O059 Opioid-related central sleep apnea doesn’t harm respiratory and sleep parameters

Abstract Introduction Opioid-related central sleep apnea (CSA) is increasingly common, but its clinical implications are poorly understood. We analysed the “OpSafe” cohort, a large prospective multicentre study of chronic opioid users, to investigate whether opioid-related CSA worsens key respiratory and sleep outcomes. Methods Participants were chronic opioid users recruited from five pain clinics. They were measured daytime oxygen saturation (SpO2) and Epworth Sleepiness Scale (ESS), followed by in-lab polysomnography. Results A total of 160 participants were divided into three groups: 21 CSA, 66 obstructive sleep apnea (OSA), and 73 no-apnea. CSA participants had ~4 times higher opioid dose and exhibited a ~ 3% lower daytime SpO2 than OSA and no apnea participants. However, during sleep, oxygenation measures were similar between CSA and OSA groups. Compared daytime SpO2 to sleep mean SpO2, OSA decreased significantly (95.1 ± 1.9 vs 93.9 ± 2.1, p=.001), no-apnea moderately dropped (95.9 ± 1.9 vs 95.1 ± 2, p=.05), whereas CSA participants had no change (92.9 ± 3.4 vs 93.5 ± 2, p=.66). CSA event duration was shorter than that of OSA. Sleep architecture and arousal indices in CSA patients were normal except for a reduced REM sleep linked to higher opioid doses. Abnormalities in quantitative EEG power only occurred during REM sleep while CSA was rare. Furthermore, CSA was not a significant predictor of daytime sleepiness, explaining only 1.5% of the variance of ESS. Discussion Our novel findings showed that opioid-related CSA did not worsen key respiratory and sleep outcomes. While it is essential to alleviate respiratory depression, targeted therapies to reduce opioid-related CSA may be unnecessary.