Heavy Marijuana Research Articles

College attendance type and subsequent alcohol and marijuana use in the U.S

BackgroundCollege attendance is a risk factor for frequent and heavy drinking and marijuana initiation but less is known about the extent to which risk varies by type of college attendance and across age. MethodsUsing panel data of young adults who were high school seniors in 1990–1998 from the Monitoring the Future study (n = 13,123), we examined the associations between college attendance at age 19/20 (4-year college full-time, other college, and non-attendance) and subsequent alcohol and marijuana use at age 21/22, 25/26, 29/30 and 35. Inverse propensity score weighting was used to balance the three college groups on pre-existing differences when examining associations with substance use outcomes. ResultsCompared to non-attendance, attending a 4-year college full-time was associated with significantly greater odds of binge drinking at age 21/22 (aOR = 1.20) and 25/26 (aOR = 1.12) and lower odds of alcohol abstinence at age 35 (aOR = 0.51). Similarly, other college attendance was associated with greater odds of binge drinking at age 21/22 (aOR = 1.08) and 25/26 (aOR = 1.04) and lower odds of abstinence at age 35 (aOR = 0.70). Four-year college full-time attendance was associated with greater odds of marijuana use at age 21/22 (aOR = 1.07) and 25/26 (aOR = 1.02) but lower odds at age 29/30 (aOR = 0.99). Other college attendance was associated with lower odds of marijuana use at age 25/26 (aOR = 0.98) and 29/30 (aOR = 0.97). Marijuana use at age 35 did not differ by college attendance. ConclusionsCollege attendance may confer elevated risk of substance use post-college. The magnitude and duration of risk vary by type of college attendance and substance.

The effects of marijuana smoking on lung function in older people.

Previous studies have associated marijuana exposure with increased respiratory symptoms and chronic bronchitis among long-term cannabis smokers. The long-term effects of smoked marijuana on lung function remain unclear. We determined the association of marijuana smoking with the risk of spirometrically defined chronic obstructive pulmonary disease (COPD) (post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio <0.7) in 5291 population-based individuals and the rate of decline in FEV1 in a subset of 1285 males and females, aged ≥40 years, who self-reported use (or non-use) of marijuana and tobacco cigarettes and performed spirometry before and after inhaled bronchodilator on multiple occasions. Analysis for the decline in FEV1 was performed using random mixed effects regression models adjusted for age, sex and body mass index. Heavy tobacco smoking and marijunana smoking was defined as >20 pack-years and >20 joint-years, respectively. ∼20% of participants had been or were current marijuana smokers with most having smoked tobacco cigarettes in addition (83%). Among heavy marijuana users, the risk of COPD was significantly increased (adjusted OR 2.45, 95% CI 1.55-3.88). Compared to never-smokers of marijuana and tobacco, heavy marijuana smokers and heavy tobacco smokers experienced a faster decline in FEV1 by 29.5 mL·year-1 (p=0.0007) and 21.1 mL·year-1 (p<0.0001), respectively. Those who smoked both substances experienced a decline of 32.31 mL·year-1 (p<0.0001). Heavy marijuana smoking increases the risk of COPD and accelerates FEV1 decline in concomitant tobacco smokers beyond that observed with tobacco alone.

Interactive effects of PTSD and substance use on suicidal ideation and behavior in military personnel: Increased risk from marijuana use.

The current study examines the unique and interactive effects of posttraumatic stress disorder (PTSD) symptoms and days using alcohol, opioids, and marijuana on PTSD symptoms, suicidal ideation, and suicidal behavior up to 1 year, later in a high-risk sample of military personnel not active in mental health treatment. Current and former military personnel at risk for suicide (N = 545; M age = 31.91 years, standard deviation = 7.27; 88.2% male) completed self-report measures of PTSD symptoms, past 30 days heavy alcohol use, opioid use, marijuana use, and current suicidal ideation via telephone at baseline and 1, 3, 6, and 12 months later. PTSD symptoms and the substance use variables (and relevant covariates) were entered as predictors of changes in PTSD symptoms, the likelihood of suicidal ideation, suicidal ideation severity, and the likelihood of suicidal behavior during the 11-month follow-up period. PTSD symptoms predicted PTSD symptoms 1 month later. PTSD symptoms and marijuana use predicted the likelihood of suicidal ideation 1 month later and suicidal behavior during the 11-month follow-up period. The interaction between PTSD symptoms and marijuana use significantly predicted increased PTSD symptoms over time and suicidal behavior. At high, but not low levels of PTSD symptoms, more days using marijuana predicted increased PTSD symptoms over time and the likelihood of suicidal behavior. Results suggest marijuana, especially for military personnel experiencing elevated PTSD symptoms may negatively impact suicidal thoughts and behavior. These results are relevant to suggestions that medical marijuana could be used in treating or augmenting treatment for PTSD.

