Benefits of ambulatory oxygen during physical activity in patients with COPD who desaturate only during exercise

Long-term oxygen is standard of care therapy for COPD patients hypoxemic at rest. Evidence of benefit is less clear for COPD patients hypoxemic only during ambulation. We studied effects of ambulatory O₂, to be used during physical activity, in COPD patients normoxic at rest but hypoxemic (SpO₂<88%) during a 6-min walk test (6MWT). Subjects with COPD, 70±9 years, 42% female, FEV₁% predicted 40±19, resting PaO₂ 9.1±0.9 kPa, who were willing to be physically active were included. They were randomized to supplemental O₂ (liquid oxygen in a 1.5 kg device, Helios Plus 300) during physical activity (n=78, O₂ group) or no supplemental O₂ (n=77, control group) for 6 months. All received regular motivational telephone interviews by a physiotherapist, encouraging ≥150 min of physical activity/week; daily physical activity time was recorded in a diary. O₂ group subjects recorded daily O₂ use time. Adherence to supplemental O₂ was defined as ≥70% of physical activity time. At baseline and 6 months, subjects performed spirometry and 6MWT (breathing air); symptoms were assessed by COPD Assessment Test (CAT). There were no significant differences between groups at baseline and change at 6 months did not differ between groups (Table). In conclusion, we obtained no evidence of supplemental O₂ benefit for COPD subjects who desaturate only during ambulation. <table-wrap><object-id>erj;64/suppl_68/PA1365/TB1</object-id><object-id>T1</object-id><object-id>TB1</object-id><table><colgroup><col></col><col></col><col></col><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td> O₂ group </td><td> O₂ group </td><td> Control group </td><td> Control group </td><td> P-value: change between groups </td></tr><tr><td></td><td> Baseline n=64 </td><td> 6 months n=64 </td><td> Baseline n=64 </td><td> 6 months n=64 </td><td> </td></tr><tr><td>6 MWD (m)</td><td>353</td><td>334</td><td>383</td><td>375</td><td>0.09</td></tr><tr><td>FEV₁ (L)</td><td>0.97</td><td>0.92</td><td>1.08</td><td>1.03</td><td>0.61</td></tr><tr><td>CAT</td><td>17</td><td>17</td><td>17</td><td>17</td><td>0.83</td></tr></tbody></table></table-wrap>