This study examines the risk for alcohol and other drug (AOD) problems resulting from alcohol plus marijuana use compared to alcohol-only use. Data are from telephone interviews with 1113 randomly selected college students attending two large urban universities in the southwestern United States. Alcohol and marijuana users (dual users) were more likely to be younger and report a higher mean number of drinks per occasion and experiencing all AOD problems studied compared to alcohol-only users. Multivariate logistic regression analysis findings reveal the relationship between dual-substance use and increased risk for AOD problems remained after controlling for demographics and alcohol use behaviors. Such problems include greater odds of legal problems and riding with or being an intoxicated driver. College students using alcohol and marijuana are at much higher risk for AOD problems than are students who use alcohol only, even when heavy drinking is taken into account.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.
"Previous studies have only examined differences in small networks (e.g., less than 10 alters); this is the first study to use a large network design. Although individuals who consume alcohol tend also to use marijuana and tobacco (Reboussin et al., 2006; Shillington & Clapp, 2006), this study empirically demonstrated for the first time that this populationlevel trend was also clearly observable within individuals' social networks . The frequency of alter drinking, smoking, and marijuana use was moderately to strongly correlated, suggesting either that egos perceived that alters tend to engage in multiple addictive behaviors or that alters actually tend to engage in multiple addictive behaviors. "
"One study found that students who reported past-year use of both marijuana and alcohol had lower grades, missed more classes, and reported more legal and interpersonal problems when compared with their peers who used only alcohol (Shillington & Clapp, 2006). In addition, the use of both alcohol and illicit drugs in adolescence is linked to greater risk for alcohol and other drug misuse in adulthood when compared with the use of only one of these substances (Shillington & Clapp, 2006; Stenbacka, 2003). Despite clear evidence for the presence of proximal problems (negative consequences, risk behaviors) associated with both heavy drinking and other drug use, it is important to elucidate the more global impact of drug use on students' lifestyle and functioning above and beyond heavy drinking. "
[Show abstract][Hide abstract] ABSTRACT: Objective:
Diminished availability of substance-free reinforcement is a behavioral economic risk factor for dependence. The goal of this study was to determine the incremental effects of increasing levels of substance use (heavy drinking [HD], heavy drinking and marijuana use [HD + MJ], and polysubstance use) on levels of reinforcement related to substance-free activities and related constructs among college students.
Participants were 205 college students (53% female; 65% White, 26% African American; Mage = 19.5 years) who reported at least one heavy drinking episode (five/four or more drinks on one occasion for a man/woman) in the past month. Participants reported on past-month illicit drug use and substance-free activity reinforcement, time allocation, and depression.
A series of analyses of covariance indicated that heavy drinking, marijuana use, and other illicit drug (polysubstance) use was associated with lower total and peer-related substance-free reinforcement; less time spent exercising, studying or completing homework, and participating in extracurricular activities; and greater depression compared with HD alone. Polysubstance use was also associated with lower peer-related substance-free reinforcement compared with HD + MJ. Furthermore, those who engaged in HD + MJ use allocated less time to exercise and studying/homework compared with HD-alone participants.
Illicit drug use is associated with incremental deficits in substance-free reinforcement above and beyond heavy drinking. In particular, students who use illicit drugs other than marijuana may be at high risk and require intervention approaches that explicitly increase engagement in developmentally important substance-free activities such as academics.
Journal of studies on alcohol and drugs 01/2015; 76(1):106-116. DOI:10.15288/jsad.76.1.106 · 2.76 Impact Factor
"Similarly, associations observed between transitioning to alcohol use and smoking marijuana were not unexpected. Simultaneous poly-substance use, or using more than one substance at once, is commonly reported with marijuana and alcohol  . "
[Show abstract][Hide abstract] ABSTRACT: Hepatitis C virus (HCV) screening can provide opportunities to reduce disease progression through counseling against alcohol use, but empirical data on this issue are sparse. We determined the efficacy of a behavioral intervention in reducing alcohol use among young, HCV-infected injection drug users (IDUs) (n=355) and assessed whether changes in liver enzymes were associated with changes in alcohol consumption.
Both the intervention and attention-control groups were counseled to avoid alcohol use, but the intervention group received enhanced counseling. Logistic regression, ANOVA, and continuous time Markov models were used to identify factors associated with alcohol use, changes in mean ALT and AST levels, and change in alcohol use post-intervention.
Six months post-intervention, alcohol abstinence increased 22.7% in both groups, with no difference by intervention arm. Transition from alcohol use to abstinence was associated with a decrease in liver enzymes, with a marginally greater decrease in the intervention group (p=0.05 for ALT; p=0.06 for AST). In multivariate Markov models, those who used marijuana transitioned from alcohol abstinence to consumption more rapidly than non-users (RR=3.11); those who were homeless transitioned more slowly to alcohol abstinence (RR=0.47); and those who had ever received a clinical diagnosis of liver disease transitioned more rapidly to abstinence (RR=1.88).
Although, behavioral counseling to reduce alcohol consumption among HCV-infected IDUs had a modest effect, reductions in alcohol consumption were associated with marked improvements in liver function. Interventions to reduce alcohol use among HCV-infected IDUs may benefit from being integrated into clinical care and monitoring of HCV infection.
Journal of Hepatology 11/2010; 55(1):45-52. DOI:10.1016/j.jhep.2010.10.028 · 11.34 Impact Factor