Blood Pressure and Marijuana Use: Results from a Decade of NHANES Data.

Objectives: After 14 years of no change, new blood pressure (BP) guidelines were released; yet, the impact of marijuana on BP remains unclear. Our objective was to examine the association between marijuana use and BP. Methods: We analyzed data for adults (N = 10,709; mean age 44.8 years; 50.3% men) who completed 2005-2014 National Health and Nutrition Examination Surveys. Marijuana use was defined as never (no lifetime use), past (lifetime, not in past 30 days), and current (≥ 1 in past 30 days). Frequency of use was categorized based past 30-day use. BP was categorized as elevated BP, Stage 1 hypertension (HTN-I), or Stage 2 hypertension (HTN-II) based on updated guidelines. Results: Current users had a higher prevalence of elevated BP (19.4%), HTN-I (22.7%), HTN-II (12.9%) than never users (16.1%, 21.4%, and 11.99%) respectively; p = .03). After covariate adjustment, heavy users had 1.80 higher odds of elevated BP than never users (95% CI: 1.13-2.88). There were no statistically significant differences in BP in any other marijuana use category. Conclusions: Driven by heavy use, current users had a higher prevalence of elevated BP than never users. Patients at risk for abnormal BP should use caution when engaging in heavy marijuana use.

Child Abuse Victimization, Depression, and Substance Use Among Homeless Women: Application of General Strain Theory.

The main purpose of this study was to investigate the association between child abuse and substance use among homeless women based on a framework of General Strain Theory, which emphasizes the strong relationship between deviant behaviors and personally experienced strain. In this study, as the strain associated with substance use, child abuse experience in the past was assessed. This research tested three hypotheses about (a) the association between physical and sexual abuse during childhood and substance use (heavy drinking, marijuana use, and crack cocaine use), (b) the mediating effect of depressive symptoms, and (c) the moderating effect of positive social supports on the relationship between abuse during childhood and substance use with a survey and interview data of a randomly selected sample of 445 homeless women in a temporary shelter setting in Los Angeles County between June 2007 and March 2008. Although the results indicated that abuse during childhood was not significantly associated with any form of substance use, the results of multivariate analyses indicated that depressive symptoms fully mediated the four relationships (p < .01; physical abuse and heavy drinking, physical abuse and crack cocaine use, sexual abuse and heavy drinking, and sexual abuse and crack cocaine use). The results of this study also indicated that positive social supports significantly moderate the effect of physical (p < .01) and sexual (p < .05) abuse experience on heavy drinking, which implies that positive social supports would be significant to reduce substance use among homeless women who had a history of physical and sexual abuse during childhood.

A quasi-experimental evaluation of marijuana policies and youth marijuana use

ABSTRACTBackground: Marijuana use carries risks for adolescents’ well-being, making it essential to evaluate effects of recent marijuana policies.Objectives: This study sought to delineate associations between state-level shifts in decriminalization and medical marijuana laws (MML) and adolescent marijuana use.Methods: Using data on 861,082 adolescents (14 to 18+ years; 51% female) drawn from 1999 to 2015 state Youth Risk Behavior Surveys (YRBS), difference-in-differences models assessed how decriminalization and MML policy enactment were associated with adolescent marijuana use, controlling for tobacco and alcohol policy shifts, adolescent characteristics, and state and year trends.Results: MML enactment was associated with small significant reductions (OR = 0.911, 95% CI [0.850, 0.975]) of 1.1 percentage points in current marijuana use, with larger significant declines for male, Black, and Hispanic (2.7–3.9 percentage points) adolescents. Effects of MML increased significantly with each year of exposure (OR = 0.980, 95% CI [0.968, 0.992]). In contrast, decriminalization was not associated with significant shifts in use for the sample as a whole, but predicted significant declines in marijuana use among 14-year olds and those of Hispanic and other ancestry (1.7–4.4 percentage points), and significant increases among white adolescents (1.6 percentage points). Neither policy was significantly associated with heavy marijuana use or the frequency of use, suggesting that heavy users may be impervious to such policy signals.Conclusion: As the first study to concurrently assess unique effects of multiple marijuana policies, results assuage concerns over potential detrimental effects of more liberal marijuana policies on youth use.

