The influence of acute morphine use on obstructive sleep apnea: A systematic review and meta-analysis

The present study was conducted to systematically evaluate the acute effect of morphine on obstructive sleep apnea (OSA). The PubMed, Embase, Cochrane Library, Clinicaltrials.gov, China National Knowledge Infrastructure (CNKI), and Wan-Fang databases were searched for randomised controlled trials studying the influence of morphine on OSA published up to May 24, 2021. The Cochrane risk of bias tool was used to assess study quality and meta-analysis was performed on the included clinical trial results to quantify the impact of morphine on various sleep and respiratory parameters. Three studies (n = 132 patients) were ultimately examined. There were no significant differences between patients with OSA taking morphine and placebo/non-opioids with respect to the sleep Apnea-Hypopnea Index (mean difference [MD] 1.78, 95% confidence interval [CI] -2.41, 5.98; p > 0.05); Oxygen Desaturation Index (MD 1.49, 95% CI -3.21, 6.19; p > 0.05); Obstructive Sleep Apnea Index (MD 0.83, 95% CI -2.08, 3.75; p > 0.05); Hypopnea Index (MD -0.01, 95% CI -2.64, 2.63; p > 0.05); lowest oxygen saturation (MD 0.68, 95% CI -4.50, 5.86; p > 0.05); or sleep oxygen saturation >90% (MD 0.10, 95% CI -1.14, 1.34; p > 0.05). In conclusion, a single dose of 30 or 40 mg morphine does not have a significant effect on sleep or respiratory outcomes compared to placebo in patients with OSA, challenging the orthodoxy that opioids worsen OSA.