Pitta F, Troosters T, Probst VS, Langer D, Decramer M, Gosselink R Chest. Published online April 10, 2008; doi:10.1378/chest.07-2655.
Background: Despite a variety of benefits brought by pulmonary rehabilitation to patients with chronic obstructive pulmonary disease, it is unclear whether these patients are more active during daily life after the program.
Methods: Physical activities in daily life (activity monitoring), pulmonary function (spirometry), exercise capacity (incremental cycle-ergometer test and 6-minute walking distance [6MWD]), muscle force (quadriceps and handgrip force, inspiratory and expiratory maximal pressures), quality of life (Chronic Respiratory Disease Questionnaire [CRDQ]), and functional status (Pulmonary Functional Status and Dyspnea Questionnaire-modified version [PFSDQ-M]) were assessed at baseline, after 3 months, and at the end of a 6-month multidisciplinary rehabilitation program in 29 patients (age 67 +/- 8 years; forced expiratory volume in the first second 46 +/- 16% predicted).
Results: Exercise capacity, muscle force, quality of life, and functional status improved significantly after 3 months of pulmonary rehabilitation (all P < .05), with further improvements in muscle force, functional status, and quality of life at 6 months. Movement intensity during walking improved significantly after 3 months (P = .046) with further improvements after 6 months (P = .0002). Walking time in daily life did not improve significantly at 3 months (7% +/- 35% improvement; P = .21) but only after 6 months (20% +/- 36% improvement; P = .008). No significant changes occurred in other activities or in the pattern of time spent walking in daily life. Changes in dyspnea after the program were significantly related to changes in walking time in daily life (r = 0.43; P = .02).
Conclusion: If one aims at changing physical activity habits in daily life of COPD patients, the contribution of long-lasting programs might be important.
Editor's Comment. The question asked by the title of the study is clear enough but its implications are harder to grasp. Is the goal of pulmonary rehabilitation merely an increase in level of activity (here narrowed down to time spent walking) or is it a more global improvement of function (some combination of an increased level of physical activity and a reduction in the level of discomfort associated with any given level of exertion)? Combining a 29% dropout rate (12 of 41, with 7 not being motivated enough) with the absence of a significant increase in time spent walking after 3 and 6 months of rehabilitation, would argue that longer programs may not be the way to increase the long-term benefits of pulmonary rehabilitation, and that some other strategies are required. What these other strategies might be are unclear, and it remains a constant challenge to get an aging population with chronic cardiorespiratory diseases to exercise. Some gains beyond the increased ability to exercise for exercise's sake have to be obvious to such patients for any long-term behavior modification intervention, especially one involving discomfort, to succeed.
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