Six-minute walk distance and dyspnoea scores to assess the course of COPD exacerbation in elderly patients

Introduction While the severity of stable chronic obstructive pulmonary disease (COPD) has been defined in a valid and relevant prognostic manner, parameters that describe the course of COPD exacerbations are not yet established. Physical performance and dyspnoea are of prognostic relevance in stable COPD. The issue investigated was to assess the course of COPD exacerbations to find parameters that describe this situation better. Methods In 82 hospitalised patients with acute exacerbation of COPD who responded to intensified medical treatment (age 67.3 +/- 9.5years; forced expiratory volume in 1s 1.0l, 40% predicted), we measured the 6-min walk distance and the visual analogue scale dyspnoea scores before the start of treatment, prior to discharge and after a 4-week stable period. Additionally, the conventional clinical parameters of COPD and quality of life were documented. Results The 6-min walk distance was significantly increased from 97 +/- 114m to 290 +/- 106m. After 4weeks of outpatient treatment in clinically stable patients, the 6-min walk distance fell non-significantly to 270 +/- 120m. The increment in walk distance fell significantly with advancing severity of COPD: from 112 +/- 68m for grade I and II to 56 +/- 88m for grade IV. Resting as well as exertional dyspnoea scores were significantly reduced (resting dyspnoea from 4 to 2 and exertional dyspnoea from 8 to 6). Conclusion We were able to demonstrate that 6-min walk test and dyspnoea scores, but not pulmonary function test, are suitable parameters to assess the course of COPD exacerbations.