Religious affiliation protects against alcohol/substance use initiation: A prospective study among healthy adolescents.

BACKGROUND: A substantial volume of the literature suggests that religious factors buffer against alcohol/substance use among adults, but research among adolescents is sparse. Further, few studies in this area have been prospective, and therefore it is unclear how religion may impact less alcohol/substance use among adolescents. METHOD: We prospectively evaluated effects of religious affiliation on initiation of alcohol/substance use in a sample of 81 psychiatrically healthy 13-14-year-olds from New England, over a 3-year period (from November 2015 to January 2019). Known risk factors were also evaluated including anxiety, depression, and impulsivity; family history of mental illness and alcohol/substance misuse; and volume of brain regions implicated in adolescent alcohol/substance misuse (assessed by Magnetic Resonance Imaging). RESULTS: Religiously affiliated adolescents were significantly less likely to initiate use of alcohol/substances (hazard ratio [HR] = 0.38). The addition of family history of alcohol/substance misuse to the model increased the predictive value of religious affiliation (HR = 0.34). Other risk factors did not diminish nor increase observed effects. CONCLUSIONS: These findings support and extend the current research by suggesting that religious affiliation protects against initiation of alcohol/substance use during early adolescence, particularly in individuals with elevated risk.

Forgiveness Mediates the Relationship Between Middle Frontal Gyrus Volume and Clinical Symptoms in Adolescents.

Dispositional forgiveness is positively associated with many facets of wellbeing and has protective implications against depression and anxiety in adolescents. However, little work has been done to examine neurobiological aspects of forgiveness as they relate to clinical symptoms. In order to better understand the neural mechanisms supporting the protective role of forgiveness in adolescents, the current study examined the middle frontal gyrus (MFG), which comprises the majority of the dorsolateral prefrontal cortex (DLPFC) and is associated with cognitive regulation, and its relationship to forgiveness and clinical symptoms in a sample of healthy adolescents. In this cross-sectional study (n = 64), larger MFG volume was significantly associated with higher self-reported dispositional forgiveness scores and lower levels of depressive and anxiety symptoms. Forgiveness mediated the relationship between MFG volume and both depressive and anxiety symptom levels. The mediating role of forgiveness in the relationship between MFG volume and clinical symptoms suggests that one way that cognitive regulation strategies supported by this brain region may improve adolescent mental health is via increasing a capacity for forgiveness. The present study highlights the relevance of forgiveness to neurobiology and their relevance to emotional health in adolescents. Future longitudinal studies should focus on the predictive quality of the relationship between forgiveness, brain volume and clinical symptoms and the effects of forgiveness interventions on these relationships.

Perceived Risk of Harm Mediates the Effects of Primary Care Alcohol Use Screening and Brief Advice in Adolescents.

PURPOSE: A previous trial found lower alcohol use risk during follow-up among adolescent primary care patients receiving computer-facilitated Screening and provider Brief Advice (cSBA) compared to treatment-as-usual (TAU). We tested whether the effect was mediated by alcohol-related perceived risk of harm (PRoH). METHODS: We analyzed data from the cSBA trial on 12- to 18-year-old patients at 9 New England practices (n = 2,096, 58% females). The trial used a quasi-experimental pre-post design with practices being their own controls (TAU followed by cSBA). Because prior alcohol experience could modify effects, we stratified analyses by baseline past 12-month drinking. Among baseline nondrinkers, we tested baseline to 3-month trajectories in PRoH of "trying alcohol" as an effect mediator for drinking at 3- and 12-month follow-up. Similarly, among those with prior drinking, we examined baseline to 3-month trajectories in PRoH of "weekly binge drinking" as an effect mediator for drinking and binge drinking. We used the Hayes product of coefficients mediation approach. RESULTS: Among baseline nondrinkers (n = 1,449), cSBA had higher PRoH compared to TAU for "trying alcohol," and higher PRoH in turn was associated with lower follow-up drinking risk. PRoH mediated their cSBA effect at 12 months, but not 3 months. Among adolescents with prior drinking (n = 647), cSBA had higher PRoH for "weekly binge drinking," which was associated with lower drinking risk at both follow-ups, and lower binge drinking risk at 3 months. PRoH mediated their cSBA effect on drinking at both follow-ups, and binge drinking at 3 months. CONCLUSION: A computer-facilitated primary care intervention enhanced adolescents' perceived alcohol risks which in turn was associated with lower drinking risk.

