Study | Population | Relevant outcome measure(s) | Finding |
---|---|---|---|
Jones et al. 2017 [43] | Mild to moderate COPD (post-bronchodilator FEV1 ≥ 60% predicted); controls without COPD | Incremental exercise test | Increased dyspnoea and ventilatory inefficiency in mild-to-moderate COPD versus controls |
Caram et al. 2016 [44] | Never smokers; smokers with/without mild-to-moderate COPD (post-bronchodilator FEV1 > 50% predicted) | 6MWT | Lower exercise capacity in mild-to-moderate COPD versus never smokers |
Vaz Fragoso et al. 2016 [28] | 6MWT | Lower exercise capacity in mild COPD versus controls (non-significant) | |
Elbehairy et al. 2015 [47] | Mild COPD; non-smoker controls | Symptom-limited cycle test | Gas exchange abnormalities with increased dyspnoea and exercise intolerance in mild COPD versus controls |
Neder et al. 2015 [48] | COPD; controls without COPD | Symptom-limited cycle test | Increased ventilatory inefficiency and reduced exercise capacity in mild COPD versus controls |
Guenette et al. 2014 [49] | Mild COPD; controls without COPD | Symptom-limited cycle test | Increased ventilatory requirements and respiratory effort during exercise in mild COPD versus controls |
Chin et al. 2013 [50] | Mild COPD; controls without COPD | Symptom-limited cycle test | Reduced peak O2 uptake; no peak end-inspiratory lung volume increase in mild COPD versus controls |
DÃaz et al. 2013 [51] | Dyspnoeic (mMRC score ≥ 1) and non-dyspnoeic patients with mild COPD; smoker controls | Borg dyspnoea rating, 6MWT | Decreased inspiratory capacity and increased ventilatory demand during exercise and reduced exercise capacity in dyspnoeic COPD versus non-dyspnoeic COPD or controls |
Watz et al. 2009 [41] | COPD; controls with chronic bronchitis | Steps/day, minutes of at least moderate activity, 6MWT | Higher proportion of sedentary patients in mild COPD versus chronic bronchitis |
Ofir et al. 2008 [52] | Symptomatic current or former smokers with mild COPD; age- and sex-matched former or non-smoker controls | Symptom-limited cycle test, Borg dyspnoea rating | Increased ventilatory requirements and exertional dyspnoea, decreased peak O2 uptake in mild COPD versus controls |
Carter et al. 1993 [53] | COPD (FEV1/FVC, 0.6–0.7; FEV1 ≥ 60% predicted); controls without COPD | Resting and peak exercise gas exchange (with symptom-limited cycle test) | Decreased maximal oxygen consumption and ventilation, reduced work capacity and maximal heart rate in COPD versus controls |