Sociodemographic and Behavioral Risk Correlates of PrEP Interest and Use Among Young Adults Experiencing Homelessness in Los Angeles.

Young adults experiencing homelessness (YAEH) are at elevated risk for HIV compared to their stably housed peers. Preexposure prophylaxis (PrEP) is highly effective at preventing HIV infection, yet YAEH have been largely overlooked in PrEP efforts to date despite YAEH reporting high overall interest in PrEP. We assessed individual, social, and structural variables associated with PrEP interest and use among a sample of 195 YAEH (ages 18-25) recruited from drop-in centers across Los Angeles County who met criteria for HIV risk. In the current sample, though most had heard of PrEP (81.0%), the majority were not interested in taking PrEP (68.2%) and only a minority had used/were using PrEP (11.8%). YAEH who identified as sexual and/or gender minority, reported knowing someone who had used PrEP, or recently accessed sexual health services were more likely to have used and/or reported interest in using PrEP. Those who reported more episodes of heavy drinking were less likely to report having used PrEP. Suggestions are provided for better integrating PrEP-related services into existing behavioral and health service programs for YAEH, as well as leveraging peers and fostering positive social norms to reduce PrEP-related stigma and increase interest and use of PrEP among YAEH.

Longitudinal associations among experiences of sexual assault, posttraumatic stress disorder symptoms, and heavy drinking in young adults.

Prior research with young adults has demonstrated clear associations between experiences of sexual assault, symptoms of posttraumatic stress disorder (PTSD), and alcohol use, but most studies have been cross-sectional or have not considered multiple theoretical pathways to understand these associations. Using six waves of data from a longitudinal cohort sample of 1,719 young adults, we examined associations among experiences of past-year sexual assault (i.e., rape, unwanted sexual touching, and physical intimidation in a sexual way), PTSD symptoms, and the frequency of binge drinking over time, allowing for the exploration of symptom-induced, interpersonal risk, and substance-induced pathways for male and female participants. For both male, ßs = 2.84 to 6.55, and female participants, ßs = 2.96 to 10.1, higher prior levels of PTSD symptoms were associated with larger increases in binge drinking over time. For female participants, higher prior levels of sexual assault were associated with larger increases in PTSD symptoms over time, ßs = 3.48 to 4.25, whereas for male participants, higher prior levels of past-year binge drinking were associated with decreases in PTSD symptoms over time, ßs = -2.75 to -0.53. Continued efforts are needed to prevent sexual assault among young adults and address PTSD symptoms among those who experience sexual assault. Interventions that target binge drinking are also needed for individuals who experience PTSD symptoms, especially young adults, to address potentially hazardous drinking before problems escalate and become chronic.

Associations between service use and behavioral health trajectories among young adults experiencing homelessness.

Purpose: To examine associations of service use (housing, mental health, substance use, education, and employment) with depression and substance use disorder (SUD) trajectories among young adults experiencing homelessness. Method: Secondary data come from 276 young adults who participated in an intervention to reduce substance use and sexual risk behaviors. Participants were recruited from three drop-in centers in Los Angeles County from 2018 to 2020, and completed surveys at baseline, 3-, 6-, 12-, and 24-months post-baseline. Latent growth curve models examined trajectories of depression and SUD; service use in the past three months was used to predict growth trajectories. Results: More frequent use of mental health services (but not other services) at baseline was associated with greater depression symptoms at baseline, linear declines in depression, and a quadratic increase in depression. Service use at baseline was not associated with likelihood of SUD at baseline or changes in SUD over time. Conclusions: Young adults in most need of behavioral services are likely to receive services for mental health, but not SUD. Use of mental health services may reduce depression symptoms over time, but continuing care may be needed to prevent symptom returns. More work is needed to connect young adults with SUD treatment and improve effectiveness of these services.

Cigarette Smoking and Depression Among U.S. Veterans: Longitudinal Associations With Posttraumatic Stress Disorder.

