Table 3.
Comparison of JRS stage I with and without oxygen desaturation on the 6MWT
| JRS stage I + desaturation (–) | JRS stage I + desaturation (+) | P value | |
|---|---|---|---|
| Age, years | 71.2 ± 6.9 | 71.9 ± 7.1 | 0.51 |
| Sex, male/female | 89/17 | 58/15 | 0.55 |
| BMI, kg/m2 | 22.1 ± 3.8 | 21.3 ± 4.3 | 0.22 |
| Smoking history, N/F/C | 16/71/19 | 6/50/17 | 0.31 |
| GAP staging (I/II/III) | 80/24/2 | 31/34/8 | < 0.0001 |
| mMRC (0/1/2/3/4) | 24/50/28/3/1 | 4/23/34/10/2 | < 0.0001 |
| PaO2, Torr | 91.7 ± 9.1 | 88.0 ± 8.4 | 0.007 |
| %FVC, % | 86.9 ± 18.4 | 73.7 ± 17.7 | < 0.0001 |
| %DLco, % | 76.2 ± 21.6 | 57.9 ± 15.4 | < 0.0001 |
| KL-6, U/ml | 797 ± 533 | 1140 ± 603 | < 0.0001 |
| SP-D, ng/ml | 221 ± 139 | 342 ± 278 | 0.0002 |
| 6MWD, m | 400 ± 95 | 368 ± 106 | 0.03 |
| Lowest SpO2 on 6MWT, % | 93.1 ± 2.2 | 85.9 ± 3.7 | < 0.0001 |
Data is presented as mean ± standard deviation. JRS, Japanese Respiratory Society; BMI, body mass index; N/F/C, never/former/current; GAP, gender–age–physiology; mMRC, modified Medical Research Council; PaO2, partial pressure of oxygen in arterial blood; FVC, forced vital capacity; DLco, diffusion capacity of the lungs for carbon monoxide; KL-6, Krebs von den Lungen-6; SP-D, surfactant protein-D; 6MWD, 6-min walking distance; SpO2, percutaneous oxygen saturation; 6MWT, 6-min walk test