Can health status questionnaires be used as a measure of physical activity in COPD patients

Acting to address the amount of physical activity of patients with chronic obstructive pulmonary disease (COPD) is recommended as part of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommendations [1]. A level lower than approximately 5000 steps for day (sedentary lifestyle index) is associated with significantly increased health risks [2, 3]. Actively screening to identify patients below this threshold could be an important step towards targeting interventions to increase physical activity. Potential screening tools include activity monitors (objective assessment) or self-reported questionnaires (subjective assessment) to measure the amount of physical activity [4]. The latter method, which is feasible in clinical practice, may not result in an accurate representation in an individual patient, as questionnaire responses tend to misclassify physical activity [5]. Although more accurate and widely used in research, activity monitoring is not yet commonly included in patients' routine assessment. Several health status questionnaires in routine clinical use contain a domain or dimension related to physical activity [6]. In the analytical framework of Leidy [7], functional performance has been defined as the physical, psychological, social, occupational and spiritual activities that people actually do in the normal course of their lives to meet basic needs, fulfil usual roles, and maintain their health and wellbeing. A review by Kocks et al . [8] proposed that these questionnaires could be used in the measurement of functional performance (defined as “what a patient is actually doing”) and that this would be a more practical alternative to physical activity monitoring. Whether this approach is sufficiently valid as a representation of physical activity levels in clinical practice remains to be established. Health status questionnaires provide only limited insight into the physical activity of patients with COPD The PROactive Consortium members are as follows. Nathalie Ivanoff: Almirall, Barcelona, Spain; Niklas Karlsson and Solange Corriol-Rohou: AstraZeneca AB, Molndal, Sweden; Ian Jarrod: British Lung Foundation, London, UK; Damijen Erzen: Boehringer Ingelheim, Nieder-Ingelheim, Germany; Mario Scuri and Roberta Montacchini: Chiesi Farmaceutici S.A. Parma, Italy; Paul McBride: Choice Healthcare Solutions, Hitchin, UK; Nadia Kamel: European Respiratory Society, Lausanne, Switzerland; Margaret Tabberer: GlaxoSmithKline, Uxbridge, UK; Thierry Troosters, Wim Janssens and Fabienne Dobbels,: Katholieke Universiteit Leuven, Leuven, Belgium; Judith Garcia-Aymerich, Municipal Institute of Medical Research, Barcelona, Spain; Pim de Boer: Netherlands Lung Foundation, Amersfoort, The Netherlands; Karoly Kulich and Alastair Glendenning: Novartis, Basel, Switzerland; Michael I. Polkey and Nick S. Hopkinson: Royal Brompton and Harefield NHS Foundation Trust, London, UK; Ioannis Vogiatzis: Thorax Research Foundation, Athens, Greece; Enkeleida Nikai: UCB, Brussels, Belgium; Thys van der Molen and Corina De Jong: University Medical Center, Groningen, The Netherlands; Roberto A. Rabinovich and Bill MacNee: University of Edinburgh, Edinburgh, UK; Milo A. Puhan and Anja Frei: University of Zurich, Zurich, Switzerland.