Adolescent use of illicit drugs other than marijuana: how important is social bonding and for which ethnic groups?

Birds of a Feather Get High Together: A Reconceptualization of the Social Bond with Latent Class Analysis and a Test with Different Forms of Drug Use

Social bond theory has received significant empirical support in examinations of drug use for decades. However, research utilizing the theory has often been fragmented and has not incorporated all four dimensions of the social bond. Additionally, much of this research has collapsed drug use into categories rather than examining specific forms of drug use. These concerns confuse the theoretical and practical insights that may be derived from such analyses. I utilize Monitoring the Future (2019) data to examine social bonding wholistically as latent classes in line with the concept of the social bond described by Hirschi (1969) and estimate the effect of the classes on specific forms of drug use. I find there are four distinct classes of social bonding among U.S. seniors most clearly differentiated by levels of attachment and commitment. Logistic regression results indicated different classes of social bonding were associated with different forms of drug use. I discuss the theoretical implications of the results and how they can be applied for criminal justice practitioners.

Biparental care in C57BL/6J mice: effects on adolescent behavior and alcohol consumption

RATIONALE

Social attachment plays an important role in offspring development. Different parenting experiences during lactation may shape offspring behavior and later alcohol use.

OBJECTIVES

We tested the hypothesis that differential rearing conditions (single mother, SM or biparental, BP) in the non-monogamous C57BL/6J mice may affect (1) parental behavior during lactation, (2) adolescent behavior, and (3) adolescent initiation of alcohol drinking.

METHODS

Mice were reared in SM or BP (cohabitation of father-mother since copulation) condition until weaning (postnatal day, PND, 21). Litters from both conditions were filmed during PNDs 6, 9, and 12 and an ethogram was made taking into account nest-, pup-, or self-directed behaviors. At PNDs, 28-29 adolescent animals were evaluated in a modified version of the concentric square field for measurement of behavioral patterns. Other groups of adolescents were tested in a 4-h daily, two-bottle choice alcohol consumption test (10% alcohol vs. water) during 3 weeks (4 days per week).

RESULTS

Single mothers spent less time in the nest, left unattended the nest more times, displayed more self-directed and less pup-directed behaviors than BP parents. SM-reared adolescents displayed more anxiogenic-like and less risk-associated behaviors than BP counterparts. The alcohol consumption test indicated a strong effect of rearing condition. Since the fifth day of test, SM adolescents consumed more quantities of alcohol than BP adolescents.

CONCLUSIONS

During single-mother parenting, pups are left unattended more often, and during adolescence, these organisms exhibited increased anxiety responses. This behavioral phenotype may act as a risk factor for alcohol initiation during adolescence.

Oxytocin, Tolerance, and the Dark Side of Addiction

Substance use disorders blight the lives of millions of people and inflict a heavy financial burden on society. There is a compelling need for new pharmacological treatments as current drugs have limited efficacy and other major drawbacks. A substantial number of animal and recent clinical studies indicate that the neuropeptide, oxytocin, is a particularly promising therapeutic agent for human addictions, especially alcohol use disorders. In preliminary trials, we found that oxytocin administered by the intranasal route, which produces some neuropeptide penetration into the CNS, potently blocked withdrawal and reduced alcohol consumption in heavy drinkers. A considerable body of earlier animal studies demonstrated that oxytocin inhibits tolerance to alcohol, opioids, and stimulants as well as withdrawal from alcohol and opioids. Based on these preclinical findings and our clinical results, we hypothesize that oxytocin may exert therapeutic effects in substance dependence by the novel mechanism of diminishing established tolerance. A newer wave of studies has almost unanimously found that oxytocin decreases self-administration of a number of addictive substances in several animal models of addiction. Reduction of established tolerance should be included among the potential explanations of oxytocin effects in these studies and changes in tolerance should be examined in future studies in relationship to oxytocin influences on acquisition and reinstatement of self-administration as well as extinction of drug seeking. Oxytocin efficacy in reducing anxiety and stress responses as well as established tolerance suggests it may be uniquely effective in reducing negative reinforcement (Koob's "dark side" of addiction) that maintains chronic substance use.

Alteration of adolescent aversive nicotine response and anxiety-like behavior in nicotine-exposed rats during late lactation period

Early nicotine exposure is an important cause of further habitual tobacco smoking. Although nicotine has not only rewarding but also aversive properties, the effects of early nicotine exposure on the distinct properties of nicotine are not well known. To reveal the effects of early adolescent nicotine exposure on further persistent tobacco smoking, we demonstrated developmental changes in nicotine-related appetitive and aversive behaviors of rats exposed to nicotine during the late lactation period. Sprague-Dawley rats were injected with saline or nicotine (2, 6 and 12mg/kg). We performed a two bottle free-choice test using escalating doses of nicotine (25, 50 and 100μg/ml), saccharin and quinine and the open field test in both adolescent and adult rats. The rats' aversive response to nicotine was increased according to the increase in nicotine concentration. Adolescent rats showed higher nicotine preference and consumption behaviors than did adult rats at an aversive dose of nicotine. Nicotine-exposed rats increased adolescent nicotine consumption when the nicotine concentration was 12mg/kg. We observed significant increases in anxious behaviors in adolescent nicotine-injected rats compared to saline-injected rats, but there were no alterations in adult rats. In both adolescent and adult rats, saccharin and quinine intake were not significantly different between groups. Taken together, it suggests that repeated nicotine exposure in late lactation period affect changes in aversive nicotine responses and anxious behaviors during adolescence but there is no difference in adults.

