Opportunities to use drugs and stages of drug involvement outside the United States: Evidence from the Republic of Chile

Gender differences in illicit drug access, use and use disorder: Analysis of National Survey on Drug Use and Health data

Although gender differences in the prevalence of substance use disorders (SUD) have been well-characterized, little is known about when gender differences emerge along the continuum of substance use. Understanding the contribution of gender to risk at key transition points across this continuum is needed to identify potential mechanisms underlying gender differences and to inform improved gender-responsive interventions. To characterize gender differences in the progression of cannabis, cocaine, and heroin use, the current study used data from the United States-based 2015-2019 National Survey on Drug Use and Health to quantify gender differences in: (1) perceived access to drugs, (2) lifetime drug use among individuals with at least some access, and (3) past-year SUD among those who had ever used each drug. Logistic regressions were conducted for each drug to examine gender differences across all three stages, controlling for sociodemographic factors and survey year. Compared to women, men had higher odds of reporting access to and lifetime use of all three drug types. Men also had higher odds of past-year cannabis and cocaine use disorders compared to women. Results suggest gender differences emerge in the earliest stage of drug use (access) and may accumulate across the stages of use. The magnitude of gender differences varied across stages, with the largest differences observed for odds of drug initiation among those with perceived access to each drug. Longitudinal data will be needed to confirm these findings and to provide insight into potential contributors to gender-specific risk and intervention targets across the continuum of drug use severity.

Perceived Neighbourhood Disorder, Alcohol Consumption and Alcohol-Related Problems in Chile

Background: Alcohol misuse is one of the most important preventable public health risk factors. Empirical research shows that alcohol misuse is related to social and economic losses. Both theoretical and empirical evidence suggests that neighborhood disorder impacts alcohol-related behavior. However, there is limited literature in the context of developing countries. Objectives: The aim of this research is to estimate the association between perceived neighborhood disorder and (1) alcohol-related behavior and (2) alcohol-related problems in the context of the Chilean population. Our contribution focuses on the examination of the perception of disorder in urban neighborhoods and alcohol use patterns in a wide age range and sample of Chilean cities. Results: High levels of neighbor disorder perception are associated with higher levels of drinking and hazardous alcohol use. In addition, perceived neighborhood disorder is directly associated with probability of alcohol-related problems (ranging from 2% to 11%). Conclusions/Importance: The results are consistent with empirical and theoretical frameworks. This research could be used to better guide place-based policies in emerging countries with high levels of alcohol consumption to prevent alcohol risk behaviors and alcohol-related problems.

Insomnia as a Risk Factor for Substance Use Disorders in Women

Gender differences exist for both insomnia and substance use disorders. Women show a higher prevalence of insomnia and increased susceptibility to the effects of drugs than men. Importantly, a growing body of evidence suggests that insufficient sleep predicts and puts individuals at a higher risk for substance use and associated psychosocial problems. However, the role of insomnia in substance use disorders among women remains poorly understood. The present article discusses gender differences in insomnia and in substance use disorders and reviews evidence suggesting that an increased prevalence of insomnia may be a risk factor for substance use disorders in women.

Association Patterns of Antisocial Personality Disorder across Substance Use Disorders

There is a high prevalence of antisocial personality disorder (ASPD) in individuals affected by substance use disorders (SUD). However, there is limited information on the specific patterns of association of ASPD with SUD severity and specific SUD diagnostic criteria. We investigated the association of alcohol, cannabis, cocaine, opioid, and tobacco use disorders (AUD, CanUD, CocUD, OUD, and TUD, respectively) in 1,660 individuals with ASPD and 6,640 controls matched by sex (24% female), age, and racial/ethnic background in a sample ascertained for addiction-related traits. Generalized linear regressions were used to test the association of ASPD with the five DSM-5 SUD diagnoses, their severity (i.e., mild, moderate, severe), and their individual diagnostic criteria. We found that ASPD is associated with the diagnosis and severity of AUD (Odds Ratio, ORs=1.89 and 1.25), CanUD (ORs=2.13 and 1.32), and TUD (ORs=1.50 and 1.21) ( ps <.003). Of the specific diagnostic criteria, the "hazardous use" criterion showed the strongest association with ASPD across the five SUDs investigated (from OR TUD =1.88 to OR CanUD =1.37). However, when criteria of different SUDs were included in the same model, ASPD was independently associated only with TUD "hazardous use" and CocUD "attempts to quit". Attempting to quit cocaine was inversely related to the presence of ASPD and remained significant (OR=0.57, 95% confidence interval = 0.36-0.89) after controlling for interactive effects with sex. The current work provides novel insights into how different SUDs, their severity, and their diagnostic criteria associate with ASPD, potentially furthering our understanding of the impact of polysubstance addiction on mental health.

Early-life trauma, negative and positive life events, compulsive sexual behavior disorder and risky sexual action tendencies among young women with substance use disorder

Although significant advances have been made in the field to date, gender-based issues for women remain a neglected area in much of substance abuse research. In the current study we examined two gaps in the literature: the co-occurrence of compulsive sexual behavior disorder (CSBD) and risky sexual action tendencies among women with substance use disorders (SUDs), and their shared antecedents in the form of early life adversity and negative life events. The sample comprised 132 women of whom 62 had substance use disorder (drug and alcohol) and 70 were healthy controls. Each participant completed self-report measures of drug abuse and alcoholism, compulsive sexual behavior disorder and risky sexual action tendencies as well as early-life trauma and negative and positive life events. Results indicate that young women with substance use disorder have higher compulsive sexual behavior disorder symptoms and more prevalent risky sexual action tendencies than controls. Compulsive sexual behavior was also found to mediate the association between substance use and risky sexual action tendencies. In addition, all addictive behaviors were linked with emotional abuse at childhood but not with other types of abuse. Conversely, negative life events in adulthood were only linked with CSBD and not with substance use. The findings provide deeper insights into the comorbidity of addictive behaviors and an opportunity for developing more effective treatments for women who suffer from these addictions.

