Study of Spectrum of Sleep Disorders in Patients with Chronic Obstructive Pulmonary Disease

Background and objectives: Quality of sleep is lower in chronic obstructive pulmonary disease (COPD) patients. Compared to patients who have only obstructive sleep apnea (OSA) when they sleep, COPD and OSA overlap are more likely to have poorer sleep quality and prolonged oxygen desaturation. Our study sought to determine whether patients with COPD had the sleep illness spectrum and to determine any association between OSA and the severity of COPD. Methods: Following a thorough history, clinical examination, X-ray chest, spirometry, and the collection of data such as neck circumferences, scoring of the International Restless Leg Syndrome (IRLS) rating, and an insomnia severity index (ISI), 100 patients with COPD were included. These patients underwent an overnight polysomnography (PSG) test to assess sleep variables. Results: Among the 100 patients included, 53 were male and 47 were female. In all the subjects included, nine patients were reported with very severe COPD, 28 with severe COPD, 57 with moderate COPD, and six with mild COPD. Patients with COPD exhibited reduced rapid eye movement (REM) sleep, with a mean REM sleep duration of 35.6 ± 23.7 minutes. The mean duration of nonrapid eye movement (NREM) sleep was 322.2 ± 87 minutes. The mean REM latency was prolonged at 156 ± 102.7 minutes. Sleep efficiency (SE) was reduced, averaging 71.98% ± 14.7%, accompanied by a prolonged mean sleep onset time of 26.9 ± 37.7 minutes. Subjects showed increased arousal activity, with a mean total arousal index of 23.3 ± 16.7 and a respiratory disturbance index (RDI) of 22.7 ± 22.7. The mean apnea-hypopnea index (AHI) was elevated at 22.6 ± 22.6, indicative of OSA in combination with COPD, suggesting an OSA-COPD overlap. Nocturnal desaturation was significant, with a mean REM oxygen saturation of 88.6 ± 7.1% and a lowest oxygen saturation of 71.4 ± 15.1%. Additionally, the mean insomnia severity score was 11.9 ± 6.1, and the restless leg syndrome (RLS) score averaged 10.7 ± 8.3. Both scores suggest a trend of coexisting insomnia and RLS among COPD patients. In our study, analysis suggested that factors such as REM duration, stage II and stage III sleep, SE, AHI, RDI, lowest O2 saturation, insomnia severity, and the International Restless Legs Syndrome Study Group (IRLSSG) severity are significantly related to the severity of COPD. Conclusion: Chronic obstructive pulmonary disease patients are likely to have disturbed sleep patterns, making it essential to assess the overlap between COPD and OSA. The outcome of the present research would help in reducing the mortality rate and developing a strategy to mitigate the adverse effects of the occurrence of OSA in COPD patients. To improve the health outcomes of COPD patients with concurrent sleep problems, it would be helpful to personalize therapeutic methods by concentrating on particular treatment options for both sleep quality and the severity of COPD.