Cross-national comparisons of sex differences in opportunities to use alcohol or drugs, and the transitions to use

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.

Impacts of recreational cannabis legalization on use and harms: A narrative review of sex/gender differences

Legalization of cannabis use for non-medical (recreational) purposes is changing the global cannabis landscape. As attitudes toward cannabis use become more positive and prevalence of use increases in complex ways, concerns emerge about the potential for increased cannabis-attributable harms. Understanding the who, why, and when of this likely increase in cannabis-attributable harms is thus an important public health priority. Both sex and gender contribute to variability in the use, effects, and harms of cannabis and thus sex/gender considerations are important when evaluating the impacts of cannabis legalization. The goal of this narrative review is to broadly discuss sex/gender differences in attitudes toward and prevalence of cannabis use, whether there are sex/gender differences in the impacts of cannabis legalization, and why these sex/gender differences might exist. One of our strongest conclusions is that men have always been more likely to use cannabis than women, yet the sex/gender gap in prevalence of cannabis use has narrowed over time, and this might be partly due to cannabis legalization. The existing evidence suggests that there have also been sex/gender differences in the impacts of legalization on cannabis-attributable harms such as cannabis-involved motor vehicle collisions and hospitalizations, though these results are more variable. The body of literature reviewed has focused almost exclusively on samples of cisgender research participants, and thus future research should encourage inclusion of transgender and gender-diverse participants. More consideration of sex- and gender-based analysis in research evaluating long-term impacts of cannabis legalization is a clear research priority.

The transition to parenthood, opportunity to drink, drinking, and alcohol use disorder

BACKGROUND

This study used life histories from a setting of near universal marriage and childbearing (Nepal) to identify associations between both marital transitions and the transition into parenthood and alcohol use and disorder (AUD).

METHODS

A retrospective, cross-sectional survey using life history calendars documented lifetime marital and childbearing histories of 4876 men and 5742 women aged 15-59 in 2016-18. The clinically validated, Nepal-specific Composite International Diagnostic Interview assessed first alcohol use opportunity, use, and disorder.

RESULTS

Being never married increased the odds of having the opportunity to drink for men (OR=1.30, 95% CI=1.14 - 1.48, p < 0.001) and women (OR=1.24, 95% CI=1.08 - 1.43, p = 0.003) compared to being married. While men were never married, widowed, or divorced they were at a greater risk of developing AUD. The transition to parenthood significantly increased the odds of AUD onset for men (OR=1.71, 95% CI=1.12 - 2.61, p = 0.013), independent of marital transitions. For women in this setting, becoming divorced increased the odds of having their first drink (OR=1.77, 95% CI=1.14 - 2.75, p = 0.011). Giving birth to a first child also increased the odds of first opportunity to drink for women (OR=1.30, 95% CI=1.07 - 1.57, p = 0.008).

CONCLUSIONS

We found associations between marital transitions and AUD that are consistent with findings worldwide. In this setting of near universal childbearing, the transition into fatherhood increased the odds of postpartum AUD among men.

Structural gender inequality and gender differences in adolescent substance use: A multilevel study from 45 countries

-Societal gender inequality relates to gender differences in adolescent substance use.-The gender gap in adolescent substance use is larger in countries with higher levels of gender inequality.-Girls in these countries were less likely to get drunk, use alcohol or smoke cigarettes than boys.

Predictors of transitions across stages of alcohol use and disorders in an adult population with heterogeneous ethnic restrictions regarding drinking

AIMS

To disaggregate associations with alcohol use disorder relative to those with early alcohol use stages in an adult population. We estimated prevalence rates and socio-demographic correlates for the opportunity to drink and transitions into life-time alcohol use, regular use and alcohol use disorder.

DESIGN

A retrospective, cross-sectional population survey within a family panel study.

SETTING

Chitwan in Nepal, an ethnically diverse setting with heterogeneous ethnic restrictions regarding alcohol.

PARTICIPANTS

A total of 10 714 individuals aged 15-59 years (response rate = 93%).

MEASUREMENTS

The Nepal-specific Composite International Diagnostic Interview assessed life-time alcohol use opportunity, any use, regular use, disorder and socio-demographic characteristics.

