Table 2.
Body plethysmography and single breath helium dilution with CO-diffusion (SB) parameters.
| Controls | GOLD1 | GOLD2 | GOLD3 | GOLD4 | |
|---|---|---|---|---|---|
| Body plethysmography (BP) | |||||
| R in, cmH2O∗s/L | 2.0 (1.6–2.4) | 2.0 (1.6–2.8) | 3.0 (2.1–3.2)** | 3.6 (2.8–5.3)∗∗∗†††‡‡ | 35.4 (4.6–6.6)∗∗∗††† ‡‡‡## |
| R ex, cmH2O∗s/L | 3.2 (2.4–3.7) | 2.7 (2.3–4.4) | 4.8 (3.2–6.8)∗∗†† | 13.2 (5.1–21.0)∗∗∗†††‡‡ | 21.2 (14.1–33.1)∗∗∗†††‡‡‡# |
| IC, L | 3.2 (2.7–3.8) | 3.0 (2.7–3.7) | 2.7 (2.4–3.2) | 2.3 (1.9–3.0)∗∗∗†† | 1.4 (1.0–2.6)∗∗∗†††‡‡ |
| IC, %p | 101 (88–108) | 97 (88–108) | 85 (73–98)† | 77 (67–91)∗∗∗†† | 52 (31.66)∗∗∗†††‡‡## |
| RVBP, L | 2.5 (2.2–2.9) | 2.5 (2.3–3.0) | 2.8 (2.4–3.1) | 3.6 (3.2–4.8)∗∗∗†††‡‡‡ | 4.5 (4.3–5.3)∗∗∗†††‡‡‡# |
| RVBP, %p | 111 (98–120) | 115 (105–124) | 124 (100–144) | 174 (148–187)∗∗∗†††‡‡‡ | 217 (193–245)∗∗∗†††‡‡‡## |
| TLCBP, L | 6.4 (5.4–7.3) | 6.7 (5.7–8.1) | 6.2 (5.7–7.1) | 7.3 (6.0–7.7) | 7.0 (5.7–7.6) |
| TLCBP, %p | 105 (97–111) | 108 (107–117)* | 104 (88–123) | 113 (107–126)** | 121 (100–138)∗∗‡ |
| FRCBP, L | 3.1 (2.6–3.4) | 3.4 (3.0–4.1)* | 3.6 (3.2–4.0)** | 4.4 (3.9–5.7)∗∗∗†‡‡ | 5.4 (4.6–5.8)∗∗∗†††‡‡‡ |
| FRCBP, %p | 94 (88–108) | 109 (102–120)** | 106 (91–142)* | 135 (123–152)∗∗∗†††‡‡ | 172 (161–203)∗∗∗†††‡‡‡## |
|
| |||||
| Single breath helium dilution with carbon monoxide diffusion (SB) | |||||
| DLCOSB, mmol/min/kPa | 6.2 (5.3–7.1) | 5.6 (4.5–7.7) | 5.2 (4.6–6.3)** | 3.0 (2.4–4.5)∗∗∗†††‡‡‡ | 1.8 (1.1–2.5)∗∗∗†††‡‡‡### |
| DLCOSB, %p | 75 (69–83) | 75 (53–87) | 63 (53–70)*** | 40 (32–46)∗∗∗†††‡‡‡ | 22 (15–29)∗∗∗†††‡‡‡### |
| VA, L | 5.3 (4.7–5.3) | 5.6 (4.9–5.6) | 4.8 (4.2–5.7)† | 4.4 (4.0–5.2)∗†† | 3.7 (3.1–4.5)∗∗∗†††‡‡‡ |
| VA, %p | 90 (83–97) | 96 (93–103)* | 84 (74–89)∗††† | 78 (64–83)∗∗∗††† | 67 (58–77)∗∗∗†††‡‡‡ |
| DLCOSB/VA, mmol/min/kPa/L | 1.2 (1.1–1.3) | 1.1 (0.9–1.2)* | 1.1 (0.9–1.3)* | 0.71 (0.64–0.83)∗∗∗†††‡‡‡ | 0.46 (0.35–0.56)∗∗∗†††‡‡‡### |
| DLCOSB/VA, %p | 89 (78–95) | 73 (61–90)* | 76 (64–93)* | 50 (45–60)∗∗∗††‡‡‡ | 35 (23–41)∗∗∗†††‡‡‡### |
| RVSB, L | 1.9 (1.7–2.0) | 2.0 (1.6–2.3) | 1.7 (1.5–2.0)† | 1.5 (1.3–1.9)∗∗† | 1.6 (1.3–1.8)* |
| RVSB, %p | 81 (72–87) | 90 (77–96) | 77 (64–89) | 67 (59–79)∗† | 69 (58–95) |
| TLCSB, L | 5.5 (4.9–6.2) | 5.8 (5.1–7.1) | 5.0 (4.4–5.9)† | 4.6 (4.1–5.3)∗†† | 3.9 (3.3–4.7)∗∗∗†††‡‡‡ |
| TLCSB, %p | 91 (85–97) | 97 (93–103)* | 85 (75–90)∗††† | 79 (65–84)∗∗∗††† | 68 (60–77)∗∗∗†††‡‡‡ |
| FRCSB, L | 2.5 (2.1–2.7) | 3.0 (2.8–3.2)** | 2.5 (2.1–2.8)† | 2.1 (1.6–2.9)† | 2.4 (1.8–2.9)†††‡‡‡ |
| FRCSB, %p | 75 (67–87) | 93 (81–104)** | 76 (66–91)†† | 71 (56–80)†† | 69 (61–102)†††‡‡‡ |
|
| |||||
| Difference between BP and SB | |||||
| RV %pBP−SB | 28 (19–40) | 33 (23–40) | 43 (29–62)∗† | 95 (80–129)∗∗∗†††‡‡‡ | 149 (119–192)∗∗∗†††‡‡‡## |
| TLC %pBP−SB | 14 (11–18) | 14 (11–18) | 18 (13–27)* | 35 (30–49)∗∗∗†††‡‡‡ | 57 (39–70)∗∗∗†††‡‡‡# |
*Significant difference compared to healthy smokers, †significant difference compared to GOLD1, ‡significant difference compared to GOLD2, #significant difference compared to GOLD3, one symbol flagging P < 0.05, two symbols flagging P < 0.01 and three symbols flagging P < 0.001. All data are presented as median (interquartile range).