The association of cannabis use on inpatient psychiatric hospital outcomes.

BACKGROUND: The associations between cannabis use and psychosis are well documented in numerous studies. There is a need to evaluate the impact of cannabis use on inpatient psychiatric utilization and outcomes. OBJECTIVES: To evaluate the impact of cannabis use on psychiatric hospital outcomes. METHODS: This study was conducted between April 20, 2015 and October 20, 2015. All patients (n = 120) admitted to Denver Health with psychotic symptoms were administered a urine toxicology screening testing for the presence of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH, the active metabolite of cannabis). Patients with positive tests were compared to those with negative tests on several measures, including length of stay, presence or lack of 30-day readmission, Brief Psychotic Rating Scale (BPRS) score, and use of antipsychotics and/or sedatives/anxiolytics. RESULTS: There were 120 patients. Twenty nine were women and 91 were men. Patients testing positive for THC-COOH had a shorter length of stay compared to patients testing negative for THC-COOH, after adjusting for age, prior psychiatric admissions, history of a psychotic-spectrum disorder, and comorbid additional substance use (p = 0.02). There were no differences in 30-day readmissions, 30-day post-discharge presentation to the Denver Health psychiatric emergency department, BPRS scores, and medication administration. CONCLUSION: Patients presenting with psychotic symptoms and cannabis use require shorter inpatient psychiatric hospitalizations. This study is the first to quantify this observation and highlights the need for future clinical decision-making tools that would ideally correlate cannabis use with the degree of potential need for expensive and scarce mental health resources, such as psychiatric hospitalization.

Depression and Marijuana Use among a Sample of Urban Females: Is Stage of Development Important?

BACKGROUND: Increasing rates of marijuana use and high rates of depression among females are major public health concerns and ambiguous study results suggest a complex association between the two. Inconsistent findings may be due to differences in sample characteristics (e.g., females vs. males) and result from differences in the relationship over time (i.e., across developmental stages). OBJECTIVES: Presently, the extent to which the relationship between depression and marijuana use differed for females in emerging adulthood, compared to young adult females, was examined. METHODS: Two hundred forty females (mean age = 23.9 ± 3.4 years) from low-income urban neighborhoods completed a semi-structured HIV-risk interview, Beck's Depression Inventory II, and provided a urine sample that was tested for the presence of psychoactive drugs. RESULTS: Approximately 35% tested positive for marijuana and 21% were experiencing depression. Results from unadjusted logistic regression analyses indicated a relationship between depression and marijuana use (OR = 2.1; 95% CI = 1.08-3.93). African Americans had higher odds of testing positive for marijuana, compared to Whites (OR = 4.6; 95% CI = 2.52-8.68). In the full model, the relationship between depression and marijuana use did not differ by developmental stage. CONCLUSIONS: Interventions aimed at reducing depression may prove beneficial for decreasing marijuana use among females between 18 and 29 years of age residing in disadvantaged communities. However, more research is needed to identify risk factors for marijuana use and to explicate the relationship between marijuana use and depression. Special consideration should be given to African American females.

Patterns of Marijuana Use and Nicotine Exposure in Patients Seeking Elective Aesthetic Procedures.

BACKGROUND: With the increasing legalization and popularity of marijuana, it is frequently and sometimes unintentionally combined with nicotine-containing products. As a consequence, patients may fail to accurately report usage during preoperative examinations or remain unaware of the inclusion of nicotine. This poses a challenge for clinicians in identifying preoperative nicotine exposure. This study aimed to establish normative data on the use of marijuana and nicotine in plastic surgery patients and correlate it with urine nicotine and cotinine levels. METHODS: All consecutive patients presenting to the authors' clinic seeking elective procedures were identified. Patients were surveyed on marijuana and nicotine use, and provided a urine sample for analysis. The survey responses, urine results, surgical treatments, and clinical outcomes were followed up prospectively. RESULTS: A total of 135 patients completed the survey and were categorized as nonusers (50%), active nicotine users (19%), active marijuana users (7%), active users of both (13%), or past users (11%). Marijuana users who denied nicotine use showed significantly elevated nicotine and cotinine levels compared with nonusers (average nicotine level, 23.1 ± 13.5 ng/mL [P = 0.00007]; average cotinine level, 221.2 ± 141.8 ng/mL [P = 0.0002]). Fewer than a third of active marijuana or nicotine users reported active use of these products during clinical encounters. There was no difference in urine levels, reported use, or other patient characteristics in patients with and without postoperative complications. CONCLUSION: This is the first descriptive study to document elevated urine nicotine levels in self-reported marijuana users in an urban, diverse patient population seeking elective plastic surgery procedures.

