Prevalence of Sleep Related Breathing Disorders (SRBD) and the Assessment of Quality of Sleep Among Patients with Chronic Obstructive Pulmonary Disease (COPD): An Analytical Cross-Sectional Study

Background: Sleep disturbances are common in chronic obstructive pulmonary disease (COPD) and may result from sleep-related breathing disorders (SRBD), nocturnal hypoxemia, and ventilatory insufficiency. Indian data on SRBD and sleep quality in severe COPD, especially among patients with chronic hypercapnic respiratory failure, are limited. Objectives: To estimate the prevalence and risk factors of SRBD in COPD, assess sleep quality, and compare sleep parameters between COPD patients with and without chronic hypercapnic respiratory failure. Methods: This analytical cross-sectional study was conducted at GDMCH, Dharmapuri (2023–2024). Forty-five patients with severe stable COPD (post-bronchodilator FEV₁ <40%) without exacerbation for ≥4 weeks were enrolled. Demographic and clinical details, anthropometry, spirometry, arterial blood gas (ABG), laboratory parameters, Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and full attended polysomnography were performed. Patients were grouped as COPD with chronic hypercapnic respiratory failure (Group A) and without respiratory failure (Group B). Results: The mean age was 57.38 ± 7.48 years and 82.2% were males. SRBD prevalence was low, with obstructive sleep apnea in 6.67% (mean AHI 3.33 ± 3.75). Poor sleep quality was common (PSQI 10.07 ± 3.52) with excessive daytime sleepiness (ESS 11.93 ± 5.34). Polysomnography revealed reduced sleep efficiency (64.15 ± 9.10%), shortened total sleep time (264.71 ± 51.68 min), and elevated arousal index (25.39 ± 7.74/h). Group A (n=32) had significantly worse ABG parameters and poorer sleep indices and nocturnal oxygenation than Group B (n=13). Conclusion: Sleep impairment is highly prevalent in severe COPD, particularly with chronic hypercapnic respiratory failure, even when SRBD prevalence is low. Routine evaluation of sleep quality and nocturnal oxygenation may improve COPD care.