Cannabis use is increasingly common in the United States (US) and is associated with adverse outcomes across a range of domains. Following a 5-year period of relative stability from 2002 through 2006, the prevalence and absolute number of individuals who regularly use cannabis have increased steadily (Hasin and Walsh, 2021, Substance Abuse and Mental Health Services Administration, 2021). Individuals who use cannabis are at increased risk of negative health outcomes, including poor work performance, other substance misuse, HIV risk behaviors, neurocognitive problems, interpersonal violence, and increased risk of psychosis (Adefuye et al., 2009, Brodbeck et al., 2006, Brook et al., 2008, Buckner et al., 2011, Conroy et al., 2015, D'Souza, 2007, Gruber et al., 2003, Moore et al., 2005, Naar-King et al., 2010, Stinson et al., 2006). Despite substantial increases in cannabis use and associated impairments, only a small percentage of individuals seek treatment for cannabis-related problems in a given year; thus, creative strategies are needed to help these individuals modify their cannabis use (Hedden and Gfroerer, 2011).

Nationally representative surveys in the US indicate that sleep problems are common among individuals with regular cannabis use, with nearly half of those reporting past-month cannabis use also reporting concurrent “trouble with sleep” (Diep et al., 2021). In a cohort study of 800 adults seeking medical cannabis certification in Michigan, we found that insomnia was one of the most common co-occurring problems, with 80 % of the cohort reporting cannabis use specifically for insomnia in the past month (Cranford et al., 2017). Among these respondents, more than half reported difficulties falling asleep (53 %) or staying asleep (54 %) at least twice weekly despite cannabis use for sleep; 25 % of these individuals reported insomnia symptoms almost nightly. Additionally, nearly two-thirds of respondents reported a worsening of insomnia during the previous 2 weeks as a result of cannabis withdrawal (Cranford et al., 2017). Finally, we found that higher motivation to use cannabis for insomnia was uniquely associated with greater frequency of cannabis use, as well as poorer physical and mental health functioning (Bohnert et al., 2018). These findings are in line with other studies indicating that poor sleep is linked to the initiation (Roane and Taylor, 2008, Taylor and Bramoweth, 2010) and increased use of cannabis (Budney and Moore, 2002, Budney et al., 2008, Vandrey et al., 2011) and that insomnia is a barrier to cannabis use reduction or discontinuation among those with regular cannabis use (Babson et al., 2013a, Babson et al., 2013b).

Given its high co-occurrence and associations with adverse outcomes among individuals with regular cannabis use, insomnia may be a target for reducing cannabis use and improving functioning. Although hypnotic medications are the most widely used treatments for insomnia, non-pharmacological approaches are generally preferred for individuals who use substances (Miller et al., 2017). Cognitive behavioral therapy for chronic insomnia (CBTi) is a multicomponent intervention that targets behavioral and cognitive factors that contribute to chronic sleep disturbances. Multiple controlled trials indicate that CBTi benefits 70–80 % of individuals with chronic insomnia with and without co-occurring health conditions (Morin et al., 1994, Murtagh and Greenwood, 1995, Smith et al., 2002, Wu et al., 2015), nearly 50 % achieve remission from insomnia post-treatment (Buysse et al., 2011, Morin et al., 2009), and initial treatment gains are well-maintained over time, with follow-up periods as long as 2–3 years (Backhaus et al., 2001, Morin et al., 1999).

Despite its demonstrated efficacy, only three trials to date have examined the effects of CBTi on sleep and cannabis use among individuals who regularly use cannabis. Pilot data from a small two-week study indicated that CBTi delivered via a telephone app (CBTi Coach) reduced self-reported cannabis use and improved sleep efficiency more than a mood-tracking app in four military veterans attempting to discontinue cannabis use (Babson et al., 2015). More recently, Short et al. (2021) compared brief behavioral treatment for insomnia (BBTi, a shorter modified version of CBTi containing only behavioral strategies) to a wait list control in 56 trauma-exposed young adults with elevated insomnia symptoms (Insomnia Severity Index [ISI] score >8) and at least weekly cannabis use. The results indicated that insomnia symptoms and cannabis-related problems improved more in BBTi compared to wait-list participants at post-treatment and 3-month follow-up, but there were no group differences in mean daily cannabis use. Attrition was also high, with fewer than 50 % of BBTi participants completing post-treatment (13/28) and follow-up (10/28) assessments. Finally, in an uncontrolled study of 19 individuals with cannabis use disorder and insomnia, Geagea et al. (Geagea et al., 2022) reported that insomnia improved from moderately to mildly severe after four sessions of CBTi, with further improvement at 3- and 6-month follow-up. In addition, 66 % of participants reported reduced cannabis use at 6 months compared to baseline and nearly half of participants attributed this reduction to improvements in their sleep (Geagea et al., 2022). Despite the potential promise of these preliminary studies, controlled studies with larger sample sizes are needed to evaluate the effects of insomnia treatment on sleep and cannabis use.

The primary objectives of this clinical trial development project were to pilot the study methods and evaluate the preliminary efficacy of a telemedicine-delivered CBTi tailored for adults using cannabis for insomnia (CBTi-CB-TM) compared to a telemedicine-delivered Sleep Hygiene Education (SHE-TM) for improving insomnia and reducing cannabis use. A secondary objective was to compare the effects of the two conditions on daytime functioning and measures of treatment credibility and therapeutic alliance. Our main hypothesis was that insomnia severity, as measured by the Insomnia Severity Index, would improve more and frequency of cannabis use, as measured by the TimeLine Follow Back (TLFB), would reduce more in CBTi-CB-TM participants at post-treatment and 8-week follow-up. We further hypothesized that daytime functioning would improve more in CBTi-CB-TM participants and that treatment credibility and therapeutic alliance would not be different between CBTi-CB-TM and SHE-TM conditions.