Variations in risk and promotive factors on substance use among urban American Indian youth

Although roughly 70% of the American Indian and Alaska Native (AI) population live in urban areas, research is scarce regarding this population. As a consequence, there is limited understanding about the salient socioenvironmental factors that aid in preventing substance use among urban AI communities. This study utilized a statewide, cross-sectional, school-based survey of urban AI adolescents (N = 2,375) to (a) examine the associations between substance use and risk and promotive factors within the family and peer group, and (b) explore how these associations vary by subgroups (gender, racial/ethnic background, and grade level). Results suggest that risk factors-familial substance use and antisocial peer affiliation-were associated with higher alcohol, cigarette, and marijuana use. However, these findings varied by subgroup. For males, involvement with antisocial peers was associated with greater marijuana use. Involvement with antisocial peers was also positively associated with alcohol and marijuana use for multiracial/multiethnic AI adolescents and those adolescents in 10th and 12th grades. The promotive factors-supportive family environment and prosocial peer affiliation-were not universally associated with lowered substance use by subgroup. This study advances understandings of the risk and promotive factors important in reducing and preventing substance use among urban AI adolescents. Experiencing familial substance use and affiliating with antisocial peers were the salient factors associated with increased substance use, particularly for urban AI adolescents who are older, male, and with multiracial/multiethnic AI backgrounds.

Adolescent Substance Use and the Brain: Behavioral, Cognitive and Neuroimaging Correlates

Adolescence is an important ontogenetic period that is characterized by behaviors such as enhanced novelty-seeking, impulsivity, and reward preference, which can give rise to an increased risk for substance use. While substance use rates in adolescence are generally on a decline, the current rates combined with emerging trends, such as increases in e-cigarette use, remain a significant public health concern. In this review, we focus on the neurobiological divergences associated with adolescent substance use, derived from a cross-sectional, retrospective, and longitudinal studies, and highlight how the use of these substances during adolescence may relate to behavioral and neuroimaging-based outcomes. Identifying and understanding the associations between adolescent substance use and changes in cognition, mental health, and future substance use risk may assist our understanding of the consequences of drug exposure during this critical window.

Modelling opportunity: An examination of quadratic effects of adolescent Venezuelan substance use

INTRODUCTION AND AIMS

Numerous studies have found a linear relationship between an exposure opportunity and age of first drug use. This study further tests this relationship by exploring whether a quadratic exposure opportunity best fits the data on age of first use and whether gender moderates this relationship. That is, is there a peak age in which the transition to use occurs for male compared to female adolescents?

DESIGN AND METHODS

A sample of 1716 adolescents from 14 public and private schools, representative of two school districts in Caracas, Venezuela, was examined using a zero-inflated Poisson modelling approach to test for quadratic effects. A series of models were tested for each set of substances (alcohol, tobacco and other drugs) to assess whether a quadratic model has better predictive ability than linear models and to test whether gender moderates the quadratic relationship.

RESULTS

After controlling for common covariates, the quadratic models for alcohol indicated the peak age of transition from an exposure opportunity to use was 10-years of age in this Venezuelan sample. Gender did not moderate these models suggesting an important move toward gender equality in substance use.

DISCUSSION AND CONCLUSIONS

Focused efforts on preventing exposure to alcohol use during these windows of rapid transition is likely to have the greatest impact on delaying age of onset, which will reduce the overall prevalence of alcohol related problems among adolescents.

Factors associated with tobacco, alcohol, and other drug use among youth living in West Central Mexico

AIM

To determine the prevalence of drug and substance abuse among high school students in Jalisco and its association with the severity of health, behavior and psychosocial problems in order to provide evidence for possible prevention and treatment needs.

METHODS

A multi-stage random sample of Jalisco high school students was given a paper-and-pencil survey based upon an adapted version of the drug use screening inventory (DUSI) (n = 24699; n = 2832). The DUSI showed adequate psychometric characteristics in this population. The statistical analyses accommodated the complex survey design with attention to unequal probability of selection and clustering of participants within schools and regions.

RESULTS

An estimated 44% of the students had smoked tobacco, one in five students was a current smoker, and one in four students used to smoke but had not smoked for one year or more. By contrast, 6.8% of the students reported having used marijuana, cocaine, or both. Behavioral problems, deviant peer affiliation, and troubled families were independently associated with drug use. One in two students who used tobacco or alcohol had used these drugs in the past year (46% and 54%, respectively), and one in four students who used marijuana or cocaine in their lifetime had used those drugs in the past year (28% in both cases).

CONCLUSION

The rates of cocaine use as well as the proportion of current users were higher than expected among high school students and indicate changing patterns of drug use in Mexico. These results corroborate that the general trend of drug use by youth in Mexico is increasing. Results from this study help us better understand the needs of at-risk youth and the need for new treatment and prevention strategies.

Trends in drug offers among adolescents in the United States, 2002-2014

BACKGROUND

Being offered illicit drugs is a critical factor leading to drug initiation and other psychosocial risk behaviors among adolescents in the United States. However, there exist few studies examining the recent trends in drug offers among adolescents, particularly across racial/ethnic subgroups. The present study examines trends and psychosocial/behavioral correlates of drug offers among adolescents of the three largest racial/ethnic groups.

METHODS

We used data from the 2002-2014 National Survey on Drug Use and Health of adolescents aged 12-17, which include African-American, Hispanic, and White adolescents (n = 199,700) in the U.S. We estimated the prevalence of past-month drug offers by race/ethnicity, and conducted logistic regression analyses to test the significance of the trends and to examine the correlates of drug offers.

