The impact of disease-specific fear on the neural processing of respiratory sensations and physical activity in COPD

Recent studies show that in COPD patients disease-specific fears (DSF) are related to increased dyspnea perception and worse disease outcomes. However, little is known about the neural mechanisms underlying the perception of respiratory sensations in COPD patients, and especially about its interactions with DSF. Furthermore, physical activity (PA) plays an important role in COPD disease progression but respective associations with DSF and neural processes are unknown. Therefore, we examined the associations between DSF, the perception and neural processing of respiratory sensations, and PA in daily life in COPD patients. In 33 patients (FEV1%pred=49), respiratory-related evoked potentials (RREPs) were elicited by short inspiratory occlusions and measured with 128-channel EEG. DSF was assessed with the Somatic Focus (dyspnea-related fear) and Activity Avoidance (activity-related fear) subscales of the Breathlessness Beliefs Questionnaire (BBQ). PA was assessed with accelerometers (Actigraph GT3x). Regression analysis showed that more dyspnea-related fear was associated with higher perception of occlusions and higher amplitudes of RREP component P2. Dyspnea- and activity-related fear were also associated with lower PA (p’s<0.05). Notably, higher amplitudes of RREP component P2 were further associated with lower PA (p<0.01). Our findings firstly show that higher levels of dyspnea-related fears in COPD patients are related to increased perception and neural processing of respiratory sensations as well as to lower levels of PA, suggesting a mediating role of greater neural processing to underlie the relation between higher dyspnea-related fears and lower PA in COPD.