Minimal clinically important differences in COPD: body mass index and muscle strength.

Weight loss, muscle wasting, as well as muscle dysfunction are recognized as important problems in COPD, contributing to morbidity and mortality. This paper discusses body weight and muscle function as possible outcome parameters in the management of COPD. The relationship between these outcome measures and COPD-related management goals is discussed. Minimal clinically important differences (MCID) in the approach of patients suffering from COPD for these measures are discussed.