Chronic Respiratory Questionnaire as a Predictor of Exercise Participation in Individuals with COPD

Abstract

The Chronic Respiratory Questionnaire (CRQ) is a well-established and a widely used measure of health-related quality of life (HRQL) for individuals with pulmonary diseases including Chronic Obstructive Pulmonary Disease (COPD). Although regular exercise participation has been shown to improve CRQ scores in COPD patients, relatively little is known about the relationship between CRQ scores and exercise related behavior including outcomes such as attendance and volume of exercise. PURPOSE: To examine the relationship of CRQ scores to both attendance at scheduled center-based visits (exercise adherence) and to the average distances walked (volume of exercise) during training in individuals with COPD while statistically controlling for age, number of comorbidities, and pulmonary function. METHODS: Seventy-four participants (age = 67.0 ± 9.9 years; height = 1.72 ±0.09m; weight = 83.4 ± 22.5 kg) with COPD completed the CRQ (mean total score = 13.9 ± 3.4) and a pulmonary function test to determine their forced expiratory volume in one second (FEV1) as a percentage of predicted values (52.8 ± 18.8%). Participants then started an exercise program where they were expected to complete a total of 36 exercise sessions over a 3-month period with walking as the primary aerobic activity. Participants were asked to record the distance they walked during each exercise session. RESULTS: Regression analyses and partial correlations were performed while controlling for age, number of comorbidities, and FEV1. Total CRQ scores were found to be positively correlated, r = 0.261, p = 0.03 with adherence of the participants to the exercise program. Total CRQ scores were also found to be positively correlated, r = 0.442, p <0.01 with the volume of exercise performed by the participants during the exercise sessions. CONCLUSION: Total score of the CRQ significantly and independently predicts exercise adherence and the volume of exercise performed by individuals with COPD in a 3-month training program. Individuals with higher CRQ scores were more adherent to exercise training and performed higher volumes of exercise than those with lower scores. These results underscore the role of psychological factors in understanding exercise behavior of individuals with COPD. Supported by NIH Grants HL 53755 and AG 10484