Objectives: This study examines the relationship between functional impairment and depression in patients with heart failure using a new measure of Attitudes about Impairment.
Methods: Sixty-nine patients with chronic heart failure completed diagnostic interviews and questionnaires about mood, comorbid illness, functional impairment, and social support. Study design was case-control with cases selected because they met criteria for DSM-IV major or minor depression (n = 23). Controls reported no or very few depressive symptoms (n = 46). A preliminary study of the psychometric properties of a new 15-item measure of Attitudes about Impairment was conducted.
Results: The Attitudes about Impairment measure had a Cronbach's alpha = 0.81. A factor analysis revealed content domains of negative attitudes about dependency, lack of recreational activities, and concerns about being a burden both currently and in the future. This measure correlated highly with the Geriatric Depression Scale (r = 0.61) and remained high even after controlling for medical burden and social support. Patients were diagnosed with either major, minor or no depression using a DSM-IV based structured interview. Depressed patients had significantly more negative attitudes about impairment and the association between depression and physical impairment was no longer significant after controlling for scores on the Attitudes about Impairment measure.
Discussion: Negative attitudes about loss of autonomy, concerns about being a burden and having few recreational activities are strongly associated with depression in patients with heart failure. These attitudes account, in part, for the association between impairment and depression in these patients. The Attitudes about Impairment measure has adequate internal consistency and both convergent and discriminant validity with related measures of social support, functional disability and depression.