Gender differences in the developmental risk of onset of alcohol, nicotine, and marijuana use and the effects of nicotine and marijuana use on alcohol outcomes

Investigating the associations of age of initiation and other psychosocial factors of singular alcohol, tobacco and marijuana usage on polysubstance use: analysis of a population-based survey in Jamaica

OBJECTIVES

This study aimed to examine concurrent polysubstance use of alcohol, tobacco and marijuana and determine correlations with access to marijuana, friend and familial drug use habits, risk perception and the age of initiation associated with the singular use of these substances.

DESIGN

A secondary data analysis.

SETTING

Used the Jamaica National Drug Prevalence Survey 2016 dataset.

PARTICIPANTS

Involved the entire dataset comprising 4623 randomly selected respondents between 12 and 65 years old.

OUTCOME MEASURES

Primary outcome: concurrent polysubstance use recorded as using two or more of alcohol, tobacco and marijuana. Predictor variables include risk perception and age of initiation of singular alcohol, tobacco and marijuana use, ease of marijuana access and family and friend alcohol and illegal drug use.

RESULTS

Approximately 58%-66% of respondents commenced singular alcohol, tobacco or marijuana use under 17. Participants commencing marijuana use at 11 years and under and between 12 and 17 were 3.346 and 4.560 times more likely to report past month concurrent polysubstance use (p=0.030 and p<0.001). Respondents who did not believe that smoking tobacco sometimes (p=0.049), and smoking marijuana sometimes and often was harmful, had increased odds of concurrent polysubstance use (p=0.047 and p<0.001, respectively). Respondents who indicated access to marijuana as easy were significantly more likely to report past month concurrent polysubstance use compared with those who reported access as difficult (p=0.002). Participants who indicated that friends or family members get drunk and take illegal drugs were associated with 1.722 and 1.864 increased odds of reporting past month concurrent polysubstance use (p=0.004 and p=0.017, respectively).

CONCLUSIONS

Decreased perceived risk, childhood and adolescent age of initiation and easy access to marijuana were significantly associated with polysubstance use among Jamaicans. The influence of friends and family members' drug and alcohol use behaviours on individuals developing polysubstance use habits further endorses the need for interventions.

Effect of very low nicotine content cigarettes on alcohol drinking and smoking among adult smokers who are at-risk alcohol drinkers

Alcohol and tobacco use are interrelated. This study examined response to very low nicotine content (VLNC) and moderate nicotine content (MNC) cigarettes by problematic drinking. We utilized a double-blind, randomized, within-subjects crossover design of VLNC and MNC cigarettes in two groups of adult cigarette smokers: with at-risk drinking (ARD; n = 23) and without ARD (n = 24). Participants smoked only their assigned experimental cigarette in their home environment for 7 days, and completed laboratory visits, including ad libitum smoking of the assigned experimental cigarette, at the beginning and end of each experimental week. Participants smoked their usual cigarettes for 7 days between conditions. Participants provided daily reports of alcohol and cigarette consumption. Current Diagnostic and Statistical Manual of Mental Disorders-5th edition (DSM-5) alcohol use disorder (AUD) was assessed at baseline and the end of each experimental week. Compliance with smoking of experimental cigarettes was good. Adjusting for baseline drinking, there was no significant effect of experimental cigarette or ARD group on drinks per day or alcohol urges. There was no effect of experimental cigarette or ARD group on cigarettes per day, or on any puff topography outcome or postsmoking exhaled carbon monoxide during laboratory smoking. No participant had a change in AUD status or AUD severity. After 7 days of exposure to VLNC cigarettes, adult cigarette smokers with ARD did not show compensatory drinking or compensatory smoking behavior. A future policy change in the United States to reduce nicotine content in cigarettes may not produce unintended compensatory drinking or smoking among this vulnerable and prevalent population of smokers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Alcohol, cannabis, and tobacco polysubstance use: A latent profile analysis of age of onset

BACKGROUND

Despite understanding the long-term risks associated with early substance use, less is known about the specific patterns of the age of onset (AO) across multiple substances and whether these patterns of early exposure are linked to substance use later in young adulthood. Consequently, the present study sought to (1) identify distinct classes regarding AO for alcohol, cannabis, and tobacco and (2) compare these classes on patterns of individual and simultaneous alcohol, cannabis, and tobacco use, other substance use, and mental health symptoms.

METHODS

Participants were 510 emerging adults (Mage = 21.35; 88.6% men) who reported past-year use of alcohol, cannabis, and tobacco.

