TABLE 4.
Cardiopulmonary exercise test data for the study population
| Control subjects | WTC Dust | Clinical referral | |
| Subjects n | 13 | 20 | 15 |
| Baseline Borg dyspnoea | 0.0±0.0 | 1.4±1.5* | 0.8±1.5 |
| Peak Borg dyspnoea | 3.1±2.3 | 4.2±2.3 | 5.8±2.5* |
| P eak V′O2 % pred | 100±28 | 82±12* | 91±14 |
| Peak HR % pred | 93±10 | 81±11* | 90±12 |
| Peak RR breaths·min−1 | 38±12 | 36±6 | 41±14 |
| Peak VT L | 2.21±0.70 | 1.35±0.62* | 1.88±0.46 |
| Peak VT / VC % | 50±8 | 42±7 | 52±13 |
| Peak V′E L·min−1 | 88±26 | 52±22* | 80±23 |
| Peak V′E/MVV % | 74±29 | 54±16* | 77±19 |
| Peak RQ | 1.26±0.13 | 1.16±0.10* | 1.15±0.11* |
| V′E/V′CO2 (at anaerobic threshold) | 28.5±3.2 | 29.8±3.7 | 31.2±2.2 |
| O2 pulse % pred | 114±36 | 99±15 | 110±23 |
| Anaerobic threshold (% of pred V′O2 max) | 57±11 | 56±7 | 57±9 |
Data are reported as mean±sd. V′O2: peak oxygen uptake; HR: heart rate; RR: respiratory rate; VT : tidal volume; V′E: minute ventilation; MVV: maximum voluntary ventilation. *: p<0.05 versus control.