Differential effects of pair housing on voluntary nicotine consumption: a comparison between male and female adolescent rats

RATIONALE

Tobacco smoking occurs in a wide array of social circumstances. Social support for quitting is generally used to stop smoking, while peer interactions may be a crucial factor in triggering tobacco use among adolescents.

OBJECTIVES

To determine the role of social factors on nicotine dependence, we compared single- and pair-housed rats subjected to voluntary oral nicotine consumption tests.

METHODS

Six-week-old adolescent rats were subjected to experimental procedures and assigned to one of the following groups: a male single group, a male pair group with a sibling, a female single group, and a female pair group with a sibling. To measure voluntary nicotine intake, we adopted a two-bottle free-choice paradigm for each two days using 25 μg/ml and 100 μg/ml nicotine solution.

RESULTS

There were no differences in change in body weight or food intake between the two groups of either sex. Pair-housed female rats showed a reduction in nicotine consumption and preference for both low- and high-dose nicotine solution, while pair-housed male rats showed only reduced consumption and preference for high-dose nicotine solution, but not low-dose solution, as compared to single-housed male rats.

CONCLUSIONS

Nicotine consumption is sex-dependently controlled by the social circumstances of rats. This study broadens our perspectives on the role of social interactions as a therapeutic strategy to treat nicotine addiction-related behaviors depending on sex.

The Developmental Context of Substance use in Emerging Adulthood

The theory of emerging adulthood has been proposed as a way of conceptualizing the developmental characteristics of young people between the ages of 18 and 25. Here, the theory is applied to explaining the high rates of substance use in this age group. Specifically, five developmentally distinctive features of emerging adulthood are proposed: the age of identity explorations, the age of instability, the age of self-focus, the age of feeling in-between, and the age of possibilities. Then, each of these features is applied to an explanation of drug use in emerging adulthood.

Adolescent Predictors of Generalized Health Risk in Young Adulthood: A 10-Year Longitudinal Assessment

We conducted a prospective examination of multiple adolescent predictors of generalized health risk in early adulthood. Data were used from 3,392 members of a longitudinal cohort surveyed at ages 13 and 23. A measure of generalized risk was constructed using confirmatory factor analysis to represent shared variance among substance use, sexual risk, and victimization. Multiple regression analysis indicated several robust sociodemographic, behavioral, and environmental early predictors of generalized adult risk, including gender, age, race, not coming from a nuclear family, engaging in smoking and deviant behavior as an adolescent, having poor grades in high school, alcohol and cigarette use by an adult important to the adolescent, and being offered substances as an adolescent. Results support the existence of an underlying risk construct in early adulthood, the importance of early adolescent deviance and substance use exposure in predicting risk, and the use of early comprehensive interventions that prevent several risks simultaneously.

Neighborhood Context and Binge Drinking by Race and Ethnicity in New York City

BACKGROUND

Neighborhood context is associated with binge drinking and has significant health, societal, and economic costs. Both binge drinking and neighborhood context vary by race and ethnicity. We examined the relations between neighborhood characteristics--neighborhood norms that are accepting of drunkenness, collective efficacy, and physical disorder--and binge drinking, with a focus on examining race and ethnic-specific relationships.

METHODS

Respondent data were collected through 2005 random digit-dial-telephone survey for a representative sample of New York City residents; neighborhood data were based on the 2005 New York City Housing and Vacancy Survey. Participants were 1,415 past-year drinkers; Whites (n = 877), Blacks (n = 292), and Hispanics (n = 246). Generalized estimating equations were used to estimate population average models.

RESULTS

For the overall sample, neighborhood norms that were more accepting of drunkenness were associated with greater binge drinking (odds ratio [OR] = 1.22; 95% confidence interval [CI] = 1.09, 1.37); collective efficacy and physical disorder were not significant. However, when examining this by race/ethnicity, greater collective efficacy (OR = 0.75; 95% CI = 0.62, 0.91) and greater physical disorder (OR = 0.76; 95% CI = 0.62, 0.93) were associated with less binge drinking for Whites only. Neighborhood norms that were more accepting of drunkenness were associated with binge drinking among Whites (OR = 1.20; 95% CI = 1.05, 1.38) and, while not significant (perhaps due to power), the associations were similar for Hispanics (OR = 1.18; 95% CI = 0.83, 1.68) and slightly lower for Blacks (OR = 1.11; 95% CI = 0.67, 1.84).