RESULTS

Latent profile analysis was used to identify classes based on three indicators: AO for alcohol, cannabis, and tobacco. Results revealed that four classes best fit the data: Earliest AO for Alcohol (19.8%); Latest AO for Substances (6.5%); Late AO for Substances (67.8%); Earliest AO for Cannabis and Tobacco (5.9%). Classes varied on current patterns of individual substance use, co-use of substances, other illicit drug use, and mental health symptomology. The Latest AO of Substances class reported the lowest alcohol use, cannabis use, other illicit drug use, and mental health symptomology than the other classes. The Earliest AO for Alcohol and the Late AO of Substances reported a lower frequency of tobacco compared to the other classes. The Late AO of Substance class reported the highest past-year frequency of simultaneous alcohol and cannabis use.

CONCLUSIONS

The current study contributed to the larger polysubstance literature by identifying profiles that may signify risky patterns of use. Findings may help guide prevention and intervention work with adolescents and young adults.

Perceived neighborhood disorder and frequency of marijuana use among emerging adult African American females

Emerging adult African American females are at increased risk for cannabis use disorders. Ecological models suggest that African Americans' increased risk for substance use disorders and associated adverse outcomes may result from chronic exposure to contextual disadvantages, such as living in economically deprived and disorganized communities. However levels of vulnerability for developing cannabis use disorders vary, even among residents of disadvantaged neighborhoods. Therefore, studies focused on within group differences are necessary. This study examined the relationship between frequency of marijuana use and perceived neighborhood disorder. The sample included 117 African American emerging adult females (M_age = 23.6 ± 3.4). After providing informed consent, participants completed a semi-structured interview that included the Neighborhood Environment Scale and a self-report measure of marijuana use. Additionally, participants provided a urine sample that was tested for the presence of psychoactive drugs. 46% tested positive for marijuana and 45% reported using marijuana in the past 30 days. 27% reported frequent/heavy use. Results from multinomial logistic regression analysis indicated a significant relationship between perceived neighborhood disorder and heavy marijuana use (AOR = 3.3; 95% CI = 1.06 - 10.29). Findings suggest African American emerging adult female residents of economically disadvantaged neighborhoods who appraise their environments as disorganized may be at heighten risk for problematic marijuana use and should be targeted for intervention. Moreover, the findings support the need for multi-systems interventions. As policy makers consider the legalization of marijuana, it is important that differences in marijuana use behaviors and negative outcomes across groups and contexts are taken into consideration.

Cannabis use, subsequent other illicit drug use and drug use disorders: A 16-year follow-up study among Swedish adults

AIMS

To examine the association between cannabis use and subsequent other illicit drug use and drug use disorders (harmful use and dependence).

DESIGN, SETTING, PARTICIPANTS

We used survey data from a population-based cohort in Stockholm County (collected 1998-2000), with linkage to the National Patient Register. The study base comprised participants aged 20-64 years (N = 10 345), followed-up until 2014. Cox and logistic regression analyses were conducted to test associations between self-reported cannabis use and risk of subsequent other illicit drug use (three-year follow-up) and drug use disorders (16-year follow-up).

FINDINGS

The odds ratio (OR) for other illicit drug use onset at three-year follow-up for lifetime cannabis users was 7.00 (4.47-10.35, 95% CI) and for recent cannabis users 34.41 (19.14-61.88, 95% CI). Adjusting for age and AUDIT score attenuated the association, for lifetime users: OR = 5.48 (3.69-8.13, 95% CI) and OR = 5.65 (3.80-8.41, 95% CI), and for recent users: OR = 18.32 (9.88-33.99, 95% CI) and OR = 20.88 (11.19-38.95, 95% CI). For cannabis users only, the hazard ratio (HR) for drug use disorders at 16-year follow-up was 0.89 (0.31-2.61, 95%CI). For cannabis and other illicit drug users, the corresponding HR was 7.27 (3.85-13.75, 95% CI).

CONCLUSIONS

There was no independent association between cannabis use and subsequent drug use disorders. The association with subsequent drug use disorders was rather explained by other illicit drug use, which cannabis users were at higher risk of at the three-year follow-up.

Cannabis Dependence or Abuse in Kidney Transplantation: Implications for Posttransplant Outcomes

BACKGROUND

Cannabis is categorized as an illicit drug in most US states, but legalization for medical indications is increasing. Policies and guidance on cannabis use in transplant patients remain controversial.