Perceived stress and rejection associated with functional network strength during memory retrieval in adolescents.

The brain undergoes substantial structural and functional remodeling during adolescence, including alterations in memory-processing regions influenced by stress. This study evaluated brain activation using functional magnetic resonance imaging (fMRI) during spatial memory performance using a virtual Morris water task (MWT) and examined the associations between default mode network (DMN) activation, task performance, and perceived stress and rejection. Functional magnetic resonance imaging data were acquired at 3 Tesla from 59 (34 female) adolescents (13-14 years). The NIH Emotion Toolbox was used to measure perceived stress and rejection. During the MWT, hippocampus and prefrontal cortex showed greater activation during memory retrieval relative to motor performance. Templates of brain functional networks from the Human Connectome Project study were used to extract individual participants' brain network activation strengths for the retrieval > motor contrast for two sub-networks of the default mode network: medial temporal lobe (MTL-DMN) and dorsomedial prefrontal (dMPFC-DMN). For the MTL-DMN sub-network only, activation was significantly associated with worse MWT performance (p = .008) and greater perceived stress (p = .008) and perceived rejection (p = .002). Further, MWT performance was negatively associated with perceived rejection (p = .007). These findings suggest that perceived stress and rejection are related to engagement of MTL-DMN during spatial memory and that engagement of this network impacts performance. These findings also demonstrate the utility of examining task-related network activation strength to identify the impact of perceived stress and rejection on large-scale brain network functioning during adolescence.

Trends in cannabis-related attitudes and behaviors among cannabis-using adolescent and young adult outpatients following medical cannabis legalization in Massachusetts.

Background: Among youth already using cannabis, legalization of medical cannabis may influence cannabis-related attitudes and behaviors, including increasing access through use of someone else's medical cannabis (diversion). Objective: To examine cannabis-related attitudes and behaviors (including diverted cannabis use) in cannabis-using youth in the four years following medical cannabis legalization. Additionally, we investigated characteristics of youth who used vs. did not use diverted medical cannabis. Methods: Data were collected in Boston from 2013 (when medical cannabis legislation took effect in Massachusetts) through 2016 (when recreational cannabis use became legal in Massachusetts). Cannabis-using youth (age 13-24) presenting to an outpatient adolescent substance use treatment program (ASUTP) or recruited for an adolescent medicine clinic study (AMCS) completed a confidential survey on demographic characteristics and cannabis use behaviors and attitudes. We used multiple logistic regression to analyze changes in attitudes and behaviors over three years versus the reference year (2013), controlling for demographics. We used chi-square to compare characteristics of youth reporting use of diverted medical cannabis versus those not. Results: The sample included 273 cannabis-using youth (ASUTP n = 203, AMCS n = 70; 2013 n = 67, 2014 n = 67, 2015 n = 77, 2016 n = 62). Mean ± SD age was 18.2 ± 2.5 years, 32% were female, 58% were White non-Hispanic, and 70% had college-graduate parents. In 2013, most youth reported that cannabis was easy to obtain (97.9%), and that occasional cannabis use had "no" or "slight" risk of harm (89.4%), with little change across years. In 2016, 44% of youth reported using someone else's medical cannabis, versus 15% in 2013 (aOR 4.66, 95% CI 1.81, 11.95). Youth using diverted medical cannabis had higher likelihood of reporting riding with a driver, or driving themselves, after cannabis use (both p < .01). Conclusion: Among at-risk youth in Massachusetts, use of diverted medical cannabis increased after medical cannabis legalization, and those using diverted medical cannabis reported higher risk for cannabis-related traffic injury.

Medical marijuana laws (MMLs) and dispensary provisions not associated with higher odds of adolescent marijuana or heavy marijuana use: A 46 State Analysis, 1991-2015.