CONCLUSIONS

Overall, results suggest that neighborhood characteristics and binge drinking are shaped, in part, by factors that vary across race/ethnicity. Thus, disaggregating data by race/ethnicity is important in understanding binge drinking behaviors.

Birth cohort effects on adolescent alcohol use: the influence of social norms from 1976 to 2007

CONTEXT The substantial changes in adolescent alcohol use prevalence over time suggest that population-level environmental factors are important determinants of use, yet the potential influence of such environmental factors is inadequately understood. OBJECTIVE To investigate whether adolescents in birth cohorts and/or time periods characterized by restrictive social norms toward alcohol were at decreased risk for alcohol use and binge drinking, controlling for individual attitudes (disapproval) toward use. DESIGN, SETTING, AND PARTICIPANTS In 32 annual national surveys of US high school students, a total of 967 562 students contributed outcome data from 1976 through 2007. MAIN OUTCOME MEASURES Frequency of past-year alcohol use and any instance of binge drinking (≥5 drinks) in the past 2 weeks, analyzed using multilevel models clustering individuals within periods and birth cohorts. Period- and cohort-specific social norm scores (indicating the proportion disapproving of weekend binge drinking) were modeled as predictors, controlling for individual attitudes and demographic characteristics. RESULTS Individuals who matured in birth cohorts with more restrictive social norms were less likely to use alcohol compared with individuals who matured in cohorts with more permissive norms; each 5% increase in the cohort-specific disapproval was associated with a 12% decrease in the odds of past-year alcohol use (odds ratio = 0.88; 99% CI, 0.87-0.89). The effects of cohort-specific disapproval were notably stronger among white adolescents than nonwhite adolescents. CONCLUSIONS This study documents the importance of considering time-varying population-level risk factors in the study of adolescent alcohol use and indicates that, even after an individual's personal attitudes are accounted for, risk is shaped by cohort effects whereby the norms within the cohort contribute to the risk of adolescent alcohol use.

Reinforcing properties of pups versus cocaine for fathers and associated central expression of Fos and tyrosine hydroxylase in mandarin voles (Microtus mandarinus)

The reciprocal interaction of pups and cocaine on reward effects in rodent mothers is known. However,it remains unclear whether such effects are apparent in father-offspring bonding. The mandarin vole (Microtus mandarinus) is a monogamous rodent with a high level of paternal care. We investigated the reinforcing properties of pups on vole fathers using a conditioned place preference paradigm across the postpartum period and looked for interactions and differences between the reinforcing effects of pups and cocaine. We also measured neuronal Fos and tyrosine hydroxylase (TH) expression underlying the preferences of fathers for pups or cocaine. Our data showed that fathers developed strong preferences for pups at various times (postnatal day 5–9, 13–17 and 19–23) without cocaine conditioning. Fathers showed a reduced preference for pups following simultaneous conditioning with cocaine. Although they preferred cocaine over postnatal day (PND) 5–9 pups, this preference was not detected for PND 13–17 pups. Fathers preferring cocaine exhibited an increase in Fos-immunoreactive neurons in the accumbens,medial nucleus of the amygdala, cingulate cortex, medial preoptic area and ventral tegmental area and had more TH-IR neurons in the ventral tegmental area compared to fathers preferring PND 5–9 pups. These results showed that similar to cocaine, mandarin vole pups elicit significant reward value to their fathers, but that paternal motivation is impaired by cocaine. A preference for cocaine over pups arose from the release of more dopamine and activation of a greater number of neurons within specific reward-associated neuronal subsets.

The social environment and neurogenesis in the adult Mammalian brain

Adult neurogenesis - the formation of new neurons in adulthood - has been shown to be modulated by a variety of endogenous (e.g., trophic factors, neurotransmitters, and hormones) as well as exogenous (e.g., physical activity and environmental complexity) factors. Research on exogenous regulators of adult neurogenesis has focused primarily on the non-social environment. More recently, however, evidence has emerged suggesting that the social environment can also affect adult neurogenesis. The present review details the effects of adult-adult (e.g., mating and chemosensory interactions) and adult-offspring (e.g., gestation, parenthood, and exposure to offspring) interactions on adult neurogenesis. In addition, the effects of a stressful social environment (e.g., lack of social support and dominant-subordinate interactions) on adult neurogenesis are reviewed. The underlying hormonal mechanisms and potential functional significance of adult-generated neurons in mediating social behaviors are also discussed.