Characteristics of women concordant and discordant for urine drug screens for cannabis exposure and self-reported cannabis use during pregnancy.

BACKGROUND: Increasing cannabis use among pregnant people and equivocal evidence linking prenatal cannabis exposure to adverse outcomes in offspring highlights the need to understand its potential impact on pregnancy and child outcomes. Assessing cannabis use during pregnancy remains a major challenge with potential influences of stigma on self-report as well as detection limitations of easily collected biological matrices. OBJECTIVE: This descriptive study examined the concordance between self-reported (SR) cannabis use and urine drug screen (UDS) detection of cannabis exposure during the first trimester of pregnancy and characterized concordant and discordant groups for sociodemographic factors, modes of use, secondhand exposure to cannabis and tobacco, and alcohol use and cotinine positivity. STUDY DESIGN: The Cannabis Use During Development and Early Life (CUDDEL) Study is an ongoing longitudinal study that recruits pregnant individuals presenting for obstetric care, who report lifetime cannabis use as well as using (n = 289) or not using cannabis (n = 169) during pregnancy. During the first trimester pregnancy visit, SR of cannabis use and a UDS for cannabis, other illicit drugs and nicotine are acquired from eligible participants, of whom 333 as of 05/01/2023 had both. RESULTS: Using available CUDDEL Study data on both SR and UDS (n = 333; age 26.6 ± 4.7; 88.6% Black; 45.4% below federal poverty threshold; 56.5% with paid employment; 89% with high school education; 22% first pregnancy; 12.3 ± 3.6 weeks gestation), we classified pregnant individuals with SR and UDS data into 4 groups based on concordance (k = 0.49 [95% C.I. 0.40-0.58]) between SR cannabis use and UDS cannabis detection during the first trimester: 1) SR+/UDS+ (n = 107); 2) SR-/UDS- (n = 142); 3) SR+/UDS- (n = 44); 4) SR-/UDS+ (n = 40). Those who were SR+/UDS- reported less frequent cannabis use and fewer hours under the influence of cannabis during their pregnancy. Those who were SR-/UDS+ were more likely to have joined the study at a lower gestational age with 62.5% reporting cannabis use during their pregnancy prior to being aware that they were pregnant. Of the 40 SR-/UDS+ women, 14 (i.e., 35%) reported past month secondhand exposure, or blunt usage. In the subset of individuals with SR and UDS available at trimester 2 (N = 160) and 3 (N = 140), concordant groups were mostly stable and > 50% of those in the discordant groups became concordant by the second trimester. Classifying individuals as exposed or not exposed who were SR+ and/or UDS+ resulted in minor changes in group status based on self-report at screening. CONCLUSION: Overall, there was moderate concordance between SR and UDS for cannabis use/exposure during pregnancy. Instances of SR+/UDS- discordancy may partially be attributable to lower levels of use that are not detected on UDS. SR-/UDS+ discordancy may arise from recent use prior to knowledge of pregnancy, extreme secondhand exposure, deception, and challenges with completing questionnaires. Acquiring both self-report and biological detection of cannabis use/exposure allows for the examination of convergent evidence. Classifying those who are SR+ and/or UDS+ as individuals who used cannabis during their first trimester after being aware of their pregnancy resulted in only a minor change in exposure status; thus, relying on self-report screening, at least in this population and within this sociocultural context likely provides an adequate approximation of cannabis use during pregnancy.

The impact of cannabis use proximal to sleep and cannabinoid metabolites on sleep architecture.

