['To investigate the relationship between the presence of symptoms of anxiety or depression with breathing pattern and thoracoabdominal mechanics at rest and during exercise in COPD.', 'Cross-sectional study enrolled 54 patients with COPD ranked according to Hospital Anxiety and Depression Scale (HAD) score and compared to dyspnea, clinical control, hypercapnia, breathing pattern and thoracoabdominal mechanics at rest and during exercise.', 'Seventeen patients with COPD had no symptoms, 12 had anxiety symptoms, 13 had depressive symptoms and 12 had both symptoms. COPD with depressive symptoms presented greater degree of dyspnea (p<0.01). Poor clinical control was observed in COPD with anxious and/or depressive symptoms (p<0.05). Breathing pattern and thoracoabdominal mechanics were similar among all groups at rest and during exercise.'] Are anxiety and depression related to dyspnea and clinical control but not with thoracoabdominal mechanics in patients with COPD?