FINDINGS

Seventy per cent [95% confidence interval (CI) = 69.08-70.82%] of the population had the opportunity to drink, 38.06% (95% CI = 37.14-38.99%) had life-time alcohol use, 32.37% (95% CI = 31.48-33.27%) had regular alcohol use and 6.04% (95% CI = 5.60-6.50%) developed an alcohol use disorder. Compared with high-caste Hindus, all other ethnicities had greater odds of early stage transitions [odds ratios (OR) ranged from 1.31, 95% CI = 1.16-1.47 to 1.98, 95% CI = 1.81-2.18)], but not of development of disorder. Male sex was associated with greater odds of all transitions, from opportunity (OR = 5.71, 95% CI = 5.41-6.03) to development of disorder (OR = 1.95, 95% CI = 1.35-2.81). The youngest cohort had higher odds of all transitions, from opportunity (OR = 4.86, 95% CI = 4.47-5.29) to development of disorder (OR = 9.34, 95% CI = 6.88-12.70). Higher education was associated with lower odds of all transitions except opportunity [from use (OR = 0.77, 95% CI = 0.71-0.83) to the development of disorder (OR = 0.73, 95% CI = 0.59-0.89)].

CONCLUSIONS

The prevalence of life-time alcohol use among adults in Nepal appears to be low, but the overall prevalence of disorder is similar to other countries. Socio-demographic correlates of early alcohol use transitions differ from those associated with later transitions; while sex and age cohort were associated with all transitions, ethnicity was associated with early transitions (opportunity, life-time use, regular use), but not later transitions (use and regular use to disorder).

Female-male differences in prescription pain reliever dependence levels: Evidence on newly incident adolescent and young adult users in the United States, 2002-2014

BACKGROUND

A comprehensive epidemiology of dependence on prescription opioid pain relievers requires evidence about age-specific female-male differences, possibly manifest during adolescent and early adult years. In this study, we identified newly incident extra-medical users of prescription pain relievers (EMPPR), all observed with onsets before the 22nd birthday. We then quantified female-male differences in clinical features or manifestations of opioid dependence (OD), devised a measurement-equivalent OD dimension, and estimated age-specific female-male differences in OD levels.

METHOD

The population under study included 12-to-21-year-old non-institutionalized civilian community residents of United States sampled for recent nation-scale surveys. Confidential computer-assisted self-interviews identified newly incident EMPPR users (n = 10,188). Analysis-weighted estimation procedures yielded cumulative incidence proportions for each OD feature, evaluated measurement non-equivalence across subgroups, and estimated female-male differences age-by-age.

RESULTS

(1) Tolerance and salience ('spending a lot of time') are most common OD features. (2) Measurement non-equivalence (bias) was found across sex- and onset-age groups. (3) With biasing features removed, we can see elevated OD levels for female new initiates, age-by-age. Subsidiary analyses suggested possibly accelerated progression toward higher OD levels when extra-medical PPR use starts before age 18.

CONCLUSIONS

Dimensional approaches to OD and other drug use disorders have gained popularity but can be fragile when differential measurement biases are left uncontrolled. This study's bias-corrected dimensional view of female-male differences shows elevated OD levels among newly incident female EMPPR users relative to new male initiates. Future studies can check for accelerated progression to higher OD levels when EM use starts before age 18 years.

Association of Cohort and Individual Substance Use With Risk of Transitioning to Drug Use, Drug Use Disorder, and Remission From Disorder: Findings From the World Mental Health Surveys

IMPORTANCE

Limited empirical research has examined the extent to which cohort-level prevalence of substance use is associated with the onset of drug use and transitioning into greater involvement with drug use.

OBJECTIVE

To use cross-national data to examine time-space variation in cohort-level drug use to assess its associations with onset and transitions across stages of drug use, abuse, dependence, and remission.

DESIGN, SETTING, AND PARTICIPANTS

The World Health Organization World Mental Health Surveys carried out cross-sectional general population surveys in 25 countries using a consistent research protocol and assessment instrument. Adults from representative household samples were interviewed face-to-face in the community in relation to drug use disorders. The surveys were conducted between 2001 and 2015. Data analysis was performed from July 2017 to July 2018.