STUDY OBJECTIVES: Cannabis is a common sleep aid; however, the effects of its use prior to sleep are poorly understood. This study aims to determine the impact of nonmedical whole plant cannabis use 3 hours prior to sleep and measured cannabis metabolites on polysomnogram measures. METHODS: This is a cross-sectional study of 177 healthy adults who provided detailed cannabis use history, underwent a 1-night home sleep test and had measurement of 11 plasma and urinary cannabinoids, quantified using mass spectroscopy, the morning after the home sleep test. Multivariable models were used to assess the relationship between cannabis use proximal to sleep, which was defined as use 3 hours before sleep, and individual home sleep test measurements. Correlation between metabolite concentrations and polysomnogram measures were assessed. RESULTS: In adjusted models, cannabis use proximal to sleep was associated with increased wake after sleep onset (median 60.5 vs 45.8 minutes), rate ratio 1.59 (1.22, 2.05), and increased proportion of stage 1 sleep (median 15.2% vs 12.3%), effect estimate 0.16 (0.06, 0.25). Compared to nonusers, frequent cannabis users (> 20 days per month) also had increased wake after sleep onset and stage 1 sleep, in addition to increased rapid eye movement latency and decreased percent sleep efficiency. Δ9-tetrahydrocannabinol metabolites correlated with these home sleep test measures. CONCLUSIONS: Cannabis use proximal to sleep was associated with minimal changes in sleep architecture. Its use was not associated with measures of improved sleep including increased sleep time or efficiency and may be associated with poor quality sleep through increased wake onset and stage 1 sleep. CITATION: Althoff MD, Kinney GL, Aloia MS, Sempio C, Klawitter J, Bowler RP. The impact of cannabis use proximal to sleep and cannabinoid metabolites on sleep architecture. J Clin Sleep Med. 2024;20(10):1615-1625.

Using measured cannabidiol and tetrahydrocannabinol metabolites in urine to differentiate marijuana use from consumption of commercial cannabidiol products.

CONTEXT: Detecting marijuana use is a component of most urine drug screens targeting a single Δ9-tetrahydrocannabinol metabolite. Recently, the non-intoxicating cannabinoid, cannabidiol (CBD), has gained popular acceptance for a myriad of reasons. Commercially available CBD products sold without purity regulations have become ubiquitous. Many products contain trace tetrahydrocannabinol. Long-term or high dose use of CBD products can result in tetrahydrocannabinol exposures, potentially producing a positive marijuana drug test. These results are not false positives since marijuana biomarkers are present, but inaccurately identify donors as marijuana users. Addressing this conundrum, we developed an assay discriminating marijuana use from the use of CBD contaminated with tetrahydrocannabinol. METHODS: Following the synthesis of a primary CBD metabolite, a LC-MS/MS assay was developed measuring the urinary metabolites tetrahydrocannabinol, 11-nor-carboxy-Δ9-tetrahydrocannabinol, CBD, and 7-carboxy-cannabidiol. The assay was utilized on 425 patients claiming CBD use, and sixteen samples from trusted users of commercial CBD products. RESULTS AND DISCUSSION: Clear data clusters enabled metabolic cut-points assignments. Forty-three percent of samples contained CBD metabolites in ten-fold excess to tetrahydrocannabinol metabolites which was then used as a set point to classify donors as CBD users. An excess of tetrahydrocannabinol metabolites classify donors as marijuana users. Additionally, urine samples were procured from donors personally known to use commercial CBD ad libitum, yet abstain from tetrahydrocannabinol. Results from trusted users substantiated the use of the resulting metabolic ratios despite 11-carboxy-tetrahydrocannabinol measured in 75% of these samples. CONCLUSION: A method has been developed and utilized to distinguish marijuana use from tetrahydrocannabinol exposure from contaminated CBD use.

Reduced urinary opioid levels from pain management patients associated with marijuana use.

Aim: Marijuana use has been postulated to modulate opioid use, dependence and withdrawal. Broad target drug testing results provide a unique perspective to identify any potential interaction between marijuana use and opioid use. Materials & methods: Using a dataset of approximately 800,000 urine drug test results collected from pain management patients of a time from of multiple years, creatinine corrected opioid levels were evaluated to determine if the presence of the primary marijuana marker 11-nor-carboxy-tetrahydrocannabinol (THC-COOH) was associated with statistical differences in excreted opioid concentrations. Results & conclusion: For each of the opioids investigated (codeine, morphine, hydrocodone, hydromorphone, oxycodone, oxymorphone, fentanyl and buprenorphine), marijuana use was associated with statistically significant lower urinary opiate levels than in samples without indicators of marijuana use.

Self-Reported Use of Tobacco, E-cigarettes, and Marijuana Versus Urinary Biomarkers.