Background: States are rapidly moving to reverse marijuana prohibition, most frequently through legalization of medical marijuana laws (MMLs), and there is concern that marijuana legalization may affect adolescent marijuana use. Methods: This natural-experimental study used state Youth Risk Behavior Survey (YRBS) data collected from participants in grades 9-12 from 1991 to 2015 in 46 states (N = 1,091,723). Taking advantage of heterogeneity across states in MML status and MML dispensary design, difference-in-difference estimates compared states with enacted MMLs/dispensaries to non-MML/dispensaries states. Multivariable logistic regression modeling was used to adjust for state and year effects, and student demographics. The main outcome assessed was past 30-day adolescent marijuana use ["any" and "heavy" (≥20)]. Results: In the overall sample, the adjusted odds of adolescents reporting any past 30-day marijuana use was lower in states that enacted MMLs at any time during the study period (OR 0.94, 95% CI 0.89 to 0.99; p < .05), and in states with operational dispensaries in 2015 (OR 0.93, 95% CI 0.88 to 0.99; p < .05). Among grade cohorts, only 9th graders showed a significant effect, with lower odds of use with MML enactment. We found no effects on heavy marijuana use. Conclusions: This study found no evidence between 1991 and 2015 of increases in adolescents reporting past 30-day marijuana use or heavy marijuana use associated with state MML enactment or operational MML dispensaries. In a constantly evolving marijuana policy landscape, continued monitoring of adolescent marijuana use is important for assessing policy effects.

Adolescent Gender and Age Differences in Religiously and Spiritually Motivated Types of Forgiveness and the Relationship to Depressive Symptoms.

We examined three religiously/spiritually motivated forgiveness types, forgiveness of self, others, and divine forgiveness, and their association with depressive symptoms, across adolescent gender and age groups. Twelve- to 18-year-old patients arriving for primary care completed a 3-item Forgiveness measure and the Beck Depression Inventory-II. Girls reported a higher tendency to forgive others compared to boys, and self-forgiveness and divine forgiveness tended to decline with age in both genders. We found no significant associations between forgiveness and depression among boys. Among girls, higher self-forgiveness was associated with fewer depressive symptoms. Forgiveness of others was associated with less depression only among 17-18-year-old girls. Divine forgiveness showed no association with depression in either gender. Forgiveness of self and others appears to be protective factors for depression among adolescent girls.

Pediatric Primary Care Provider Perspectives on a Computer-Facilitated Screening and Brief Intervention System for Adolescent Substance Use.

PURPOSE: This study aimed to elicit pediatric primary care providers' (PCPs) feedback on the acceptability and feasibility of implementing a tablet computer-facilitated Screening and Brief Intervention (cSBI) system for adolescent substance use in their practices. METHODS: We trained PCPs at five Boston area practices and enrolled their 12- to 18-year-old patients in a pilot randomized trial of cSBI versus usual care. PCPs completed an 18-item poststudy questionnaire. We computed frequencies and thematically coded open-ended responses. RESULTS: The analysis sample included 49 of 54 participating PCPs (90.7%). Overall, 89.8% of participants agreed the cSBI system was useful, and 81.6% reported increased confidence in providing brief counseling. Most useful were the immediate availability of screen results, talking points on substance use risks, and counseling prompts. Challenges included time and unfamiliarity with tablet computers. Many suggested electronic health record integration of cSBI to improve efficiency. CONCLUSIONS: cSBI showed high acceptability and increased confidence among pediatric PCPs. Feasibility could be enhanced by electronic health record integration.

Digital Health Technology to Enhance Adolescent and Young Adult Clinical Preventive Services: Affordances and Challenges.

The lives of adolescents and young adults (AYAs) have become increasingly intertwined with technology. In this scoping review, studies about digital health tools are summarized in relation to five key affordances-social, cognitive, identity, emotional, and functional. Consideration of how a platform or tool exemplifies these affordances may help clinicians and researchers achieve the goal of using digital health technology to enhance clinical preventive services for AYAs. Across these five affordances, considerable research and development activity exists accompanied by signs of high promise, although the literature primarily reflects demonstration studies of acceptability or small sample experiments to discern impact. Digital health technology may afford an array of functions, yet its potential to enhance AYA clinical preventive services is met with three key challenges. The challenges discussed in this review are the disconnectedness between digital health tools and clinical care, threats to AYA privacy and security, and difficulty identifying high-value digital health products for AYA. The data presented are synthesized in calls to action for the use of digital health technology to enhance clinical preventive services and to ensure that the digital health ecosystem is relevant, effective, safe, and purposed for meeting the health needs of AYA.

Adolescent SBIRT Practices Among Pediatricians in Massachusetts.