INTRODUCTION: Cigarette smoking and depression are associated with morbidity and mortality. Among veterans, approximately 22% are current smokers and 11%-15% have been diagnosed with depression. Although prior research suggests a strong association between smoking and depression among veterans, little research has examined trajectories of smoking and depressive symptoms and their correlates over time in this population. AIMS AND METHODS: Using parallel process growth curve modeling, we examined the longitudinal relationship between smoking and depression and tested whether posttraumatic stress disorder (PTSD) symptoms predict smoking and depression trajectories over 18 months (February 2020-August 2021). Veterans were recruited for an online, longitudinal study and responded to surveys across five-time points (baseline N = 1230; retention = 79.3%-83.3% across waves). RESULTS: Associations indicated that more frequent smoking at baseline was associated with steeper increases in depression symptom severity, and greater depression severity at baseline was associated with a less steep decrease in smoking frequency over time. PTSD was associated with less smoking at time 1 but more frequent smoking at times 3-5 as well as greater depression across all time points. CONCLUSIONS: Findings provide support that the growth trajectories of smoking and depression are linked, and PTSD symptoms are associated with these trajectories among veterans. Addressing these factors simultaneously in veteran treatment centers or through tobacco cessation efforts may be beneficial. IMPLICATIONS: This study offers strong evidence that the growth trajectories of smoking and depression are linked, and PTSD symptoms affect these trajectories among veterans, who represent a largely understudied population despite high rates of substance use and mental health problems. Results of this study strengthen the case for a more integrated treatment approach in which both smoking and mental health concerns are simultaneously addressed, which may yield more beneficial physical health and clinical outcomes for post-9/11 veterans.

Adolescent Cannabis Misuse Scale: Longitudinal Associations with Substance Use, Mental Health, and Social Determinants of Health in Early Adulthood.

BACKGROUND: Some patterns of cannabis use may presage risk for long-term negative effects. We examined associations between a novel adolescent cannabis misuse scale and early-adult life course outcomes. METHODS: We performed a secondary data analysis of a cohort of Los Angeles, CA high school students from grade 9 through age 21. Participants reported baseline individual demographic and family characteristics at grade 9, adolescent cannabis misuse (8-items) and alcohol misuse (12-items) at grade 10, and outcomes at age 21. We used multivariable regression to model the associations of cannabis misuse scale score with problem substance use (defined as any of: 30-day illegal drug use, 30-day use of another's prescription to get high, hazardous drinking) and several secondary outcomes (behavioral, mental health, academic, social determinants of health), adjusting for covariates. Parallel analyses were conducted for alcohol misuse. RESULTS: The 1,148 participants (86% retention) were 47% male, 90% Latinx, 87% US born, and 40% native English speakers. Approximately 11.4% and 15.9% of participants reported at least one item on the cannabis and alcohol misuse scales, respectively. At age 21, approximately 6.7% of participants reported problem substance use, which was associated with both Cannabis and Alcohol Misuse Scales (OR 1.31, 95%CI[1.16, 1.49] and OR 1.33, 95%CI[1.18, 1.49], respectively). Both scales were similarly associated with outcomes in all four categories. CONCLUSIONS: The Adolescent Cannabis Misuse Scale is a promising tool for identifying early patterns of substance use that predict future negative outcomes and enabling early intervention at a critical period in youth development.

Substance Use and Mental Health Outcomes from a Text Messaging-Based Intervention for Smoking Cessation Among Young People Experiencing Homelessness.

INTRODUCTION: Cigarette smoking and associated high-risk behaviors are prevalent among youth experiencing homelessness (YEH), making appropriately tailored interventions targeting smoking behavior important for this group. We pilot tested a brief text-messaging intervention (TMI) as an adjunct to standard care for YEH who smoke and found promising preliminary effects of the intervention on smoking cessation. The purpose of the present study was to test the TMI's effect on the secondary outcomes of other substance use (including use of other tobacco/nicotine devices) and mental health symptoms. METHODS: A total of 77 participants completed the pilot randomized controlled trial, with 40 receiving the TMI (174 automated text messages plus a group smoking counseling session and provision of nicotine patches). They completed an assessment at baseline and another three months later that evaluated use of other tobacco/nicotine devices, alcohol, marijuana, and anxiety and depression symptoms. RESULTS: We found that the TMI helped to reduce secondary substance use behaviors and mental health symptoms among the participants; mainly there were medium effects of the intervention on changes in other tobacco/nicotine use, drinking, and anxiety and depression symptoms. The intervention did not have an effect on number of marijuana use days in the past month; however, past 30-day marijuana users who received the intervention benefited by reducing the number of times they used marijuana per day. CONCLUSIONS: In addition to helping reduce cigarette smoking, we found that a TMI for YEH was helpful in improving secondary outcomes, suggesting the promise of the TMI on benefiting YEH even beyond targeted smoking behavior. IMPLICATIONS: This pilot study demonstrates that by targeting cigarette smoking using a text message-based intervention among youth experiencing homelessness, effects may be seen in other areas of functioning such as other substance use and mental health. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03874585. Registered March 14, 2019, https://clinicaltrials.gov/ct2/show/record/NCT03874585.

