Discriminant Validity of a Single Clinical Question for the Screening of Inactivity in Individuals Living with COPD

Abstract

Maria Antonia Ramon,1 Cristóbal Esteban,2 Francisco Ortega,3 Pilar Cebollero,4 Inés Carrascosa,5 Cristina Martinez-González,6 Patricia Sobradillo,7 Juan José Soler-Cataluña,8 Marc Miravitlles,9 Francisco García-Río10 1Pneumology Department, Hospital Universitari Vall d´Hebron/Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus; Physical Therapy Department, Universitat Internacional de Catalunya and CIBER de Enfermedades Respiratorias (CIBERES), Barcelona, Spain; 2Respiratory Department, Hospital Galdakao; Health Services Research on Chronic Patients Network (REDISSEC) and BioCrues-Bizkaia Health Research Institute, Baracaldo, Spain; 3Pneumology Department, Hospital Universitario Virgen del Rocío; Instituto de Biomedicina de Sevilla (IBiS), and CIBER de Enfermedades Respiratorias (CIBERES), Sevilla, Spain; 4Pneumology Department, Hospital CH de Navarra, Pamplona, Spain; 5Pneumology Department, Hospital Urduliz, Urduliz, Bizkaia, Spain; 6Pneumology Department, Hospital Universitario Central de Asturias, Oviedo, Spain; 7Pneumology Department, Hospital de Cruces, Bilbao, Spain; 8Pneumology Department, Hospital Arnau de Vilanova-Lliria, Valencia, Spain; 9Pneumology Department, Hospital Universitari Vall d´Hebron/Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Barcelona Hospital Campus and CIBER de Enfermedades Respiratorias (CIBERES), Barcelona, Spain; 10Pneumology Department, Hospital Universitario La Paz-IdiPAZ, and CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, SpainCorrespondence: Marc Miravitlles, Pneumology Department, Hospital Universitari Vall d´Hebron/Vall d’Hebron Institut de Recerca (VHIR), Vall d´Hebron Barcelona Hospital Campus, P. Vall d’Hebron 119-129, Barcelona, 08035, Spain, Tel [phone], Fax [phone], Email [email protected]: Quantifying physical activity in chronic obstructive pulmonary disease (COPD) with questionnaires and activity monitors in clinical practice is challenging. The aim of the present study was to analyse the discriminant validity of a single clinical question for the screening of inactive individuals living with COPD.Methods: A multicentre study was carried out in stable COPD individuals both in primary and tertiary care. Patients wore the Dynaport accelerometer for 8 days and then answered 5 physical activity questions developed for the study, referring to the week in which their physical activity was monitored. Receiver operating characteristic (ROC) curve analysis with physical activity level (PAL) as the gold standard reference was used to determine the best cut-off point for each of the 5 clinical physical activity questions tested.Results: A total of 86 COPD participants were analysed (males 68.6%; mean (SD) age 66.6 (8.5) years; FEV1 50.9 (17.3)% predicted; mean of 7305 (3906) steps/day). Forty-two (48.8%) participants were considered physically inactive (PAL ≤ 1.69). Answers to 4 out of 5 questions significantly differed in active vs inactive patients. The Kappa index and ROC curves showed that the answer to the question “On average, how many minutes per day do you walk briskly?” had the best discriminative capacity for inactivity, with an area under the curve (AUC) (95% Confidence interval (CI)) of 0.73 (0.63– 0.84) and 30 min/day was identified as the best cut-off value (sensitivity (95% CI): 0.75 (0.60– 0.87); specificity: 0.76 (0.61– 0.88)).Conclusion: The present results indicate that self-reported brisk walk time lower than 30 min/day may be a valid tool for the screening of inactivity in individuals living with COPD in routine care, if more detailed physical activity measures are not feasible.Keywords: chronic obstructive pulmonary disease, physical activity, outcome assessment, validation studies

Keywords

• chronic obstructive pulmonary disease
• physical activity
• outcome assessment
• validation studies.