RESULTS

Overall, the prevalence of drug offers decreased significantly from 16.3% in 2002 to 12.3% in 2014, reflecting a 24.5% reduction in the relative proportion of adolescents who were offered drugs. While the decreasing trends were observed in all subgroups (e.g., race/ethnicity), the decreases were more limited among African-American and Hispanic youth than White youth. As a result, while no differences were observed at the outset of the study, a higher proportion of African-American and Hispanic adolescents were offered drugs between 2012 and 2014.

CONCLUSIONS

Findings suggest a general decline in drug offers among adolescents in the U.S., but racial/ethnic differences in prevalence were identified. This underscores the importance of further efforts to understand the racial/ethnic differences in drug offers and suggests the need for culturally-sensitive drug prevention programs.

Sex and gender differences in substance use disorders

The gender gap in substance use disorders (SUDs), characterized by greater prevalence in men, is narrowing, highlighting the importance of understanding sex and gender differences in SUD etiology and maintenance. In this critical review, we provide an overview of sex/gender differences in the biology, epidemiology and treatment of SUDs. Biological sex differences are evident across an array of systems, including brain structure and function, endocrine function, and metabolic function. Gender (i.e., environmentally and socioculturally defined roles for men and women) also contributes to the initiation and course of substance use and SUDs. Adverse medical, psychiatric, and functional consequences associated with SUDs are often more severe in women. However, men and women do not substantively differ with respect to SUD treatment outcomes. Although several trends are beginning to emerge in the literature, findings on sex and gender differences in SUDs are complicated by the interacting contributions of biological and environmental factors. Future research is needed to further elucidate sex and gender differences, especially focusing on hormonal factors in SUD course and treatment outcomes; research translating findings between animal and human models; and gender differences in understudied populations, such as those with co-occurring psychiatric disorders and gender-specific populations, such as pregnant women.

Ready, willing, and able: the role of cannabis use opportunities in understanding adolescent cannabis use

AIMS

To examine adolescent cannabis use-both at national and individual levels-by deconstructing it into its necessary conditions of realistic use opportunities and willingness to use the drug given such opportunities.

DESIGN

Nationally representative, repeated cross-sectional survey.

SETTING

Norway.

PARTICIPANTS

A total of 8818 16-year-olds who participated in the European School Survey Project on Alcohol and Other Drugs (ESPAD) in 2007, 2011, and 2015.

MEASUREMENTS

Adolescent reports concerning their life-time 'cannabis use' and 'possibilities to use cannabis' were used to assess: (a) overall cannabis use, (b) exposure to realistic cannabis use opportunities, and (c) cannabis use among those exposed to use opportunities. Logistic regression models were used to estimate national trends since 2007 in these indicators, and to identify individual-level factors associated with cannabis use versus non-use among youth exposed to concrete use opportunities.

FINDINGS

Prevalence of life-time cannabis use remained stably low, averaging 6.4% across the three surveys. Life-time exposure to cannabis use opportunities decreased [odds ratio (OR)_{ESPAD assessment}  = 0.90, 95% confidence interval (CI) = 0.84-0.97, P = 0.006], yet cannabis use among adolescents with such opportunities increased significantly (OR_{ESPAD assessment}  = 1.17, 95% CI = 1.03-1.34, P = 0.02) since 2007. After controlling for a range of other risk factors, abstinence from alcohol intoxication and cigarette use, as well as the perceptions of even minimal cannabis use as risky remained the factors most robustly associated with lower likelihood of cannabis use among youth with realistic use opportunities.

CONCLUSIONS

Approaches accounting for realistic use opportunities proved critical in our understanding of underage cannabis use, both at the national and individual level, and may be informative for development of prevention strategies in the era of cannabis liberalization. In addition, delineation of realistic opportunities from behaviours conditioned upon such opportunities is generalizable to a range of public health issues.

In-transition culture of experimentation with cannabis in Latin American college students: A new role within a potential drug use sequencing pattern

INTRODUCTION AND AIMS

Given a scenario of intense discussion about the legal situation of cannabis users worldwide, this paper aims to investigate the role of cannabis within a drug use sequencing pattern.

DESIGN AND METHODS

Data came from a representative sample of college students from 27 Brazilian capitals (n = 12 711). We analysed the patterns of transition from/to the first use of cannabis to/from the first use of alcohol, tobacco and seven other illegal drugs. Survival analysis methods were used to analyse age of onset data on all potential drug pairs. Drugs that were not specified as the target drug pair tested in each survival model were included as time-varying covariates in all models.

RESULTS

We found significant transitions from alcohol [adjusted hazard ratio (aHR) = 1.41, 95% confidence interval (CI) 1.15-1.73, P < 0.001] and inhalants (aHR = 1.56, 95% CI 1.26-1.93, P < 0.001) to cannabis. Moreover, we found significant transitions from cannabis to alcohol (aHR = 2.40, 95% CI 1.47-3.91, P < 0.001), cocaine (aHR = 7.47, 95% CI = 4.26-13.09, P < 0.001), prescription opioids (aHR = 2.16, 95% CI 1.29-3.63, P < 0.01) and tranquilisers (aHR = 1.51, 95% CI 1.11-2.06, P < 0.01).

DISCUSSION AND CONCLUSIONS

Overall, our findings point to a strategic role of cannabis within drug first use sequence pattern. We had an important and unexpected finding-the bi-directional relationship between alcohol and cannabis. In addition, the first use of cannabis still precedes the first use of cocaine and non-medical use of tranquilisers and prescription opioids. [Castaldelli-Maia JM, Nicastri S, Cerdá M, Kim JH, Oliveira LG, Andrade AG, Martins, SS. In-transition culture of experimentation with cannabis in Latin American college students: A new role within a potential drug use sequencing pattern. Drug Alcohol Rev 2017;00:000-000].

Drug involvement during and after college: Estimates of opportunity and use given opportunity

BACKGROUND

College students perceive widespread availability of drugs and prescription medications for non-medical use on campus, but less is known about the relationship between opportunity to use, use, and use given opportunity of these drugs during and after college. The current study describes annual trends in (1) opportunity to use, (2) use, and (3) use given opportunity of eight drugs and three prescription medications used non-medically over seven years.

