Attributions about cause of illness in chronic obstructive pulmonary disease

Objective: Patients' beliefs about the causes of their illness have been associated with emotional adjustment and behavioral outcomes in several medical conditions; however, few studies have examined illness attributions among patients with chronic obstructive pulmonary disease (COPD). In the current study, patterns of patients' causal attributions for COPD were identified and examined in relation to health behaviors and symptoms.

Method: Three-hundred and ninety-four patients with COPD and >10 pack year history of smoking completed a self-report questionnaire that included the Illness Perception Questionnaire-Revised (IPQ-R).

Results: A factor analysis of the IPQ-R cause items using principal axis factoring yielded four individual items (i.e., smoking, heredity, pollution, and personal behavior) and one large factor that was primarily driven by psychological attributions. Ninety-three percent of patients agreed or strongly agreed that smoking was a cause of their COPD. Higher scores on the large IPQ-R factor were associated with reduced quality of life (r=.25, P<.001) and symptoms of anxiety (r=.33, P<.001) and depression (r=.31, P<.001), indicating that patients who attributed their COPD to psychological factors were more likely to have poorer emotional adjustment and quality of life.

Conclusions: Our finding of one large factor with several stand-alone items is in contrast with previous research that has derived a multifactor structure for the cause items of the IPQ-R in other chronic illness populations. This difference may be due to the importance of smoking, environmental exposures, and heredity in the development of COPD. Future research should expand upon these specific attributions in COPD.