Development of a dyspnoea word cue set for studies of emotional processing in COPD.
Herigstad M., Hayen A., Reinecke A., Pattinson KT.
Patients with chronic dyspnoea may learn to fear situations that cue dyspnoea onset. Such dyspnoea-specific cues may then cause anxiety, and worsen or trigger dyspnoea even before commencement of physical activity. We therefore developed an experimental tool to probe emotional processing of dyspnoea for use with neuroimaging in COPD. The tool consists of a computerised task comprising multiple presentations of dyspnoea-related word cues with subsequent rating of dyspnoea and dyspnoea-anxiety with a visual analogue scale. Following 3 development stages, sensitivity to clinical change was tested in 34 COPD patients undergoing pulmonary rehabilitation. We measured internal consistency, sensitivity to clinical change and convergence with established dyspnoea measures (including Dyspnoea-12). Cronbach's alpha was 0.90 for dyspnoea and 0.94 for anxiety ratings. Ratings correlated with Dyspnoea-12 (dyspnoea: r=0.51, P=0.002; anxiety: r=0.54, P=0.001). Reductions in anxiety ratings following pulmonary rehabilitation correlated with reductions in Dyspnoea-12 (r=0.51, P=0.002). We conclude that the word-cue task is reliable, and is thus a potentially useful tool for neuroimaging dyspnoea research.