Social bonding decreases the rewarding properties of amphetamine through a dopamine D1 receptor-mediated mechanism

Although the protective effects of social bonds on drug use/abuse have been well documented, we know little about the underlying neural mechanisms. Using the prairie vole (Microtus ochrogaster)--a socially monogamous rodent that forms long-term pair bonds after mating--we demonstrate that amphetamine (AMPH) conditioning induced a conditioned place preference (CPP) in sexually naive (SN), but not pair-bonded (PB), males. Although AMPH treatment induced a similar magnitude of dopamine release in the nucleus accumbens (NAcc) of SN and PB males, it had differential effects on NAcc D1 receptor (D1R) binding. Specifically, AMPH treatment increased D1R binding in SN, but decreased D1R binding in PB males. NAcc D1R, but not D2 receptor, antagonism blocked AMPH-induced CPP in SN males and NAcc D1R activation before AMPH conditioning enabled AMPH-induced CPP in PB males. Together, our data demonstrate that pair-bonding experience decreases the rewarding properties of AMPH through a D1R-mediated mechanism.

Associations between abstinence in adolescence and economic and educational outcomes seven years later among high-risk youth

AIM

In this study, we investigated the relationship between abstinence and long-term educational and economic outcomes among a sample of high-risk youth.

METHODS

Multivariable regression models were used to estimate associations between abstinence and outcomes among a sample of 13-17 year-olds referred to group homes in Los Angeles in 1999-2000 and followed for 87 months afterwards. Abstinence was measured during the first year of the study. We considered differential effects based on the duration of abstinence (12 vs. 6 months) and type of abstinence (all substances vs. use of alcohol and/or marijuana) on three 87-month outcomes: having received a high-school diploma or equivalent by age 20, institutionalization in the past 90 days, and total legitimate income for the past 90 days.

RESULTS

Abstinence from all substances for 12 months was associated with positive long-term educational and economic outcomes relative to using any drug during the same time interval. Abstaining from all substances for 12 months was also associated with an increased likelihood of being a legitimate wage earner and decreased likelihood of being institutionalized relative to using only alcohol and/or marijuana during that time interval. No effect on long-term outcomes was seen among youth who abstained for only 6 months relative to those who used drugs during this interval, or for youth who used only alcohol and/or marijuana over 12 months vs. those who used other drugs during this interval.

CONCLUSIONS

The results presented here justify continued and expanded efforts to promote long periods of abstinence from all drugs for high-risk youth.

Use and accidental exposure to hallucinogenic agents reported to the Czech Toxicological Information Centre from 1995 to 2008

Intoxication by hallucinogenic agents is relatively common in the Czech Republic, with most cases of the use of these agents being by adolescents and young people. The objective of the study was to evaluate the number, trends, gender and age of the subjects, and the severity of exposure in intoxication by hallucinogenic plant and mushroom substances, in comparison with synthetic drugs, brought to the attention of the Toxicological Information Centre (TIC) through inquiries over the past 14 years (1995-2008) (from total 3,702 calls concerning the use of both natural and synthetic drugs, 917 calls were due to the use of hallucinogenic plants and mushrooms).

The role of mesocorticolimbic dopamine in regulating interactions between drugs of abuse and social behavior

The use of addictive drugs can have profound short- and long-term consequences on social behaviors. Similarly, social experiences and the presence or absence of social attachments during early development and throughout life can greatly influence drug intake and the susceptibility to drug abuse. The following review details this reciprocal interaction, focusing on common drugs of abuse (e.g., psychostimulants, opiates, alcohol and nicotine) and social behaviors (e.g., maternal, sexual, play, aggressive and bonding behaviors). The neural mechanisms underlying this interaction are discussed, with a particular emphasis on the involvement of the mesocorticolimbic dopamine system.

School-related factors affecting high school seniors' methamphetamine use

Data from the 2005 Monitoring the Future survey were used to examine relationships between school-related factors and high school seniors' lifetime methamphetamine use. The study applied logistic regression techniques to evaluate effects of social bonding variables and social learning variables on likelihood of lifetime methamphetamine use. The results confirmed that likelihood of such use was higher when social bonding factors were weak and social learning factors were strong. Results also showed the social bonds' impact to be mediated by social learning factors. Policy implications are discussed briefly.

School effects on young people's drug use: a systematic review of intervention and observational studies

PURPOSE

This systematic review examined the hypothesis that school institutional factors influence young people's use of drugs. We aimed to (1) identify the effect of school-level changes on drug use and (2) explore the possible mechanisms by which school-level influences on individual drug use might occur.

METHODS

Systematic review. Experimental/quasi-experimental studies of "whole-school" drug prevention interventions and longitudinal observational studies on the association between school-level and individual-level school-related exposures and drug use were included. Experimental studies were included because they are the most reliable available source of evidence about causation. Observational studies of school-level and individual-level school-related exposures were included with the aim of providing evidence about a wider range of possible school-level effects and how school-level influences might be mediated by individual-level factors.