Cross-Lagged Associations of Insecure Attachment Style, Alcohol Use, and Sexual Behavior During Emerging Adulthood.

Insecure romantic attachment style has been associated with greater substance use and higher risk sexual behavior, but the temporal nature of these associations is not well-understood. This study examined whether having a more insecure attachment style was associated with greater engagement in higher-risk sexual behavior over time and, if so, whether this was mediated by more frequent alcohol use. We used three annual waves of survey data from a diverse California cohort (N = 2371) who were assessed from ages 19 to 21-22 years. Separate cross-lagged models examined temporal associations of insecure romantic attachment style (anxious and avoidant), past month alcohol use frequency, and sexual behavior (number of sex partners, condomless sex with casual and steady partners). Attachment anxiety was not directly associated with sexual behavior. Rather, a consistent pattern across waves showed that greater attachment anxiety was associated with more frequent alcohol use at the next wave, which, in turn, was associated with having more sex partners and condomless sex with casual and steady partners one year later. In contrast, greater attachment avoidance was directly associated with having fewer sex partners, and its associations with condomless sex differed across partner type and assessment waves. Attachment avoidance was unrelated to alcohol use frequency. Results indicated that both anxious and avoidant attachment styles were associated with higher-risk sexual behavior, but in different ways and through different mechanisms. Future research may want to examine whether the effectiveness of sexual risk reduction programs for young people is enhanced by discussing attachment style and tailoring the curriculum accordingly.

Loneliness and multiple health domains: associations among emerging adults.

Emerging adults (18-25 years), particularly racially/ethnically diverse and sexual and gender minority populations, may experience loneliness following major life transitions. How loneliness relates to health and health disparities during this developmental period is not well understood. We examine associations of loneliness with physical (self-rated health), behavioral (alcohol/marijuana consequences; nicotine dependence), and health behavior outcomes (weekday and weekend sleep; trouble sleeping), and investigate moderating effects by sex, race/ethnicity, and sexual/gender minority (SGM) status. Adjusted models using cross-sectional data from 2,534 emerging adults, predominantly in California, examined associations between loneliness and each outcome and tested interactions of loneliness with sex, race/ethnicity, and SGM status. Higher loneliness was significantly associated with worse self-rated health, higher marijuana consequences, less weekday sleep, and greater odds of feeling bothered by trouble sleeping. None of the interactions were significant. Findings suggest that interventions to reduce loneliness may help promote healthy development among emerging adults across subgroups.

Young Adults' Perceived Impact of COVID-19 Pandemic on Sleep and Other Functioning: Does It Differ for Sexual/Gender and Racial/Ethnic Minorities?

OBJECTIVES: Since the beginning of the COVID-19 pandemic, there has been concern that the pandemic and associated mitigation efforts would have a particularly adverse effect on communities that are marginalized. This study examined disparities in the perceived impacts of the pandemic on sleep, mental and physical health, social functioning, and substance use among young adults based on sexual/gender minority (SGM) status and race/ethnicity. METHOD: Participants were 2,411 young adults (mean age = 23.6) surveyed between July 2020-July 2021. A linear regression analysis tested SGM and racial/ethnic group differences on 17 outcomes. RESULTS: Most young adults reported little-to-no effect of the pandemic on sleep or other indicators of health and functioning. However, SGM young adults reported more adverse effects than non-SGM young adults on their sleep and most other outcomes. Hispanic young adults reported shorter sleep duration - but less pandemic-related depression, loneliness, and relationship problems - compared to non-Hispanic white young adults. We found no evidence that young adults with multiple minority statuses had especially poor pandemic-related outcomes. CONCLUSIONS: While most young adults did not perceive much impact of the pandemic, results highlight disparities across certain demographic subgroups that may need to be addressed through targeted interventions and close monitoring for long-term effects.

Pilot Randomized Clinical Trial of a Text Messaging-Based Intervention for Smoking Cessation Among Young People Experiencing Homelessness.