A randomized controlled trial for aggression and substance use involvement among Veterans: Impact of combining Motivational Interviewing, Cognitive Behavioral Treatment and telephone-based Continuing Care

Physical aggression (towards partners or non-partners) is common among patients in treatment for substance use disorders (SUDs), including among Veteran samples; however, few treatment programs provide adjunct intervention approaches targeting reduction or prevention of aggression. The primary objectives of this comparative efficacy study were to examine the impact of adjunct aggression interventions delivered during treatment on aggression and substance use outcomes, including: a) an acute treatment phase 6-session integrated Motivational Interviewing-Cognitive Behavioral Treatment intervention (MI-CBT) for aggression and substance use prevention, b) MI-CBT plus a 12-week telephone-based Continuing Care (MI-CBT + CC) intervention, and c) an acute phase single session control condition [including some discussion of violence prevention and local violence prevention resources (Enhanced Treatment as Usual (E-TAU))]. Participants (N = 180; 165 males and 15 females) were Veterans with SUD problems and past-year severe aggression who were randomized to one of three conditions: MI-CBT, MI-CBT + CC, or E-TAU. Primary 12-month outcomes included physical aggression and injury to partners, non-partners, and total aggression (collapsing across partner and non-partner relationships). Substance use outcomes included heavy drinking, marijuana use, cocaine use, and overall illicit substance use. Due to low representation in the sample (n = 4 women in each group at follow-up), women were excluded from primary analyses. According to unadjusted analyses of male participants, all groups showed similar significant declines in aggression over time, with the MI-CBT and MI-CBT + CC groups showing significant reductions in more substance use outcomes (heavy drinking, cocaine use, overall illicit drug use) than the E-TAU group. The only significant group x time interaction was for partner physical aggression by men (those in the MI-CBT + CC group showed a significantly greater decrease from baseline to follow-up). Also, neither the MI-CBT nor MI-CBT + CC groups reported any injuring of partners during the follow-up. For heavy drinking, cocaine, marijuana and overall illicit drug use, there were significant reductions over time, but no group by time interaction effects. The findings illustrate significant reductions in aggression and substance use over time for those involved in VA SUD treatment, and a potential modest benefit of additional integrated treatment approaches (MI-CBT, MI-CBT + CC) on reducing aggression. Future studies should examine dissemination efforts in the VA, cost-effectiveness, and moderators of outcome.

Is it Selection or Socialization? Disentangling Peer Influences on Heavy Drinking and Marijuana Use Among Adolescents Whose Parents Received Brief Interventions.

This study attempted to disentangle the effects of peer selection and socialization on heavy drinking and marijuana use among adolescents whose parents received 2 distinct brief interventions (BIs). It also examined whether the two BI models—Family Check-Up and Psychoeducation—had differential effects on peer processes. Parents were randomized to BI conditions and their adolescents (61% male, age 12-19 years) completed self-report measures of days of heavy drinking, days of marijuana use, and perceived peer substance involvement at baseline, 6 months, and 12 months. Separate cross-lagged panel models revealed evidence of selection and socialization for both heavy drinking and marijuana over the first 6 months and evidence of only selection over the subsequent 6 months. Consistent with prior studies, a less robust pattern of peer processes was found when simultaneously controlling for both heavy drinking and marijuana. Results highlight the need to examine multiple substances simultaneously and suggest that the BIs may have had protective effects on peer influences over time.

Day-Level Associations Between Substance Use and HIV Risk Behavior Among a Diverse Sample of Transgender Women.

