Trends In Cannabis Use Research Articles

Changes in cannabis use among young people

The aim of this review was to examine current trends in cannabis use and cannabis use disorder (CUD) among youth, and to investigate recent findings concerning the relationship between cannabis use and mental health concerns, with a focus on how use during adolescence may interact with related mental health disorders. Current data indicate that cannabis use among adolescents has shown both marginal increases and decreases, depending on global location; however, the profile of cannabinoids in cannabis may now be biased toward those that promote psychotogenic and memory-impairing effects. CUD has been found most prevalent among youth. After controlling for multiple confounders, longitudinal research suggests that cannabis use predicts the development of anxiety disorders, depression, suicidal ideation, certain personality disorders, and interpersonal violence. Further, associations have been found stronger in adolescents relative to adults, and younger age of initiation increases the risk of developing mental health disorders. Cannabis use among youth remains prevalent, and recent studies are consolidating previous findings that adolescents are especially vulnerable to mental health disorders associated with cannabis. This suggests that cannabis involvement requires increased prominence in research, prevention initiatives, routine screening, and interventions to improve adolescent mental health.

An age–period–cohort analysis of cannabis use prevalence and frequency in Germany, 1990–2009

BackgroundIn order to better understand trends in cannabis use, this study estimates independent and non-confounded age, period and cohort effects on 12-month cannabis use prevalence and frequency.MethodsData from seven waves...

The contribution of research to the development of a national cannabis policy in Australia

To describe the formulation of a National Cannabis Strategy in Australia in 2006 and discuss the contribution that research evidence has made to its development. A description of trends in cannabis use in Australia and policy responses to it from the early 1970s to the present, with an analysis of the evidence and arguments that have been used to support competing policies towards cannabis use. In 1977 an Australian Senate Committee recommended that a national cannabis policy should be developed that removed criminal penalties for personal possession and use. The arguments for the recommendation echoed those used to support similar earlier recommendations made in Canada, the Netherlands, the United Kingdom and the United States in the late 1960s and early 1970s. They were reiterated by a National Cannabis Task Force in 1994, but a national cannabis strategy was not developed until 2006. By default, the strategy supported continued prohibition on the production and sale of cannabis, and left penalties for cannabis use to state governments. It advocated public education campaigns to discourage young people, especially those at high risk, from initiating cannabis use, and to reduce the progression to regular use among young people who had used cannabis. It also supported efforts to reduce the availability of cannabis and to improve treatment for problem cannabis users. The research evidence which was cited as motivating the development of a national cannabis policy was epidemiological data on rising rates of use among young people, and emerging evidence from longitudinal studies in Australian and New Zealand that some adolescent cannabis users experienced harm as a result of their use. The impact that research evidence has had on Australian cannabis policy over the past three decades has, as in many comparable countries, been constrained by the limited policy options under consideration, and by the fact that interpretation of the evidence has been contested by advocates of the limited policy options under debate.

Potency of Δ9–THC and Other Cannabinoids in Cannabis in England in 2005: Implications for Psychoactivity and Pharmacology*

Gas chromatography was used to study the cannabinoid content ("potency") of illicit cannabis seized by police in England in 2004/5. Of the four hundred and fifty two samples, indoor-grown unpollinated female cannabis ("sinsemilla") was the most frequent form, followed by resin (hashish) and imported outdoor-grown herbal cannabis (marijuana). The content of the psychoactive cannabinoid delta 9-tetrahydrocannabinol (THC) varied widely. The median THC content of herbal cannabis and resin was 2.1% and 3.5%, respectively. The median 13.9% THC content of sinsemilla was significantly higher than that recorded in the UK in 1996/8. In sinsemilla and imported herbal cannabis, the content of the antipsychotic cannabinoid cannabidiol (CBD) was extremely low. In resin, however, the average CBD content exceeded that of THC, and the relative proportions of the two cannabinoids varied widely between samples. The increases in average THC content and relative popularity of sinsemilla cannabis, combined with the absence of the anti-psychotic cannabinoid CBD, suggest that the current trends in cannabis use pose an increasing risk to those users susceptible to the harmful psychological effects associated with high doses of THC.