RESULTS

Experimental studies suggested that changes to the school social environment that increase student participation, improve relationships and promote a positive school ethos may be associated with reduced drug use. School-level and individual-level observational studies consistently reported that disengagement and poor teacher-student relationships were associated with drug use and other risky health behaviors.

CONCLUSIONS

There is evidence of school effects on young people's drug use. Interventions that promote a positive school ethos and reduce student disaffection may be an effective complement to drug prevention interventions addressing individual knowledge, skills, and peer norms. Such approaches should now be piloted in a wider range of settings. Further research is also needed to explore mechanisms by which schools may influence young people's drug use.

Amphetamine effects in microtine rodents: a comparative study using monogamous and promiscuous vole species

We compared amphetamine-induced dopamine release in the nucleus accumbens of vole species that exhibit differing mating systems to examine potential interactions between social organization and substance abuse. We found no species or regional differences in basal extracellular dopamine, however, monogamous voles had greater and longer-lasting increases in extracellular dopamine after amphetamine treatment than did promiscuous voles. We then examined whether amphetamine-induced increase in extracellular dopamine could induce pair bonds in monogamous voles. We found that, despite increasing dopamine in the nucleus accumbens, amphetamine administration did not induce pair-bonds in male prairie voles unless the animals were pretreated to preclude D1 receptor activation, which is known to inhibit pair-bond formation. These results support suggestions that social attachment and substance abuse share a common neural substrate.

Differences between Black and White elementary school children's orientations toward alcohol and cocaine: a three-study comparison

To trace the origins of race differences in substance use, this study examined differences between Black and White elementary school children's knowledge of alcohol and cocaine, beliefs about their short- and long-term effects, and attitudes toward and intentions to use them across three independent samples (N = 181, N = 287, N = 234). Black children were more negatively oriented toward alcohol and cocaine than White children from an early age. Most notably, in all samples Black children had less positive attitudes toward adult alcohol use and lower intentions to use alcohol. Black children were also more likely to attribute negative long-term health and social effects to alcohol and cocaine use, but there were few significant race differences in knowledge or in expectancies regarding short-term effects of use. Since race differences in beliefs, exposure to alcohol, and socioeconomic factors could not explain race differences in attitudes toward substance use, other cultural differences must be considered.

Does the economy affect teenage substance use?

This research examines how teenage drug and alcohol use responds to changes in the economy. In contrast to the recent literature confirming pro-cyclical alcohol use among adults, this research offers strong evidence that a weaker economy leads to greater teenage marijuana and hard-drug use and some evidence that a weaker economy also leads to higher teenage alcohol use. The findings are based on logistic models with state and year fixed effects, using teenagers from the NLSY-1997. The evidence also indicates that teenagers are more likely to sell drugs in weaker economies. This suggests one mechanism for counter-cyclical drug use - that access to illicit drugs is easier when the economy is weaker. These results also suggest that the strengthening economy in the 1990s mitigated what would otherwise have been much larger increases in teenage drug use.

Dopamine and monogamy

Social attachments play a central role in human society. In fact, such attachments are so important that deficits in the ability to form meaningful social bonds are associated with a variety of psychological disorders. Although mother-infant bonding has been studied for many years, we only recently have begun to examine the processes that underlie social bonds between adults. Over the past decade, central dopamine has become a focus of such research, especially its role in pair bonding between mates in species that display monogamous life strategies. Neuroanatomical and pharmacological studies in rodents have firmly established central dopamine systems, especially the mesocorticolimbic dopamine circuitry, in the formation, expression, and maintenance of monogamous pair bonds. As this research has progressed, it has become apparent that there is considerable overlap between the processes that underlie pair bonding and those that mediate responses to abused substances. This suggests that social bonding and substance abuse each may affect the other. Herein we review the current state of knowledge of central dopamine involvement in pair bond formation, expression, and maintenance. We first describe the neuroanatomical substrate within which dopamine exerts its effects on social bonding. We then describe dopamine receptor subtype-specific influences on pair bonding and how dopamine receptor activation may interact with activation of other neurochemical systems. Finally, we describe possible interactions between social bonding and substance abuse.

Youth gangs and drugs: the case of marijuana

While the association between drug sales and violence has been a central focus of gang research since the 1980s, the issue of drug use within gangs has been given much less attention. This is especially true in the case of marijuana. This lack of interest is surprising given the extent to which gang members use marijuana. Other than alcohol, marijuana is the most widely used substance in gang life. In examining the culture and role of marijuana in the lives of gang members, we highlight the integration and normalization of recreational drug use within their day-to-day activities and cultural practices. In doing so, we emphasize the similarity of the role of marijuana in gangs to its role in other youth groups. Data for this paper are drawn from the results of an on-going qualitative study of street gangs in the San Francisco Bay Area, in which 383 male gang members from three different ethnic groupings were interviewed.