MAIN OUTCOMES AND MEASURES

Data on timing of onset of lifetime drug use, DSM-IV drug use disorders, and remission from these disorders was assessed using the Composite International Diagnostic Interview. Associations of cohort-level alcohol prevalence and drug use prevalence were examined as factors associated with these transitions.

RESULTS

Among the 90 027 respondents (48.1% [SE, 0.2%] men; mean [SE] age, 42.1 [0.1] years), 1 in 4 (24.8% [SE, 0.2%]) reported either illicit drug use or extramedical use of prescription drugs at some point in their lifetime, but with substantial time-space variation in this prevalence. Among users, 9.1% (SE, 0.2%) met lifetime criteria for abuse, and 5.0% (SE, 0.2%) met criteria for dependence. Individuals who used 2 or more drugs had an increased risk of both abuse (odds ratio, 5.17 [95% CI, 4.66-5.73]; P < .001) and dependence (odds ratio, 5.99 [95% CI, 5.02-7.16]; P < .001) and reduced probability of remission from abuse (odds ratio, 0.86 [95% CI, 0.76-0.98]; P = .02). Birth cohort prevalence of drug use was also significantly associated with both initiation and illicit drug use transitions; for example, after controlling for individuals' experience of substance use and demographics, for each additional 10% of an individual's cohort using alcohol, a person's odds of initiating drug use increased by 28% (odds ratio, 1.28 [95% CI, 1.26-1.31]). Each 10% increase in a cohort's use of drug increased individual risk by 12% (1.12 [95% CI, 1.11-1.14]).

CONCLUSIONS AND RELEVANCE

Birth cohort substance use is associated with drug use involvement beyond the outcomes of individual histories of alcohol and other drug use. This has important implications for understanding pathways into and out of problematic drug use.

Transitions Through Stages of Alcohol Use, Use Disorder and Remission: Findings from Te Rau Hinengaro, The New Zealand Mental Health Survey

Aims

To understand transitions from alcohol use to disorder, we examine timing of transitions between stages of alcohol use and associations between transitions and socio-demographic factors.

Short summary

Using nationally representative data, we found that the majority of alcohol use disorders develop by age 25. Increased alcohol use within a participant's cohort was associated with subsequent transition across all stages of alcohol use and disorder. Fifty percent of dependence cases had not remitted after 9 years.

Methods

A nationally representative sample with a 73% response rate included 12,992 participants aged 16 and older. The Composite International Diagnostic Interview (CIDI 3.0) was used to assess age at initial alcohol consumption, commencement of regular consumption, symptoms of alcohol abuse and dependence, and year-long remission. Alcohol consumption in an age- and gender-matched cohort, education, gender and age at commencement of use were investigated as covariates.

Results

Among all respondents, 94.6% used alcohol, 85.1% used alcohol regularly, 11.4 and 4.6% had developed alcohol abuse and dependence disorders, respectively. Of those with an abuse or dependence disorder, 79.9 and 67.2% had remitted, respectively. Increased alcohol use within a participant's cohort was associated with subsequent transition across all stages. The majority of disorders had developed by age 25. Considerable time was spent with disorder; 50% of dependence cases had not remitted after 9 years. Men were at greater risk of disorder and less likely to remit.

Conclusions

Interventions should target young people and cohort-specific consumption with resources also allocated to long-term treatment provision for alcohol dependency.

Studying Sex Differences in Animal Models of Addiction: An Emphasis on Alcohol-Related Behaviors

Animal models are essential for understanding the biological factors that contribute to drug and alcohol addiction and discovering new pharmacotherapies to treat these disorders. Alcohol (ethanol) is the most commonly abused drug in the world, and as the prevalence of alcohol use disorder (AUD) increases, so does the need for effective pharmacotherapies. In particular, treatments with high efficacy in the growing number of female AUD sufferers are needed. Female animals remain underrepresented in biomedical research and sex differences in the brain's response to alcohol are poorly understood. To help bridge the gender gap in addiction research, this Review discusses strategies that researchers can use to examine sex differences in the context of several common animal models of AUD. Self-administration, two-bottle choice, drinking in the dark, and conditioned place preference are discussed, with a focus on the role of estrogen as a mediator of sex differences in alcohol-related behaviors.