METHODS

Data were derived from a longitudinal cohort study of 1253 first-year college students (52% female, 72% non-Hispanic white) at one large, public university. Annually, past-year opportunity to use and use were assessed for marijuana, hallucinogens, inhalants, cocaine, ecstasy, amphetamines, methamphetamine, heroin, and non-medical use of prescription stimulants, analgesics, and tranquilizers. Binary variables were created to represent opportunity to use, use, and use given opportunity for each drug.

RESULTS

Participants had the greatest opportunity to use marijuana compared with other drugs during the study period, but there was a significant decline in the opportunity to use marijuana over time. Notably, opportunity for both drugs other than marijuana and prescription medications used non-medically consistently declined, while use given opportunity remained relatively stable over time.

CONCLUSIONS

These findings suggest that changes in drug use are driven by changes in opportunity to use, even during the post-college years. Greater opportunity to use and use of all drugs during the college years in comparison with the post-college years confirms the high-risk nature of the college environment.

Who are the adolescents saying "No" to cannabis offers

BACKGROUND AND AIMS

Adolescents who refuse direct cannabis offers and remain non-users represent a potentially very informative, yet surprisingly understudied group. We examined a range of risk and protective factors putatively associated with this poorly understood "cannabis-resilient" profile.

METHODS

Paper-and-pencil questionnaires assessing substance use, peer and family relations, and behavioral and personality characteristics were completed by 19,303 middle- and high-school students from 82 schools in Norway (response rate 84%)

RESULTS

The lifetime prevalence of cannabis use was 7.6%. Another 10.4% reported no use of the drug despite having received recent cannabis offers. Results from the multinomial logistic regression revealed a set of characteristics differentiating adolescents who resisted such offers from those who: (a) neither received the offers nor used, and, more importantly, (b) used the drug. Specifically, parent-child relationship quality, negative drug-related beliefs, absence of close relationships with cannabis-users, low delinquency, no regular tobacco use, and infrequent alcohol intoxication were all associated with increased odds of being in the cannabis-resilient vs. cannabis-user group. This pattern of results was comparable across middle- and high-school cohorts, but the parent-child relationship quality and delinquency were significantly associated with cannabis-resilient vs. cannabis-use outcome only among younger and older adolescents, respectively.

CONCLUSIONS

Among other low-risk characteristics, better relationships with parents and beliefs that drug use is problematic were associated with adolescents' refusals to accept cannabis offers. These results may have implications for novel preventive strategies targeting cannabis-exposed adolescents.

Opportunities to use drugs and the transition to drug use among adolescents from Caracas, Venezuela

Few studies have examined exposure to drug use and the lag between exposure and use. This paper estimates prevalence of opportunity to use a substance, for use, and for use given an opportunity to use among a sample of Venezuelan adolescents. Several covariates on the opportunity to use and the transition to use are also examined. Findings show that lifetime prevalence of substance use among Venezuelan adolescents increases dramatically and more closely resembles rates among US and European samples when having had an opportunity to use was taken into account. A majority of youth who transitioned to use did so the same year exposure occurred, and females had a shorter time difference compared to males. Covariates primarily predicted exposure rather than having used after controlling for exposure, and their effects varied by substance. Implications for prevention efforts are discussed.

Onset of opportunity to use cannabis and progression from opportunity to dependence: Are influences consistent across transitions?

BACKGROUND

There is a developing body of research looking at cannabis use opportunity, but little research examining timing of opportunity to use cannabis.

AIMS

Identify factors associated with (1) earlier opportunity to use cannabis and (2) faster progression from opportunity to cannabis dependence.

METHOD

Cross-sectional study of 3824 Australian twins and siblings, measuring age of onset of cannabis use opportunity and DSM-IV cannabis dependence. Survival analysis identified factors associated with faster progression to opportunity or dependence.

RESULTS

Factors associated with both speed of progression to opportunity and dependence were conduct disorder (opportunity HR 5.57, 95%CI 1.52-20.47; dependence HR 2.49, 95%CI 1.91-3.25), parental drug problems (opportunity HR 7.29, 95%CI 1.74-30.62; dependence HR 3.30, 95%CI 1.63-6.69), weekly tobacco use (opportunity HR 8.57, 95%CI 3.93-18.68; dependence HR 2.76, 95% CI 2.10-3.64), and female gender (opportunity HR 0.69, 95%CI 0.64-0.75; dependence HR 0.44, 95%CI 0.34-0.55). Frequent childhood religious attendance (HR 0.74, 95%CI 0.68-0.80), parental conflict (HR 1.09, 95%CI 1.00-1.18), parental alcohol problems (HR 1.19, 95%CI 1.08-1.30) and childhood sexual abuse (HR 1.17, 95%CI 1.01-1.34) were uniquely associated with transition to opportunity. Depressive episode (HR 1.44, 95%CI 1.12-1.85), tobacco dependence (HR 1.36, 95%CI 1.04-1.78), alcohol dependence (HR 2.64, 95%CI 1.53-4.58), other drug use (HR 2.10, 95%CI 1.64-2.69) and other drug dependence (HR 2.75, 95%CI 1.70-4.43) were uniquely associated with progression to dependence.

CONCLUSION

The profile of factors associated with opportunity to use cannabis and dependence only partially overlaps, suggesting targeting of interventions may benefit from being tailored to the stages of drug use.

Who receives cannabis use offers: A general population study of adolescents

BACKGROUND

Drug use is predicated on a combination of "willingness" and "opportunity". That is, independent of any desire to use drugs, a drug use opportunity is required; be it indirect (i.e., being in a drug-use setting) or direct (i.e., receiving a direct drug offer). However, whether some youth are more likely to encounter such direct drug use opportunities is not fully known.

