Cognitive biases in patients with chronic obstructive pulmonary disease and depression--a pilot study

OBJECTIVES: Comorbid depression is highly prevalent in patients with chronic obstructive pulmonary disease (COPD) and associated with a worse course of disease; however, the exact mechanisms linking both remain unclear. In currently depressed individuals without lung disease, depression-specific biases in information processing have been suggested as risk factors for the development and maintenance of depression. We examined whether comparable biases in cognitive information processing might underlie depression in COPD.

DESIGN: Different aspects of cognitive information processing were examined with computer-based tasks measuring selective attention and memory in patients with COPD who were compared with age-matched, currently depressed patients without lung disease and healthy control participants.

METHODS: The Self-Referential Encoding and Incidental Recall Task as well as the emotion face dot-probe task was applied to 21 never-depressed COPD patients, 18 currently depressed COPD patients, 20 currently depressed patients without lung disease and 19 healthy controls to examine cognitive biases.

RESULTS: In both patients with COPD who were never and who were currently depressed, depression-like cognitive biases were observed for some attention- and memory-related tasks, but not for all tested aspects of information processing. These biases were particularly prominent in patients with COPD and current depression and comparable to those observed in currently depressed patients without lung disease.

CONCLUSIONS: The results of this pilot study suggest that patients with COPD may potentially show depression-like biases in some aspects of cognitive information processing. Future studies are required to examine whether these biases represent a vulnerability factor for the development of depression in patients with COPD.