Outcome measures at baseline, after 6 weeks of RMT and after 1 year of unsupervised training
| Sham RMT group | Active RMT group | |||||||
| Baseline (n=32) | 6 weeks (n=31) | 1 year (n)* | Baseline (n=30) | 6 weeks (n=29) | 1 year (n)* | P value at 6 weeks | P value at 1 year | |
| Primary outcome | ||||||||
| PImax (cmH2O) | 51.5±19.7 | 54.9±21.3 | 63.0±29.0 (15) | 48.4±22.6 | 63.7±24.0 | 70.2±32.2 (19) | < 0.001 | 0.081 |
| Secondary outcomes | ||||||||
| PEmax (cmH2O) | 33.2±14.0 | 37.4±17.8 | 36.2±16.5 (15) | 32.8±18.2 | 38.4±21.7 | 44.6±20.5 (18) | 0.799 | 0.075 |
| Lung function | ||||||||
| FEV1 (L) | 1.9±0.7 | 1.9±0.8 | 2.0±1.0 (16) | 1.8±0.8 | 1.8±0.8 | 2.1±0.8 (19) | 0.385 | 0.674 |
| FVC (L) | 2.5±0.9 | 2.6±1.0 | 2.9±1.4 (16) | 2.3±1.0 | 2.5±1.1 | 2.8±1.0 (19) | 0.349 | 0.600 |
| Inspiratory capacity (L) | 2.1±0.7 | 2.1±0.8 | 1.6±0.7 (7) | 2.0±0.7 | 2.0±0.8 | 2.2±0.5 (11) | 0.979 | 0.077 |
| PEFc (L/s) | 4.6±1.6 | 4.7±1.8 | 4.2±1.8 (8) | 4.6±1.5 | 4.7±1.6 | 5.4±1.8 (11) | 0.893 | 0.659 |
| Vital capacity (L) | 2.6±0.9 | 2.7±1.1 | 2.8±1.4 (7) | 2.3±0.8 | 2.5±1.0 | 3.0±0.9 (11) | 0.126 | 0.391 |
| Total lung capacity (L) | 4.8±1.3 | 4.9±1.2 | 4.3±1.8 (4) | 5.0±1.1 | 5.1±1.3 | 5.0±1.0 (7) | 0.402 | 0.689 |
| Respiratory complications (n) | 0 | 6 | 10 (19)† | 0 | 2 | 3 (22)† | 0.257 | 0.017 |
| Quality of life: Short Form-36 (SF-36ww) | ||||||||
| Physical functioning | 36.4±34.9 | 41.6±38.1 | 41.9±29.3* | 38.0±32.2 | 54.0±32.8 | 44.9±28.4* | 0.426 | 0.761 |
| Role limitations (physical) | 38.2±43.4 | 57.8±46.3 | 46.2±43.1 | 50.0±41.2 | 75.0±39.5 | 68.1±42.7 | 0.824 | 0.759 |
| Role limitations (emotional) | 68.6±44.9 | 75.0±41.3 | 79.5±34.9 | 73.4±36.1 | 89.8±21.0 | 72.2±40.0 | 0.865 | 0.629 |
| Energy/fatigue | 50.0±21.9 | 51.1±22.6 | 59.2±17.8 | 53.0±19.4 | 56.2±27.9 | 54.7±21.3 | 0.763 | 0.994 |
| Emotional well-being | 74.8±17.3 | 73.0±26.1 | 78.2±7.8 | 74.1±17.2 | 70.1±19.6 | 72.4±16.4 | 0.801 | 0.899 |
| Social functioning | 50.8±36.8 | 68.1±30.6 | 64.6±28.8 | 67.7±26.2 | 75.2±31.7 | 64.1±31.8 | 0.398 | 0.200 |
| Pain | 60.3±26.8 | 71.9±24.6 | 79.5±23.3 | 53.9±22.6 | 58.2±28.9 | 62.7±29.7 | 0.419 | 0.946 |
| General health | 53.8±26.4 | 60.3±27.0 | 56.5±24.0 | 51.3±23.6 | 60.4±28.5 | 56.1±20.4 | 0.991 | 0.986 |
| Quality of life: EQ-5D VAS | 54.8±22.9 | 63.5±21.1 | 68.1±15.2 | 58.7±21.4 | 68.9±22.3 | 59.7±18.2 | 0.541 | 0.877 |
| Perceived breathlessness (Borg score) | ||||||||
| At rest | 0.8±1.0 | 0.5±0.7 | 0.7±0.9* | 0.8±1.1 | 1.0±1.6 | 1.0±1.6* | 0.021 | 0.313 |
| Inspiratory loaded breaths | 3.4±2.0 | 3.3±2.2 | N/A | 2.9±2.1 | 1.7±1.5 | N/A | 0.049 | N/A |
| Expiratory loaded breaths | 4.3±2.4 | 3.9±2.0 | N/A | 3.4±1.7 | 2.5±1.9 | N/A | 0.494 | N/A |
| SGRQ | ||||||||
| Symptom severity score | 21.4±17.5 | 26.2±23.8 | 13.9±16.2* | 25.2±18.8 | 20.5±18.7 | 23.0±19.8* | 0.046 | 0.821 |
| Activity score | 9.0±12.0 | 4.9±7.6 | 5.7±6.1 | 13.2±15.6 | 3.1±5.2 | 2.7±5.0 | 0.485 | 0.765 |
| Impacts score | 18.9±18.5 | 14.7±14.9 | 15.1±13.3 | 17.1±18.5 | 10.9±12.1 | 10.5±12.1 | 0.838 | 0.601 |
| Total score | 15.1±12.8 | 13.3±13.1 | 11.2±10.5 | 16.5±15.4 | 9.9±9.6 | 9.7±10.0 | 0.451 | 0.573 |
Data shown as mean±SD.
N/A as data for this outcome not collected at this time point.
Bold p values indicate significance at level p<0.05.
*Due to missing values at the 1-year follow-up, the number of data points for each outcome is shown in brackets beside each value for PImax, PEmax and lung function measures; SF-36, Borg score and SGRQ all had 13 data points for sham RMT and 18 data points for active RMT at 1-year follow-up.
†Includes number of respiratory complications from initial 6 weeks of training for a 1 year total.
EQ-5D VAS, EuroQol-Five Dimensional Visual Analogue Scale questionnaire; PEFc, peak expiratory cough flow; PEmax, maximal expiratory pressure; PImax, maximal inspiratory pressure; RMT, respiratory muscle training; SF-36ww, Short Form Health Survey: walk/wheel; SGRQ, St George Respiratory Questionnaire.