BACKGROUND: Surveys have been instrumental in describing adolescent use of tobacco, electronic cigarettes (e-cigarettes), and marijuana. However, objective biomarker data are lacking. We compared adolescent self-reported use to urinary biomarkers. METHODS: From April 2017 to April 2018, adolescents 12 to 21 years old completed an anonymous questionnaire regarding tobacco, e-cigarette, and marijuana use and provided a urine sample. Urine was analyzed for biomarkers cotinine, total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, and tetrahydrocannabinolic acid (THCA). RESULTS: Of 517 participants, 2.9% reported using tobacco, 14.3% e-cigarettes, and 11.4% marijuana in the past week. Only 2% reporting no smoking had total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol levels above cutoff (14.5 pg/mL); 2% of non-e-cigarette users had cotinine above cutoff (10 ng/mL); 2% of those denying marijuana use had THCA above cutoff (10 ng/mL). Daily e-cigarette users showed significantly higher median cotinine than nondaily users (315.4 [interquartile range (IQR) 1375.9] vs 1.69 ng/mL [IQR 28.2]; P < .003). Overall, 40% who reported using nicotine-free products had cotinine >10 ng/mL. Pod users' median cotinine was significantly higher than in nonpod users (259.03 [IQR 1267.69] vs 1.61 ng/mL [IQR 16.3]; P < .003). Median THCA among daily marijuana users was higher than in nondaily users (560.1 [IQR 1248.3] vs 7.2 ng/mL [IQR 254.9]; P = .04). Sixty-one percent of those with cotinine >10 ng/mL vs 39% of those with cotinine<10 ng/mL had THCA >10 ng/mL (P < .001). CONCLUSIONS: Adolescents' self-report correlated with measured urinary biomarkers, but subjects were unaware of their nicotine exposure. More frequent e-cigarette and pod use correlated with elevated biomarkers. Co-use of tobacco, e-cigarettes, and marijuana was corroborated by higher THCA in those with higher cotinine.

Predictors of correspondence between self-reported substance use and urinalysis screening among a racially diverse cohort of young men who have sex with men and transgender women.

It is unknown if estimates of illicit drug use among young men who have sex with men and transgender women (YMSM/TW) may be biased due to historical distrust of research or reliable due to more accepting norms for use. Research is needed to examine the validity of drug use self-reports among YMSM/TW. Data came from an ongoing longitudinal study of YMSM/TW aged 16-29 living in Chicago (analytic N = 1029). Baseline urinalysis screens for marijuana, ecstasy, amphetamine, methamphetamine, cocaine, benzodiazepine, and opiate metabolites were compared to self-reported use within different recall periods using measures of concordance. Generalized estimating equations logistic regressions were conducted on three waves of data to identify predictors of disclosing past-6-month use of marijuana and non-marijuana drugs. Past-6-month self-reported use of all non-marijuana substances was <15%. There was excellent agreement between self-reported and drug-tested marijuana use. For other substances, sensitivities within the urinalysis detection window were <0.5 but increased with longer recall periods. Black participants had lower odds of disclosing non-marijuana drug use. Gender minority participants had lower odds of disclosing marijuana use. Participants with a history of arrest had higher odds of disclosing both marijuana and non-marijuana drug use. Wave and year of first research participation were non-significant, suggesting no systematic bias or increasing honesty associated with longer research participation. Programs that rely on self-identification of non-marijuana illicit substance use may be missing a substantial portion of drug-using YMSM/TW. Future epidemiological studies should work to reduce social desirability biases and include biomarker-based drug screenings to increase validity.

Confirmed marijuana use and lymphocyte count in black people living with HIV.

BACKGROUND: Marijuana is a commonly used recreational substance with purported analgesic and mood enhancing properties. Many people living with HIV identify marijuana as a palliative substance. However, through its main psychoactive component, tetrahydrocannabinol (THC), is known to influence the immune system. The effects of marijuana use in people with HIV are still controversial, with very scant literature in Black adults. METHODS: The current study determined the differences in the lymphocyte count, specifically the number cluster differentiation 4 and 8 (CD4+ and CD8+), among patients who urine drug tested negative for THC (n = 70) and those who tested positive for THC (n = 25). The sample included 95 Black people living with HIV, 51% female, with a mean age of 46 ± 11 years. Participants provided a urine sample for substance use testing and a trained researcher extracted clinical data from clinical charts on the day of appointment. RESULTS: After adjusting for demographic and HIV-related covariates, THC-positive patients had significantly higher CD4+ and CD8+ counts than their THC-negative counterparts. CONCLUSION: These results extend previous HIV-related immunity findings in an underrepresented group, and suggest that THC use does not reduce immune function as measured by CD count. Further research is warranted on the overall effects of THC on immune function in HIV positive patients.