AIMS

We examined whether certain characteristics placed adolescents at greater risk for being offered cannabis, after accounting for a number of demographic-, contextual-, interpersonal-, and personal-level risk factors.

METHODS

We utilized data from a Norwegian school survey (n=19,309) where the likelihood of receiving cannabis offer in the past year was estimated using logistic regression models. Substantive focus was on the individual and combined effects of personal (i.e., delinquency) and interpersonal (i.e., cannabis-using close friend) risk factors. Separate models were fit for middle- and high-school students.

RESULTS

Delinquency was a significant risk factor for receiving cannabis offers, as was a cannabis-using best friend. In addition, peer cannabis use increased the risk of cannabis offers mostly for adolescents on the lower delinquency spectrum, but less so for highly delinquent adolescents. These interaction effects were primarily driven by the middle-school cohort.

CONCLUSIONS

Cannabis offers were more likely to be extended to youth of certain high-risk profiles. Targeted prevention strategies can therefore be extended to a general profile of younger adolescents with externalizing problems and cannabis-using peers.

Prevalence and determinants of resistance to use drugs among adolescents who had an opportunity to use drugs

BACKGROUND

As drugs remain ubiquitous and their use increasingly viewed as socially normative, vulnerable population groups such as adolescents face continued and growing risk. A better understanding of the factors that discourage individuals from initiating drug use, particularly in enabling scenarios, is therefore needed. This study aims to identify individual, interpersonal and school-contextual factors associated with resistance to using drugs in the presence of a drug use opportunity among adolescents in Bogotá, Colombia.

METHODS

Data are analyzed from 724 school-attending adolescents (15.1 years, SD=1.3) who have had an opportunity to use drugs. Schools were selected in a multistage probability cluster sample. Random intercept multilevel logistic regression models were implemented to estimate the effect of individual, interpersonal and school-contextual level variables on the likelihood of resisting using drugs.

RESULTS

Drug use resistance was observed in less than half (41.4%) of those students who experienced an opportunity to use drugs. Drug use resistance was strongly associated with having experienced a passive drug use opportunity (AOR = 3.1, 95% CI = 2.0, 4.9), the number of drugs offered (AOR = 0.7, 95% CI = 0.6, 0.8) and family factors such as not having a drug-using first-degree relative (AOR = 2.3, 95% CI=1.2, 4.3) and a high degree of parental supervision (AOR = 1.9, 95% CI = 1.0, 3.2).

CONCLUSIONS

A large proportion of students who experienced a drug-use opportunity did not initiate drug use despite living in a context of high drug availability and social disorganization. The findings highlight the need for effective family-based drug use prevention interventions within the Colombian context.

The role of first use of inhalants within sequencing pattern of first use of drugs among Brazilian university students

The present study investigated the role of first use of inhalants within a first drug sequencing pattern. In a representative sample of university students from 27 Brazilian capitals (n = 12,711), we analyzed the patterns of transition from/to first use of inhalants to/from the first use of alcohol, tobacco, cannabis, cocaine, hallucinogens, ecstasy, amphetamines, prescription opioids, and tranquilizers. Cox proportional hazards models were used to analyze data. Drugs that were not specified as the pair of drugs tested in each model were included as time-varying covariates in all models. In this sample, first use of inhalants was preceded only by the first use of alcohol and tobacco. However, first use of inhalants preceded first use of cannabis, amphetamines, cocaine, and tranquilizers. First use of inhalants preceded the first use of prescription opioids, and vice versa. This study highlights the need to intervene early with youths who are at risk of or just beginning to use inhalants, because this class of drugs seems to be the first illegal drug in Brazil to be experimented by respondents in our sample. There is also a call for attention to individuals who have already first used inhalants because of their higher chance to experiment with other drugs such as cannabis, cocaine, and prescription drugs. All these findings show an in-transition culture of drug use, which should be tracked through time, because some classical models (i.e., gateway model) might be outdated and might also not fit within different settings.

Estimating the heterogeneous relationship between peer drinking and youth alcohol consumption in Chile using propensity score stratification

When estimating the association between peer and youth alcohol consumption, it is critical to account for possible differential levels of response to peer socialization processes across youth, in addition to variability in individual, family, and social factors. Failure to account for intrinsic differences in youth's response to peers may pose a threat of selection bias. To address this issue, we used a propensity score stratification method to examine whether the size of the association between peer and youth drinking is contingent upon differential predicted probabilities of associating with alcohol-consuming friends. Analyzing a Chilean youth sample (N = 914) of substance use, we found that youths are susceptible to the detrimental role of peer drinkers, but the harmful relationship with one's own drinking behavior may be exacerbated among youth who already have a high probability of socializing with peers who drink. In other words, computing a single weighted-average estimate for peer drinking would have underestimated the detrimental role of peers, particularly among at-risk youths, and overestimated the role of drinking peers among youths who are less susceptible to peer socialization processes. Heterogeneous patterns in the association between peer and youth drinking may shed light on social policies that target at-risk youths.

The role of drug use sequencing pattern in further problematic use of alcohol, tobacco, cannabis, and other drugs

BACKGROUND

There has been considerable debate regarding what typically occurs after experimentation with drugs throughout the life of young people who used various drugs.

AIMS

To evaluate the clinical importance of the most common sequence for the first use of a drug by two models (the "gateway model" and the "alternative model", which is the most popular sequence for Brazilian university students according to a previous study) regarding the problematic use of alcohol, tobacco, cannabis and other illegal drugs, assessed by ASSIST.

METHOD

People who had already experimented with three or more drugs across different stages of the two models were selected from a representative sample of university students from 27 Brazilian capitals (n = 12 711).

FINDINGS

There were no differences regarding the problematic use of the most consumed drugs in Brazil (alcohol, tobacco and cannabis) between the models. Multiple drug seekers and violators had more problematic use of illegal drugs other than cannabis than individuals in the model sequence. However, in the case of violators, this was only evident in the alternative model.

