Cardiopulmonary testing measurements
| Cardiopulmonary exercise testing outputs | All (N=245) | Unexposed (N=106) | Exposed (N=139) | P value |
| Cardiopulmonary testing measurements | ||||
| VO2Peak (L/min) | 1.557±0.476 | 1.800±0.532 | 1.372±0.324 | <0.001 |
| VO2Peak (% predicted) | 100±24 | 102±28 | 98±21 | 0.388 |
| Reached 100% predicted VO2Peak (n (%)) | 114 (46.5) | 52 (49.1) | 62 (44.6) | 0.787 |
| VO2Peak <100% predicted | 131 (53.5) | 54 (50.9) | 77 (55.4) | 0.787 |
| VO2Peak <84% predicted | 71 (29.0) | 30 (28.3) | 41 (29.5) | 0.979 |
| VO2Peak/kg (mL/min.kg) | 23.82±7.02 | 27.15±7.32 | 21.28±5.59 | <0.001 |
| VO2Peak/kg (% predicted) | 85±18 | 86±21 | 84±16 | 0.657 |
| VO2Peak/kg < LLN (n (%)) | 33 (13.5) | 21 (19.8) | 12 (8.6) | 0.039 |
| VCO2Peak (L/min) | 1.90±0.59 | 2.20±0.64 | 1.67±0.43 | <0.001 |
| WattsPeak (watts) | 156±46 | 181±46 | 137±36 | <0.001 |
| WattsPeak (% predicted) | 135±33 | 142±35 | 130±31 | 0.020 |
| Watts per stage (watts) | 27±8 | 30±7 | 24±7 | <0.001 |
| Cumulative work (watt-minute) | 566±229 | 661±252 | 491±178 | <0.001 |
| Stages completed | 6.0±1.3 | 6.1±1.3 | 6.0±1.3 | 0.631 |
| Symptoms at peak exercise (modified Borg Dyspnoea Scale 0–10) | ||||
| Shortness of Breath | 4.2±1.9 | 4.2±1.9 | 4.2±1.9 | 0.996 |
| Effort | 5.1±1.9 | 5.5±1.9 | 4.9±1.9 | 0.063 |
| Fatigue | 4.7±1.9 | 4.9±1.8 | 4.6±1.9 | 0.342 |
| DyspnoeaPeak (n (%)) | 117 (49.6) | 43 (41.0) | 74 (56.5) | 0.06 |
| Pulmonary response | ||||
| VEPeak (L/min) | 57.04±16.97 | 63.86±18.43 | 51.84±13.71 | <0.001 |
| VEPeak (% predicted) | 50±12 | 50±12 | 50±12 | 0.940 |
| RER | 1.21±0.13 | 1.22±0.12 | 1.21±0.13 | 0.702 |
| RRPeak (breaths/min) | 34.7±9.0 | 36.1±9.4 | 33.6±8.5 | 0.115 |
| RRPeak ≥60 (n/235 (%)) | 1 (0.4) | 1 (1.0) | 0 (0) | 0.520 |
| VTPeak (L) | 1.73±0.47 | 1.88±0.52 | 1.62±0.38 | <0.001 |
| VTPeak (% predicted) | 86±17 | 87±17 | 86±17 | 0.881 |
| VE/VO2Peak | 37.1±6.2 | 36.0±6.0 | 37.9±6.2 | 0.066 |
| VE/VCO2Peak | 30.7±3.8 | 29.7±3.9 | 31.5±3.5 | <0.001 |
| VE/VCO2Peak ≥34 (n (%)) | 51 (20.8) | 15 (14.2) | 36 (25.9) | 0.080 |
| VE/VCO2Peak (% predicted) | 108±12 | 107±14 | 109±11 | 0.729 |
| VE/VCO2Lowest | 29.4±3.4 | 28.2±3.2 | 30.3±3.3 | <0.001 |
| VE/VCO2Lowest (% predicted) | 103±11 | 102±10 | 104±11 | 0.220 |
| VO2 at anaerobic threshold (VO2AT) (L/min) | 0.99±0.33 | 1.17±0.35 | 0.87±0.25 | <0.001 |
| VO2 at anaerobic threshold (VO2AT) (%VO2Peak) | 63±13 | 63±13 | 63±13 | 0.984 |
| VO2AT ≤40% VO2Peak (n/202 (%)) | 11 (5.5) | 3 (3.7) | 8 (6.7) | 0.652 |
| VE/VCO2 at anaerobic threshold | 31.4±3.9 | 29.6±3.2 | 32.7±3.8 | <0.001 |
| VE/VCO2 at anaerobic threshold (% predicted) | 103±11 | 101±10 | 105±12 | 0.082 |
| Cardiovascular response | ||||
| HRBaseline (beat/min) | 67.5±12.4 | 66.5±12.3 | 68.3±12.6 | 0.531 |
