BACKGROUND: Verbal descriptors of
dyspnea are important in understanding the underlying mechanisms, but little is known about the language of
dyspnea in
COPD. We examined the language of
dyspnea in
COPD at different
intensity levels of
dyspnea. METHODS: Verbal descriptors of
dyspnea were assessed in 64 patients with moderate-to-severe
COPD (
mean age, 62 years;
mean percentage of predicted FEV(1) [FEV(1)%pred], 54.1%) during slight
dyspnea at rest (
mean Borg score, 1.8), moderate
dyspnea during cycle ergometer exercise (
mean Borg score, 3.1) and somewhat severe
dyspnea during a 6-min walking test before (
mean Borg score, 4.2), and after
pulmonary rehabilitation (PR) [
mean Borg score, 3.5]. Furthermore, the influence of age, gender, baseline
lung function (FEV(1)%pred), and PR on the verbal descriptors were studied. RESULTS: A
cluster analysis showed that patients differentiated between five clusters of verbal descriptors of
dyspnea: heavy/
fast breathing,
shallow breathing, obstruction, work/effort, and
suffocation. These were related to the
intensity level of
dyspnea but not to age, gender, baseline
lung function, or PR. While
shallow breathing was predominant only during slight
dyspnea at rest, heavy/
fast breathing and to a lesser extent work/effort became more important during moderate and somewhat severe
dyspnea during exercise. The clusters heavy/
fast breathing and work/effort demonstrated the highest sensitivity in discriminating between different
intensity levels of
dyspnea and in characterizing the positive effects of PR. CONCLUSIONS: Verbal descriptors of
dyspnea in
COPD are related to the
intensity level of
dyspnea. The clusters heavy/
fast breathing and work/effort seem to be particularly sensitive descriptors of
dyspnea during exercise in
COPD.
