Dyspnea descriptors developed in Brazil: application in obese patients and in patients with cardiorespiratory diseases.

Objective: To develop a set of descriptive terms applied to the sensation of dyspnea (dyspnea descriptors) for use in Brazil and to investigate the usefulness of these descriptors in four distinct clinical conditions that can be accompanied by dyspnea. Methods: We collected 111 dyspnea descriptors from 67 patients and 10 health professionals. These descriptors were analyzed and reduced to 15 based on their frequency of use, similarity of meaning, and potential pathophysiological value. Those 15 descriptors were applied in 50 asthma patients, 50 COPD patients, 30 patients with heart failure, and 50 patients with class II or III obesity. The three best descriptors, as selected by the patients, were studied by cluster analysis. Potential associations between the identified clusters and the four clinical conditions were also investigated. Results: The use of this set of descriptors led to a solution with seven clusters, designated sufoco (suffocating), aperto (tight), rapido (rapid), fadiga (fatigue), abafado (stuffy), trabalho/inspiracao (work/inhalation), and falta de ar (shortness of breath). Overlapping of descriptors was quite common among the patients, regardless of their clinical condition. Asthma was significantly associated with the sufoco and trabalho/inspiracao clusters, whereas COPD and heart failure were associated with the sufoco, trabalho/inspiracao, and falta de ar clusters. Obesity was associated only with the falta de ar cluster. Conclusions: In Brazil, patients who are accustomed to perceiving dyspnea employ various descriptors in order to describe the symptom, and these descriptors can be grouped into similar clusters. In our study sample, such clusters showed no usefulness in differentiating among the four clinical conditions evaluated.