INTRODUCTION: Smoking rates are alarmingly high among young people experiencing homelessness (YEH), yet there are no evidence-based cessation programs for this population. This paper presents results from a pilot evaluation of a text messaging-based smoking cessation treatment, as an adjunct to brief group cessation counseling, to improve abstinence rates among 18-25-year-old smokers experiencing homelessness. The goal of this study was to estimate effect sizes for a larger trial and it was not powered to detect group differences. AIMS AND METHODS: YEH smokers who had a working cell phone with them at recruitment were randomized to receive a group counseling session, nicotine patches, and written material on quitting (n = 37) or a similar program that also included a 6-week automated text messaging intervention (TMI) to provide ongoing support for quitting (n = 40). Smoking outcomes were evaluated through a 90-day follow-up. RESULTS: Seven-day point prevalence abstinence at 90-day follow-up was higher in the TMI condition than standard condition (17.50% vs. 8.11%, respectively; Cohen's h = .37); however, the 90-day continuous abstinence rate was not statistically different from zero in either condition. Reductions in the number of days smoked in the past 30 days from baseline to follow-up were greater in the TMI condition than the standard condition (-14.24 vs. -8.62, respectively; Cohen's d = .49). CONCLUSIONS: Adding a 6-week TMI support to a brief group counseling and pharmacotherapy protocol holds promise for smoking reduction and abstinence among YEH smokers. Results indicate that further development and evaluation of the TMI in this population is warranted. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03874585. Registered March 14, 2019, https://clinicaltrials.gov/ct2/show/record/NCT03874585. IMPLICATIONS: This is the first study to evaluate the feasibility of using a text messaging-based intervention (TMI) for behavior change with 18-25 year olds experiencing homelessness, and more specifically, the first to test a TMI to provide ongoing support for smoking cessation. Small to medium effect sizes for the TMI are promising in terms of implementing a TMI using participants' own cell phones, as well as the efficacy of this approach as an adjunct to standard care (brief group counseling and pharmacotherapy) for smoking cessation among YEH.

Examining Associations Between Licensed and Unlicensed Outlet Density and Cannabis Outcomes From Preopening to Postopening of Recreational Cannabis Outlets.

BACKGROUND AND OBJECTIVES: To expand on epidemiologic studies examining associations between the legalization of recreational cannabis and use among young adults, we examined the associations between licensed and unlicensed cannabis outlet density and cannabis outcomes. METHODS: A total of 1097 young adults aged 21 and older living in Los Angeles County were surveyed before licensed recreational cannabis outlets opened (Time 1: July to December 2017) and after (Time 2: July 2018 to June 2019). Using a database of open licensed and unlicensed cannabis retailers to calculate individual-level cannabis outlet density measures, we examined associations between outlet density within a 4-mile radius of participants' residences with Time 2 outcomes of any past-month use, daily use, intentions to use, quantity used, consequences, and cannabis use disorder (CUD) symptoms. RESULTS: After controlling for demographic factors and cannabis outcomes at a time point prior to their opening (Time 1), licensed cannabis outlets were associated with young adults' cannabis use, heavy use, and intentions, and unlicensed outlets were associated with young adults' heavy cannabis use and CUD symptoms. CONCLUSION AND SCIENTIFIC SIGNIFICANCE: This study expands beyond studies of outlet prevalence to find that, after controlling for outcomes 1 year prior, licensed and unlicensed outlets were associated with young adults' cannabis outcomes. The current study is among the first to find associations between cannabis use outcomes and density of cannabis outlets among young adults using data from two time points: preopening and postopening of recreational cannabis retailers. Findings can inform policies around the density and placement of cannabis outlets. (Am J Addict 2020;00:00-00).

Effects of homophobic name-calling and verbal sexual harassment on substance use among young adults.