METHODS

We examined a database linking national kidney transplant records (n = 52 689) with Medicare claims to identify diagnoses of cannabis dependence or abuse (CDOA) and associations [adjusted hazard ratio (aHR) with 95% upper and lower confidence limits (CLs)] with graft, patient, and other clinical outcomes.

RESULTS

CDOA was diagnosed in only 0.5% (n = 254) and 0.3% (n = 163) of kidney transplant recipients in the years before and after transplant, respectively. Patients with pretransplant CDOA were more likely to be 19 to 30 years of age and of black race, and less likely to be obese, college-educated, and employed. After multivariate and propensity adjustment, CDOA in the year before transplant was not associated with death or graft failure in the year after transplant, but was associated with posttransplant psychosocial problems such as alcohol abuse, other drug abuse, noncompliance, schizophrenia, and depression. Furthermore, CDOA in the first year posttransplant was associated with an approximately 2-fold increased risk of death-censored graft failure (aHR, 2.29; 95% CL, 1.59-3.32), all-cause graft loss (aHR, 2.09; 95% CL, 1.50-2.91), and death (aHR, 1.79; 95% CL, 1.06-3.04) in the subsequent 2 years. Posttransplant CDOA was also associated with cardiovascular, pulmonary, and psychosocial problems, and with events such as accidents and fractures.

CONCLUSIONS

Although associations likely, in part, reflect associated conditions or behaviors, clinical diagnosis of CDOA in the year after transplant appears to have prognostic implications for allograft and patient outcomes. Recipients with posttransplant CDOA warrant focused monitoring and support.

The association between cannabis use and psychiatric comorbidity in people with personality disorders: A population-based longitudinal study

Both personality disorders (PD) and cannabis use are highly comorbid with various psychiatric disorders. While previous research indicates specific interactions between cannabis use and schizotypal PD associated with schizophrenia, research into cannabis use among individuals with other PDs and the development of several additional psychiatric disorders is scarce. We explored the prevalence and incidence of psychiatric disorders among individuals with PDs who use cannabis, and whether individuals with PDs who use cannabis are at increased risk for developing psychiatric disorders compared to cannabis users without a PD. Finally, we examined the interaction effect between cannabis use and personality disorders on comorbid psychiatric disorders. Data from 34,653 participants in waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were analyzed. Our findings indicate that individuals with PDs who used cannabis were at increased odds for developing substance use disorders (including opioid use disorder), but not other comorbid psychiatric disorders, at 3-year follow up. No significant interaction effects were generally found between cannabis use and PD. These findings suggest that aside from specific substance use disorders, individuals with PDs are not at an increased risk for developing other psychiatric disorders following cannabis use.

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

Background: With the changing context of marijuana use, it is critical to identify effects of use. We extend previous work by examining whether marijuana use influences progression and remission through alcohol involvement stages for men and women. Methods: Data come from Waves I and II of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC, n = 34,432). We assess the potential influence of marijuana use at Wave 1 on transitions across three latent statuses of alcohol involvement between waves. We apply propensity score weighting to account for shared risk factors. Results: Marijuana use was associated cross-sectionally and longitudinally with alcohol involvement statuses for both sexes. After propensity score adjustment, men with marijuana histories were 3.50 times as likely as men without such histories to transition from no to severe problems across waves relative to staying in the same status (p < .001). Women with marijuana histories were 1.74 times as likely as women without such histories to transition from no problems at Wave 1 to moderate problems at Wave 2 (p = .030) and 0.13 times as likely as women without such histories to transition from severe problems to no problems (p = .006). Conclusions: Results suggest that marijuana use impacts progression to more serious stages of alcohol involvement for both men and women, as well as hinders remission among women. Findings point to the importance of screening those with marijuana histories for alcohol problems, as well as the need to understand the mechanism of why marijuana use may increase the risk of alcohol problems.

Puff, puff, drink: The association between blunt and alcohol use among African American adolescents and young adults

