Flow-Volume Parameters in COPD Related to Extended Measurements of Lung Volume, Diffusion, and Resistance

Table 4

Correlations between established flow-volume parameters and extended volume and resistance parameters.

	Volume		Resistance
	RV%pBP-SB	TLC%pBP-SB	𝑅in	𝑅ex	𝑅5--𝑅20	𝐹res
Flow-volume
FEV1%p
Controls	0.15	0.31	−0.01	0.06	−0.12	−0.21
GOLD1	0.50	−0.25	−0.18	−0.26	−0.27	−0.36
GOLD2	−0.37	−0.34	−0.19	−0.20	−0.26	−0.18
GOLD3	−0.21	0.12	−0.16	0.18	−0.3	−0.32
GOLD4	−0.33	−0.34	−0.14	−0.12	−0.14	−0.11
FVC%p
Controls	0.14	0.34	0.12	0.14	−0.05	−0.07
GOLD1	0.14	0.15	−0.19	−0.16	−0.22	−0.32
GOLD2	0.59 **	0.60 **	−0.35	−0.29	−0.29	−0.14
GOLD3	−0.14	0.01	−0.31	−0.05	−0.22	−0.2
GOLD4	−0.55 *	−0.21	−0.33	−0.45	−0.26	−0.11
FEV1/FVC
Controls	−0.02	−0.22	−0.26	−0.11	−0.19	−0.25
GOLD1	0.34	−0.07	−0.13	−0.29	−0.15	−0.13
GOLD2	−0.71 ***	−0.71 ***	0.12	0.09	0.15	0.08
GOLD3	−0.31	0.04	−0.08	0.35	−0.06	−0.14
GOLD4	0.69 **	0.37	0.32	0.58 *	0.24	0.05
IC%p
Controls	0.30	0.42*	0.07	−0.02	−0.06	−0.04
GOLD1	0.29	−0.04	0.61 *	0.73 **	−0.06	0.09
GOLD2	0.66 ***	0.63 **	0.06	0.29	0.11	0.10
GOLD3	0.11	0.46	−0.24	0.35	−0.3	−0.42
GOLD4	0.72 **	0.01	−0.36	−0.61 *	−0.61	−0.13
Resistance
𝑅5--𝑅20
Controls	−0.05	−0.12	0.43 **	0.37 *	—	0.85 ***
GOLD1	−0.26	0.00	0.44	0.21	—	0.94 ***
GOLD2	0.08	0.03	0.80 ***	0.88 ***	—	0.87 ***
GOLD3	0.04	0.22	0.64 *	0.44	—	0.86 ***
GOLD4	0.29	0.54 *	0.71 **	0.55	—	0.69 **
𝐹res
Controls	−0.04	−0.2	0.47 **	0.40 *	0.85 ***	—
GOLD1	−0.28	0.27	0.61 *	0.4	0.94 ***	—
GOLD2	0.08	0.02	0.63 **	0.77 ***	0.87 ***	—
GOLD3	0.13	0.26	0.50	0.41	0.86 ***	—
GOLD4	−0.05	0.13	0.61 *	0.47	0.69 **	—

Data are presented as 𝑟-values. ∗P < 0.05, ∗∗P < 0.01 ∗∗∗P < 0.001.