Table 3– Results of stepwise multivariate Cox proportional hazard model
VariablesHR (95% CI)p-value
MMRC score2.181 (1.333–3.568)0.0019
Lowest Sp,O2 %0.952 (0.924–0.981)0.0014
  • Variables that were significant in univariate analysis (table 2) were included in the analysis. Lowest arterial oxygen saturation measured by pulse oximetry (Sp,O2) is a 6-min walk test variable. MMRC: modified Medical Research Council. #: n = 87, because patients for whom all data were available were included in the analysis; 46 of these patients (52.9%) died during the observation period.