Clinical and Physiological Effects of Exercise Training in Dyspneic Mild COPD Patients: Design of the Study
Gonzalo Labarca
Faculty of Medicine, Universidad San Sebastián, Concepción, Chile and Division of Internal Medicine, Complejo Asistencial Dr. Víctor Ríos Ruiz, Los Ángeles, Chile.
Andrea Bustamante
Department of Pulmonary Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile.
Francisco Rodríguez
Department of Kinesiology, Pontifical Catholic University of Chile, Health Network, Santiago, Chile.
Igor Nuñez
Department of Kinesiology, Pontifical Catholic University of Chile, Health Network, Santiago, Chile.
Gonzalo Valdivia
Department of Public Health, Faculty of Medicine, Pontifical Catholic University of Chile, Chile.
Paul Mac Nab
Department of Cardiovascular Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Chile.
Álvaro Huete
Department of Radiology, Faculty of Medicine, Pontifical Catholic University of Chile, Chile.
Jaime Leppe
School of Kinesiology, Faculty of Medicine, Clínica Alemana, Universidad del Desarrollo, Chile.
Fernando Saldías
Department of Pulmonary Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile.
Orlando Díaz *
Department of Pulmonary Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile and Department of Critical Care, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile.
*Author to whom correspondence should be addressed.
Abstract
Introduction: Mild chronic obstructive pulmonary disease (COPD) may be associated with physical inactivity, exercise limitation, and impaired health related quality of life, because of a combination of deconditioning, dyspnea, and reduced peripheral muscle mass. Although the benefits of exercise training (ET) in counteracting these consequences are well established in moderate-to-very-severe COPD, it is unclear if they are also effective in mild disease. The aim of this paper is to describe the design of a randomized controlled trial (RCT) to assess the efficacy of ET in patients with mild COPD and dyspnea, defined by a modified Medical Research Council dyspnea score ≥1. We hypothesize that their effectiveness will be similar to that observed in more advanced disease because of the presence of breathlessness. Consequently, ET will improve exercise limitation and health-related quality of life (HRQoL) in dyspneic mild COPD patients in comparison to usual care.
Methods and Analysis: In this RCT, 60 mild dyspneic COPD patients (post-bronchodilator forced expiratory volume in 1 s [FEV1] ≥80% of predicted value and post-bronchodilator FEV1/ forced vital capacity [FVC] ≤70%) will be randomized to an intervention or usual care group. The intervention group will receive a 2-month ET program, which will include cycle exercise and muscle resistance training, whereas the control group will receive usual care. Primary outcome will be the change on the six-min walk test after ET. Secondary outcomes will include changes in HRQoL, assessed with the St. George’s Respiratory Questionnaire, and changes in exercise time during a constant load cycle exercise.
Discussion: This will be the first RCT evaluating the efficacy of an ET program in patients with mild COPD. These results could be of relevance to clinical practice and develop new recommendation in mild disease.
Keywords: COPD, dyspnea, pulmonary rehabilitation