Objective: To determine the direction and rate of change in the symptom of dyspnea in patients with chronic obstructive pulmonary disease (COPD) whose lung function has worsened over time.
Design: Secondary analysis of a longitudinal data set.
Setting: Outpatient clinic.
Patients: Thirty-four medically stable male subjects with chronic obstructive pulmonary disease studied for 5.3 +/- 3.5 years, with a mean reduction in FEV1 over the period studied of 330.9 +/- 288.0 mL. Subjects were 63.3 +/- 5.5 years of age at entry into the study.
Outcome measures: Dyspnea and functional status scores were obtained using the Pulmonary Functional Status and Dyspnea Questionnaire.
Results: There was no significant difference in reports of dyspnea from the beginning to the end of the study, despite significant reductions in lung function. Of all activities studied, dyspnea when raising arms overhead was the only activity showing a relationship to the slope of change in FEV1 %.
Conclusion: These findings suggest that, although patients with chronic lung disease experience varying degrees of deterioration in lung function longitudinally, there is no evidence that they report worsening of dyspnea in tandem with these physiologic changes. In this study, patient ratings of dyspnea longitudinally were not directly linked to changes in lung impairment.