Assessment of Risk in Chronic Airways Disease Evaluation (ARCADE): Protocol and preliminary data.

Chronic obstructive pulmonary disease (COPD) is a multisystem disease. Established comorbidities include cardiovascular disease, osteoporosis, loss of muscle mass and function, depression, and impaired quality of life. The natural history is not well understood. The Assessment of Risk in Chronic Airways Disease Evaluation (ARCADE) is a longitudinal study of comorbidities in COPD. The primary aims are to delineate the progression and interrelationships of cardiovascular disease and associated comorbidities. Each year ARCADE aims to recruit 250 patients diagnosed with COPD and 50 comparators (free from respiratory disease). Assessments include spirometry, body composition, blood pressure, aortic stiffness (pulse wave velocity (PWV)), noninvasive measures of cardiac output, systemic inflammatory mediators, blood and urine biochemistry, and physical and health outcomes. These will be repeated at 2 and 5 years. In the first year of recruitment, 350 patients and 100 comparators were recruited. The reproducibility of aortic PWV, cardiac output, stroke volume, and cardiac index was evaluated and accepted in 30 patients free from overt cardiovascular disease. The preliminary data from ARCADE have demonstrated acceptable reproducibility of hemodynamic outcome measures. Further longitudinal data collection will increase knowledge of the progression and interactions between cardiovascular risk factors and other comorbidities in COPD.