Although African Americans report lower levels of alcohol use relative to their White counterparts, they experience higher rates of alcohol-related problems (e.g., alcohol dependence). One understudied connection between alcohol use and dependence is the dual use of illicit drugs, especially marijuana use. It is speculated that blunt use in combination with alcohol will have more adverse alcohol-related consequences among African Americans than alcohol use alone or alcohol and nonblunt marijuana use. The current study uses pooled data from the 2011-2014 National Survey on Drug Use and Health to examine the odds of alcohol dependence based on alcohol and marijuana typology in comparison to alcohol only users. Among 11,124 African American adolescents (12-17) and young adults (18-25) who consumed alcohol in the past year, 57.5%, 36.8%, and 5.7% reported alcohol use alone and in combination with blunt use and nonblunt marijuana use, respectively. Relative to alcohol users only, youth who used alcohol and blunts had increased odds of having alcohol dependence. This association was not found among youth who reported alcohol and nonblunt marijuana use. The increased rates of alcohol dependence highlight the public health concern of dual alcohol and a specific type of marijuana use (i.e., blunts) among African American youth. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Mood Disorders and Severity of Addiction in Alcohol-Dependent Patients Could Be Mediated by Sex Differences

Background: Alcohol dependence is highly prevalent in the general population; some differences in alcohol use and dependence between women and men have been described, including outcomes and ranging from biological to social variables. This study aims to compare the severity of alcohol dependence with clinical and psychopathological characteristics between sexes. Methods: A cross-sectional descriptive study was conducted in alcohol-dependent outpatients; the recruitment period was 7 years. The assessment of these patients was carried out by obtaining sociodemographic characteristics and using the Semi-structured Clinical Interview for Axis I and II (SCID-I and SCID-II), European version of the Addiction Severity Index (EuropASI), Beck Depression Inventory (BDI), and State-Trait Anxiety Inventory (STAI) scales. Variables were compared and analyzed. Results: The sample was composed of 178 patients (74.2% males and 25.8% females) with a mean age of 46.52 ± 9.86. No sociodemographic differences were found between men and women. Females had a higher rate of suicide attempts and depression symptoms at the treatment onset. When results of EuropASI were compared, females had worse psychological and employment results than males. According to consumption variables, males had an earlier onset of alcohol use, had more regular alcohol use, and develop alcohol dependence earlier than females. Conclusions: According to results, there are sex-dependent differences (severity and other variables such as mood or suicide) in alcohol dependence. Thus, this may implicate the need of future specific research and treatment programs based on the specific necessities of each sex.

The influence of adolescent nicotine exposure on ethanol intake and brain gene expression

Nicotine and alcohol are often co-abused. Adolescence is a vulnerable period for the initiation of both nicotine and alcohol use, which can lead to subsequent neurodevelopmental and behavioral alterations. It is possible that during this vulnerable period, use of one drug leads to neurobiological alterations that affect subsequent consumption of the other drug. The aim of the present study was to determine the effect of nicotine exposure during adolescence on ethanol intake, and the effect of these substances on brain gene expression. Forty-three adolescent female C57BL/6J mice were assigned to four groups. In the first phase of the experiment, adolescent mice (PND 36-41 days) were exposed to three bottles filled with water or nicotine (200 μg/ml) for 22 h a day and a single bottle of water 2 h a day for six days. In the second phase (PND 42-45 days), the 4-day Drinking-in-the-Dark paradigm consisting of access to 20% v/v ethanol or water for 2h or 4h (the last day) was overlaid during the time when the mice did not have nicotine available. Ethanol consumption (g/kg) and blood ethanol concentrations (BEC, mg %) were measured on the final day and whole brains including the cerebellum, were dissected for RNA sequencing. Differentially expressed genes (DEG) were detected with CuffDiff and gene networks were built using WGCNA. Prior nicotine exposure increased ethanol consumption and resulting BEC. Significant DEG and biological pathways found in the group exposed to both nicotine and ethanol included genes important in stress-related neuropeptide signaling, hypothalamic-pituitary-adrenal (HPA) axis activity, glutamate release, GABA signaling, and dopamine release. These results replicate our earlier findings that nicotine exposure during adolescence increases ethanol consumption and extends this work by examining gene expression differences which could mediate these behavioral effects.

Age of Onset, Current Use of Alcohol, Tobacco or Marijuana and Current Polysubstance Use Among Male and Female Mexican Students

Aims

This study aimed to examine alcohol, tobacco or marijuana use onset and associations between age of onset and current use, and between age of onset and current polysubstance use among a sample of Mexican young people aged 17-20 years.

Methods

Alcohol, tobacco, marijuana and other substance use were identified in a 2012 cross-sectional survey of male and female students entering first year university in Mexico City. Chi-square tests and logistic regression models examined associations between gender, age of onset, order of onset, family substance use and current polysubstance use among 22,224 students.

