PT  - JOURNAL ARTICLE
AU  - Russell Bowler
AU  - Matthew Allinder
AU  - Sean Jacobson
AU  - Andrew Miller
AU  - Bruce Miller
AU  - Ruth Tal-Singer
AU  - Nicholas Locantore
TI  - Real-world use of rescue inhaler sensors, electronic symptom questionnaires and physical activity monitors in COPD
AID  - 10.1136/bmjresp-2018-000350
DP  - 2019 Feb 01
TA  - BMJ Open Respiratory Research
PG  - e000350
VI  - 6
IP  - 1
4099  - http://bmjopenrespres.bmj.com/content/6/1/e000350.short
4100  - http://bmjopenrespres.bmj.com/content/6/1/e000350.full
SO  - BMJ Open Resp Res2019 Feb 01; 6
AB  - Background Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterised by airflow obstruction and other morbidities such as respiratory symptoms, reduced physical activity and frequent bronchodilator use. Recent advances in personal digital monitoring devices can permit continuous collection of these data in COPD patients, but the relationships among them are not well understood.Methods 184 individuals from a single centre of the COPDGene cohort agreed to participate in this 3-week observational study. Each participant used a smartphone to complete a daily symptom diary (EXAcerbations of Chronic pulmonary disease Tool, EXACT), wore a wrist-worn accelerometer to record continuously physical activity and completed the Clinical Visit PROactive Physical Activity in COPD questionnaire. 58 users of metered dose inhalers for rescue (albuterol) were provided with an inhaler sensor, which time stamped each inhaler actuation.Results Rescue inhaler use was strongly correlated with E-RS:COPD score, while step counts were correlated with neither rescue use nor E-RS:COPD score. Frequent, unpatterned inhaler use pattern was associated with worse respiratory symptoms and less physical activity compared with frequent inhaler use with a regular daily pattern. There was a strong week-by-week correlation among measurements, suggesting that 1 week of monitoring is sufficient to characterise stable patients with COPD.Discussion The study highlights the interaction and relevance of personal real-time monitoring of respiratory symptoms, physical activity and rescue medication in patients with COPD. Additionally, visual displays of longitudinal data may be helpful for disease management to help drive conversations between patients and caregivers and for risk-based monitoring in clinical trials.