TY - JOUR T1 - P039 REM sleep and dream reports in frequent cannabis versus non-cannabis users JF - BMJ Open Respiratory Research JO - BMJ Open Resp Res SP - A23 LP - A23 DO - 10.1136/bmjresp-2019-bssconf.39 VL - 6 IS - Suppl 1 AU - Ceri Bradshaw AU - Rebecca Borcsok AU - Matthew Taylor AU - Sophie Segust AU - Daniel Ford AU - Michelle Carr Y1 - 2019/11/01 UR - http://bmjopenrespres.bmj.com/content/6/Suppl_1/A23.1.abstract N2 - Tetrahydrocannabinidiol (THC; one of the main psychoactive components of cannabis) has been shown to suppress REM sleep1-4 and affect sleep latency,4 5 although these findings are not consistently replicated.3 4 6 Cannabis use is also reported to affect dreaming frequency.7 Most studies investigating cannabis use and sleep have been laboratory-based, while only a limited body of research exists on dream occurrence and cannabis use. This study aimed to pilot the measurement of participants sleeping at home in their usual surroundings, in order to assess effects of cannabis use compared to non-use, on objective sleep measures, dream reports, and self-reported anxiety, memory, and sleep quality. Eleven frequent cannabis users versus 8 non-users proceeded in their usual routines, and wore Hypnodyne Zmax portable sleep acquisition headbands (recording EEG, EOG and EMG) while sleeping at home over two consecutive nights. Participants gave dream reports in three awakenings, set at two-hourly intervals on each night, and once upon morning awakening, reporting dream content and subjective ratings of the dream’s bizarreness, emotionality, and sensory experience. In addition, participants completed problem cannabis use, lifetime and nightly cannabis use, PSQI, everyday memory and trait anxiety measures. No differences were reported by participants in sleep quality, anxiety or memory between the two groups; predictably, cannabis users reported significantly more problems in relation to use of the drug. Cannabis users demonstrated significantly longer sleep latency and less REM sleep overall; no other differences occurred in objective sleep measures between groups. Cannabis users reported higher bizarreness in their dreams, but no differences were reported in dream recall or other dream measures. It is noted that small sample sizes limit the generality of findings in this study. The procedure provides a useful paradigm and encouraging initial results, however, for contemporary research related to cannabis use and sleep in naturalistic conditions, in this ongoing project.ReferencesBabson K A, Sottile J, Morabito D. Cannabis, cannabinoids, and sleep: a review of the literature. Current psychiatry reports 2017;19(4):23.Bonn-Miller MO, Babson KA, Vandrey R. Using cannabis to help you sleep: heightened frequency of medical cannabis use among those with PTSD. Drug and alcohol dependence 2014;136:162–165.Bowles N P, Herzig M X, Shea S A. Recent legalisation of cannabis use: effects on sleep, health, and workplace safety. Nature and Science of Sleep 2017;19(9):249–51Feinberg I, Jones R, Walker J M, Cavness C, March J. Effects of high dosage delta-9-tetrahydrocannabinol on sleep patterns in man. Clinical Pharmacology Therapy 1975;17(4):458–66.Karacan I, Fernández-Salas A, Coggins W J, Carter W E, Williams R L, Thornby J I, Villaume J P. Sleep electroencephalographic-electrooculographic characteristics of chronic marijuana users: Part I. Annals of the New York Academy of Sciences 1976;282(1):348–74.Schierenbeck T, Riemann D, Berger M, Hornyak M. Effect of illicit recreational drugs upon sleep: cocaine, ecstasy and marijuana. Sleep Medicine Reviews 2008;12(5):381–389.Tassinari CA, Ambrosetto G, Peraita-Adrado MR, Gastaut H. The neuropsychiatric syndrome of δ9-tetrahydrocannabinol and cannabis intoxication in naïve subjects. In: Nahas G G, Sutin K M, Harvey D, Agurell S, Pace N, Cancro R. (Eds), Marihuana and Medicine 1999 (1st edition 649–664). ER -