Preliminary research into cannabis and insomnia suggests that cannabidiol (CBD) may have therapeutic potential for the treatment of insomnia. Delta-9 tetrahydrocannabinol (THC) may decrease sleep latency but could impair sleep quality long-term. Novel studies investigating cannabinoids and obstructive sleep apnea suggest that synthetic cannabinoids such as nabilone and dronabinol may have short-term benefit for sleep apnea due to their modulatory effects on serotonin-mediated apneas. CBD may hold promise for REM sleep behavior disorder and excessive daytime sleepiness, while nabilone may reduce nightmares associated with PTSD and may improve sleep among patients with chronic pain. Research on cannabis and sleep is in its infancy and has yielded mixed results. Additional controlled and longitudinal research is critical to advance our understanding of research and clinical implications.

The current review critically examines the extant empirical literature focused on the associations among cigarette smoking, trauma, and posttraumatic stress. Inspection of the extant literature suggests smoking rates are significantly higher among persons exposed to a traumatic event relative to those without such exposure. Moreover, smoking rates appear particularly high among persons with posttraumatic stress disorder (PTSD). In terms of the direction of this relation, evidence most clearly suggests posttraumatic stress is involved in the development of smoking. Significantly less is known about the role of trauma and PTSD in terms of cessation outcome. Limitations of extant work, clinical implications, and key directions for future study are delineated. Keywordssmoking; posttraumatic stress; comorbidity; trauma; PTSD Cigarette smoking continues to be one of the leading preventable causes of death and disease in the U.S., resulting in healthcare costs that rank among the highest in the country [U.S. Department of Health and Human Services (USDHHS), 2004]. Large-scale efforts targeting smoking cessation have helped address this problem (USDHHS, 2000), but the negative impact of smoking is still widely evident. For example, more than 1 in 5 (22%) adults [Centers for Disease Control and Prevention (CDC), 2004] and almost 1 in 4 (24%) youth (Johnston, O'Malley, Bachman, & Schulenberg, 2004) in the U.S. currently smoke. Moreover, though smokers often are motivated to quit, the majority (approximately 90-95% of self-quitters and 60-80% of those in treatment programs) relapse (Cohen et al., 1989). Scholars have suggested smokers who fail at quitting may have unique attributes that increase their probability of smoking (Hughes, 1993;Pomerleau, 1997). Although various characteristics may increase the risk of relapse (e.g., heavier smoking levels), psychological disorders and related vulnerability factors have increasingly been recognized as playing a prominent role in quit success (Hughes, 1993;Zvolensky & Bernstein, 2005; Zvolensky, Bernstein, Marshall, & Feldner, in press).Smokers with anxiety disorders represent a common, albeit understudied, segment of the smoking population who are at heightened risk for relapse . For example, Correspondence concerning this article should be addressed to Dr. Matthew T. Feldner, Intervention Sciences Laboratory, University of Arkansas, Department of Psychology, 216 Memorial Hall, Fayetteville, AR 72701, 479-575-4256 (phone), 479-575-3219 (facsimile). Electronic mail may be sent to mfeldne@uark.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the jo...

There has been growing interest in the interrelations among traumatic event exposure, posttraumatic stress disorder (PTSD), and sleep problems. A wealth of research has examined the associations among these factors and there is an emerging literature focused on how sleep problems relate to both traumatic event exposure and PTSD across time. The current review provides a detailed analysis of studies pertaining to the temporal patterning of sleep problems and traumatic event-related factors (e.g., traumatic event exposure, PTSD) and draws conclusions regarding the current state of this literature. Research coalesces to suggest (1) exposure to a traumatic event can interfere with sleep, (2) PTSD is related to the development of self-reported sleep problems, but evidence is less clear regarding objective indices of sleep, and (3) limited evidence suggests sleep problems may interfere with recovery from elevated posttraumatic stress levels. Future research now needs to focus on understanding mechanisms involved in these patterns to inform the prevention and treatment of comorbid sleep problems and PTSD.

Results are discussed in terms of future directions for research given the current debates regarding legalization of cannabis for medical purposes and, more generally, the lack of empirical data to inform such debates.