Defining Chronic Mucus Hypersecretion Using the CAT in the SPIROMICS Cohort

Abstract

Marni Stott-Miller,1 Hana Müllerová,2 Bruce Miller,3 Maggie Tabberer,4 Céline El Baou,5 Tom Keeley,4 Fernando J Martinez,6 Meilan Han,7 Mark Dransfield,8 Nadia N Hansel,9 Christopher B Cooper,10 Prescott Woodruff,11 Victor E Ortega,12 Alejandro P Comellas,13 Robert Paine III,14 Richard E Kanner,14 Wayne Anderson,15 M Bradley Drummond,15 Victor Kim,16 Ruth Tal-Singer,17 Aili L Lazaar3 1GSK R&D, Epidemiology: Value, Evidence and Outcomes, Uxbridge, UK; 2AstraZeneca, Cambridge, UK; 3GSK R&D, Discovery Medicine, Collegeville, PA, USA; 4GSK R&D Patient-Centred Outcomes: Value, Evidence and Outcomes, Uxbridge, UK; 5CEBSTAT Consultancy Ltd, London, UK; 6Cornell Medical College, New York, NY, USA; 7Division of Pulmonary and Critical Care at the University of Michigan, Ann Arbor, MI, USA; 8Children’s of Alabama, Children’s Health Research Unit/University of Alabama, Birmingham, AB, USA; 9Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA; 10David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; 11UCSF Department of Medicine, San Francisco, CA, USA; 12Wake Forest School of Medicine, Winston Salem, NC, USA; 13Carver College of Medicine, University of Iowa, Iowa City, IA, USA; 14Division of Pulmonary and Critical Care Medicine, University of Utah, Salt Lake City, UT, USA; 15Division of Pulmonary Diseases and Critical Care Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; 16Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA; 17COPD Foundation, Washington, DC, USACorrespondence: Aili L Lazaar GSK, 1250 S. Collegeville Road, Collegeville, PA 19426-0989, USATel [phone]Email [email protected]: Chronic cough and phlegm are frequently reported chronic obstructive pulmonary disease (COPD) symptoms. Prior research classified chronic mucus hypersecretion (CMH) based on the presence of these symptoms for ≥ 3 months, called chronic bronchitis (CB) if respiratory infection symptoms were present for 1– 2 years (Medical Research Council [MRC] definition). We explored whether the COPD Assessment Test (CAT), a simple measure developed for routine clinical use, captures CMH populations and outcomes similarly to MRC and St. George’s Respiratory Questionnaire (SGRQ) definitions.Methods: We identified CMH in the SPIROMICS COPD cohort using (a) MRC definitions, (b) SGRQ questions for cough and phlegm (both as most/several days a week), and (c) CAT cough and phlegm questions. We determined optimal cut-points for CAT items and described exacerbation frequencies for different CMH definitions. Moderate exacerbations required a new prescription for antibiotics/oral corticosteroids or emergency department visit; severe exacerbations required hospitalization. Results were stratified by smoking status.Results: In a population of 1431 participants (57% male; mean FEV1% predicted 61%), 47% and 49% of evaluable participants had SGRQ- or CAT-defined CMH, respectively. A cut-point of ≥ 2 for cough and phlegm items defined CMH in CAT. Among SGRQ-CMH+ participants, 80% were also defined as CMH+ by the CAT. CMH+ participants were more likely to be current smokers. A higher exacerbation frequency was observed for presence of CMH+ versus CMH− in the year prior to baseline for all CMH definitions; this trend continued across 3 years of follow-up, regardless of smoking status.Conclusion: Items from the CAT identified SGRQ-defined CMH, a frequent COPD trait that correlated with exacerbation frequency. The CAT is a short, simple questionnaire and a potentially valuable tool for telemedicine or real-world trials. CAT-based CMH is a novel approach for identifying clinically important characteristics in COPD that can be ascertained in these settings.Keywords: COPD, SGRQ, exacerbation, CAT, cough, phlegm

Keywords

• copd
• sgrq
• exacerbation
• cat
• cough
• phlegm