Purpose: Transgender women in the United States face elevated rates of HIV and of substance use. Studies measuring overall or aggregate levels of substance use have linked use to increased HIV transmission risk behavior (TRB). Although intensive longitudinal studies in other populations have found day-level links between substance use and TRB, no study has yet explored such links among transgender women. This study aimed to fill this gap in the literature.Methods: Utilizing survey and 60-day timeline follow-back interview data from a sample of 214 transgender women in New York City, we tested whether day-level heavy drinking, marijuana use, and/or nonprescription stimulant use were associated with odds of engaging in any sex (vs. no sexual activity) or engaging in TRB (vs. sex without TRB), adjusting for overall levels of use.Results: Multilevel models showed that each of the three substance types was associated with greater odds of engaging in sex on a given day—and more strongly so for heavy drinking among those with higher rates of heavy drinking, and for stimulant use among those with lower rates of stimulant use. Only marijuana use was associated with greater odds of TRB on a given day, but only among those with higher rates of use.Conclusion: These findings substantiate day-level links between substance use and engaging in sexual activity among transgender women, and importantly, between marijuana use and greater likelihood of TRB on a day when sexual activity occurs. This highlights the importance of addressing substance use for sexual health among transgender women especially focusing on marijuana use.

Marijuana Use in Pregnancy and While Breastfeeding.

The prevalence and perceived safety of marijuana use in pregnancy are increasing with expanding legalization. Marijuana crosses the placenta and passes into breast milk, resulting in fetal and neonatal exposure. Many women cite medical reasons for prenatal marijuana use such as nausea and vomiting of pregnancy, anxiety, and chronic pain. The scientific literature regarding marijuana in pregnancy is mixed, resulting in confusion among practitioners as to how to counsel women about risks of use. In addition, there is a paucity of literature related to marijuana use and breastfeeding. Existing pregnancy studies are predominantly retrospective cohorts with a reliance on self-report for ascertainment of exposure, which underestimates use. Many studies fail to adjust for important confounding factors such as tobacco use and sociodemographic differences. Despite the limitations of the existing evidence, there are animal and human data suggesting potential harm of cannabis use. The harms are biologically plausible given the role of the endocannabinoid system in pregnancy implantation, placentation, and fetal neurologic development. Two recent systematic reviews and meta-analyses found an association between marijuana use and adverse perinatal outcomes, especially with heavy marijuana use. In addition, three longitudinal cohort studies demonstrate a possible effect of prenatal marijuana exposure on long-term neurobehavioral outcomes. Marijuana use may be associated with growth restriction, stillbirth, spontaneous preterm birth, and neonatal intensive care unit admission. Therefore, women should be advised to refrain from using marijuana during pregnancy and lactation.

Marijuana Use and Hypothalamic-Pituitary-Adrenal Axis Functioning in Humans.

Preclinical studies suggest cannabinoids affect functioning of the hypothalamic-pituitary-adrenal (HPA) axis, but little is known about the effects of marijuana (MJ) use on HPA axis functioning in humans. Since previous work indicates substances of abuse may dysregulate the HPA axis, it is critical to understand how MJ use affects HPA axis activity. Here, we review studies that (a) examined the effects of acute MJ administration on HPA axis functioning, (b) investigated the impact of stress on HPA axis functioning in MJ users, (c) examined the effect of chronic MJ use on basal cortisol levels, and (d) studied the relationship between MJ use and the cortisol awakening response (CAR). Findings indicate acute MJ administration typically raises cortisol levels, but this increase is blunted in MJ-dependent users relative to controls. Frequent MJ users have blunted adrenocorticotropic hormone and cortisol reactivity in response to acute stress. These findings suggest HPA axis activity may be dysregulated by heavy MJ use. Alternatively, dysregulation of the HPA axis may be a risk marker for heavy MJ use. There is mixed evidence for how MJ use affects basal cortisol levels and the CAR. Future studies should consider MJ use characteristics, method of hormone collection, time when samples are collected, and environmental factors that may influence HPA axis activity in MJ users. By examining existing studies we provide one of the first reviews aimed at synthesizing the literature on HPA axis functioning in MJ users.

Human Immunodeficiency Virus Partner Notification Services Among a Representative Sample of Young Black Men Who Have Sex With Men Demonstrates Limited Service Offering and Potential Benefits of Clinic Involvement.