Results

The largest proportions of males and females initiated alcohol at age 15, tobacco at ages 15-16 and marijuana at ages 16-17. Earlier alcohol and tobacco initiation was associated with past 30-day use of the same substance. Gender differences in alcohol and tobacco use were small but males were significantly more likely than females to use marijuana and be polysubstance users. Family substance use was associated with earlier onset. There was a significant association between the earliest age of any of the three substances and current polysubstance use.

Conclusions

A number of contextual and cultural factors in Mexico may be contributing to early onset, continued use and polysubstance use and deserve attention in research and by prevention programs.

Influence of parent-youth relationship, parental monitoring, and parent substance use on adolescent substance use onset

The quality of parent-child relationships likely influences many decisions and behaviors made by early adolescents, including their alcohol and marijuana use. We examined how parent-youth relationship quality, parental monitoring, and parent substance use were associated with initiation of alcohol use, binge drinking, and marijuana use by 400 adolescents by the spring of 8th grade (ages 13-14), and changes in initiation through 9th grade (assessed 3 times; fall, winter, and spring). We measured both parent and adolescent report of parent-youth relationship quality and parental monitoring, expecting that both perspectives would uniquely contribute. Discrete Time Survival models showed that youth report of both a poorer parent-youth relationship and lower parental monitoring were associated with alcohol use, binge drinking, and marijuana use onset. Parent binge drinking also predicted youth alcohol onset and parent report of poor quality relationship predicted marijuana onset. Youth report of a poor relationship with parents was a stronger predictor for girls than boys on their alcohol use onset, and youth report of parental monitoring was more protective for girls than boys for both alcohol and marijuana use onset. Implications for preventing use of these substances during early and mid-adolescence are discussed. (PsycINFO Database Record

Legalization of recreational marijuana and community sales policy in Oregon: Impact on adolescent willingness and intent to use, parent use, and adolescent use

Studies investigating the impact of medical marijuana legalization have found no significant changes in adolescent use. In one of the few studies focused on recreational marijuana, we investigated how recreational marijuana legalization and community sales policy influenced factors that likely impact youth use (youth willingness and intent to use, parent use) as well as youth use. Legalization of recreational marijuana in Oregon coincided with our study on adolescent substance use. Cohort 1 transitioned from 8th to 9th grade prior to legalization and Cohort 2 made this transition during legalization (N = 444; 53% female). Communities were allowed to opt out of sales. Multivariate linear regression models estimated the impact of legalization and community sales policy on changes in attitudes and parent use (2 time points 1 year apart). Zero-inflated Poisson growth curve models estimated the effects on initial levels and rate of change from 8th through 9th grade (4 time points). In communities opting out of sales, the prior-to-legalization cohort was less likely to increase their willingness and intent to use marijuana, and the legalization cohort was more likely to increase intent to use. For youth who used marijuana, legalization was associated with increased use, and those in communities opting out of sales had greater growth in marijuana use. Community policy appears to impact youth attitudes toward, and use of, marijuana. Results suggest that legalization of recreational marijuana did not increase marijuana use for youth who did not use marijuana but did increase use in youth who were already using. (PsycINFO Database Record

Predictors of Patterns of Alcohol-Related Blackouts Over Time in Youth From the Collaborative Study of the Genetics of Alcoholism: The Roles of Genetics and Cannabis

OBJECTIVE

Alcohol-related blackouts (ARBs) are anterograde amnesias related to heavy alcohol intake seen in about 50% of drinkers. Although a major determinant of ARBs relates to blood alcohol concentrations, additional contributions come from genetic vulnerabilities and possible impacts of cannabis use disorders (CUDs). We evaluated relationships of genetics and cannabis use to latent class trajectories of ARBs in 829 subjects from the Collaborative Study of the Genetics of Alcoholism (COGA).

METHOD

The number of ARBs experienced every 2 years from subjects with average ages of 18 to 25 were entered into a latent class growth analysis in Mplus, and resulting class membership was evaluated in light of baseline characteristics, including CUDs. Correlations of number of ARBs across assessments were also compared for sibling pairs versus unrelated subjects.

RESULTS

Latent class growth analysis identified ARB-based Classes 1 (consistent low = 42.5%), 2 (moderate low = 28.3%), 3 (moderate high = 22.9%), and 4 (consistent high = 6.3%). A multinomial logistic regression analysis within latent class growth analysis revealed that baseline CUDs related most closely to Classes 3 and 4. The number of ARBs across time correlated .23 for sibling pairs and -.10 for unrelated subjects.