Isolating the nexus of substance use, violence and sexual risk for HIV infection among young adults in the United States

Adults aged 18 to 29 are at significant sexual risk for HIV infection. Substance use and violence are known to be associated with sexual risk in certain groups, but few studies have examined these relationships in the general population of young adults. No studies have tested whether the contributions of substance use and violence to sexual risk are independent, and few have looked at whether drug use associations with risk are specific to certain substances. Using structural modeling techniques, we examined data for 3,437 adults aged 23-24, testing for associations between three measures of sexual risk for HIV, various forms of substance use, victimization and partner violence. Alcohol use and victimization predicted high risk sex in independent samples of single and married/cohabiting adults. Marijuana use, problem drug use, and partner violence were inconsistently related to sexual risk across measures and subsamples. HIV-prevention interventions designed for young adults in the general population should target individuals who use alcohol frequently and who are victims of violence, and should address both factors, in addition to sexual risk behavior.

Marijuana use and later problems: when frequency of recent use explains age of initiation effects (and when it does not)

Tobacco, alcohol, and marijuana are among the most commonly used drugs during adolescence. Initiation of marijuana use typically peaks at age 15, with risk of initiation continuing throughout adolescence. The goal of the current study was to prospectively examine the influence of age of marijuana initiation on four outcomes: physical health, mental health, illicit drug use other than marijuana, and marijuana-use related consequences at age 18. We controlled for several important predictors of adolescent drug use and its associated consequences, including demographics, social bonding variables, personality variables, and recent use of marijuana. Baseline survey data were collected in 1984 at grade 7 and follow up surveys were conducted at grades 8, 9, 10, and 12 (N = 2079). This initiates-only sample was 47% female, 66% White, 11% African American, 13% Hispanic, 5% Asian, and 5% other race or ethnicity. Findings indicated that age of initiation predicted marijuana consequences and other illicit drug use after controlling for demographic, social, and behavioral factors. However, once frequency of recent marijuana use was included in the models, age of initiation was only associated with other illicit drug use. Both primary and secondary prevention are needed to curb marijuana use and its associated harms.

Marijuana use from adolescence to young adulthood: multiple developmental trajectories and their associated outcomes

This study used latent growth mixture modeling to identify discrete developmental patterns of marijuana use from early adolescence (age 13) to young adulthood (age 23) among a sample of 5,833 individuals. After the a priori removal of abstainers, 4 trajectory groups were identified: early high users, who decreased from a relatively high level of use at age 13 to a more moderate level: stable light users, who maintained a low level of use: steady increasers, who consistently increased use; and occasional light users, who began use at age 14 and used at low levels thereafter. Analyses of covariance comparing the trajectory groups on behavioral, socioeconomic, and health outcomes at age 29 revealed that abstainers consistently had the most favorable outcomes, whereas early high users consistently had the least favorable outcomes.

Indices of lifetime polydrug use among adolescents

The functional equivalency for three indices of lifetime polydrug use was examined in a sample of adolescents (N = 794). The following indices were included in analyses: (a) a count of lifetime self-report of substances used; (b) an index weighted by the severity of the substances used; and (c) a hierarchical index of substance use. Analyses for each index was conducted twice with abstinent youth (no report of substances over their lifetime) included and excluded from analyses. Relationships between the indices with gender, age, ethnicity, and country of origin were examined. The only difference between the indices found was for ethnicity in the full sample. African Americans had higher scores on the hierarchical substance use index than Latinos or Asian/Pacific Islanders. With the exception of the relationship between the hierarchical index and ethnicity, the relationships between the other demographic variables with indices were consistent. Implications for utilizing the count or weighted index versus a hierarchical index of lifetime polydrug use are discussed.

[Drug use prevalence at FEBEM, Porto Alegre]

OBJECTIVE

This study aimed to determine the prevalence of drug use among institutionalized children and adolescents; to assess the degree of associated use of illicit drugs with alcohol and tobacco; and to determine which is the gateway drug to illicit drug use.

METHODS

A cross-sectional study was carried out in the Fundação Estadual do Bem-Estar do Menor, in Porto Alegre (FEBEM) Southern Brazil. A questionnaire developed by the World Health Organization to determine prevalence off drug use was answered anonymously by a population of literate minors who were in FEBEM because of delinquency or due to social risk. The analysis aimed to describe the frequency of use of each drug and relate it to gender, age of beginning, and reason of institutionalization.

RESULTS

A total of 382 participants answered the questionnaire. The substances most frequently used on an experimental basis were: alcohol (81,3%), tobacco (76,8%), marijuana (69,2%), cocaine (54,6%), inhalants (49,2%), anxiolytic drugs (13,4%), hallucinogens (8,4%), amphetamines (6,5%) and barbiturates (2,4%). Overall, around 80% of the respondents reported having used some illicit drug at least once in the past. Licit drugs, like alcohol and tobacco, were used mainly by males, while medicines were used mostly by females. Adolescents with delinquency records showed a significantly higher frequency of alcohol, marijuana, cocaine, and solvent use. The mean age of beginning was under 12 years for alcohol and tobacco use, under 13 years for marijuana and inhalants, and under 14 years for cocaine. Concomitant use of illicit and licit drugs was found to be high in this population.

