Table 5. Multivariate analysis according to the 6-minute walking distance (m) as dependent variable.

Independent variables	Coefficient β (95% CI)	p-value
(Constant: 368, 20 m)
E/A ratio	76,16 (12,1 to 140,2)	0.012*
Smoking, pack-years	-0,78 (-1,54 to -0,02)	0.043*
DLCO, quartile 4th	-57,05 (-101,3 to -12,8)	0.021*

Definition of abbreviations: CI = confidence interval; E/A ratio = ratio of early (E) to late (A) mitral flow peak velocities; DLCO = diffusing capacity for carbon monoxide. * A p value of <0.05 was considered to be statistically significant.