Obstructive sleep apnea is highly prevalent in COVID19 related moderate to severe ARDS survivors: findings of level I polysomnography in a tertiary care hospital.

STUDY OBJECTIVES: Studies have found Obstructive Sleep Apnea (OSA) as a risk factor for increased risk for COVID19 Acute respiratory Distress Syndrome (ARDS); but most of the studies were done in already known patients of OSA. This study was done to find prevalence of OSA in patients with COVID-19 related acute respiratory distress syndrome. METHODOLOGY: A hospital based longitudinal study was conducted among COVID 19 Intensive Care Unit (ICU) survivors. All consecutive COVID19 with moderate to severe ARDS were evaluated for OSA by Level I Polysomnography (PSG) after 4-6 weeks of discharge. Prevalence of OSA and PSG variables {Total sleep time, Sleep efficiency, sleep stage percentage, Apnea Hypopnea Index (AHI), T90, nadir oxygen} was estimated. RESULTS: Out of 103 patients discharged from ICU during study period (October 2020 to 15 December 2020), 67 underwent Level I PSG. Mean Age was 52.6 ± 10.9 years and mean Body Mass Index was 27.5 ± 6.2 kg/m2. Total sleep time was 343.2 ± 86 min, sleep efficiency was 75.9 ± 14.2%. OSA (AHI ≥5) was seen in 65/67 patients and 49 patients had moderate to severe OSA (ie AHI ≥15). CONCLUSION: Moderate-severe OSA was highly prevalent (73%) in COVID19 moderate to severe ARDS survivors. Role of OSA in pathophysiology of COVID19 ARDS needs further evaluation.

Sleep EEG Signatures in COVID-19 Survivors.

Study Objectives: Effect of COVID-19 on sleep architecture is not known. This study was done to find out EEG changes seen during sleep in COVID-19 survivors. Methodology: In this prospective single centre study, consecutive patients diagnosed with RTPCR confirmed COVID 19 were included after 4-6 weeks of discharge from hospital. All patients underwent level I PSG. EEG was analysed for presence of abnormal EEG pattern. Results: Total 189 patients were contacted telephonically for participation in this study. Finally 81 patients (55 males, 26 females) underwent Level I PSG. Total sleep time was 345.1 ± 85.1 min. Sleep efficiency was 76.0 ± 14.2%. Mean time (%) during N1, N2, N3 and Rapid Eye movement (REM) was 16.4%, 59.2%, 7.9% and 18.4% percentage, respectively. Mean AHI was 28.7 ± 22.8 per hour and arousal index was 23.9 ± 13.3. Alpha intrusion was the most common EEG finding (78%), followed by cyclical alternating pattern (59%). REM density was significantly increased in 38% of patients. REM alpha bursts and increased spindles were also seen in 27% and 16%. Conclusion: Abnormal EEG waves are very commonly seen in COVID-19 survivors. Presence of these abnormal PSG-EEG waves hints that COVID-19 might have similar effects as depression, insomnia on these subjects, at least in short run. Whether these changes are temporary or permanent needs to be evaluated by performing serial polysomnographies in patients with COVID-19 ARDS.