Partner notification (PN) is commonly offered to persons recently diagnosed with human immunodeficiency virus (HIV) to improve linkage to care and prevent onward transmission. Yet, much remains unknown about the factors associated with successful PN participation in populations at highest risk. Data were collected during the first 2 waves (2013-2015) of "uConnect," a population-based cohort study of young black men who have sex with men in Chicago (N = 618). Participants completed a biobehavioral survey and were tested for HIV. Among HIV-infected participants (N = 187), weighted logistic regression models examined the relationship between participant characteristics and being offered PN and providing partner names. 30.3% (n = 187) of the sample was HIV-positive, of which 71.7% (n = 134) were offered PN, including: 8.2% (n = 11) by the city health department; 51.5% (n = 69) by health care providers; and 40.3% (n = 54) by both. Being offered PN was significantly associated with criminal justice involvement history (adjusted odds ratio [aOR], 2.49; 95% confidence interval [CI], 1.38-4.49), volatile nitrates usage (aOR, 2.88; 95% CI, 1.20-6.94), and recent conversations with HIV outreach workers (aOR, 2.68; 95% CI, 1.25-5.77). Providing partner names was significantly associated with intermittent (aOR, 7.26; 95% CI, 1.75-30.07) and heavy (aOR, 11.47; 95% CI, 2.57-51.22) marijuana use, and being offered PN by both the city health department and health care provider (aOR, 8.36; 95% CI, 2.73-25.62). A substantial proportion of HIV-diagnosed individuals were never offered PN. Being offered PN by multiple sources is associated with participation, and improved collaboration within health systems may improve participation rates.

Falling rates of marijuana dependence among heavy users

IntroductionMarijuana use has become increasingly popular in the United States since the turn of the century, and typical use patterns among past-month marijuana users have intensified, raising concerns for an increase in cannabis use disorders (CUDs). Yet the population prevalence of CUDs has mostly remained flat. We analyzed trends in DSM-IV marijuana dependence among Daily/Near-Daily (DND) users, both overall and by age and gender, and considered potential explanations. MethodsUsing data assembled from the National Survey on Drug Use and Health (2002–2016), rates of self-reported dependence and constituent symptoms are calculated for DND marijuana users; logistic regressions with pre- and post- periods (2002–2004, 2014–2016) and a Cochrane-Armitage trend test are applied to describe temporal changes. ResultsDependence among DND users fell by 39% (26.5%–16.1%; p < .001), with significant trend. No significant change is detected at the population level. Sub-group analysis shows a steep gradient for age but not for gender. Declines are robust to sub-group analysis, except for users over 50 years old. Among dependence symptoms, most showed significant declines: reducing important activities (p < .001); use despite emotional, mental, or physical problems (p < .001); failing attempts to cutback (p < .001); lots of time getting, using, or getting over marijuana (p < .01); and failing to keep limits set on use (p < .05). Reported tolerance showed no significant change. ConclusionsThough it is unclear why, the risk of dependence formation among heavy marijuana users appear to have declined since 2002. Further research is warranted regarding explanations related to state marijuana policies, product forms, or social context.

Marital Status as a Partial Mediator of the Associations Between Young Adult Substance Use and Subsequent Substance Use Disorder: Application of Causal Inference Methods

Young adult substance use is linked with the risk of substance use disorders (SUDs) later in adulthood. Marriage may be part of this pathway because of both selection effects (early substance use reducing marriage) and socialization effects (marriage reducing later substance use and disorder). We examine whether marital status mediates the association between young adult substance use and subsequent SUDs, using causal mediation methods to strengthen inferences. Using panel data from high school seniors in 1990-1998, we examined whether the effects of two exposures (level of alcohol/marijuana use at age 19/20) on the outcomes (alcohol use disorder [AUD]/ marijuana use disorder [MUD], nondisordered use, or abstinence at age 35) were mediated by marital status at age 29/30. Propensity score weights adjusted for potential confounding regarding both the exposures and the mediator. Moderate and heavy alcohol/marijuana use at age 19/20 were associated with higher odds of AUD/MUD and lower odds of abstinence, each relative to nondisordered use, at age 35. The association between heavy alcohol use at age 19/20 and subsequent AUD was partially mediated by being unmarried at age 29/30; the associations between moderate and heavy marijuana use at age 19/20 and subsequent marijuana abstinence were partially mediated by being unmarried at age 29/30. Both selection and socialization effects related to marriage explain the perpetuation of substance use behaviors across adulthood. Selection effects on marriage seem to occur at different thresholds for young adult alcohol and marijuana use.

When Marijuana Is Used before Cigarettes or Alcohol: Demographic Predictors and Associations with Heavy Use, Cannabis Use Disorder, and Other Drug-related Outcomes.

