Tiotropium Respimat Soft Mist Inhaler versus HandiHaler to improve sleeping oxygen saturation and sleep quality in COPD

Patients with chronic obstructive pulmonary disease (COPD) have poor sleep quality as a result of various alterations in oxygenation parameters and sleep macro- and micro-architecture. There is a shortage of data to support the efficacy of long-acting inhaled anticholinergic agents in improving these adverse effects, which are known to have a negative impact on clinical outcomes. We aimed to compare the tiotropium Respimat Soft Mist Inhaler and the HandiHaler in terms of their effects on sleeping oxygen saturation (SaO(2)) and sleep quality in patients with COPD. In a randomized, open-label, parallel-group trial involving 200 patients with mild to moderate COPD (resting arterial oxygen tension > 60 mmHg while awake), we compared the effects of 6 months' treatment with the two devices on sleeping SaO(2) and sleep quality. Overnight polysomnography and pulmonary function testing were performed at baseline and after 6 months' treatment. A total of 188 patients completed the trial. Both groups showed significant improvement in minimum sleep SaO(2) and time of sleep spent with SaO(2) below 90 (TST90) compared to baseline. The patients using the Respimat had significantly better TST90 than did those using the HandiHaler. Sleep disturbance was highly variable in these patients, but the sleep stage durations were significantly better in the Respimat group. Sleeping SaO(2) can be improved by tiotropium delivered using either the HandiHaler device or the Respimat Soft Mist Inhaler. However, the patients who used the Respimat device had significantly better TST90 and sleep architecture parameters.