Verbal aggression victimization, such as homophobic name-calling, has been linked to heavier substance use among young people, but little longitudinal research has examined how different types of victimization may affect substance use or whether certain psychosocial factors moderate these risks. In a diverse cohort (N = 2,663), latent transition analysis was used to model heterogeneity in victimization (age 19) and substance use (age 20). Four victimization (high victimization, homophobic name-calling only, verbal sexual harassment only, and low victimization) and three substance use (poly-substance use, alcohol, and cannabis only, low all) classes were identified. The high victimization and homophobic name-calling only classes had the highest probabilities of transitioning into the poly-substance use class, and the high victimization class had the highest probability of transitioning into the alcohol and cannabis only class. The probability of transitioning into the low all substance use class was highest in the low victimization class and lowest in the high victimization class. For the high victimization class, greater depressive symptoms increased the odds, and better peer relationship quality decreased the odds, of transitioning into the poly-substance use and alcohol and cannabis only classes. For the homophobic name-calling only class, greater depressive symptoms increased the odds of transitioning into the poly-substance use class. Homophobic name-calling, alone or in combination with verbal sexual harassment, is a risk factor for escalating substance use in young adulthood, especially among victims with depressive symptoms.

Patterns of Substance Use and Associations with Mental, Physical, and Social Functioning: A Latent Class Analysis of a National Sample of U.S. Adults Ages 30-80.

OBJECTIVE: Trends show increased substance use among adults, yet little research on general population samples has examined differential patterns of licit and illicit substance use that can inform prevention and treatment efforts. This study identifies distinct patterns (classes) of substance use among 30- to 80-year olds, identifies demographic subgroups with the highest probability of class memberships, and compares classes on key indicators of functioning. Method: Participants (n = 1,877) were from the RAND American Life Panel. Online survey measures included current alcohol, tobacco, cannabis, and nonmedical prescription drug use, as well as mental, physical, and social functioning. Results: Latent class analysis identified four classes: "Lighter Drinking" (46.6%), "Abstaining" (33.7%), "Heavy Drinking with Cigarette/Cannabis Use" (17.1%), and "Cigarette Smoking with Prescription Drug/Cannabis Use" (2.6%). Of these classes, "Cigarette Smoking with Prescription Drug/Cannabis Use" reported the worst mental and physical functioning, and greater loneliness than the "Lighter Drinking" class. "Heavy Drinking with Cigarette/Cannabis Use" reported worse mental and physical functioning than the "Lighter Drinking" class and less social support than the "Lighter Drinking" and "Abstaining" classes. The "Abstaining" class reported consistently worse functioning than the "Lighter Drinking" class. Both polysubstance use classes were associated with younger age, less education, and lower income, and heavy drinking polysubstance use was associated with being male and unmarried. Conclusions: Although lighter drinking was the most common pattern, 20% of adults were classified into two polysubstance use classes associated with poorer functioning. Targeted efforts may be needed to reach certain subgroups of adults who are particularly susceptible to polysubstance use.

Correlates of Awareness and Use of Heated Tobacco Products in a Sample of US Young Adults in 2018-2019.

INTRODUCTION: Tobacco companies have devoted increased resources in recent years to developing and marketing heated tobacco products (HTPs) as alternatives to combustible products like cigarettes. However, little is known about correlates of awareness and use of these products in American young adults. METHODS: Two thousand four hundred ninety-seven young adults (mean age = 21.6) completed survey items on HTP awareness and lifetime use in 2018-2019. Logistic regression models compared young adults who were (1) unaware of HTPs (reference group) with those who were, (2) aware of HTPs, and (3) had ever used HTPs on demographic, tobacco, and other substance use characteristics. Among current smokers, these groups were compared on cigarette use, dependence, and readiness to quit. RESULTS: Approximately 12% of respondents (n = 293) were aware of HTPs, and 5% (n = 134) reported lifetime HTP use. Controlling for demographics, HTP awareness and use were both associated with greater use of all types of tobacco products, number of different tobacco products, and use of marijuana and other drugs. Among current smokers, HTP awareness and use correlated with heavier cigarette consumption, greater dependence, and past-month marijuana use, but not with recent quit attempts or thinking about quitting cigarettes. CONCLUSIONS: Awareness and use of HTPs among young adults were associated with greater use of tobacco products and other substances and, among current smokers, with greater cigarette dependence (but not cessation-related factors). As these products become increasingly available in the United States, additional surveillance and monitoring activities are needed to better understand use patterns, consequences, and reasons for using HTPs. IMPLICATIONS: Few studies have examined factors associated with awareness and use of heated tobacco products (HTPs) among US young adults. HTP awareness and lifetime use correlated with a range of factors, including male gender, white race/ethnicity, and tobacco and other substance use. Lifetime use of HTPs was low (5%); most lifetime HTP users reported history of other tobacco use, but a sizeable minority (14%) reported no other tobacco product use history. Among current cigarette smokers, cigarette dependence, poly-tobacco use, and marijuana use-but not cigarette cessation attempts or contemplation-were associated with greater likelihood of awareness and use of HTPs.

