Chronic dyspnea is a distressing symptom that reduces health-related quality of life (HQOL). Breathing strategies such as pursed-lips breathing (PLB) are frequently encouraged by rehabilitation staff for dyspnea relief. However, contradictory evidence exists for breathing strategy efficacy. The study objective was to compare 3 methods for teaching a breathing strategy of prolonged, gentle exhalation on dyspnea relief and improved HQOL in patients with severe COPD.
53 subjects (mean±sd age = 66±9 years, forced expiratory volume 1sec (FEV1)/ forced vital capacity = 47±11, FEV1% pred = 38 ± 14, Body Mass Index (BMI) = 26±6, inspiratory muscle strength (PImax) = 71±22 cm H20) were randomized to either: 1) control; 2) inspiratory muscle training (IMT) at 30% PImax; 3) expiratory muscle training (EMT) at 10% PEmax; or 4) structured PLB with oxygen saturation level as feedback. Dyspnea measures of visual analogue scale, modified Borg, University of California, San Diego Shortness of Breath and HQOL measure of SF-36 were done at baseline, end of 4 weekly visits to the research laboratory, and 3 months. ANCOVA with planned post hoc analyses was used to explore differences among and between groups.
Group effect was present for the modified Borg after 6-minute walk distance (6MWD) (p = 0.016) and SF-36 domains of mental health (p = 0.037) with covariate PImax and physical function (0.023) with covariate BMI. Dyspnea was significantly different (p = 0.015) for the PLB group after 6MWD, but not IMT or EMT, as compared to the control group.
A significant decrease in dyspnea occurred with the PLB group after 6MWD at 3 months. The only group with sustained improvement in dyspnea, mental health and physical function occurred for the PLB group.
Decreased dyspnea after activity and improved HQOL may result with regular use of PLB for those with COPD.
M. Nield, None.