CONCLUSIONS

Multiple drug seekers and violators deserve special attention due to their increased risk of problematic use of other illegal drugs.

Use transition between illegal drugs among Brazilian university students

PURPOSE

The aim of the present study was to test whether the first use of an illicit drug increases the chance of first use of other illicit drugs.

METHOD

The transitions from the first use of a drug to the first use of another drug were analyzed. Comparisons were made between first drug users and non-users. Survival analysis methods were used to compare the cumulative probability of second drug use after adjusting for socio-demographic covariates and the intermediate use of alcohol and/or tobacco. A total of 12,721 Brazilian university students participated in this study.

RESULTS

Inhalants and marijuana were used prior to the use of several other drugs, whereas the opposite pattern was not found. Ecstasy was used before other drugs in several instances. Other well-examined drugs, such as amphetamines, cocaine and hallucinogens, were used both before and after other illicit drugs without any marked predominance for either of the two roles.

CONCLUSIONS

This study supports the role of the use of marijuana and inhalants almost exclusively before the use of other illicit drugs, whereas the use of ecstasy has an opposite role. These roles could be linked to the prevalence of lifetime use and whether individuals were at an earlier or later age during experimentation.

The association of recreational space with youth smoking in low-socioeconomic status neighborhoods in Santiago, Chile

OBJECTIVES

This study examines the relationship of neighborhood recreational space with youth smoking in mid- to low-income areas in the capital of Chile, Santiago.

METHODS

A unique data set of adolescents (n = 779, mean age = 14, 51 % male) provided home addresses of study participants which were geocoded and mapped. Satellite maps of neighborhoods were used to identify open spaces for recreational use (e.g., soccer fields and plazas). Thiessen polygons were generated to associate study participants with the nearest available open space using ArcGIS. Regression models, with smoking as a dependent variable, were estimated in which age, sex, family socioeconomic status, peer substance usage, neighborhood crime, and accessibility of open space were covariates.

RESULTS

The results show that residential proximity to recreational space was significantly and inversely associated with tobacco consumption among female, but not male, adolescents. Age and neighborhood crime were both positively associated with tobacco consumption among both male and female adolescents.

CONCLUSIONS

This study suggests that recreational spaces in proximity to residences may have a positive impact on reducing adolescents' inclination to consume tobacco. The relationship of the accessibility to such spaces with smoking appears to vary by adolescents' sex.

Perceived discrimination is a potential contributing factor to substance use and mental health problems among primary care patients in Chile

OBJECTIVES

Perceived discrimination is a prevalent problem that has been linked to negative health outcomes for victims. The goal of this research was to examine whether perceived discrimination within the past 6 months was related to 6-month prevalence of problem drinking, illicit drug use, major depressive disorder (MDD), and posttraumatic stress disorder (PTSD) in a sample of primary care patients in Chile.

METHODS

Structured diagnostic assessments were administered to assess for MDD and PTSD using the Composite International Diagnostic Interview. The Alcohol Use Disorders Identification Test assessed hazardous alcohol use. Additional measures captured illegal drug use and discrimination in the past 6 months. Measures were administered to 2839 participants between the ages of 15 to 98 in primary care centers in the Chilean cities of Concepcion and Talcahuano.

RESULTS

Controlling for demographic variables and previous trauma victimization, patients who reported discrimination in the past 6 months were significantly more likely to engage in hazardous alcohol use, illegal drug use, be diagnosed with MDD, and PTSD within this same time period than patients not reporting discrimination.

CONCLUSIONS

This study highlights the importance of considering discrimination as a potential contributing factor to substance use and mental health problems in a Latin American sample.

Do parent-child acculturation gaps affect early adolescent Latino alcohol use? A study of the probability and extent of use

The literature has been mixed regarding how parent–child relationships are affected by the acculturation process and how this process relates to alcohol use among Latino youth. The mixed results may be due to, at least, two factors: First, staggered migration in which one or both parents arrive to the new country and then send for the children may lead to faster acculturation in parents than in children for some families. Second, acculturation may have different effects depending on which aspects of alcohol use are being examined. This study addresses the first factor by testing for a curvilinear trend in the acculturation-alcohol use relationship and the second by modeling past year alcohol use as a zero inflated negative binomial distribution. Additionally, this study examined the unique and mediation effects of parent–child acculturation discrepancies (gap), mother involvement in children’s schooling, father involvement in children’s schooling, and effective parenting on youth alcohol use during the last 12 months, measured as the probability of using and the extent of use. Direct paths from parent–child acculturation discrepancy to alcohol use, and mediated paths through mother involvement, father involvement, and effective parenting were also tested. Only father involvement fully mediated the path from parent–child acculturation discrepancies to the probability of alcohol use. None of the variables examined mediated the path from parent–child acculturation discrepancies to the extent of alcohol use. Effective parenting was unrelated to acculturation discrepancies; however, it maintained a significant direct effect on the probability of youth alcohol use and the extent of use after controlling for mother and father involvement. Implications for prevention strategies are discussed.

Alcohol consumption among Chilean adolescents: Examining individual, peer, parenting and environmental factors

AIMS

This study examined whether adolescents from Santiago, Chile who had never drunk alcohol differed from those who had drunk alcohol but who had never experienced an alcohol-related problem, as well as from those who had drunk and who had experienced at least one alcohol-related problem on a number of variables from four domains - individual, peers, parenting, and environmental.

DESIGN

Cross-sectional.

SETTING

Community based sample.

PARTICIPANTS

909 adolescents from Santiago, Chile.

MEASUREMENTS

Data were analyzed with multinomial logistic regression to compare adolescents who had never drunk alcohol (non-drinkers) with i) those that had drunk but who had experienced no alcohol-related problems (non-problematic drinkers) and ii) those who had drunk alcohol and had experienced at least one alcohol-related problem (problematic drinkers). The analyses included individual, peer, parenting, and environmental factors while controlling for age, sex, and socioeconomic status.

