Why chronic obstructive pulmonary disease patients get so short of breath with limited activity
equivalence despite the simplicity of MPT versus CPET as a surrogate to detect DH in COPD patients, by measuring the decrease in inspiratory capacity to reflect the increase in end-expiratory lung volume [3] . Lahaije et al. [2] have investigated whether DH as measured in the laboratory settings (CPET and MPT) reflects DH that is associated with dyspnea-limiting ADL. The authors conclude that both CPET and MPT can serve as a screening tool to identify patients who are susceptible to develop DH during ADL. In practice, MPT is simpler to obtain and is an inexpensive surrogate. However, sensitivity of MPT may not be optimal. When DH does not occur during CPET, it is unlikely to occur during AD…