| HRPeak (beat/min) | 141.8±17.9 | 146.9±14.2 | 138.0±19.5 | <0.001 |
| HRPeak (% predicted) | 85±10 | 85±8 | 86±12 | 0.911 |
| HRPeak ≤90% predicted (n (%)) | 165 (67.3) | 84 (79.2) | 81 (58.3) | 0.002 |
| HRR | 24±17 | 26±15 | 23±19 | 0.394 |
| HRR ≥15 (n (%)) | 176 (71.8) | 89 (84.0) | 87 (62.6) | 0.001 |
| HRSlope (beat/min/10 Watts) | 4.73±1.19 | 4.42±1.03 | 4.99±1.25 | <0.001 |
| SBPBaseline (mm Hg) | 121.1±15.5 | 118.1±14.1 | 123.6±16.2 | 0.023 |
| SBPPeak (mm Hg) | 178.8±20.3 | 178.9±22.3 | 178.7±18.5 | 0.999 |
| SBPSlope (mm Hg/10 Watts) | 3.90±1.42 | 3.61±1.21 | 4.13±1.53 | 0.017 |
| DBPBaseline (mm Hg) | 76.5±8.9 | 76.0±9.0 | 76.8±8.9 | 0.815 |
| DBPPeak (mm Hg) | 93.1±9.8 | 93.7±8.9 | 92.5±10.6 | 0.657 |
| DBPSlope (mm Hg/10 Watts) | 1.17±0.72 | 1.07±0.62 | 1.24±0.79 | 0.187 |
| HRE (met at least one criterion) (n/226 (%)) | 149 (65.9) | 73 (71.6) | 76 (61.3) | 0.268 |
| Rise in SBP ≥50 mm Hg (≥60 mm Hg for men) | 138 (61.1) | 69 (67.6) | 69 (55.6) | 0.184 |
| SBPPeak ≥190 mm Hg (≥210 mm Hg for men) | 45 (19.9) | 20 (19.6) | 25 (20.2) | 0.995 |
| DBPPeak ≥105 mm Hg | 24 (10.6) | 12 (11.8) | 12 (9.7) | 0.879 |
| O2-PulsePeak (mL/beat) | 11.0±3.0 | 12.3±3.5 | 10.0±2.2 | <0.001 |
| O2-PulsePeak (% predicted) | 116±25 | 120±27 | 114±23 | 0.191 |
| Reached 100% predicted O2-PulsePeak (n (%)) | 181 (73.9) | 84 (79.2) | 97 (69.8) | 0.248 |
| O2-PulsePeak <100% predicted (n (%)) | 64 (26.1) | 22 (20.8) | 42 (30.2) | 0.248 |
| O2-PulsePeak ≤80% predicted (n (%)) | 8 (3.3) | 3 (2.8) | 5 (3.6) | 0.946 |
| O2-PulseBaseline (mL/beat) | 3.8±1.0 | 4.1±1.1 | 3.6±0.9 | <0.001 |
| O2-PulseSlope (mL/beat/Watt) | 0.47±0.11 | 0.46±0.09 | 0.49±0.12 | 0.070 |
| O2-Pulse at anaerobic threshold (mL/beat) | 9.1±3.6 | 10.5±4.0 | 8.4±3.2 | 0.003 |
| O2-Pulse at anaerobic threshold (% O2-PulsePeak) | 84±30 | 86±37 | 83±25 | 0.912 |
| SpO2Baseline | 99±1 | 99±1 | 99±1 | 0.983 |
| SpO2Peak | 98±1 | 99±1 | 98±1 | 0.699 |
| Change in SpO2 at peak exercise | −0.59±1.4 | −0.5±1.6 | −0.6±1.3 | 0.815 |
Cardiopulmonary measurements in participants who underwent exercise testing. Data are presented as mean±SD. Data are presented as mean±SD. Reference equations: per cent predicted of normal values of cardiopulmonary outputs were calculated using Wassermann et al predicted formulas.20
HRPeak, peak heart rate; HRR, heart rate reserve; O2-PulsePeak, oxygen uptake per heartbeat at peak exercise; RER, respiratory exchange ratio (VCO2/VO2) at peak exercise; RRPeak, peak respiratory rate; VCO2Peak, peak carbon dioxide production; VEPeak, peak minute ventilation value; VO2Max.kg, peak oxygen uptake per kilogram of body weight; VO2Peak, peak oxygen uptake; VTPeak, peak tidal volume; WattsPeak, peak work stage completed in watts.