Acute Exacerbation and Respiratory InfectionS in COPD (AERIS): protocol for a prospective, observational cohort study

Bourne, Simon; Cohet, Catherine; Kim, Viktoriya; Barton, Anna; Tuck, Andy; Aris, Emmanuel; Mesia-Vela, Sonia; Devaster, Jeanne-Marie; Ballou, W Ripley; Clarke, Stuart; Wilkinson, Tom

• Cohort retention is a key factor in the successful delivery of such a study and with in-depth sampling protocols, participant engagement, comfort and feedback are key factors in optimising cohort retention and comprehensive data collection. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 Considerable progress has been made concerning the epidemiology, pathophysiology and clinical management of COPD in recent years. However, significant challenges remain. Improved understanding of acute exacerbations of COPD (AECOPD) is a key research priority. AECOPD are highly relevant clinically, being a major cause of COPD-related morbidity and mortality, 7-11 as well as accounting for a substantial proportion of the significant social, healthcare and economic burden of COPD. 6 It has been estimated that AECOPD account for approximately 70% of total healthcare costs associated with COPD. 12 Patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage II or more disease experience 1 or 2 exacerbations annually. Exacerbation varies from patient to patient with severity of disease. 13 Various triggers for AECOPD have been identified; 1 however, up to 75% of all exacerbations are associated with the detection of bacterial and/or viral respiratory pathogens. 14, 15 Exacerbations associated with detectable respiratory pathogens have been shown to have a more marked impact on