This multicenter prospective study demonstrated
that categorizing patients with COPD on the basis of
the level of dyspnea was more closely correlated with
survival than classification on the basis of disease
severity as assessed by the percentage of predicted
FEV1. Studies on the prognosis of patients with
COPD have utilized various objective indexes as
factors related to survival. The present study suggests
that categorization by the level of dyspnea may
be similarly useful in the prediction of survival.