FIG. 55: Some of the earlier work in COPD suggested that the addition of home ventilation may be a burden to patients and may actually be associated with a reduction in HRQOL. This was a concern to us as investigators and clinicians. Although we were keen to show an improvement in the primary outcome (admission-free survival), we also wanted to ensure that there was no evidence that the therapy was a burden to patients or was associated with a deterioration in QOL.

This Figure shows the results of the SRI score (y-axis) as a global measure of HRQOL in patients with respiratory failure.[1] There was an early improvement within the first 6 weeks of the trial, but then a slow reduction in difference between the arms as the trial continued. This may merely represent the progressive nature of the severity of COPD, or it may mean that significant numbers of patients had home ventilation added (even in the control arm, due to breach of safety criteria) and this may have diluted the physiologic and clinical effects at these time points.