The impact of cohort substance use upon likelihood of transitioning through stages of alcohol and cannabis use and use disorder: Findings from the Australian National Survey on Mental Health and Wellbeing

INTRODUCTION AND AIMS

We used population-level Australian data to estimate prevalence, age of onset and speed of transitions across stages of alcohol and cannabis use, abuse and dependence, and remission from disorder, and consider the potential impacts that an individual's age cohort's level of substance use predicted transitions into and out of substance use.

DESIGN AND METHODS

Data on use, DSM-IV use disorders, and remission from these disorders were collected from participants (n = 8463) in the 2007 Australian National Survey of Mental Health and Wellbeing using the Composite International Diagnostic Interview.

RESULTS

Lifetime prevalence (95% confidence interval) of alcohol use, regular use, abuse and dependence were 94.1% (93.3-94.8%), 64.5% (62.9-66.2%), 18.7% (17.4-19.9%) and 4.0% (3.4-4.6%). Lifetime prevalence of cannabis use, abuse and dependence were 19.8% (18.6-20.9%), 4.4% (3.8-5.0%) and 1.9% (1.5-2.4%). Among those with the disorder, rates of remission from cannabis abuse, alcohol abuse, cannabis dependence and alcohol dependence were 90.5% (87.4-93.6%), 86.2% (83.8-88.7%), 79.6% (71.1-88.1%) and 53.8% (46.6-61.0%). Increases in the estimated proportion of people in the respondent's age cohort who used alcohol/cannabis as of a given age were significantly associated with most transitions from use through to remission beginning at the same age.

DISCUSSION AND CONCLUSIONS

Clear associations were documented between cohort-level prevalence of substance use and personal risk of subsequent transitions of individuals in the cohort from use to greater substance involvement. This relationship remained significant over and above associations involving the individual's age of initiation. These findings have important implications for our understanding of the causal pathways into and out of problematic substance use.

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.

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.

Individual and contextual factors associated with tobacco, alcohol, and cannabis use among Chilean adolescents: A multilevel study

We studied the association between individual and contextual variables and the use of tobacco, alcohol, or cannabis in the last 30 days preceding the study, considering the hierarchical nature of students nested in schools. We used the 7th Chilean National School Survey of Substance Use (2007) covering 45,273 students (aged 12-21 years old) along with information from 1465 schools provided by the Chilean Ministry of Education. Multilevel univariable and multivariable logistic regression models were performed. We found a significant intra-class correlation within schools for all substances in the study. Common (e.g., availability of pocket money, more time spent with friends, poor parental monitoring, poor school bonding, bullying others, and lower risk perception of substance use) and unique predictors (e.g., school achievement on national tests) were identified. These findings may help in planning and conducting preventive interventions to reduce substance use.

Cannabis Epidemiology: A Selective Review

BACKGROUND

Globally, the most widely used set of compounds among the internationally regulated drugs is cannabis.

OBJECTIVE

To review evidence from epidemiological research on cannabis, organized in relation to this field's five main rubrics: quantity, location, causes, mechanisms, and prevention/ control.

METHOD

The review covers a selection of evidence from standardized population surveys, official statistics, and governmental reports, as well as published articles and books identified via MEDLINE, Web of Science, and Google Scholar as of July 2016.

RESULTS

In relation to quantity, an estimated 3% to 5% of the world population is thought to have tried a cannabis product, with at least one fairly recent use, mainly extra-medical and outside boundaries of prescribed use. Among cannabis users in the United States, roughly one in 7-8 has engaged in medical marijuana use. In relation to location, prevalence proportions reveal important variations across countries and between subgroups within countries. Regarding causes and mechanisms of starting to use cannabis, there is no compelling integrative and replicable conceptual model or theoretical formulation. Most studies of mechanisms have focused upon a 'gateway sequence' and person-to-person diffusion, with some recent work on disability-adjusted life years. A brief review of cannabis use consequences, as well as prevention and control strategies is also provided.

CONCLUSION

At present, we know much about the frequency and occurrence of cannabis use, with too little replicable definitive evidence with respect to the other main rubrics. Given a changing regulatory environment for cannabis products, new institutions such as an independent International Cannabis Products Safety Commission may be required to produce evidence required to weigh benefits versus costs. It is not clear that governmentsponsored research will be sufficient to meet consumer demand for balanced points of view and truly definitive evidence.