FINDINGS

Compared to non-drinkers, both non-problematic and problematic drinkers were older, reported having more friends who drank alcohol, greater exposure to alcohol ads, lower levels of parental monitoring, and more risk-taking behaviors. In addition, problematic drinkers placed less importance on religious faith to make daily life decisions and had higher perceptions of neighborhood crime than non-drinkers.

CONCLUSIONS

Prevention programs aimed at decreasing problematic drinking could benefit from drawing upon adolescents' spiritual sources of strength, reinforcing parental tools to monitor their adolescents, and improving environmental and neighborhood conditions.

Drug resistance and substance use among male and female adolescents in alternative secondary schools in Guanajuato, Mexico

OBJECTIVE

Research is limited on the strategies that Mexican adolescents use to resist use of alcohol, cigarettes, and other drugs. Cultural norms and gender socialization patterns concerning the acceptability of use of various substances by women and men influence Mexican youths in their responses to offers of substances. This study explored the drug-resistance strategies used by youth in the central Mexican state of Guanajuato, how their use predicted patterns of substance use, and how these associations differed by gender.

METHOD

The analysis used cross-sectional survey data from 702 (60% male) students enrolled in eight alternative secondary education school sites in 2007. Participants reported the drug-resistance behaviors they used to deal with offers of alcohol, cigarettes, and marijuana. Past-12-month use of the four drug-resistance strategies employed most often by U.S. youth-refuse, explain, avoid, and leave (R.E.A.L.)-and any other strategies were measured. Composite measures of lifetime and recent use of alcohol, cigarettes, and marijuana were predicted in multivariate ordinary least squares regression analyses. Models were tested with and without controls for the frequency that respondents were offered substances and introduced gender interaction effects.

RESULTS

Controlling for substance use offers, more frequent use of a wide repertoire of R.E.A.L. strategies predicted less consumption of alcohol and cigarettes, and using non-R.E.A.L. strategies predicted less marijuana consumption. All of these relationships were either stronger for males than for females or significant for males only.

CONCLUSIONS

Gender differences exist in the impact of R.E.A.L. strategies on substance use among youth in Mexico. Despite a narrowing gender gap in substance use in Mexico, large exposure to and susceptibility of substance use remains. Developing effective prevention programs in Mexico based on teaching appropriate drug-resistance strategies and enhancing communication skills could aid in reducing substance use among Mexican adolescents.

The relevance of age at first alcohol and nicotine use for initiation of cannabis use and progression to cannabis use disorders

BACKGROUND

A younger age at onset of use of a specific substance is a well-documented risk-factor for a substance use disorder (SUD) related to that specific substance. However, the cross-substance relationship between a younger age at onset of alcohol use (AU) and nicotine use (NU) and the risk of cannabis use disorders (CUD) in adolescence and early adulthood remains unclear.

AIMS

To identify the sequence of and latency between initial AU/NU and initial cannabis use (CU). To investigate whether younger age at AU- and NU-onset is associated with any and earlier CU-onset and a higher risk of transition from first CU to CUD, taking into account externalizing disorders (ED) and parental substance use disorders as putative influential factors.

METHODS

Prospective-longitudinal community study with N=3021 subjects (baseline age 14-24) and up to four assessment waves over up to ten years with additional direct parental and family history information. Substance use and CUD were assessed with the DSM-IV/M-CIDI.

RESULTS

Most subjects with CU reported AU (99%) and NU (94%). Among users of both substances, 93% reported AU prior to CU (87% for NU). After adjustment for ED and parental substance use disorders younger age at AU-onset was associated with any CU. Younger age at NU-onset was associated with earlier CU initiation. Younger age at AU- and NU-onset was not associated with a higher risk of CUD.

CONCLUSIONS

The cross-substance relevance of younger age at first AU and NU for the risk of CUD is limited to early CU involvement.

Drug use opportunities as opportunities for drug use prevention: Bogotá, Colombia a case in point

BACKGROUND

As drugs become more ubiquitous and fewer resources are available for drug prevention and treatment, understanding the early stages of drug use involvement becomes increasingly important for prevention efforts. This study aims to explore the concept of drug use opportunity, and to disentangle, from a socio-ecological perspective, the factors associated with experiencing a drug use opportunity.

METHODS

Data from 2279 standardized questionnaires administered in 23 schools in Bogotá was analyzed. Schools were selected in a multistage probability cluster sample. Multilevel logistic regression modeling estimated the effects of multiple level factors on the likelihood of having experienced an opportunity to use illicit drugs or inhalants.

RESULTS

One-third of respondents (32.1%) reported having had an opportunity to use drugs. Even among those who perceived drugs to be readily available and/or expressed intentions to use drugs in the near future, most reported never having experienced an opportunity to use drugs. For most of the drugs assessed, peer drug use, cigarette smoking, alcohol drinking, problematic behavior, and degree of school safety were the strongest correlates of having had a drug use opportunity.

CONCLUSIONS

Despite living in an environment of high drug availability, most adolescents do not experience opportunities to use drugs. The likelihood of experiencing an opportunity is influenced by multiple interacting individual and macro-social factors, just as drug use is. Drug use opportunities were mainly promoted by friends, suggesting the need to consider their role within close social networks, alongside that of drug suppliers, in the design of intervention activities and drug policy development.

The Role of Peers and Parents in Predicting Alcohol Consumption among Chilean Youth

This study estimated marginal associations of parent- and peer-related measures to examine the different patterns of lifetime ever-use and frequency of alcohol consumption among adolescents in Santiago, Chile (N=918). Probit and negative binomial models were applied to predict the probability of ever-use and the average number of drinks consumed in the past 30 days. Results supported the profound role of peer-relationships in the development of youth drinking behavior. Particularly, peer pressure seemed more important in predicting alcohol ever-use than the frequency of drinking. Simultaneously, parents, especially fathers, played a crucial protective role. Policies aimed at preventing various drinking patterns may be more effective if they not only focus on the targeted adolescents, but also reach out to peers and parents.