Motivation to quit cigarettes and alternative tobacco products: prevalence and correlates among youth experiencing homelessness.

Use of alternative tobacco products, as well as regular cigarettes, is widespread among unaccompanied youth experiencing homelessness. However, little is known about their level of motivation for quitting use of these products, factors associated with motivation to quit, or how these might vary by type of tobacco product. Unaccompanied homeless youth were sampled from 25 street and service sites in Los Angeles County (N = 469). All participants were past month tobacco users who completed a survey on their tobacco-related behaviors and cognitions, including motivation to quit, as well as background characteristics. Among self-reported users of each product, motivation to quit in the next 30 days was highest for regular cigarettes (33%), followed by e-cigarettes/vaporizers (30%), little cigars/cigarillos (25%), cigars (20%), and natural cigarettes (20%). Between 33 and 49% of youth, depending on product, were not thinking about quitting at all. Correlates of lower motivation to quit differed somewhat by product type, with the most consistent being race, more frequent use, lower perceived riskiness of the product, and using the product because of its good taste or smell. Results from this study identify a set of psychosocial and behavioral factors, some that are common across tobacco products and others that are product-specific, that may be particularly important to address in efforts to reduce tobacco use among youth experiencing homelessness. Future regulations on the sale of flavored tobacco products may also serve to increase motivation to quit in this population.

Locating Medical and Recreational Cannabis Outlets for Research Purposes: Online Methods and Observational Study.

BACKGROUND: An increasing number of states have laws for the legal sale of recreational and medical cannabis out of brick-and-mortar storefront locations. Given the proliferation of cannabis outlets and their potential for impact on local economies, neighborhood structures, and individual patterns of cannabis use, it is essential to create practical and thorough methods to capture the location of such outlets for research purposes. However, methods used by researchers vary greatly between studies and often do not include important information about the retailer's license status and storefront signage. OBJECTIVE: The aim of this study was to find methods for locating and observing cannabis outlets in Los Angeles County after the period when recreational cannabis retailers were granted licenses and allowed to be open for business. METHODS: The procedures included searches of online cannabis outlet databases, followed by methods to verify each outlet's name, address, license information, and open status. These procedures, conducted solely online, resulted in a database of 531 outlets. To further verify each outlet's information and collect signage data, we conducted direct observations of the 531 identified outlets. RESULTS: We found that 80.9% (430/531) of these outlets were open for business, of which 37.6% (162/430) were licensed to sell cannabis. Unlicensed outlets were less likely to have signage indicating the store sold cannabis, such as a green cross, which was the most prevalent form of observed signage. Co-use of cannabis and tobacco/nicotine has been found to be a substantial health concern, and we observed that 40.6% (175/430) of cannabis outlets had a tobacco/nicotine outlet within sight of the cannabis outlet. Most (350/430, 81.4%) cannabis outlets were located within the City of Los Angeles, and these outlets were more likely to be licensed than outlets outside the city. CONCLUSIONS: The findings of this study suggest that online searches and observational methods are both necessary to best capture accurate and detailed information about cannabis outlets. The methods described here can be applied to other metropolitan areas to more accurately capture the availability of cannabis in an area.

Early and Late Adolescent Factors that Predict Co-use of Cannabis with Alcohol and Tobacco in Young Adulthood.

The changing legal landscape of cannabis in the USA has coincided with changes in how cannabis is used, including its co-use with other substances. This study analyzed 10 years of data from a diverse cohort of youth (N = 2429; 54% Hispanic, 16% Asian, 16% white, 3% black, 10% multiracial) to examine predictors in early and late adolescence of co-use of alcohol with cannabis (AC) and tobacco with cannabis (TC) at age 21. Two forms of co-use were examined: concurrent (use of both substances in past month) and sequential (use of one substance right after the other). Analyses focused on four predictor domains: individual (e.g., resistance self-efficacy), peer (e.g., time spent around peers who use), family (e.g., sibling use), and neighborhood (i.e., perceived alcohol and drug problems in neighborhood). For each co-use combination (AC or TC), we estimated parallel process piecewise latent growth models in a structural equation modeling framework using Mplus v8. The final AC and TC co-use models included all predictor variables from the four domains. Increases in positive expectancies and time spent around peers who use AC, as well as steeper decreases in resistance self-efficacy, were all related to a greater likelihood of AC co-use in young adulthood. Increases in sibling TC use and time spent around peers who use TC, as well as steeper decreases in resistance self-efficacy, were all related to a greater likelihood of TC co-use in young adulthood. Overall, findings highlight the importance of addressing peer influence in prevention programming during both early and late adolescence.