CONCLUSIONS

Baseline CUDs related to the most severe latent ARB course over time, even when considered along with other trajectory predictors, including baseline alcohol use disorders and maximum number of drinks. Data indicated significant roles for genetic factors for alcohol use disorder patterns over time. Future research is needed to improve understanding of how cannabis adds to the ARB risk and to find genes that contribute to risks for ARBs among drinkers.

A time-varying effect model for examining group differences in trajectories of zero-inflated count outcomes with applications in substance abuse research

This study proposes a time-varying effect model for examining group differences in trajectories of zero-inflated count outcomes. The motivating example demonstrates that this zero-inflated Poisson model allows investigators to study group differences in different aspects of substance use (e.g., the probability of abstinence and the quantity of alcohol use) simultaneously. The simulation study shows that the accuracy of estimation of trajectory functions improves as the sample size increases; the accuracy under equal group sizes is only higher when the sample size is small (100). In terms of the performance of the hypothesis testing, the type I error rates are close to their corresponding significance levels under all settings. Furthermore, the power increases as the alternative hypothesis deviates more from the null hypothesis, and the rate of this increasing trend is higher when the sample size is larger. Moreover, the hypothesis test for the group difference in the zero component tends to be less powerful than the test for the group difference in the Poisson component. Copyright © 2016 John Wiley & Sons, Ltd.

Cannabis Use and Cannabis Use Disorders Among Youth in the United States, 2002-2014

OBJECTIVE

To examine trends in past-year cannabis use (CU) and cannabis use disorders (CUD) among youth in the United States, when related changes began, and factors associated with these changes.

METHODS

This study used data from 288,300 persons aged 12-17 years who participated in the 2002-2014 National Survey on Drug Use and Health. Descriptive analyses and bivariable and multivariable logistic regressions were applied (using the year 2002 as the reference group for most analyses).

RESULTS

The prevalence of past-year CU among youth decreased from 15.8% in 2002 to 13.1% in 2014 (this downward trend occurred during 2002-2007 only [β = -0.0540, P < .0001]). Among youth cannabis users, the prevalence of past-year CUD decreased from 27.0% in 2002 to 20.4% in 2014, with a downward trend starting in 2011 (β = -0.0970, P = .0001). During 2002-2014, the prevalence of past-year tobacco use and alcohol use decreased and prevalences of past-year CU increased among tobacco users and among alcohol users. Our multivariable results suggest that declines in past-year tobacco use (but not alcohol use) among youth were associated with declines in past-year CU during 2010-2014. Past-year CU and CUD were higher among racial/ethnic minorities (except for non-Hispanic Asians and Hawaiians/Pacific Islanders for CU) than non-Hispanic whites and were similar between male and female youth during 2002-2014.

CONCLUSIONS

In the United States, compared to 2002, even after adjusting for covariates, CU decreased among youth during 2005-2014, and CUD declined among youth cannabis users during 2013-2014. Associations between declines in tobacco use and decreased CU suggest the importance of tobacco use control and prevention among youth.

Marijuana use and service utilization among adolescents 7 years post substance use treatment

BACKGROUND

In an environment of increasingly liberal attitudes towards marijuana use and legalization, little is known about long-term trajectories of marijuana use among clinical samples of adolescents, and how these trajectories relate to health services utilization over time.

METHODS

Latent growth curve analysis was used to identify distinct trajectories of marijuana use in a clinical sample of adolescents (N=391) over 7 years post substance use treatment in an integrated health system. We examined psychiatric problems and polysubstance use associated with the identified trajectory groups using general linear models. Nonlinear mixed-effects logistic regressions were used to examine associations between health services use and the trajectory groups.

RESULTS

We identified three marijuana use trajectory groups: (1) Abstinent (n=117); (2) Low/Stable use (n=174); and (3) Increasing use (n=100). Average externalizing and anxiety/depression scores were significantly lower over time for the Abstinent group compared to the Increasing and Low/Stable groups. The Low Stable and the Increasing group had fewer psychiatric visits over time (p<0.05) and the Low/Stable group used more substance use treatment services over time compared with the Abstinent group (p<0.001).

CONCLUSIONS

Treated adolescents showed distinct marijuana use patterns, one of which indicated a group of adolescents at risk of increased use over time. These individuals have greater psychiatric and polysubstance use over time, but may not be accessing needed services.

