Cannabis Use Negatively Impacts Other Health Behavior Changes Among Reproductive Age Women

Background and Purpose: Negative health behaviors rarely occur in isolation, and research is moving to the study of interventions addressing multiple health behavior changes in order to maximize impact. Growing evidence indicates that changes in one targeted health behavior increases the likelihood of changing other similar or related behaviors. Little is known, however, about how the presence of an untargeted health risk behavior might impact the change of targeted behaviors. As cannabis has become the most commonly used addictive drug after tobacco and alcohol in the US, and 1 in 10 US women of reproductive age (18–44 years) reported current cannabis use in 2016, this study focused on examining the impact of cannabis use as an untargeted behavior on reducing risk level alcohol consumption (>3 drinks/day and/or >7 drinks/week) and use of effective contraception (targeted behaviors) in women at risk of an alcohol-exposed pregnancy (AEP).

Methods: This study used data from CHOICES Plus, a two-group randomized control trial designed to test a preconception intervention aimed at reducing the risk of alcohol- and tobacco-exposed pregnancy in women. Participants were 18-44, drinking at risk levels, sexually active, fertile, and not using effective contraception.

The CHOICES Plus intervention consists of two visits with a behavioral health specialist trained in the Transtheoretical Model, Motivational Interviewing, and the CHOICES Plus intervention protocol. Women were recruited from 12 primary care clinics in a large Texas public healthcare system. We used logistic regression to examine the difference between cannabis users and non-users in those women who received the CHOICES Plus intervention. Target outcomes were reduced risk of AEP, reduced risk drinking, and use of effective contraception at 9 month follow-up. Alcohol use, sexual intercourse, and contraception were measured using the Timeline FollowBack Calendar.

Results: Of the women who received the CHOICES Plus intervention (n=105), those who continued to use cannabis at 9 months were less likely to reduce their risk of AEP (46.7% of the cannabis users versus 73.3% of the non-users were at reduced risk; OR 3.143; p=.007), less likely to reduce risk level drinking (25.9% of the cannabis users versus 50.0% of the non-users; OR 2.867; p=.013), and less likely to use effective contraception (33.3% of the cannabis users versus 60.0% of the non-users, OR 3.000; p=.007) at 9 months.

Conclusion and Implications: Women who continued to use cannabis through the outcome period in CHOICES Plus had overall poorer outcomes. It is possible that the use of cannabis interfered with the effectiveness of the intervention. Clinicians need to be aware of the negative influence that cannabis use, as an untargeted risk heath behavior, may have on the probability of positive change in targeted health risk behaviors. More research addressing multiple risk behaviors simultaneously is needed, particularly when cannabis use is prevalent in the study population.