Quantitative biochemical screening for marijuana use and concordance with tobacco use in urban adolescents.

BACKGROUND: Assessing the prevalence and level of exposure (dose) of tobacco and marijuana use is important in studies of harm from use of these substances. We used biochemical analysis of urine to quantitatively assess exposure to nicotine and delta 9-tetrahydrocannabinol (THC) in adolescents receiving medical care in a public hospital METHODS: Participants were 686 adolescents between 12 and 21 years old seen at Zuckerberg San Francisco General Hospital between 2012 and 2014. Urine samples were assayed using high sensitivity liquid chromatographic assays for cotinine, a major metabolite of nicotine, and 11-nor-9-carboxy-delta 9-THC (THC-COOH), a major metabolite of THC. A commonly used immunoassay screen for THC-COOH was also performed. RESULTS: The THC-COOH immunoassay substantially underestimated THC exposure, as measured with the high sensitivity assay. THC use was detected in 25% of participants, with higher prevalence with increasing age and in non-Hispanic blacks. Active tobacco smokers had an 80% prevalence of THC use (odds ratio for cigarette smoking predicting THC use 13.2). Urine cotinine and THC-COOH were significantly correlated (r = 0.60). CONCLUSIONS: The use of a high sensitivity chromatographic urine assay provides a much more complete picture of adolescent tobacco use compared to a commonly used immunoassay. The immunoassay provides high specificity but moderate sensitivity. We confirm high concordance of tobacco and marijuana use and the high predictive value of cigarette smoking in predicting marijuana use, and provide novel data on the quantitative correlation between level of exposure to nicotine and THC. Quantitative screening of nicotine and THC exposure may enhance our understanding of addiction and harm from single and dual product use.

Trends in marijuana use among pregnant women with and without nausea and vomiting in pregnancy, 2009-2016.

BACKGROUND: Cross-sectional studies indicate an elevated prevalence of prenatal marijuana use in women with nausea and vomiting in pregnancy (NVP). However, it is unknown whether differences in marijuana use by NVP status have persisted over time as marijuana becomes more acceptable and accessible and prenatal use increases overall. We compared trends in prenatal marijuana use by NVP status in the first trimester of pregnancy using data from Kaiser Permanente Northern California's (KPNC) large healthcare system. METHODS: The sample comprised KPNC pregnant women aged ≥12 who completed a self-administered questionnaire on marijuana use and a urine toxicology test for cannabis during standard prenatal care from 2009 to 2016. The annual prevalence of marijuana use via self-report or toxicology by NVP status was estimated using Poisson regression with a log link function, adjusting for sociodemographics and parity. We tested for linear trends and differences in trends by NVP. RESULTS: Of 220,510 pregnancies, 38,831 (17.6%) had an NVP diagnosis. Prenatal marijuana use was elevated each year among women with NVP. The adjusted prevalence of use increased significantly from 2009 to 2016 at an annual rate of 1.086 (95%CI = 1.069-1.104) among women with NVP, from 6.5% (95%CI = 5.7%-7.2%) to 11.1% (95%CI = 0.2%-12.0%), and 1.069 (95%CI = 1.059-1.080) among women without NVP, from 3.4% (95%CI = 3.2%-3.7%) to 5.8% (95%CI = 5.5%-6.1%). Trends did not vary by NVP status. DISCUSSION: The prevalence of prenatal marijuana use has remained elevated over time among women with NVP. Clinicians should ask pregnant patients about their reasons for marijuana use and treat NVP with evidence-based interventions.

"Positive" urine testing for Cannabis is associated with increased risk of traffic crashes.

