High Prevalence and Early Onsets: Legal and Illegal Substance Use in an Urban Cohort of Young Adults in Switzerland

INTRODUCTION

Debates about the legalization of illegal substances (e.g., cannabis) continue around the globe. A key consideration in these debates is the adequate protection of young people, which could be informed by current prevalence and age-of-onset patterns. For Switzerland, such information is limited, which is particularly true for women, despite advanced political efforts to legalize cannabis. The objective of the current study was to investigate substance use prevalence rates and ages of onset in a community-representative sample of female and male young adults in Switzerland.

METHODS

Data came from the Zurich Project on the Social Development from Childhood to Adulthood (z-proso). In 2018, participants (N = 1,180, 50.8% females) were ∼20 years old. Lifetime and past-year use of alcohol, tobacco, cannabinoids, stimulants, hallucinogens, opioids, and benzodiazepines were assessed with an extensive substance use questionnaire. Additionally, ages of onsets of the respective substances were estimated by averaging participants' self-reported ages of onsets from ages 13 to 20 (max. 4 assessments).

RESULTS

57% of 20-year-olds had used cannabinoids, 16% stimulants, 15% opioids (mostly codeine), and 8% hallucinogens in the past year. Males had higher prevalence than females for most drugs; nevertheless, females' prevalence rates were notably high. Legal substance use was typically initiated 1.3-2.7 years before legal selling age. Thus, almost half of the sample had consumed alcohol and tobacco by age 14. More than 40% of the total sample had smoked cannabis by age 16. Males initiated use of legal substances and cannabis earlier than females.

DISCUSSION

Our recent community-representative data suggested unexpectedly high levels and early onsets of substance use compared to a previous Swiss surveys and also the European average. Drug policy debates should consider urban substance use patterns when considering legalization efforts.

Has Cannabis Use Among Youth Increased After Changes in Its Legal Status? A Commentary on Use of Monitoring the Future for Analyses of Changes in State Cannabis Laws

As US states move toward various forms of adult access to cannabis, there has been a great interest in measuring the impact of such changes on adolescent cannabis use. Two recent prominent analyses have used Monitoring the Future (MTF), a nationally representative survey of students, to examine the effects. We compared MTF data for California and for Washington State with other survey data on use by adolescents in those states. In both studies, findings based on MTF were different from those using other larger, state-representative surveys. The discrepancy reflects the high within-state variation in prevalence rates and the small number of schools in MTF state samples. Using the Washington Health Youth Survey, we estimate that after recreational cannabis legalization past 30-day cannabis use prevalence in grade 8 decreased by 22.0%, in grade 10 prevalence decreased by 12.7%, and no effect in grade 12. These trends are consistent with those in states without recreational cannabis laws, suggesting that legalization did not impact adolescent use prevalence. Long-term trends in MTF are consistent with other data, but year-to-year volatility in state-level series undermines the survey's suitability for evaluation of state cannabis policy changes. Survey-based analyses at the state level need to be cross-validated with findings from other data sources. When findings are disparate and methodological rigor is equivalent, analyses of data sources specifically designed to describe state-level phenomena are more credible.

Trends in Adolescent Heroin and Injection Drug Use in Nine Urban Centers in the U.S., 1999-2017

PURPOSE

Although estimates of heroin and injection drug use (IDU) among U.S. adolescents have remained low and stable, national data may mask local variation in use. Adolescent use may be higher in urban areas, many of which have historically high rates of heroin use and IDU. We investigate trends in heroin use and IDU among 9th-12th grade students in major urban centers in the U.S.

METHODS

We used local Youth Risk Behavior Survey data from all large, urban school districts (n = 9) with at least 5 years of weighted, publicly available data. We used time series mean estimation to estimate the prevalence of heroin use and IDU among high school students from 1999 to 2017 and used logistic regression to test for linear and quadratic trends.

RESULTS

We observed statistically significant linear increases in (1) lifetime heroin use in New York (β = .43, 1%-3.9%), Chicago (β = .15, 3.1%-4.6%), and Milwaukee (β = .35, 2.8%-7.4%); and (2) lifetime IDU in New York (β = .34, .8%-2.7%), Orange County (β = .17, 2.2%-3.5%), and Miami-Dade County (β = .16, 2.7%-3.9%). Only San Bernardino experienced significant decreases in heroin use (β = -.34, 4.6%-1.6%) and IDU (β = -.20, 2.5%-1.9%) over the time period.

CONCLUSIONS

In contrast to national trends, the prevalence of heroin use is increasing among adolescents in certain urban centers in the U.S. Our results illustrate that national averages mask local variation in adolescent heroin use. Further research with locally representative samples is needed to inform public health policy and practice, especially in cities where heroin problems have been historically endemic and continue to rise.

Loose regulation of medical marijuana programs associated with higher rates of adult marijuana use but not cannabis use disorder

BACKGROUND AND AIMS

Most US states have passed medical marijuana laws (MMLs), with great variation in program regulation impacting enrollment rates. We aimed to compare changes in rates of marijuana use, heavy use and cannabis use disorder across age groups while accounting for whether states enacted medicalized (highly regulated) or non-medical mml programs.

DESIGN

Difference-in-differences estimates with time-varying state-level MML coded by program type (medicalized versus non-medical). Multi-level linear regression models adjusted for state-level random effects and covariates as well as historical trends in use.

SETTING

Nation-wide cross-sectional survey data from the US National Survey of Drug Use and Health (NSDUH) restricted use data portal aggregated at the state level.

