Cannabis use during alcohol treatment is associated with alcohol-related problems one-year post-treatment

Abstract

Background: Prior research shows that cannabis use during treatment for Alcohol Use Disorders (AUD) is related to fewer abstinent days from alcohol, although only among those who use cannabis 1–2x/month. Here we extend prior research by assessing the relationship between the frequency of cannabis use during AUD treatment and post-treatment alcohol-related consequences. Methods: Data come from the Combined Pharmacotherapies and Behavioral Interventions (COMBINE) Study, a large US randomized control trial of treatments for AUD. The current analyses include 206 cannabis users and 999 cannabis abstainers and compare longitudinal drinking data between those who used cannabis versus those who abstained during COMBINE treatment. The primary exposure was quartiles of cannabis use (Q1: less than 1x/month during treatment, Q2: 1–2x/month, Q3: 4–8x/month, Q4: 12x/month or more), with cannabis abstainers as the reference group. Outcomes were alcohol-related problems at the end of treatment and one-year post-treatment as measured by the Drinker Inventory Consequences. Results: Compared to cannabis abstinence, the most frequent use during treatment was related to 1.44 times as many physical consequences one-year post-treatment. Cannabis use was not related to physical consequences immediately after treatment, or to intrapersonal, interpersonal, social responsibility or impulse control problems at either post-treatment time point. Conclusions: In a sample of individuals in treatment for AUD, using cannabis 12x/month or more during treatment is associated with increased rates of physical consequences attributed to alcohol use. Individuals in treatment for AUD who also use cannabis might benefit from reducing or stopping cannabis use to avoid alcohol-related physical problems.

Effects of cannabis use on alcohol consumption in a sample of treatment‐engaged heavy drinkers in Colorado

“…Notably, in contrast to some prior work suggesting a detrimental effect of cannabis on drinking outcomes [2,27,36], both the infrequent and frequent cannabis use group in this study consumed 28% fewer drinks on days when cannabis was used. Conversely, one recent study suggested that, among individuals engaged in alcohol treatment who also use cannabis, those who used cannabis once or twice per month had fewer alcohol-abstinent days at the end of treatment, whereas for those who used more frequently, cannabis was not associated with increased alcohol use during treatment compared to cannabis abstainers [10].…”

Patterns of Cannabis and Alcohol Co-Use: Substitution Versus Complementary Effects

“… 17 Secondary analyses of the Combined Pharmacotherapies and Behavioral Interventions (COMBINE) Study data were conducted to examine the effects of cannabis use on drinking and on alcohol-related consequences 1 year posttreatment. 18 , 19 In support of the complementary hypothesis, any cannabis use relative to nonuse during treatment was associated with fewer abstinent days at the end of treatment. However, a nuanced association was uncovered such that those who used cannabis once or twice per month had significantly fewer alcohol-abstinent days after treatment.…”

“…More frequent cannabis use during AUD treatment in Project COMBINE also was associated with increased alcohol-related physical consequences 1 year after treatment. 19 Similarly, another secondary analysis of the U.S. National Alcohol Survey data from the general population subsamples of individuals previously treated for AUD showed that mid-level use (use of cannabis more than monthly but less than weekly) was associated with drinking more frequently, having more drinks per drinking occasion, and being more likely to experience alcohol-related harms relative to abstainers. 20 Together, these studies suggest that cannabis use may be complementary to alcohol use among individuals who have received treatment for AUD, although perhaps only at certain frequencies of use.…”

The Effects of Marijuana Use on Transitions through Stages of Alcohol Involvement for Men and Women in the NESARC I and II

“…This sex difference may be related to evidence that comorbidity is more common among women than men (Kessler et al, 1997), which may impact recovery, or biologic differences between men and women in the neurocircuits involved in addiction that impact recovery (Arain et al, 2013). Future research should assess the extent to which women may be substituting marijuana for alcohol to reduce drinking and aid in recovery (Subbaraman, 2014), even though research has not supported the effectiveness of this substitution (Subbaraman et al, 2018).…”

“…In addition, we need to understand whether marijuana use impacts not only the potential progression of problematic drinking, but also whether it effects the remission of alcohol problems. Subbaraman et al (2018) offer evidence that marijuana use may impede recovery from alcohol problems among those in a treatment program. Pacula et al (2008) found that comorbid use of marijuana and alcohol was associated with more costly and longer alcohol use disorder treatment.…”