Tolerance to Ethanol or Nicotine Results in Increased Ethanol Self-Administration and Long-Term Depression in the Dorsolateral Striatum

Ethanol (EtOH) and nicotine are the most widely coabused drugs. Tolerance to EtOH intoxication, including motor impairment, results in greater EtOH consumption and may result in a greater likelihood of addiction. Previous studies suggest that cross-tolerance between EtOH and nicotine may contribute to the abuse potential of these drugs. Here we demonstrate that repeated intermittent administration of either EtOH or nicotine in adult male Sprague Dawley rats results in tolerance to EtOH-induced motor impairment and increased EtOH self-administration. These findings suggest that nicotine and EtOH cross-tolerance results in decreased aversive and enhanced rewarding effects of EtOH. Endocannabinoid signaling in the dorsolateral striatum (DLS) has been implicated in both EtOH tolerance and reward, so we investigated whether nicotine or EtOH pretreatment might modulate endocannabinoid signaling in this region. Using similar EtOH and nicotine pretreatment methods resulted in increased paired-pulse ratios of evoked EPSCs in enkephalin-positive medium spiny neurons in DLS slices. Thus, EtOH and nicotine pretreatment may modulate glutamatergic synapses in the DLS presynaptically. Bath application of the CB1 receptor agonist Win 55,2-212 increased the paired-pulse ratio of evoked EPSCs in control slices, while Win 55,2-212 had no effect on paired-pulse ratio in slices from either EtOH- or nicotine-pretreated rats. Consistent with these effects, nicotine pretreatment occluded LTD induction by high-frequency stimulation of the corticostriatal inputs to the dorsolateral striatum. These results suggest that nicotine and EtOH pretreatment modulates striatal synapses to induce tolerance to the motor-impairing effects of EtOH, which may contribute to nicotine and EtOH coabuse.

Social Anxiety and Cannabis-Related Impairment: The Synergistic Influences of Peer and Parent Descriptive and Injunctive Normative Perceptions

OBJECTIVES

Cannabis users, especially socially anxious cannabis users, are influenced by perceptions of other's use. The present study tested whether social anxiety interacted with perceptions about peer and parent beliefs to predict cannabis-related problems.

METHODS

Participants were 148 (36.5% female, 60.1% non-Hispanic Caucasian) current cannabis users aged 18-36 (M = 21.01, SD = 3.09) who completed measures of perceived descriptive and injunctive norms, social anxiety, and cannabis use behaviors. Hierarchical multiple regressions were employed to investigate the predictive value of the social anxiety X parent injunctive norms X peer norms interaction terms on cannabis use behaviors.

RESULTS

Higher social anxiety was associated with more cannabis problems. A three-way interaction emerged between social anxiety, parent injunctive norms, and peer descriptive norms, with respect to cannabis problems. Social anxiety was positively related to more cannabis problems when parent injunctive norms were high (i.e., perceived approval) and peer descriptive norms were low. Results further showed that social anxiety was positively related to more cannabis problems regardless of parent injunctive norms.

CONCLUSIONS

The present work suggests that it may be important to account for parent influences when addressing normative perceptions among young adult cannabis users. Additional research is needed to determine whether interventions incorporating feedback regarding parent norms impacts cannabis use frequency and problems.

"I cannot stand the boredom." Binge drinking expectancies in adolescence

INTRODUCTION

The main aim of this study is to improve our knowledge on binge drinking behavior in adolescents. In particular, we tested a model of predictors of binge drinking focusing on boredom proneness; we also examined the predictive and mediating role of drinking expectancies on binge drinking.

METHODS

A questionnaire designed to assess current drinking behavior, such as binge drinking, drinking expectancies and boredom proneness, was administered to 721 Italian adolescents (61% females) aged between 13 and 19 years (M = 15.98, SD = 1.61).

RESULTS

Structural equation modeling confirmed the evidence on drinking expectancies as predicted by boredom proneness and as predictive of adolescents' binge drinking. Interestingly, disinhibition and relief from pain seem to play a more important mediating role between boredom and alcohol outcome. Conversely, no mediation was found for interpersonal and social confidence expectancies on binge drinking.

CONCLUSIONS

In general, the results suggest that preventative interventions on alcohol misuse should focus on personality traits and underlying drinking expectancies.

