Affective evaluation and cognitive structure of respiratory sensations in healthy individuals

Dyspnea is defined as an uncomfortable awareness of the need to breathe. Verbal report of dyspnea can be a valuable source of diagnostic information. However, little is known about the cognitive representation of respiratory sensations and about their affective evaluation in individuals not suffering from respiratory disease. Such knowledge would be important in evaluating the comparability of respiratory sensation report between healthy controls and patient groups.

Five hundred and eighty-two healthy individuals rated 20 descriptors of respiratory sensation with regard to frequency, valence, and situational incidence. Ratings were analysed on the level of subgroups of items found with cluster analysis and Multidimensional Scaling (MDS).

Not all respiratory sensations commonly subsumed under dyspnea are perceived to be uncomfortable by healthy individuals. Two higher-order clusters were found, interpreted as (1) compensation of dyspnea and (2) breathing deficiencies. Breathing deficiencies were unknown by approximately 50% of participants and rated to be less frequent and more uncomfortable than compensation of dyspnea. Furthermore, three dimensions of respiratory sensations were found using MDS interpreted as (1) fit between need for air and actual breathing, (2) effort, and (3) attempt of voluntary control.

The extent to which respiratory sensation ratings can be compared between patients and healthy individuals is limited. Latent dimensions of dyspnea might be less affected by differences in interpretation and evaluation of language descriptors of dyspnea and could help to assess comparability of sensation report between groups with different experiential background regarding breathlessness.