FEV1 and pulmonary rehabilitation: Let's get the facts straight.

Abstract

Pulmonary rehabilitation (PR) is a miracle intervention. Despite the lack of effect on resting lung function,1 symptomatic people with chronic obstructive pulmonary disease (COPD) generally have less symptoms (i.e., dyspnea, fatigue, anxiety and depression), better physical functioning and physiological exercise responses, less care dependency, an improved performance of activities of daily life, less healthcare use and an improved quality of life following a 8–12 weeks multidisciplinary PR program on top of the regular respiratory drug treatment.2-10 To date, post-bronchodilator forced expiratory volume in the first second (FEV1) is still often used as a selection criterion for referral for PR.11, 12 However, FEV1 is useless for this objective. Let us get the facts straight: Fact 1: Baseline FEV1 does not or only weakly correlate with physical, emotional and social functioning of people with COPD. Daily symptoms (such as dyspnea, fatigue, anxiety and depression), abnormal body composition, low exercise capacity, problematic activities of daily life, low physical activity and an impaired health status can occur in people with COPD, irrespective of the degree of airflow limitation.13-18 Moreover, FEV1 is only weakly correlated with the number of extra-pulmonary traits.18 So, FEV1 cannot be used to identify symptomatic people with limitations in daily functioning and extra-pulmonary traits, which can be addressed during a comprehensive PR program.2 Fact 2: Baseline FEV1 does not predict the likelihood of dropping out. PR programs report that 15%–40% of the participants drop out from the program.5, 19-25 Generally, people with COPD who drop out have similar baseline FEV1 compared to those who complete the PR program.19-22, 24 The presence of psychological factors (i.e., depressive symptoms, lack of motivation and/or distress arising from bodily perceptions), social factors (i.e., transportation difficulties, other duties or responsibilities, unsupportive remarks by staff or patients and/or conflict with other patients) and/or people's perception of insufficient improvements during the PR program, may partially explain why people with COPD drop out, irrespective of baseline FEV1.24, 26 So, baseline FEV1 cannot be used to identify people at risk of dropping out from a PR program. Fact 3: PR improves exercise capacity, symptoms and health status across all grades of COPD severity. Improvements in the abovementioned outcomes have been reported in people with a variety of baseline FEV1 values.27, 28 Moreover, baseline FEV1 (alone or in combination with other lung function attributes) does not predict whether or not people with COPD achieve the minimal important difference for exercise capacity, health status, fatigue, anxiety and/or depression following PR.5, 7, 29-31 So, baseline FEV1 cannot be used to identify responders or non-responders. To conclude, FEV1 has no added to value as selection criterion for PR in people with COPD. Therefore, the respiratory community needs to foster adequate referral to exercise-based interventions, including center-based pulmonary rehabilitation, without using FEV1 as a referral criterion.32 Consequently, an interdisciplinary assessment must go far beyond the regular lung function tests, and should include also patients' physical, emotional and social status.18, 33 Frits M. E. Franssen has received grants and personal fees from AstraZeneca, and personal fees from Boehringer Ingelheim, Chiesi, GSK and Novartis. Martijn A. Spruit received grant from Netherlands Lung Foundation, Stichting Astma Bestrijding, all paid to Ciro. Moreover, he received grants and/or personal fees from AstraZeneca, Boehringer Ingelheim, Chiesi and Teva, all paid to Ciro.