Dyspnea perception in COPD: association between anxiety, dyspnea-related fear, and dyspnea in a pulmonary rehabilitation program.

Background A growing body of research connects anxiety with poorer outcomes in COPD. However, more specific measures of dyspnea-related fear may be more closely related to critical processes involved in pulmonary rehabilitation (perception of dyspnea and avoidance of physical activity) and may have a predictive value for COPD outcome beyond general anxiety measures. Methods In this naturalistic outcome study, we investigated the effects of baseline anxiety and dyspnea-related fear on perceived dyspnea and other outcomes of a well-established pulmonary rehabilitation program for COPD. Results Seventy-three patients participated in the study. At baseline, higher dyspnea-related fear was associated with higher levels of dyspnea during ergometer exercise, but also with a steeper decrease of exercise dyspnea during the course of pulmonary rehabilitation, whereas lower dyspnea-related fear was associated with an increase in exercise dyspnea, even when controlling for anxiety, lung function, and exercise intensity. Furthermore, higher dyspnea-related fear was associated with reduced quality of life (mastery subscale) and maximal exercise capacity at baseline, but also with a steeper increase in quality of life (emotions and mastery subscale) and exercise capacity during rehabilitation. However, the association of dyspnea-related fear with worse 6-min walking distance and impairment in daily activities persisted throughout rehabilitation. Conclusions Results indicate a mediating effect of dyspnea-related fear on the association between anxiety and exercise-related dyspnea. Exercise in pulmonary rehabilitation in people with higher baseline dyspnea-related fear may act as a correction of excessive symptom reports through exposure to dyspneic situations.