A new era for drinking? Epidemiological evidence on adolescent male-female differences in drinking incidence in the United States and Europe

PURPOSE

We seek answers to three questions about adolescent risk of starting to drink alcoholic beverages: (1) in new United States (US) data, can we reproduce a recently discovered female excess risk? (2) has a female excess risk emerged in European countries? and (3) might the size of country-level female-male differences (FMD) be influenced by macro-level gender equality and development processes?

METHODS

Estimates are from US and European surveys of adolescents, 2010-2014. For US estimates, newly incident drinking refers to consuming the first full drink during the 12-month interval just prior to assessment. For all countries, lifetime cumulative incidence of drinking refers to any drinking before assessment of the sampled 15-16 years.

RESULTS

Cumulative meta-analysis summary estimates from the US show a highly reproducible female excess in newly incident drinking among 12-17 years (final estimated female-male difference in risk, FMD = 2.1%; 95% confidence interval = 1.5%, 2.7%). Several European countries show female excess risk, estimated as lifetime cumulative incidence of drinking onsets before age 17 years. At the country level, the observed magnitude of FMD in risk is positively associated with the Gender Development Index (especially facets related to education and life expectancy of females relative to males), and with residence in a higher income European country.

CONCLUSIONS

New FMD estimates support reproducibility of a female excess risk in the US. In Europe, evidence of a female excess is modest. Educational attainment, life expectancies, and income merit attention in future FMD research on suspected macro-level processes that influence drinking onsets.

Taking the First Full Drink: Epidemiological Evidence on Male-Female Differences in the United States

BACKGROUND

This research extends prior epidemiological estimates for the United States and re-examines a previously described male excess in alcohol drinking. Its aim was to estimate fine-grained age-specific incidence of becoming a drinker among 12- to 24-year-old U.S. males and females, and to compare incidence estimates with prevalence proportions.

METHODS

The study population is 12- to 24-year-old noninstitutionalized U.S. civilian residents. Estimates are from 12 successive U.S. National Surveys on Drug Use and Health (NSDUH), with nationally representative samples drawn each year from 2002 to 2013 and assessed via computer-assisted self-interviews (n ~ 390,000). Analysis-weighted incidence and prevalence estimates are generated using the NSDUH Restricted Data Analysis System for 6 year-pairs. Meta-analysis-derived summary estimates are provided, treating each year-pair as a replication.

RESULTS

In this 21st century evidence, there no longer is male excess of incidence with respect to underage drinking. Indeed, in mid-adolescence, there is a clear female excess for the risk of becoming an underage drinker. Meta-analytic summaries disclosed no other male-female differences in incidence. Nevertheless, a male excess in the prevalence of recently active drinking can be seen after the age of 19 years.

CONCLUSIONS

This new evidence from the United States shows that the so-called "gender gap" in risk of becoming a drinker has narrowed to the point of there being no gap at all. Indeed, in mid-adolescence, risk of starting to drink is greater for females than for males.

Prospective relationship of depressive symptoms, drinking, and tobacco smoking among middle-aged and elderly community-dwelling adults: Results from the China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

Previous studies in Western countries have consistently documented positive associations of smoking and heavy drinking with depressive symptoms but a prospective analysis of these relationships among middle-aged and elderly community members in China have not previously been reported.

METHODS

Using data from the China Health and Retirement Longitudinal Study, a two-wave nationally representative survey conducted in 15,628 adults 45 years of age and older, we estimated the prospective association between depressive symptoms and an array of smoking and drinking behaviors. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D) short form.

RESULTS

Inverse associations were the dominant pattern of association. For the population as a whole, individuals with baseline depressive symptoms were less likely to start drinking (OR=0.7, 95% CI=0.5, 0.9) or smoking (OR=0.6, 95% CI=0.4, 0.8). Similarly, baseline drinkers and smokers were less likely to develop depressive symptoms (ORdrinkers=0.6, 95% CI=0.5, 0.7; ORsmokers=0.7, 95% CJ=0.6, 0.9). No evidence was found for an increased incidence or persistence of depressive symptoms among high-frequency drinkers or heavy smokers or vice versa. Males who had never smoked prior to the onset of depressive symptoms tended to have more rapid onset of tobacco dependence compared to those without such symptoms. Males and females had different association patterns.