PARTICIPANTS

Participants comprised 2004-13 NSDUH respondents (n ~ 67 500/year); age groups 12-17, 18-25 and 26+ years. States had implemented eight medicalized and 15 non-medical MML programs.

MEASUREMENTS

Primary outcome measures included (1) active (past-month) marijuana use; (2) heavy use (> 300 days/year); and (3) cannabis use disorder diagnosis, based on DSM-IV criteria. Covariates included program type, age group and state-level characteristics throughout the study period.

FINDINGS

Adults 26+ years of age living in states with non-medical MML programs increased past-month marijuana use 1.46% (from 4.13 to 6.59%, P = 0.01), skewing towards greater heavy marijuana by 2.36% (from 14.94 to 17.30, P = 0.09) after MMLs were enacted. However, no associated increase in the prevalence of cannabis use disorder was found during the study period. Our findings do not show increases in prevalence of marijuana use among adults in states with medicalized MML programs. Additionally, there were no increases in adolescent or young adult marijuana outcomes following MML passage, irrespective of program type.

CONCLUSIONS

Non-medical marijuana laws enacted in US states are associated with increased marijuana use, but only among adults aged 26+ years. Researchers and policymakers should consider program regulation and subgroup characteristics (i.e. demographics) when assessing for population level outcomes. Researchers and policymakers should consider program regulation and subgroup characteristics (i.e. demographics) when assessing for population level outcomes.

The power of the proposition: frequency of marijuana offers, parental knowledge, and adolescent marijuana use

BACKGROUND

The frequency with which adolescents are offered marijuana has been investigated as a predictor of marijuana use. The current study was designed to test whether the number of marijuana offers received provides an indirect path between parental knowledge and adolescents' marijuana use.

METHODS

Data from the nationally representative National Survey of Parents and Youth were examined. Analysis 1 tested the association between frequency of being offered marijuana and adolescents' (N=4264) marijuana usage in the subsequent year. Analysis 2, spanning a three-year time frame, tested whether the frequency of marijuana offers at the second year of the panel study bridged the relationship between parental knowledge in Year 1 and marijuana use in Year 3.

RESULTS

Analysis 1 indicated that the frequency with which adolescents were offered marijuana predicted usage one year later, after controlling for previous usage and nine other common predictors of marijuana use. Analysis 2 revealed an indirect relationship between parental knowledge and use through the number of marijuana offers the adolescent received.

CONCLUSION

There was a strong link between the number of offers received and adolescents' future marijuana use. Higher parental knowledge predicted reductions in offer frequency, which was associated with lower levels of marijuana use. Reducing the number of marijuana offers an adolescent receives could serve as a useful focus for intervention programs targeting parents.

The role of general parenting and cannabis-specific parenting practices in adolescent cannabis and other illicit drug use

AIMS

To investigate general and cannabis-specific parenting practices in relation to adolescent cannabis and other illicit drug use.

METHODS

Data were derived from the Dutch National School Survey on Substance Use among students (N=3209; aged 12-16 years) and one of their parents in 2011.

RESULTS

Logistic regression analyses revealed that 1) parental cannabis use was significantly related to more adolescent lifetime and recent cannabis use, and 2) restrictive cannabis-specific parental rules were associated with less adolescent recent cannabis and lifetime use of other illicit drugs, even when controlled for sociodemographic factors, general parenting, adolescent tobacco use, and tobacco-specific parenting. In addition, no significant interaction was observed between parental cannabis use and cannabis-specific rules in their relation to adolescent cannabis and other illicit drug use, indicating that cannabis rules are evenly associated with adolescent drug use for families with and without parental cannabis experience.

CONCLUSIONS

In addition to general parenting practices, restrictive cannabis-specific rules are related to lower adolescent cannabis and other illicit drug rates. Parents who ever used cannabis have children with a higher prevalence of cannabis use. However, their restrictive cannabis-specific rules are equally related to a lower chance of adolescent cannabis use.

Transforming prevention systems in the United States and the Netherlands using Communities That Care Promising prevention in the eyes of Josine Junger-Tas

Josine Junger-Tas introduced the Communities That Care (CTC) prevention system to the Netherlands as a promising approach to address the growing youth violence and delinquency. Using data from a randomized trial of CTC in the United States and a quasi-experimental study of CTC in the Netherlands, this article describes the results of a comparison of the implementation of CTC in 12 U.S. communities and 5 Dutch neighborhoods. CTC communities in both countries achieved higher stages of a science-based approach to prevention than control communities, but full implementation of CTC in the Netherlands was hampered by the very small list of prevention programs tested and found effective in the Dutch context.

A Cross-national Comparison of Risk and Protective Factors for Adolescent Drug Use and Delinquency in the United States and the Netherlands

The present study compared associations between risk and protective factors and adolescent drug use and delinquency in the Netherlands and the United States. Data were collected from students between the ages of 12 and 17 using the same school-administered survey instrument in both countries. Levels of exposure to risk and protective factors were generally similar in both countries. The same risk and protective factors shown to be associated with U.S. adolescents' drug use and delinquency were related significantly to Dutch youth's drug use and delinquency. One important exception was that Dutch students perceived their parents' attitudes to be more favorable toward alcohol use; these attitudes also were more predictive of adolescents' regular drinking in the Netherlands compared to the United States. The findings indicate that the risk and protective factors measured in this study can be important targets for prevention of health-compromising behaviors among young people in the Netherlands and the United States.