CONCLUSIONS

A high prevalence of precocious drug use was found among institutionalized children and adolescent, with alcohol and tobacco being used earlier than illicit drugs. Delinquent males were more likely to have used illicit drugs.

From adolescence to young adulthood: racial/ethnic disparities in smoking

OBJECTIVES

We used data gathered from 6259 youths between the ages of 13 and 23 years to compare trends in smoking among 4 racial/ethnic groups.

METHODS

We weighted trend data to represent baseline respondent characteristics and evaluated these data with linear contrasts derived from multiple regression analyses.

RESULTS

Although African Americans exhibited higher initiation rates than Whites, they exhibited consistently lower rates of regular smoking than both Whites and Hispanics. This seeming anomaly was explained by African Americans' lower rates of transition to regular smoking and greater tendency to quit. Racial/ethnic disparities were accounted for by differences in pro-smoking influences.

CONCLUSIONS

Reducing racial/ethnic disparities in smoking may require reducing differences in the psychosocial factors that encourage smoking.

Explaining racial/ethnic differences in smoking during the transition to adulthood

Using data from a longitudinal panel of nearly 3000 adolescents to predict current smoking among young adults, we test whether adding variables that tap prior social bonds and influences to the model eliminates race/ethnicity as a significant predictor of current smoking. At age 23, African Americans and Asians exhibited substantially lower rates of current smoking than Whites and Hispanics. Controlling for social influences during high school, particularly exposure to siblings and friends who smoked plus parental disapproval of smoking, accounted for these differences. Social bonding variables, in contrast, had a limited mediating effect. Interventions aimed at decreasing adolescent vulnerability to prosmoking influences, reducing overall levels of peer cigarette use, and helping parents better convey their disapproval of smoking should help curb young adult smoking and diminish racial/ethnic differences in tobacco use.

A longitudinal study of the effects of adolescent cannabis use on high school completion

OBJECTIVE

To examine the extent to which weekly cannabis use during mid-adolescence may increase the risk of early school-leaving.

SETTING

A prospective study of a general population sample of adolescents studied from ages 15-21 years in Melbourne, Australia.

METHOD

Computer-assisted self-completion questionnaires and telephone interviews conducted in six waves at ages 15-18 and again at age 21 in a sample of 1601 male and female school students.

RESULTS

Weekly cannabis use, assessed prospectively, was associated with significantly increased risk of early school-leaving. This effect remained after adjustment for a range of prospectively assessed covariates including demographic characteristics, other substance use, psychiatric morbidity and antisocial behavior. There was suggestive evidence of an interaction between weekly cannabis use and age with the effects of weekly cannabis use on early school-leaving being strongest at the youngest ages and diminishing progressively with age.

CONCLUSIONS

Early regular cannabis use (weekly use at age 15) is associated with increased risk of early school-leaving. These effects of regular cannabis use may diminish with increasing age and are likely to operate through the social context within which cannabis is used and obtained.

Gender and ethnic differences in smoking, drinking and illicit drug use among American 8th, 10th and 12th grade students, 1976-2000

AIMS

This paper examines ethnic differences in licit and illicit drug use among American 8th, 10th and 12th grade students, with a particular focus on girls.

DESIGN

The study uses cross-sectional data from large, ethnically diverse, nationally representative samples of 8th, 10th and 12th grade girls.

SETTING

Data were collected through questionnaires administered in schools.

PARTICIPANTS

A total of 40 416 8th grade girls and 37 977 8th grade boys, 35 451 10th grade girls and 33 188 10th grade boys, and 33 588 12th grade girls and 31 014 12th grade boys took part in the study.

FINDINGS

Across ethnic groups, drug use is highest among Native American girls and lowest among black and Asian American girls. Trend data suggest that there have been important changes in girls' drug use over time and that girls' and boys' drug use patterns are converging.

CONCLUSIONS

Drug use is widespread among American adolescent girls. Future research should examine further girls' drug use and seek to identify whether risk and protective factors identified in past research, based on predominantly white samples, are also important predictors for drug use among non-white girls.

Does elementary school alcohol, tobacco, and marijuana use increase middle school risk?

PURPOSE

To assess whether alcohol, tobacco, and other drug (ATOD) use in elementary school may have serious implications for continued ATOD use in middle school and beyond.

METHODS

Longitudinal analyses were conducted on questionnaire data from 331 middle school students who had previously provided ATOD-use data during elementary school. Non-school personnel administered questionnaires in three participating school districts in three different states. The sample of students was ethnically and geographically diverse, including students from a range of low socioeconomic status backgrounds living in rural, urban or inner-city environments.

