Risky decision-making as an antecedent or consequence of adolescent cannabis use: findings from a 2-year longitudinal study.

BACKGROUND AND AIMS: Although poor decision-making (DM) has been correlated with problematic cannabis use (CU), cross-sectional designs make it difficult to determine whether poor DM represents an antecedent and/or consequence of CU. The current study measured bidirectional associations between CU and DM among adolescents over 2 years and compared these findings to those observed with episodic memory, which is consistently reported as a consequence of CU. We also measured the role of DM as a risk factor for cannabis use disorder (CUD) onset. DESIGN: Two-year longitudinal study with five bi-annual assessments. PARTICIPANTS: Participants were 401 adolescents aged 14-17 years at baseline. SETTING: Miami, Florida, USA. MEASUREMENTS: CU frequency and CUDs were assessed at each time-point through the Drug Use History Questionnaire and Structured Clinical Interview for DSM-IV, respectively. Neurocognition was assessed at odd time-points throughout the Iowa Gambling Task, Game of Dice Task and Cups Task [decision-making (DM)] and the Wechsler Memory Scale IV and California Verbal Learning Test II (episodic memory). We used latent growth curve modeling to examine bidirectional influences between CU and neurocognition over time. We applied discrete time survival analyses to determine whether baseline DM predicted CUD onset. FINDINGS: Greater lifetime CU frequency was associated with poorer episodic memory at baseline (bs = -14.84, -16.44, Ps = 0.038, 0.021). Greater CU escalation predicted lesser gains in immediate episodic memory (b = -0.05, P = 0.020). Baseline DM did not predict CU escalation (b = 0.07, P = 0.421), nor did escalation in CU predict changes in DM (b = 0.02, P = 0.352). Baseline DM also did not predict CUD onset (adjusted OR = 1.01, 95% confidence interval = 0.98-1.06). CONCLUSIONS: This study replicates findings that poorer episodic memory in adolescents appears to be a consequence of cannabis use, even among adolescents at earlier stages of use. Poor decision-making does not appear to be either a consequence of or a risk factor for escalating cannabis use or onset of cannabis use disorder among adolescents.

Nicotine treatment buffers negative behavioral consequences induced by exposure to physical and emotional stress in adolescent male mice.

Early life stress influences adult psychopathology and is associated with an increase in the propensity for drug use/seeking throughout the lifespan. Animal models corroborate that stress exposure exacerbates maladaptive reactivity to stressful stimuli while also shifting the rewarding properties of many drugs of abuse, including nicotine (NIC), a stimulant commonly misused by adolescents. Interestingly, NIC treatment can also normalize some stress-induced behavioral deficits in adult rodents; however, little is known about NIC's therapeutic efficacy following stress experienced during adolescence. The goal of the following experiments was to elucidate NIC's ability to buffer the negative consequences of stress exposure, and to further assess behavioral responsivity while on the drug. Given that stress often occurs in both physical and non-physical forms, we employed the vicarious social defeat stress (VSDS) model which allows for investigation of both physical (PS) and emotional stress (ES) exposure. After 10 days, exposure to PS and ES decreased interaction with a social target in the social interaction test (SIT), confirming social avoidance. Groups were further divided and given NIC (0.0 or 160 mg/L) in their drinking water. After 1 month of NIC consumption, the mice were exposed to the SIT, elevated plus maze (EPM), and the forced swim test (FST), respectively. NIC-treated mice showed a reversal of stress-induced deficits in the EPM and FST. Surprisingly, the mice did not show improvement in the SIT regardless of treatment condition. Together, these data confirm NIC's ability to normalize some stress-induced behavioral deficits; however, NIC's effects on social behavior need further investigation.

Developmental pathways of adolescent cannabis use: Risk factors, outcomes and sex-specific differences.

BACKGROUND: Characterizing patterns of adolescent cannabis use (CU), as well as risk factors and outcomes uniquely associated with these pathways is essential for informing treatment and prevention efforts. Yet, few studies have examined these issues among youth at-risk of engaging in problematic cannabis use. Further, research accounting for use of other substances or sex differences in patterns of CU remains exceedingly sparse. METHODS: Trajectory-based modeling was used to identify underlying CU pathways among a predominantly Hispanic (90%) sample of at-risk youth (n = 401; 46% female) across adolescence (ages∼14-18), controlling for baseline substance use and participant demographics. Adolescent psychopathology (i.e., conduct disorder, attention deficit hyperactivity disorder, anxiety, and depression) was examined as a predictor and outcome of CU. RESULTS: Three trajectories of adolescent CU were identified, with most youth (74%) engaging in relatively "low" levels of use, followed by ∼12% exhibiting an early-initiating "chronic" course, and 14% "escalating" in use. Although boys and girls both experienced increased levels of CU across adolescence, boys were more likely to exhibit escalating and chronic patterns of use. Findings revealed unique associations between adolescent CU pathways and facets of psychopathology; most notably, the relatively robust and bidirectional association between CU trajectories and conduct problem symptoms. CONCLUSIONS: Specific facets of psychopathology may confer unique associations with CU across development, including the initiation and exacerbation of CU during adolescence.

Risky sexual behavior among adolescents: The role of decision-making, problems from cannabis use and externalizing disorder symptoms.

INTRODUCTION: Previous research has demonstrated that externalizing symptoms, cannabis use problems, and poor decision-making abilities are each independently related to risky sexual behavior (RSB). However, few studies have examined the joint effect of these factors on RSB among a sample of adolescents. METHODS: The current study addresses this gap in the literature by examining how externalizing disorder symptoms, cannabis use, and decision-making abilities interact to predict RSB among a sample of adolescents (n = 204; Mage = 15.5) at-risk for escalation in cannabis use. Poisson regression was used for all analyses, and simple slope difference tests were used for all post-hoc analyses. RESULTS: A greater number of externalizing symptoms, more problems from cannabis use, and more risk disadvantageous choices on the Cups Task (CT) total trials and more risk disadvantageous choices on the CT-gain trials predicted greater RSB endorsement. Findings also highlight significant interactions between cannabis use problems and CT-total and -gain trial performance, as well as between cannabis use problems and externalizing symptoms in predicting RSB. CONCLUSION: Current treatment and prevention approaches to reduce RSB among adolescents may benefit from incorporating techniques that improve decision-making skills.

Does Cannabis Use Cause Declines in Neuropsychological Functioning? A Review of Longitudinal Studies.

Cannabis use has been linked to impairments in neuropsychological functioning across a large and continually expanding body of research. Yet insight into underlying causal relations remains limited due to the historically cross-sectional nature of studies in this area. Recently, however, studies have begun to use more informative design strategies to delineate these associations. The aim of this article is to provide a critical evaluation and review of research that uses longitudinal designs to examine the link between cannabis use and neuropsychological functioning. In summarizing the primary findings across these studies, this review suggests that cannabis use leads to neuropsychological decline. However, across most studies, these associations were modest, were present only for the group with the heaviest cannabis use, and were often attenuated (or no longer significant) after controlling for potential confounding variables. Future studies with neuropsychological data before and after initiation of cannabis use, along with careful measurement and control of "shared risk factors" between cannabis use and poorer neuropsychological outcomes, are needed to better understand who, and under what conditions, is most vulnerable to cannabis-associated neuropsychological decline. (JINS, 2017, 23, 893-902).