Although recent Cannabis use is widely reported to be associated with drug-related traffic accidents, the evidence that Cannabis users show an increased risk of being involved in road crashes is still not unequivocally proved. The purpose of the present work is to provide an objective assessment of this hypothesis, by comparing the frequency of occurrence of positive urine analyses in drivers involved in traffic accidents (n = 1406) with that observed in a control population undergoing mandatory urine drug testing (n = 1953). Urine analyses for drugs of abuse were performed by screening immunometric techniques followed by confirmation with UHPLC-QQQ MS, adopting a cut-off concentration for THC-COOH of 15 ng/mL. A case was classified as "positive" when a driver admitted to hospital for road traffic injuries showed urine concentrations of THC-COOH higher than the cut-off. All samples showing positive results for any other controlled drug in urine or blood alcohol concentrations >0.5 mg/mL were excluded from the study. Subjects positive to THC-COOH, and negative to all the other tested substances were 116 in Group 1 (8.2%) and 16 in Group 2 (0.8%). Subjects resulting negative to any tested substances were 1290 in Group 1 and 1937 in Group 2. The frequency of THC-COOH detection in the two groups was compared by using the "chi square" test, which resulted = 119.57, i.e. highly significant (P <<< 0.01). The Odds Ratio of the two groups was =10.88, showing a high degree of association between the presence of THC-COOH in urine and the occurrence of traffic accidents (P < 0.0001). The presented data, proving a high degree of association between Cannabis use and the occurrence of traffic accidents with injuries of the driver, support the use of urine testing for Cannabis in the procedures for the issuing of the driving licence, particularly in the case of subjects formerly or presently using Cannabis. This finding looks even more relevant in the present times, because of the increasing success of the policies of legalization of Cannabis for medical and non-medical purposes.

Impact of Regular Cannabis Use on Biomarkers of Lower Urinary Tract Function.

OBJECTIVE: To evaluate the differences in the composition and quantities of urine peptides in regular cannabis users and nonusers by liquid chromatography tandem mass spectrometry analysis. MATERIALS AND METHODS: Urine specimens from healthy control subjects and cannabis users were utilized to identify the differences in the number and quantity of urine proteins by liquid chromatography tandem mass spectrometry analysis. Significantly altered proteins were determined by a permutation testing statistical method. Heat map, dendrogram, pathway, and network analyses were performed to assess the degree of expression and the potential relationships between proteins in both groups. RESULTS: A total of 1337 proteins were detected in both groups with 19 proteins being significantly altered in cannabis users. Innate immunity and carbohydrate metabolic pathways were highly linked with upregulated proteins in the cannabis group. Additionally, 91 proteins were present and 46 proteins were absent only in cannabis users in comparison with the control cohort. Our results suggest that regular use of cannabis is associated with significant alterations in a number of urinary peptides, with a large number of proteins present or absent only in cannabis users. Pathway analyses demonstrated an increased immune response in cannabis users compared with controls. CONCLUSION: Our observations potentially indicate activation (or inhibition) of specific signaling pathways in the lower urinary tract during chronic exposure to exogenous cannabinoids. Our study provides initial proteomic knowledge for future investigations on the potential role of exocannabinoids in the development of intravesical therapies to treat lower urinary tract disorders.

Changes in marijuana use symptoms and emotional functioning over 28-days of monitored abstinence in adolescent marijuana users.

RATIONALE: Advancing marijuana prevention and intervention efforts are important given the decreasing perception of harm among adolescents and increasing marijuana legalization. OBJECTIVES: This study evaluates how a monitored abstinence protocol may contribute to emotional functioning and changes in marijuana problems that can enhance successful outcomes for non-treatment-seeking adolescent marijuana users. METHODS: Adolescent marijuana users (n = 26) and demographically matched controls (n = 30) completed 28 days of monitored abstinence confirmed by biweekly urine toxicology. Participants were given measures of emotional functioning, marijuana use symptoms, and reward sensitivity during monitored abstinence. RESULTS: All participants (n = 56) completed the protocol, and 69% of marijuana users (n = 18 of 26) were confirmed abstinent for 28 days, with all users showing decreasing marijuana use. Reductions in subsyndromal depression, positive marijuana use expectancies, and poor sleep quality were observed by the end of the monitored abstinence period (n = 26, p values < .05). Marijuana users also reported more attentional impulsivity and less responsiveness to reward stimuli during the second week of abstinence compared to controls. Later age of onset of regular marijuana use and more cumulative lifetime use were associated with a greater degree of emotional change and increased recognition of the negative effects of marijuana use. CONCLUSIONS: Monitored abstinence programs may be beneficial in reducing marijuana use, subsyndromal emotional distress symptoms, and changing beliefs about marijuana use. Future prevention and intervention efforts may consider targeting reward sensitivity and impulsivity, in addition to marijuana use, expectancies, and emotional functioning.