Disentangling Within- and Between-Person Effects of Shared Risk Factors on E-cigarette and Cigarette Use Trajectories From Late Adolescence to Young Adulthood.

BACKGROUND: Longitudinal studies report associations between use of electronic cigarettes (ECs) and cigarettes over time among young people, but do not distinguish within- from between-person effects, which complicates interpretation of findings. Further, the role of shared risk factors, such as substance use and mental health, in explaining longitudinal associations between EC and cigarette use remains unclear. This study used within- and between-person analyses to assess longitudinal associations between youths' EC and cigarette use and shared risk factors. METHODS: Between 2015 and 2017, 2039 youths completed three Web-based surveys, allowing us to model EC and cigarette use from ages 16 to 20. Auto-regressive latent growth models with structured residuals (ALT-SR) examined both between-person and within-person associations between past-month frequency of EC use, cigarette use, and third variables (alcohol and marijuana use, mental health symptoms) over time. RESULTS: Models revealed robust reciprocal associations between EC and cigarette use, such that more frequent EC use at one time predicted more frequent cigarette use at the subsequent time, and vice versa. Between-person analyses showed associations between shared risk factors and both EC and cigarette use. However, shared risk factors did not predict frequency of subsequent EC and cigarette use in within-person analyses. CONCLUSIONS: Findings add to a growing body of research suggesting that EC use among youth is prospectively associated with progression toward greater cigarette use. Shared risk factors may help explain differences in EC and cigarette use patterns between young people, but do not appear to influence longitudinal trajectories of EC and cigarette use within individuals. IMPLICATIONS: This study examined within- and between-person associations between e-cigarette use, cigarette use, and shared risk factors (alcohol use, marijuana use, mental health symptoms) in a longitudinal cohort of youths. Within- and between-person analyses revealed reciprocal prospective associations between e-cigarette and cigarette use, suggesting a progression toward more frequent use of both products over time. The shared risk factors examined here did not affect escalations in e-cigarette or cigarette use over time within individuals, but likely influence which youths use these products. Findings add to a growing body of evidence suggesting that e-cigarette use increases subsequent cigarette use in young people.

Long-term Associations Between Substance Use-Related Media Exposure, Descriptive Norms, and Alcohol Use from Adolescence to Young Adulthood.

Adolescents and young adults in the United States are constantly exposed to substance-related media and advertising content. The current study seeks to explore, developmentally, how exposure to substance-related media content influences both normative beliefs about peer alcohol use and individual alcohol use. Youth (N = 4'840; 50.6% female) were followed for ten years from age 12 to 22. Auto-regressive latent trajectory with structured residual (ALT-SR) models were used to explore within-person reciprocal associations between substance-related media content, descriptive norms, and alcohol use. Results indicated that' across adolescence and young adulthood, exposure to substance-related media content was associated with increased alcohol use via perceived alcohol norms. The pathway from media exposure to alcohol use was mediated by increased perceived norms for adolescents only. With screen time increasing over the last decade, it is important to invest resources into real-time interventions that address substance-related social media content as it relates to misperceived norms and to begin these interventions in early adolescence.

Sleepy Teens and Energy Drink Use: Results From an Ethnically Diverse Sample of Youth.

This study examines the association between use of energy drinks or products (EP), EP expectancies, and the association between EP use and sleep in a racially and ethnically diverse sample (N = 2,485) of adolescents. Prevalence of EP use was approximately 18%, with no statistically significant racial or ethnic differences in prevalence. There were significant racial and ethnic differences in EP expectancies; Hispanic and Multiracial or Other groups endorsed less positive expectancies than Whites and Asians. EP use was significantly associated with later weekend bedtimes, shorter weekend total sleep time (TST), a smaller weekend-weekday difference in TST, and more trouble sleeping, even after adjusting for covariates. There were no significant race or ethnicity interactions between EP use and sleep. EP use is an independent correlate of sleep problems in adolescents across racial or ethnic groups.