OBJECTIVES: Adolescent Screening, Brief Intervention, and Referral to Treatment (SBIRT) in primary care is a key strategy to prevent, identify, and respond to substance use problems and disorders, including opioid and other drug addictions. Despite substantial investment in recent years to increase its implementation, few studies have reported on recent levels of SBIRT implementation among pediatricians. We aimed to assess self-reported use of the SBIRT framework with adolescent patients among Massachusetts pediatricians, and describe trends since an earlier survey. METHODS: We analyzed responses to a cross-sectional survey mailed in 2017 to a representative sample of pediatricians in Massachusetts. We computed response frequencies for all SBIRT practice questions. We used the chi-square test to compare current data to data collected in 2014, as we found no demographic differences between the 2 samples. RESULTS: Nearly all pediatricians in the 2017 sample (n = 160) reported annual screening of their adolescent patients (99%). The majority reported giving positive reinforcement (87%), brief advice (92%), counseling (90%), and referral to treatment (66%) in response to screen results. Compared with 2014, a significantly higher proportion of pediatricians in 2017 referred patients who screened positively for problematic alcohol use, but perceived barriers to screening and follow-up remain, such as insufficient time to screen and patient refusal to return. CONCLUSIONS: Among respondents to a Massachusetts pediatrician survey, we found high rates of delivering SBIRT in accordance with published guidelines, though barriers remain. Whether the content of the counseling adheres to guidelines is unknown.

Morphometric Biomarkers of Adolescents With Familial Risk for Alcohol Use Disorder.

BACKGROUND: While many adolescents exhibit risky behavior, teenagers with a family history (FH+) of an alcohol use disorder (AUD) are at a heightened risk for earlier initiation of alcohol use, a more rapid escalation in frequency and quantity of alcohol consumption and developing a subsequent AUD in comparison with youth without such family history (FH-). Neuroanatomically, developmentally normative risk-taking behavior parallels an imbalance between more protracted development of the prefrontal cortex (PFC) and earlier development of limbic regions. Magnetic resonance imaging (MRI)-derived volumetric properties were obtained for these structures in FH+ and FH- adolescents. METHODS: Forty-two substance-naïve adolescents (13- to 14-year-olds), stratified into FH+ (N = 19, 13 girls) and FH- (N = 23, 11 girls) age/handedness-matched groups, completed MRI scanning at 3.0T, as well as cognitive and clinical testing. T1 images were processed using FreeSurfer to measure PFC and hippocampi/amygdalae subfields/nuclei volumes. RESULTS: FH+ status was associated with larger hippocampal/amygdala volumes (p < 0.05), relative to FH- adolescents, with right amygdala results appearing to be driven by FH+ boys. Volumetric differences also were positively associated with family history density (p < 0.05) of having an AUD. Larger subfields/nuclei volumes were associated with higher anxiety levels and worse auditory verbal learning performance (p < 0.05). CONCLUSIONS: FH+ risk for AUD is detectable via neuromorphometric characteristics, which precede alcohol use onset and the potential onset of a later AUD, that are associated with emotional and cognitive measures. It is plausible that the development of limbic regions might be altered in FH+ youth, even prior to the onset of alcohol use, which could increase later risk. Thus, targeted preventative measures are warranted that serve to delay the onset of alcohol use in youth, particularly in those who are FH+ for an AUD.

Young people who inject drugs in India have high HIV incidence and behavioural risk: a cross-sectional study.

INTRODUCTION: There are limited data on young people who inject drugs (PWID) from low- and middle-income countries where injection drug use remains a key driver of new HIV infections. India has a diverse injection drug use epidemic and estimates suggest that at least half of PWID are ≤30 years of age. We compared injection and sexual risk behaviours and HIV incidence between younger and older PWID and characterized uptake of HIV testing and harm reduction services to inform targeted HIV prevention efforts. METHODS: We analysed cross-sectional data from 14,381 PWID recruited from cities in the Northeast and North/Central regions of India in 2013 using respondent driven sampling (RDS). We compared "emerging-adult" (18 to 24 years, 26% of sample) and "young-adult" PWID (25 to 30 years, 30% of sample) to older PWID (>30 years, 44% of sample) using logistic regression to evaluate factors associated with three recent risk behaviours: needle-sharing, multiple sexual partners and unprotected sex. We estimated age-stratified cross-sectional HIV incidence using a validated multi-assay algorithm. RESULTS: Compared to older adults, emerging-adults in the Northeastern states were significantly more likely to share needles (males adjusted odds ratio [aOR] 1.82; females aOR 2.29, p < 0.01), have multiple sexual partners (males aOR 1.56; females aOR 3.75, p < 0.01), and engage in unprotected sex (males aOR 2.29, p < 0.01). In the North/Central states, young-adult males were significantly more likely to needle-share (aOR 1.23, p < 0.05) while emerging-adult males were significantly more likely to have multiple sexual partners (aOR 1.74, p < 0.05). In both regions, emerging-adults had the lowest HIV testing. Participation in harm reduction services was low across all age groups. Annual HIV incidence was higher in emerging- and young-adult PWID in the North/Central region: emerging-adults: 4.3% (95% confidence interval [CI] 3.0, 5.6); young-adults: 4.9% (95% CI 3.7, 6.2); older adults: 2.1% (95% CI 1.4, 2.8). CONCLUSIONS: Higher HIV incidence and engagement in risky behaviours among younger PWID compared to older PWID, coupled with low utilization of harm reduction services highlight the importance of targeting this population in HIV programming. Age-specific interventions focused on addressing the needs of young PWID are urgently needed to curb the HIV epidemic in this vulnerable population.