LIMITATIONS

The study is observational in nature and provides limited evidence for causality.

DISCUSSION

The results are inconsistent with previous findings in Western countries, throwing into question the presumed universality of the association between alcohol drinking or tobacco use and depression among middle-aged and elderly adults.

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.

The increasing global health priority of substance use in young people

Substance use in young people (aged 10-24 years) might disrupt key periods of transition that occur as the adolescent brain undergoes cognitive and emotional development, and key psychosocial transitions are made. Adolescence is the peak time for initiation of substance use, with tobacco and alcohol usually preceding the use of illicit drugs. Substantial variation is noted between countries in the levels, types, and sequences of substance use in young people, indicating that a young person's use of substances depends on their social context, drug availability, and their personal characteristics. The Global Burden of Disease (GBD) 2013 study suggests that the burden attributable to substance use increases substantially in adolescence and young adulthood. In young men aged 20-24 years, alcohol and illicit substance use are responsible for 14% of total health burden. Alcohol causes most health burden in eastern Europe, and illicit drug burden is higher in the USA, Canada, Australia, New Zealand, and western Europe. Large gaps exist in epidemiological data about the extent of drug use worldwide and much of what we know about the natural history of substance use comes from cohort studies in high-income countries undertaken decades ago, which hinders effective global policy responses. In view of the global epidemiological transitions from diseases of poverty to non-communicable diseases, the burden of disease and health risks among adolescents and young adults is likely to change substantially, in ways that will no doubt see substance use playing an increasingly large part.

Sex and gender-related differences in alcohol use and its consequences: Contemporary knowledge and future research considerations

AIMS

To review the contemporary evidence reflecting male/female differences in alcohol use and its consequences along with the biological (sex-related) and psycho-socio-cultural (gender-related) factors associated with those differences.

METHODS

MEDLINE, PubMed, Web of Science, SCOPUS, PsycINFO, and CINAHL databases were searched for relevant publications, which were subsequently screened for the presence/absence of pre-specified criteria for high quality evidence.

RESULTS

Compared to men, more women are lifetime abstainers, drink less, and are less likely to engage in problem drinking, develop alcohol-related disorders or alcohol withdrawal symptoms. However, women drinking excessively develop more medical problems. Biological (sex-related) factors, including differences in alcohol pharmacokinetics as well as its effect on brain function and the levels of sex hormones may contribute to some of those differences. In addition, differences in alcohol effects on behavior may also be driven by psycho-socio-cultural (gender-related) factors. This is evident by variation in the magnitude of differences in alcohol use between countries, decreasing difference in the rates of alcohol consumption in recent generations and other findings. Evidence indicates that both sex and gender-related factors are interacting with alcohol use in complex manner, which differentially impacts the risk for development of the behavioral or medical problems and alcohol use disorders in men and women.

CONCLUSIONS

Discovery of the mechanisms underlying biological (sex-related) as well as psycho-socio-cultural (gender-related) differences in alcohol use and related disorders is needed for development of personalized recommendations for prevention and treatment of alcohol use disorders and related problems in men and women.

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.

Social contacts and Ecstasy offers: findings of a population-based study

Ecstasy (MDMA) use is relatively common among young adults in many developed countries. However, little is known about how young non-users are first introduced to Ecstasy, including the relative contribution of peer networks and individual risk factors. We assess the role of social contact with Ecstasy-using peers in regard to young adults' exposure to offers of Ecstasy, using data from the Natural History Study, a population-based study conducted in Australia. Population screening of young adults (19- to 23-year-olds) identified a sample of young Ecstasy users (N = 315) and a comparison group of Ecstasy-naïve participants (N = 199). Two outcomes are considered: being exposed to any Ecstasy offers and being exposed to > 3 offers. Extensive social contact with Ecstasy users was defined as knowing > 10 Ecstasy users. Of the Ecstasy-naïve young adults, > 40% had ever received Ecstasy offers. Extensive social contact with Ecstasy users independently predicted exposure to multiple (> 3) Ecstasy offers for Ecstasy-naïve young adults. These findings indicate that Ecstasy offers are widespread among users and non-users of Ecstasy. For non-users, exposure to Ecstasy offers occurs through social contact with drug-using peers independently of individual risk factors. The pervasiveness of Ecstasy offers suggests that universal education concerning Ecstasy use is required.