Shifting patterns of variance in adolescent alcohol use: Testing consumption as a developing trait-state

While average rates of change in adolescent alcohol consumption are frequently studied, variability arising from situational and dispositional influences on alcohol use has been comparatively neglected. We used variance decomposition to test differences in variability resulting from year-to-year fluctuations in use (i.e., state-like) and from stable individual differences (i.e., trait-like) using data from the Project on Adolescent Trajectories and Health (PATH), a cohort-sequential study spanning grades 7 to 11 using three cohorts starting in grades seven, eight, and nine, respectively. We tested variance components for alcohol volume, frequency, and quantity in the overall sample, and changes in components over time within each cohort. Sex differences were tested. Most variability in alcohol use reflected state-like variation (47-76%), with a relatively smaller proportion of trait-like variation (19-36%). These proportions shifted across cohorts as youth got older, with increases in trait-like variance from early adolescence (14-30%) to later adolescence (30-50%). Trends were similar for males and females, although females showed higher trait-like variance in alcohol frequency than males throughout development (26-43% vs. 11-25%). For alcohol volume and frequency, males showed the greatest increase in trait-like variance earlier in development (i.e., grades 8-10) compared to females (i.e., grades 9-11). The relative strength of situational and dispositional influences on adolescent alcohol use has important implications for preventative interventions. Interventions should ideally target problematic alcohol use before it becomes more ingrained and trait-like.

Changes in the strength of peer influence and cultural factors on substance use initiation between late adolescence and emerging adulthood in a Hispanic sample

We examine whether peer substance use and cultural factors differentially influence the initiation of tobacco, alcohol, and marijuana use in adolescence and emerging adulthood (EA) among a community-based sample of Hispanics. Participants provided data in 11th grade (M = 16.8 years old, SD = 0.54) and emerging adulthood (M = 20.3 years old, SD = 0.6). Peer tobacco use had a stronger association with initiation of tobacco use in emerging adulthood (OR = 1.46, 95% CI = 1.13, 1.89) than in adolescence (OR = 1.20, 95% CI = 1.03, 1.40), but this pattern was not observed with initiation of alcohol or marijuana use. Cultural orientation is associated with initiation of tobacco use during EA but not with initiation of alcohol or marijuana use.

Sex differences in cannabinoid-regulated biology: A focus on energy homeostasis

Considerable strides have been made over the past 20 years in our understanding of the ligands, receptor subtypes, signal transduction mechanisms and biological actions comprising the endocannabinoid system. From the ever-expanding number of studies that have been conducted during this time, it has become increasingly clear that sex differences are the cornerstone of cannabinoid-regulated biology. Available evidence has demonstrated that these sex differences endure in the absence of gonadal steroids, and are modulated by the acute, activational effects of these hormones. This review focuses on select aspects of sexually differentiated, cannabinoid-regulated biology, with a particular emphasis on the control of energy balance. It is anticipated that it will lend impactful insight into the pervasive and diverse disparities in how males and females respond to cannabinoids--from the organismal level down to the molecular level. Additionally, it will furnish a newfound appreciation for the need to recalibrate our thinking in terms of how cannabinoids are used as therapeutic adjuvants for a broad range of clinical disorders and associated comorbidities, including body wasting and obesity.

A time-varying effect model for studying gender differences in health behavior

This study proposes a time-varying effect model that can be used to characterize gender-specific trajectories of health behaviors and conduct hypothesis testing for gender differences. The motivating examples demonstrate that the proposed model is applicable to not only multi-wave longitudinal studies but also short-term studies that involve intensive data collection. The simulation study shows that the accuracy of estimation of trajectory functions improves as the sample size and the number of time points increase. In terms of the performance of the hypothesis testing, the type I error rates are close to their corresponding significance levels under all combinations of sample size and number of time points. Furthermore, the power increases as the alternative hypothesis deviates more from the null hypothesis, and the rate of this increasing trend is higher when the sample size and the number of time points are larger.

Investigating Progression in Substance Use Initiation Using a Discrete-Time Multiple Event Process Survival Mixture (MEPSUM) Approach

The order and timing of substance initiation has significant implications for later problematic patterns of use. Despite the need to study initiation from a multivariate framework, survival analytic methods typically cannot accommodate more than two substances in one model. The Discrete-Time Multiple Event Process Survival Mixture (MEPSUM; Dean, Bauer, & Shanahan, 2014) model represents an advance by incorporating more than two outcomes and enabling establishment of latent classes within a multivariate hazard distribution. Employing a MEPSUM approach, we evaluated patterns of tobacco, alcohol, and cannabis initiation in the National Longitudinal Study of Adolescent to Adult Health (N=18,923). We found four classes that differed in their ages and ordering of peak initiation risk. Demographics, externalizing psychopathology, and personality significantly predicted class membership. Sex differences in the association between delinquency and initiation patterns also emerged. Findings support the utility of the MEPSUM approach in elucidating developmental pathways underlying clinically relevant phenomena.