. This study sought to evaluate health‑related quality‑of‑life impairment in adult asthmatics and to develop a questionnaire for measuring that impairment in clinical trials. The authors interviewed 150 adults with asthma to identify daily life impacts, then created a 32‑item questionnaire in interviewer and self‑administered formats and pretested it for comprehension and acceptability. The questionnaire captured symptoms, environmental triggers, activity limitations, and emotional dysfunction, was consistent across airway hyperresponsiveness, age, treatment, and sex, and was acceptable to patients, making it a responsive outcome measure for asthma trials.

Abstract

BACKGROUND: In the past only physiological and clinical outcomes have been used to assess the effect of asthma interventions and the effect of the intervention on the lives of the patients has not been determined. The objective of this study was to assess health related impairment of quality of life in adult asthmatic patients and to develop a questionnaire for measuring quality of life in clinical trials in asthma. METHODS: Impairment of quality of life in adults with asthma was evaluated from structured interviews in which patients were asked to identify the parts of their daily lives affected by asthma. On the basis of these results, an asthma quality of life questionnaire was developed in an interviewer and self administered form and tested for comprehension and acceptability. A total of 150 adults with asthma and with a wide range of airway hyperresponsiveness were enrolled from previous clinical trials, local asthma clinics, and notices in the media. RESULTS: Areas of quality of life impairment included symptoms classically associated with asthma, responses to environmental stimuli, the need to avoid these stimuli, limitation of activities, and emotional dysfunction. Areas of impairment were similar across strata of airway hyperresponsiveness, age, and treatment requirements and between sexes, thus allowing a single questionnaire suitable for all adults with asthma to be developed. The questionnaire contains 32 items and takes 5-10 minutes to administer; in the pretesting it was shown to be acceptable to a wide range of patients. CONCLUSIONS: The questionnaire includes areas of quality of life impairment that are important to adult asthmatic patients. It has been designed to be responsive to within subject change and therefore may be used as a measure of outcome in clinical trials in asthma.