Understanding the implications of the "vaping epidemic" among adolescents and young adults: A call for action.

In the past 5 years, the use of nicotine delivered through electronic cigarettes ("e-cigarettes") has sky-rocketed among adolescents and young adults. E-cigarettes, with their high nicotine content, appealing flavors, low costs, wide availability, and discreet designs threaten 5 decades of progress in the fight against tobacco use. Aside from the increased risk of subsequent use of traditional cigarettes, marijuana, opioids, and other illicit drugs, building evidence indicates that e-cigarette use also exposes youth to several acute and long-term health risks that greatly outweigh the as-yet unfounded potential benefits from the use of e-cigarettes as a smoking reduction or cessation tool in this age group. We discuss some of the latest research on e-cigarettes, highlighting risks and harms associated with their use in adolescents and young adults, and suggest opportunities for action, including the enforcement of age, sales and marketing limitations, and concerted research and public health efforts to help curb what has become a new nicotine epidemic among youth.

Adolescent Hippocampal and Prefrontal Brain Activation During Performance of the Virtual Morris Water Task.

The frontal cortex undergoes substantial structural and functional changes during adolescence and significant developmental changes also occur in the hippocampus. Both of these regions are notably vulnerable to alcohol and other substance use, which is typically initiated during adolescence. Identifying measures of brain function during adolescence, particularly before initiation of drug or alcohol use, is critical to understanding how such behaviors may affect brain development, especially in these vulnerable brain regions. While there is a substantial developmental literature on adolescent working memory, less is known about spatial memory. Thus, a virtual Morris water task (vMWT) was applied to probe function of the adolescent hippocampus. Multiband blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) data were acquired at 3T during task performance. Participants included 32 healthy, alcohol- and drug-naïve adolescents, 13-14 years old, examined at baseline of a 3-year longitudinal MRI study. Significantly greater BOLD activation was observed in the hippocampus and surrounding areas, and in prefrontal regions involved in executive function, during retrieval relative to motor performance. In contrast, significantly greater BOLD activation was observed in components of the default mode network, including frontal medial cortex, during the motor condition (when task demands were minimal) relative to the retrieval condition. Worse performance (longer path length) during retrieval was associated with greater activation of angular gyrus/supramarginal gyrus, whereas worse performance (longer path length/latency) during motor control was associated with less activation of frontal pole. Furthermore, while latency (time to complete task) was greater in females than in males, there were no sex differences in path length (accuracy), suggesting that females required more time to navigate the virtual environment, but did so as effectively as males. These findings demonstrate that performance of the vMWT elicits hippocampal and prefrontal activation patterns in early adolescence, similar to activation observed during spatial memory retrieval in adults. Given that this task is sensitive to hippocampal function, and that the adolescent hippocampus is notably vulnerable to the effects of alcohol and other substances, data acquired using this task during healthy adolescent development may provide a framework for understanding neurobiological impact of later initiation of use.

Heterogeneity of state medical marijuana laws and adolescent recent use of alcohol and marijuana: Analysis of 45 states, 1991-2011.

