Background: Pain and sleep disturbances are primary reasons for medicinal cannabis use. Cannabis influences both pain and sleep through its modulation of the endocannabinoid system, which regulate pain pathways and sleep regulation. Despite their interconnected roles, the effects of cannabis and chronic pain on sleep architecture are studied mainly in isolation. An integrated understanding is needed to guide use and minimize risks in this population. Objective: Our primary aim was to examine the potential interactive effect of regular cannabis use on chronic pain and sleep. Methods: A total of 339 nights (2,273.43 hours) of in-home sleep electroencephalogram (EEG) recordings were collected from 60 adults (50% male; 32% chronic pain; 47% cannabis use; Mage= 25.25; SE= 1.05) over seven consecutive nights per participant. A mixed-model repeated- measures ANCOVA tested the main effects and interactions of chronic pain and regular cannabis use on total sleep time (TST), total slow-wave sleep (SWS%), total rapid-eye-movement (REM%), sleep onset latency (SOL), and number of awakenings. Results: There was a significant main effect of cannabis use on SWS, TST, SOL, and REM. There was a significant main effect of chronic pain on TST. Significant interactions emerged between cannabis use and chronic pain on SWS and REM. Conclusions: These findings may reflect a dysregulated sleep response in individuals using cannabis to manage chronic pain, highlighting the need to consider both beneficial and detrimental effects of cannabis on specific sleep stages. Keywords: N3, slow-wave sleep, pain, cannabis, EEG

The authors have declared no competing interest.

This study did not receive any funding

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The Institutional Review Board of the University of Texas at Dallas approved this study.

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