Recent loosening of state and federal policy restrictions on marijuana, along with changes in social norms regarding marijuana use and decreases in prevalence of other types of substance use, may lead to increases in youth initiating marijuana before other types of substances such as alcohol and tobacco. We investigated predictors and potential consequences of initiating marijuana before other drugs for youth aged 12-21-years in the USA. Nationally representative, cross-sectional survey data from the US National Survey on Drug Use and Health supplied self-reported age of first marijuana, cigarettes, alcohol, other tobacco, and other illegal drug use among 12-21-year-old samples from 2004 to 2014 (n = 275,559). We first examined the degree to which initiating marijuana use first was associated with sex, age, race/ethnicity, and survey year. Then, we examined whether using marijuana first predicted heavy marijuana use, cannabis use disorder (CUD), alcohol use disorder (AUD), nicotine dependence (ND), or lifetime use of other illegal drugs. Among all survey youth (substance users and non-users), the proportion using marijuana first increased from 4.8 to 8.8% from 2004 to 2014. Those using marijuana first (vs. alcohol or cigarettes first) were more likely to be male and older and Black, American Indian/Alaskan Native, multiracial, or Hispanic than White or Asian. Among substance users and adjusting for age of onset and the number of substances used, using marijuana first was associated higher odds of heavy current marijuana use and CUD. In recent years, youth have been increasingly likely to use marijuana as their first drug and sequence of initiation is associated with race/ethnicity, gender, and age. Using marijuana first might increase the chance of heavy use and CUD.

Heavy marijuana use but not deprivation is associated with increased stressor reactivity.

Although stressors appear to motivate marijuana use, and marijuana use, in turn, is believed to induce stress system neuroadaptations, relatively little empirical work has explicitly tested for stress neuroadaptations associated with heavy marijuana use. We examined stressor reactivity to threat of unpredictable electric shock via startle potentiation among heavy marijuana users and a control group that reported minimal history of marijuana use. Heavy marijuana users were randomly assigned to 3 days of marijuana deprivation or no deprivation. This design allowed us to test contrasts for heavy (vs. minimal) use and deprivation (vs. no deprivation) on stressor reactivity. Heavy marijuana users (both deprived and nondeprived) displayed increased startle potentiation during threat of unpredictable electric shock relative to minimal use controls. In contrast, marijuana deprivation had no effect on startle potentiation. Startle potentiation was also increased among users who reported greater stress-coping motives for their marijuana use and users with cannabis use disorder diagnoses. To our knowledge, this is the 1st study to demonstrate increased reactivity to unpredictable stressors among heavy marijuana users. However, comparable increased unpredictable stressor reactivity among patients with alcohol and other substance use disorders has been previously documented. This relationship to heavy marijuana use is consistent with predictions from rodent addiction models regarding stress neuroadaptations following heavy, chronic drug use but could also represent an etiologically relevant premorbid risk characteristic. Finally, the clinical import of unpredictable stressor reactivity is reinforced by its relationships with stress-coping motives and cannabis use disorder status. (PsycINFO Database Record

Electronic Cigarettes and Future Marijuana Use: A Longitudinal Study.

Cigarettes have been strongly associated with subsequent marijuana use among adolescents, but electronic cigarettes (e-cigarettes) are now rapidly replacing traditional cigarettes among youth. This study examines associations between youth e-cigarette use and subsequent marijuana use in a national sample. Youth (aged 12-17 years) never marijuana users at wave 1 (n = 10 364; 2013-2014) from the Population Assessment of Tobacco and Health study were followed-up in 1 year (wave 2, 2014-2015). Multivariable logistic regressions were performed to evaluate associations between e-cigarette use at wave 1 and ever/heavy marijuana use in the past 12 months (P12M) and at wave 2. Among never marijuana users, e-cigarette ever use (versus never use) at wave 1 was associated with increased likelihood of marijuana P12M use (adjusted odds ratio [aOR] = 1.9; 95% confidence interval [CI]: 1.4-2.5) at wave 2. There was a significant interaction between e-cigarette use and age (P < .05) with aOR = 2.7 (95% CI: 1.7-4.3) for adolescents aged 12 to 14 and aOR = 1.6 (95% CI: 1.2-2.3) for adolescents aged 15 to 17. The association with heavy marijuana use was significant among younger adolescents (aOR = 2.5; 95% CI: 1.2-5.3) but was not among older adolescents. Heavier e-cigarette use at wave 1 yielded higher odds of P12M and heavy marijuana use at wave 2 for younger adolescents. E-cigarette use predicts subsequent marijuana use among youth, with a stronger associations among young adolescents. Reducing youth access to e-cigarettes may decrease downstream marijuana use.

