Objectives: To identify clusters of chronic obstructive pulmonary disease (COPD) patients with distinct beliefs about their illness in terms of symptoms, health-related quality of life (HRQoL), self-efficacy, and daily life physical activity (DLPA).
Methods: This cross-sectional study included 150 COPD outpatients. The patients' illness perceptions, clinical control, HRQoL, self-efficacy, and DLPA (accelerometry) were evaluated. A cluster analysis was conducted using data from the Illness Perceptions Questionnaire - Revised to establish groups of patients with distinct illness perceptions. Differences between clusters were tested using a T-test or a Mann-Whitney U test.
Results: The cluster analysis revealed two groups: distressed ( n = 95) and coping ( n = 55). Despite the fact that both clusters presented similar pulmonary function, between-cluster differences were observed in their self-efficacy, dyspnea, HRQoL, clinical control ( p < 0.001), and educational level ( p = 0.002). The levels of DLPA did not differ between the clusters.
Discussion: We observed that clinically stable COPD patients who displayed higher emotional representations and less coherence had heightened symptoms, poorer HRQoL, worse self-efficacy, and lower educational levels. These results emphasize the need to routinely evaluate illness perceptions in COPD patients to target and tailor the proper treatment to improve these important health outcomes.
Keywords: Chronic obstructive pulmonary disease; dyspnea; health-related quality of life; illness perceptions; self-efficacy.