OBJECTIVE: To assess associations between enactment of state medical marijuana laws (MMLs), MML restrictiveness, and past-30-day youth alcohol use overall, and in relation to marijuana use. METHOD: This quasi-experimental difference-in-difference designed study used state-level Youth Risk Behavior Survey data of 9th-12th grade students in 45 states from 1991-2011 (N D 715,014). We conducted bivariate (unadjusted) and multivariable (adjusted for state, year, individual characteristics) logistic regression analyses to examine the effect of MML enactment (yes/no) and less restrictive vs. more restrictive MMLs on five varying measures of past 30-day alcohol use (i.e., any use or binge) and alcohol and marijuana use behaviors. RESULTS: In the final adjusted analyses, MML enactment was associated with lower odds of adolescent past 30-day (1) alcohol use (OR D 0.92, [0.87, 0.97], p < .01) and (2) use of both alcohol and marijuana (OR D 0.93, [0.87, 0.99], p < .05). States with less restrictive MMLs had lower odds of past 30-day (1) alcohol use (OR D 0.94, [0.92, 0.97], p < .001), (2) binge drinking (OR D 0.96, [0.93, 0.97], p < .05), (3) alcohol use without any marijuana use (OR D 0.96, [0.93, 0.99], p < .01), and (4) use of both alcohol and marijuana (OR D 0.96, [0.92, 0.99], p < .05). CONCLUSIONS: This study found that enactment of any MML, and of less restrictive MMLs, was associated with lower odds of past 30-day adolescent alcohol use among adolescents. With continued change in state marijuana laws, it is important to monitor the effect of their enactment and implementation, as well as their specific provisions (e.g. dispensaries, home cultivation), which may differentially affect adolescent behaviors.

Screening Adolescents for Alcohol Use: Tracking Practice Trends of Massachusetts Pediatricians.

OBJECTIVES: Substance use screening is a recommended component of routine healthcare for adolescents. A 2008 survey of Massachusetts primary care physicians found high rates of screening, but low rates of validated tool use, leading to the concern that physicians may be missing substance use-related problems and disorders. In an effort to improve practice, a cross-disciplinary group developed and distributed an adolescent screening, brief intervention, and referral to treatment toolkit in 2009. A new survey of Massachusetts primary care physicians was conducted in 2014; this report describes its findings, and compares them to those from 2008. METHODS: A survey was mailed to a randomly selected sample of Massachusetts primary care physicians listed in the state Board of Registration in Medicine database. Item response frequencies were computed. Multiple logistic regression modeling was used to compare 2008 and 2014 responses, while controlling for any demographic differences between samples. RESULTS: Pediatrician respondents in 2014 (analysis N = 130) reported a high rate of annually screening patients for alcohol use (96.2%), but only 56.2% reported using a validated screening tool. Rates of screening and validated tool use were higher in 2014 than 2008. Insufficient knowledge as a reported barrier to screening decreased from 2008 to 2014. However, lack of time or staff resources remained key perceived barriers to screening. CONCLUSIONS: Our findings suggest that adolescent alcohol use screening practices among Massachusetts pediatricians have improved in recent years, during a time of national and statewide efforts to educate physicians. However, opportunities for practice improvement remain.

Trajectories of Substance Use Frequency among Adolescents Seen in Primary Care: Implications for Screening.

OBJECTIVE: To identify trajectories of substance use in a prospective cohort of adolescent primary care patients one year after a clinic visit. STUDY DESIGN: We recruited 12- to 18-year-olds from 9 New England practices between 2005 and 2008 and identified 5 trajectories of substance use. We first distinguished adolescents with no past-year use at a baseline clinic visit and at 12-month follow-up (trajectory A). For adolescents who used substances, we assessed past 90-day use at both timepoints, and identified the remaining 4 trajectories based on frequency of use. Trajectories included less than monthly use at both timepoints (trajectory B), less than monthly use increasing to monthly or more often (trajectory C), monthly or more often use decreasing to less than monthly (trajectory D), and monthly or more often use at both timepoints (trajectory E). Using multiple logistic regression, we then examined associations with substance-involved parents, siblings, and peers. RESULTS: Among 860 adolescents (mean age 15.4 years; 60.9% female; 65.6% non-Hispanic white), more than one-half (52.7%) abstained (trajectory A). The remainder were classified into trajectories B (23.8%), C (9.5%), D (5.7%), and E (8.3%). Those who abstained were least likely to have substance-involved parents (aOR 0.58; 95% CI 0.46-0.72), siblings (aOR 0.49; 95% CI 0.40-0.60), or peers (aOR 0.44; 95% CI 0.37-0.52). Those increasing from less than monthly use to using monthly or more often were more likely to have substance-involved siblings (aOR 1.58; 95% CI 1.23-2.03) or peers (aOR 1.51; 95% CI 1.06-2.17). CONCLUSIONS: Most adolescent primary care patients remained abstinent or infrequent users over 1 year, but 1 in 5 showed frequent use, with substance-involved siblings and peers predicting escalation of use.