Background: Although some studies evaluated venous thromboembolism (VTE) prevalence in patients with chronic obstructive pulmonary disease (COPD), they contain no detailed description of the patients' characteristics. Objectives: It was the aim of this study to investigate the frequency and clinical characteristics and outcomes of VTE in patients with COPD exacerbation. Methods: Between October 2004 and February 2005, 120 consecutive patients were included in the study. On admission, Doppler examination of lower extremities in all cases and spiral computed tomography of the thorax in cases with a suspicion of pulmonary thromboembolism were performed. A questionnaire was used to take a detailed history. In addition to routine laboratory tests, chest X-ray, postbronchodilator spirometry, arterial blood gas analysis and serum levels of D-dimer and C-reactive protein were evaluated, as well as dyspnea score and performance status before exacerbation. The hospitalization durations and mechanical ventilation requirements were also recorded. Results: VTE was determined in 16 cases (13.3%). In patients with VTE, the travel history was higher (p < 0.001), the dyspnea score worse (p = 0.005), the duration of hospitalization longer (p < 0.001) and the mechanical ventilation requirement increased (p < 0.001); a change in mental status was highly associated with the presence of VTE (p < 0.001). Conclusions: It seems that VTE occurrence was higher in the presence of a risk factor causing immobility such as travel history and increased dyspnea. The cases with severe disease are more likely to have VTE. Preventive measures may be considered in such patients because their hospitalization stay and mechanical ventilation requirement are increased. Copyright (C) 2006 S. Karger AG, Basel.