Young adults' recreational social environment as a predictor of ecstasy use initiation: findings of a population-based prospective study

AIMS

To examine prospectively the contribution of the recreational social environment to ecstasy initiation.

DESIGN

Population-based retrospective/prospective cohort study.

SETTING

Data from screening an Australian young adult population to obtain samples of users and non-users of ecstasy.

PARTICIPANTS

A sample of 204 ecstasy-naive participants aged 19-23 years was obtained, and a 6-month follow-up identified those who initiated ecstasy use.

MEASUREMENTS

We assessed a range of predictors of ecstasy initiation, including elements of participants' social environment, such as ecstasy-using social contacts and involvement in recreational settings.

FINDINGS

More than 40% of ecstasy-naive young adults reported ever receiving ecstasy offers. Ecstasy initiation after 6 months was predicted independently by having, at recruitment, many ecstasy-using social contacts [adjusted relative risk (ARR) 3.15, 95% confidence interval (CI): 1.57, 6.34], attending electronic/dance music events (ARR 6.97, 95% CI: 1.99, 24.37), receiving an ecstasy offer (ARR 4.02, 95% CI: 1.23, 13.10), early cannabis use (ARR 4.04, 95% CI: 1.78, 9.17) and psychological distress (ARR 5.34, 95% CI: 2.31, 12.33). Adjusted population-attributable fractions were highest for ecstasy-using social contacts (17.7%) and event attendance (15.1%).

CONCLUSIONS

In Australia, ecstasy initiation in early adulthood is associated predominantly with social environmental factors, including ecstasy-using social contacts and attendance at dance music events, and is associated less commonly with psychological distress and early cannabis use, respectively. A combination of universal and targeted education programmes may be appropriate for reducing rates of ecstasy initiation and associated harms.

Mexican immigration to the US and alcohol and drug use opportunities: does it make a difference in alcohol and/or drug use?

BACKGROUND

Mexican immigrants in the US do not have increased risk for alcohol use or alcohol use disorders when compared to Mexicans living in Mexico, but they are at higher risk for drug use and drug use disorders. It has been suggested that both availability and social norms are associated with these findings. We aimed to study whether the opportunity for alcohol and drug use, an indirect measure of substance availability, determines differences in first substance use among people of Mexican origin in both the US and Mexico, accounting for gender and age of immigration.

METHODS

Data come from nationally representative surveys in the United States (2001-2003) and Mexico (2001-2002) (combined n=3432). We used discrete time proportional hazards event history models to account for time-varying and time-invariant characteristics. The reference group was Mexicans living in Mexico without migration experience.

RESULTS

Female immigrants were at lower risk of having opportunities to use alcohol if they immigrated after the age of 13, but at higher risk if they immigrated prior to this age. Male immigrants showed no differences in opportunity to use alcohol or alcohol use after having the opportunity. Immigration was associated with having drugs opportunities for both sexes, with larger risk among females. Migration was also associated with greater risk of using drugs after having the opportunity, but only significantly for males.

CONCLUSIONS

The impacts of immigration on substance use opportunities are more important for drugs than alcohol. Public health messages and educational efforts should heed this distinction.

Steppingstone and gateway ideas: a discussion of origins, research challenges, and promising lines of research for the future

In this discussion of contributed papers for the special issue of DAD, the author draws attention to early American laws concerning cannabis and to statements made about the epidemiology of cannabis smoking and other drug use between 1858 and the contemporary scene, with coverage of opium, heroin, tobacco, alcohol, cocaine, kava, and other drugs. He discusses these steppingstone and gateway processes in relation to political environment and in relation to scientific challenges such as uncontrolled confounding. He provides a critique of between-individual research designs, including co-twin and co-sib designs of behavior genetics, as well as imaging research, where uncontrolled confounding often exists. He highlights the epidemiologic case-crossover design and prevention research experiments as potentially valuable approaches in new directions for research on the steppingstone and gateway processes.

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.