Abstract
BACKGROUND: Empirical evidence supports the role of exercise as part of pulmonary rehabilitation in improving symptoms of breathlessness (dyspnea), health-related quality of life, and exercise tolerance among patients with chronic lung disease. However, many studies show that these initial benefits tend to diminish 12 to 18 months after rehabilitation. Given the importance of exercise (ie, walking) during rehabilitation, we examined whether patient adherence to regular walking enhanced the long-term maintenance of functional benefits gained from an 8-week pulmonary rehabilitation program.
METHODS: One hundred twenty-three patients with moderate to severe chronic lung disease completed an 8-week pulmonary rehabilitation program and participated in a 12-month maintenance intervention trial. Measures of weekly walking, lung function, self-efficacy for walking, dyspnea during activities of daily living, exercise capacity (6-minute walk test, 6MW), perceived breathlessness after the 6MW, and health-related quality of life were obtained at postrehabilitation, and at 6, 12, and 24 months after completing pulmonary rehabilitation. Regular walkers were defined as those active on most days or every single day of the week on the average throughout the 24-month period, whereas irregular walkers walked on some days, rarely, or not at all.
RESULTS: The effects of the maintenance program on average frequency of walking were nonsignificant, with 44% of the maintenance patients and 38% of the standard care patients classified as regular walkers. There were no significant differences between walking groups on gender, healthcare utilization over the 24-month follow-up period, and postrehabilitation measures of lung function, 6MW distance, perceived breathlessness after 6MW, health-related quality of life, dyspnea, or age. Repeated measures analyses of variance using a 2 x 4 mixed model approach were applied to examine group differences and changes in outcomes over time. Overall, participants decreased in 6MW distance (P <.001), reported increases in perceived breathlessness after the 6MW (P <.05), and decreased in overall health-related quality of life (P <.001) from postrehabilitation to 24 months. Regular walkers reported significantly better health-related quality of life (P <.05) as compared to irregular walkers, averaging across time points. Irregular walkers declined significantly more than regular walkers on measures of shortness of breath during activities of daily living (P <.01) and walking self-efficacy (P <.001) from postrehabilitation to 24 months.
CONCLUSIONS: Findings suggest that participation in regular exercise such as walking after completing pulmonary rehabilitation is associated with slower declines in overall health-related quality of life and walking self-efficacy as well as less progression of dyspnea during activities of daily living. Regular exercise after rehabilitation may be protective against increases in dyspnea symptoms and perceived limitations in walking which are both characteristic of progressing chronic lung disease.