Effect of ipratropium bromide treatment on oxygen saturation and sleep quality in COPD

Study objectives: Patients with COPD are at risk of experiencing a deterioration in arterial oxygen saturation (SaO₂) during sleep, which is generally most pronounced during rapid eye movement (REM) sleep. Increased cholinergic tone has been suggested as a contributing factor to this decrease in SaO₂. Therefore, we investigated whether 4-week treatment with ipratropium bromide inhalation solution 0.02% (qid) could improve sleep characteristics in COPD. Design: Randomized, placebo-controlled, double- blind, two-arm parallel study of 4 weeks of treatment with ipratropium bromide solution or placebo. Setting: Multicenter investigation. Patients: Thirty-six patients with moderate-to-severe COPD (FEV₁ < 65% of predicted). Measurements and results: Evaluation included polysomnographic, pulmonary function, and subjective quality of sleep (visual analog scale [VAS]) assessments. It was found that 4 week of treatment with ipratropium bromide solution in patients with COPD led to the following: (1) a significant (p = 0.05) improvement in mean nocturnal SaO₂ with the more severe the nocturnal desaturation, the greater the improvement in SaO₂; (2) significant (p = 0.03) improvement in perceived sleep quality (VAS: 5.5 ± 0.5 after placebo; 7.2 ± 0.5 after ipratropium); (3) a significant (p = 0.05) increase in REM sleep time (48.6 ± 6.3 min after placebo; 66.5 ± 6.4 min after ipratropium) with no effect on other sleep stages or to sleep time; and (4) a significant (p = 0.01) increase in pre-sleep FVC and flow rate at 50% of the vital capacity. Conclusions: These findings demonstrate that ipratropium bromide therapy can improve sleep SaO₂ as well as sleep quality in patients with moderate-to-severe COPD.