Development of Marijuana Use Among Juvenile Offenders and Its Relevance for Predicting Problematic Binge Drinking: A Dual Trajectory Analysis Approach

This study builds on past research to examine the association of engagement in consistently high binge drinking behavior in adolescence with the concurrent development of marijuana use and to better understand the development of marijuana use during adolescence among a sample of juvenile offenders. This research used group-based trajectory analysis to examine heterogeneity in the development of marijuana use and dual trajectory analysis to examine the relevance of trajectories for predicting concurrent problematic binge drinking. A seven-group model best fit the marijuana use data. Marijuana use in adolescence predicted increased odds of assignment to the heavy chronic binge drinking group. The heavy chronic marijuana use group was overwhelmingly the best predictor of assignment to this group. Juvenile offenders are at risk of engagement in marijuana use and problematic levels of marijuana use. Engagement in marijuana use predicts higher odds of problematic binge drinking behavior during adolescence.

Latent Class Analysis of Intimate Partner Violence Perpetration and Victimization among Latino Emerging Adults.

While there are known developmental consequences and correlates of intimate partner violence perpetration and victimization, research focused on bidirectional and multiple forms of partner violence among Latino emerging adults is needed. This longitudinal study identified latent classes of intimate partner violence perpetration and victimization patterns among emerging adult Latinos (N = 1060; 60.6% female). A second aim examined acculturation and cumulative substance use correlates in high school, as predictors of intimate partner violence perpetration and victimization classes in emerging adulthood. Average age of participants was 15.5 years in 10th grade and 22.7 years in emerging adulthood. We identified four distinct subgroups of intimate partner violence perpetration and victimization, with 22% of individuals identified in a violence perpetration and victimization subgroup. Cumulative heavy episodic drinking and marijuana use in high school predicted belonging to the psychological bidirectional intimate partner violence group rather than the group with no violence. Cumulative marijuana use in high school, predicted belonging to the sexual bidirectional partner violence group compared to the no violence group. Our study extends the literature across developmental periods among Latino youth. The findings have implications for early adolescent prevention strategies and promotion of healthy intimate relationships.

Marijuana Use Associations with Pulmonary Symptoms and Function in Tobacco Smokers Enrolled in the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS).

Background: Marijuana is often smoked via a filterless cigarette and contains similar chemical makeup as smoked tobacco. There are few publications describing usage patterns and respiratory risks in older adults or in those with chronic obstructive pulmonary disease (COPD). Methods: A cross-sectional analysis of current and former tobacco smokers from the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) study assessed associations between marijuana use and pulmonary outcomes. Marijuana use was defined as never, former (use over 30 days ago), or current (use within 30 days). Respiratory health was assessed using quantitative high-resolution computed tomography (HRCT) scans, pulmonary function tests and questionnaire responses about respiratory symptoms. Results: Of the total 2304 participants, 1130 (49%) never, 982 (43%) former, and 192 (8%) current marijuana users were included. Neither current nor former marijuana use was associated with increased odds of wheeze (odds ratio [OR] 0.87, OR 0.97), cough (OR 1.22; OR 0.93) or chronic bronchitis (OR 0.87; OR 1.00) when compared to never users. Current and former marijuana users had lower quantitative emphysema (P=0.004, P=0.03), higher percent predicted forced expiratory volume in 1 second (FEV1%) (P<0.001, P<0.001), and percent predicted forced vital capacity (FVC%) (p<0.001, P<0.001). Current marijuana users exhibited higher total tissue volume (P=0.003) while former users had higher air trapping (P<0.001) when compared to never marijuana users. Conclusions: Marijuana use was found to have little to no association with poor pulmonary health in older current and former tobacco smokers after adjusting for covariates. Higher forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) was observed among current marijuana users. However, higher joint years was associated with more chronic bronchitis symptoms (e.g., wheeze), and this study cannot determine if long-term heavy marijuana smoking in the absence of tobacco smoking is associated with lung symptoms, airflow obstruction, or emphysema, particularly in those who have never smoked tobacco cigarettes.