The Association of Family and Peer Factors with Tobacco, Alcohol, and Marijuana Use Among Chilean adolescents in Neighborhood Context

Research on adolescent use of substances has long sought to understand the family factors that may be associated with use of different substances such as alcohol, tobacco, and marijuana. However, scant attention has been focused on these questions in Latin American contexts, despite growing concerns about substance use among Latin American youth. Using data from a sample of 866 Chilean youth, we examined the relationship of family and neighborhood factors with youth substance abuse. We found that in a Latin American context, access to substances is an important predictor of use, but that neighborhood effects differ for marijuana use as opposed to cigarettes or alcohol. Age of youth, family and peer relationships, and gender all play significant roles in substance use. The study findings provide additional evidence that the use of substances is complex, whereby individual, family, and community influences must be considered jointly to prevent or reduce substance use among adolescents.

Childhood predictors of first chance to use and use of cannabis by young adulthood

AIMS

To prospectively examine the linkage between childhood antecedents and progression to early cannabis involvement as manifest in first chance to try it and then first onset of cannabis use.

METHODS

Two consecutive cohorts of children entering first grade of a public school system of a large mid-Atlantic city in the mid 1980s (n=2311) were assessed (mean age 6.5 years) and then followed into young adulthood (15 years later, mean age 21) when first chance to try and first use were assessed for 75% (n=1698) of the original sample. Assessments obtained at school included standardized readiness scores (reading; math) and teacher ratings of behavioral problems. Regression and time to event models included covariates for sex, race, and family disadvantage.

RESULTS

Early classroom misconduct, better reading readiness, and better math readiness predicted either occurrence or timing of first chance to try cannabis, first use, or both. Higher levels of childhood concentration problems and lower social connectedness were not predictive.

CONCLUSIONS

Childhood school readiness and behavioral problems may influence the risk for cannabis smoking indirectly via an increased likelihood of first chance to use. Prevention efforts that seek to shield youths from having a chance to try cannabis might benefit from attention to early predictive behavioral and school readiness characteristics. When a youth's chance to try cannabis is discovered, there are new windows of opportunity for prevention and intervention.

Family and parenting characteristics associated with marijuana use by Chilean adolescents

OBJECTIVE: Family involvement and several characteristics of parenting have been suggested to be protective factors for adolescent substance use. Some parenting behaviors may have stronger relationships with adolescent behavior while others may have associations with undesirable behavior among youth. Although it is generally acknowledged that families play an important role in the lives of Chilean adolescents, scant research exists on how different family and parenting factors may be associated with marijuana use and related problems in this population which has one of the highest rates of drug use in Latin America. METHODS: Using logistic regression and negative binomial regression, we examined whether a large number of family and parenting variables were associated with the possibility of Chilean adolescents ever using marijuana, and with marijuana-related problems. Analyses controlled for a number of demographic and peer-related variables. RESULTS: Controlling for other parenting and family variables, adolescent reports of parental marijuana use showed a significant and positive association with adolescent marijuana use. The multivariate models also revealed that harsh parenting by fathers was the only family variable associated with the number of marijuana-related problems youth experienced. CONCLUSION: Of all the family and parenting variables studied, perceptions of parental use of marijuana and harsh parenting by fathers were predictors for marijuana use, and the experience of marijuana-related problems. Prevention interventions need to continue emphasizing the critical socializing role that parental behavior plays in their children's development and potential use of marijuana.

Prevalence and correlates of atypical patterns of drug use progression: findings from the South African Stress and Health Study

OBJECTIVE

Atypical sequences of drug use progression are thought to have important implications for the development of substance dependence. The extent to which this assumption holds for South African populations is unknown. This paper attempts to address this gap by examining the prevalence and correlates of atypical patterns of drug progression among South Africans.

METHOD

Data on substance use and other mental health disorders from a nationally representative sample of 4351 South Africans were analysed. Weighted cross tabulations were used to estimate prevalence and correlates of atypical patterns of drug use progression.

RESULTS

Overall, 12.2% of the sample reported atypical patterns of drug use progression. The most common violation was the use of extra-medical drugs prior to alcohol and tobacco. Gender was significantly associated with atypical patterns of drug use with the risk pattern varying by the type of drug. None of the anxiety or mood disorders were associated with atypical patterns of use. Atypical patterns of drug use were not associated with increased risk for a lifetime substance use disorder.

CONCLUSION

Atypical patterns of drug use initiation seem more prevalent in South Africa compared to other countries. The early use of extra-medical drugs is common, especially among young women. Drug availability and social environmental factors may influence patterns of drug use. The findings have important implications for prevention initiatives and future research.

Novel phenotype issues raised in cross-national epidemiological research on drug dependence

Stage-transition models based on the American Diagnostic and Statistical Manual (DSM) generally are applied in epidemiology and genetics research on drug dependence syndromes associated with cannabis, cocaine, and other internationally regulated drugs (IRDs). Difficulties with DSM stage-transition models have surfaced during cross-national research intended to provide a truly global perspective, such as the work of the World Mental Health Surveys Consortium. Alternative simpler dependence-related phenotypes are possible, including population-level count process models for steps early and before coalescence of clinical features into a coherent syndrome (e.g., zero-inflated Poisson [ZIP] regression). Selected findings are reviewed, based on ZIP modeling of alcohol, tobacco, and IRD count processes, with an illustration that may stimulate new research on genetic susceptibility traits. The annual National Surveys on Drug Use and Health (NSDUH) can be readily modified for this purpose, along the lines of a truly anonymous research approach that can help make NSDUH-type cross-national epidemiological surveys more useful in the context of subsequent genomewide association (GWAS) research and post-GWAS investigations with a truly global health perspective.