RESULTS

Middle school alcohol use was almost three times as likely to occur if alcohol use had occurred in elementary school (OR = 2.94, p <.001). Elementary school use of tobacco and marijuana also greatly increased the likelihood of middle school use (OR = 5.35, p <.001 and OR = 4.25, p <.05, respectively).

CONCLUSIONS

Early use of ATOD is associated with greatly increased odds of later use, which has important implications for the timing of drug prevention programs. Preventive interventions designed for use in pediatric practice settings should commence no later than elementary school, during the middle childhood years.

Heavy cannabis use among UK teenagers: an exploration

Findings are presented from a survey of a sample of 2641 UK school students aged 15--16 years. This exercise was part of the 30 country European School Survey Project on Alcohol and other Drugs (ESPAD). The 201 students who reported using cannabis (marihuana) 40 times or more were examined using cluster analysis. They were also compared to other students. Three clusters of heavy cannabis users emerged. The smallest was largely distinguished by antisocial behaviour. Another cluster were clearly unhappy, with little support from parents and friends, high levels of depressed mood and low levels of self-esteem. The largest cluster were 'ordinary' and had little to distinguish them apart from a belief that their environment was stable and predictable and that society's rules should be obeyed. Although clear relationships emerged between heavy cannabis use and heavy use of other substances, the 'ordinary' cluster of heavy cannabis users were less likely than the others to have used other illicit drugs. It is therefore concluded that teenage heavy cannabis users have varied motivations and contexts for their usage. They should not be seen as a homogeneous group and many do not appear to use other illicit drugs.

Cross-cultural surveys of adolescent health and behavior: progress and problems

Adolescent health surveys administered in different countries or regions often are described as cross-cultural. Although most include youth of different ethnic and cultural groups, few attempt to define these constructs or to collect data that allow their characterization. This paper explores four challenges shared by large-scale surveys of adolescent health-related behaviors and beliefs. First, adolescent health investigators have used the terms culture and ethnicity loosely. The growing interest in contextual analysis demands standardization of the definitions as they apply to adolescents, followed by correct usage of the terms. Hypotheses regarding the associations between race, ethnicity, culture, health-related behaviors, and health outcomes should be clearly stated and incorporated into conceptual models. Second, cross-cultural analyses are interpretable only when the study designs and sampling methods provide adequate representation of cultural and ethnic minorities and when the survey items allow differentiation of factors related to race, ethnicity, culture, and socioeconomic factors. Third, cross-cultural research may expose traditions, beliefs, and behaviors that are supported by one population yet criticized by another. Investigators must recognize their own personal biases and must work collaboratively to analyze and interpret their data correctly. Fourth, generalizations about cultural/ethnic comparisons can evoke powerful emotional reactions. Interpretation and dissemination of research findings should be done sensitively and with the help of experts from the cultural/ethnic groups that have been studied.

Effects of incentive size and timing on response rates to a follow-up wave of a longitudinal mailed survey

Young adults who had previously participated in a longitudinal survey of youth were sent a questionnaire. They were randomly assigned to receive a $20 prepayment, a $20 postpayment, or a $25 postpayment for participation in the latest survey. Those in the large incentive condition were 7 percentage points more likely to return a survey than those in the smaller, postpayment group. Prepayment had a smaller, less reliable effect. Effects of incentive magnitude and timing were consistent at each month of the study period; only better high school grades distinguished early responders from late responders. Nonresponders had characteristics suggestive of low social conformity and were more likely than responders to be African American and male and have low SES. The discussion centers on motivations for participating in research and differences in the incentives likely to promote continued response versus initial study enrollment.

Simultaneous polydrug use among teens: prevalence and predictors

The use of two or more substances in combination, simultaneous polydrug use (SPU), is a particularly dangerous form of drug use that appears to be established by late adolescence. We examined the prevalence of SPU in a diverse sample of 12th graders, and identified risk and protective factors for SPU that are present at 10th grade. We also tested for differences in SPU across race and gender, and explored the basis for observed differences. Our goals were to determine the extent of SPU problems in different groups and how to address these problems. Twenty-nine percent of participants had engaged in SPU in the past year. The best predictors of alcohol/marijuana SPU were a pro-drug environment, pro-drug beliefs, social deviance, and family disruption; only a pro-drug environment was predictive of hard drug SPU. Women were far less likely to combine marijuana and alcohol than were men. Asian Americans were less likely to combine alcohol and marijuana than were other racial groups, apparently due to their advantaged standing on all predictors of this behavior. African Americans were less likely to use hard drugs in combination than were other groups. Overall, polydrug use is a substantial problem for older teens. Broader drug-use prevention programs may be sufficient to address SPU involving gateway drugs, but reducing drug availability appears central to addressing hard drug SPU.