Cannabis and schizophrenia: model projections of the impact of the rise in cannabis use on historical and future trends in schizophrenia in England and Wales

To estimate long-term trends in cannabis use and projections of schizophrenia assuming a causal relation between cannabis use and schizophrenia. Trends in cannabis use were estimated from a national survey, 2003; and incidence of schizophrenia was derived from surveys in three English cities, 1997-99. A difference equation cohort model was fitted against estimates of schizophrenia incidence, trends in cannabis exposure and assumptions on association between cannabis and schizophrenia. The model projects trends in schizophrenia incidence, prevalence and attributable fraction of cannabis induced schizophrenia. Between 1970 and 2002 cannabis exposure increased: incidence by fourfold; period prevalence by 10-fold; and use among under 18-year-olds by 18-fold. In 1997-99 incidence and prevalence of schizophrenia were 17 per 100 000 and 0.63% among men and 7.3 per 100 000 and 0.23% among women, respectively. If cannabis use causes schizophrenia, earlier increases in cannabis use would lead to increases in overall schizophrenia incidence and prevalence of 29% and 12% among men between 1990 and 2010. By 2010 model projections which assume an association between schizophrenia and light and heavy users suggest that approximately one-quarter of new schizophrenia cases could be due to cannabis, whereas if the association is twofold and confined to heavy cannabis users, then approximately 10% of schizophrenia cases may be due to cannabis. If cannabis use causes schizophrenia, and assuming other causes are unchanged, then relatively substantial increases in both prevalence and incidence of schizophrenia should be apparent by 2010. More accurate data on cannabis consumption and future monitoring of schizophrenia are critical.

Trends in cannabis use and its determinants among teenagers in the French-speaking community of Belgium

Cannabis consumption among teenagers has undergone dramatic changes in Europe since the beginning of the 1990s. A number of behaviors associated with cannabis consumption, such as tobacco smoking, excessive drinking and truancy are developing too, each in their own way. To assess the evolution over time of the various types of cannabis consumption (both ever and weekly consumption) in relation to these determinants (age, sex, studies chosen, truancy, tobacco smoking and recurrent intoxication), we have analyzed the cross-sectional study on Health Behaviour in School-Aged Children in the French-speaking Belgian Community (12-17 years) since 1994. We used logistic models to analyze the evolution of the various types of cannabis consumption and to identify the associated factors. Finally, in order to demonstrate time trends, we tested for each type of consumption in the interactions between the significant predictive variables in each model and the survey year (1994-1998-2000). Rates of ever use, past 30-day use and weekly use among the ever users have been increasing from 1994 to 2002 and reached, respectively, 22.0%, 11.6%, 6.8% and 32.9%. Cannabis ever use rose more noticeably among the general education students (adjusted OR (95%CI)): 3.08 (2.66-3.57) and among the truants: 4.57 (3.39-6.14). Weekly cannabis smoking rose most especially among the truants: 1.92 (1.34-2.78). Truants should constitute a priority target for the prevention of cannabis consumption, while the phenomenon of truancy must be moreover examined in depth in order to more thoroughly identify the appropriate prevention programs organized both in and outside of the school environment.

Dutch coffee shops and trends in cannabis use

Conflicting predictions have been made to the influence of decriminalization on cannabis use. Prohibitionists forecast that decriminalization will lead to an increase in consumption of cannabis, while their opponents hypothesise that cannabis use will decline after decriminalization. Most probably cannabis use in the Netherlands so far evolved in two waves, with a first peak around 1970, a low during the late 1970s and early 1980s, and a second peak in the mid-1990s. It is striking that this trend in cannabis use among youth in the Netherlands rather parallels four identified stages in the availability of cannabis. The number of cannabis users peaked when the cannabis was distributed through an underground market (late 1960s and early 1970s). Then the number decreased as house dealers were superseding the underground market (1970s), and went up again after coffee shops took over the sale of cannabis (1980s), and stabilised or slightly decreased by the end of the 1990s when the number of coffee shops was reduced. Although changes in cannabis policy went along with changes in availability of cannabis and prevalence of cannabis use, it is questionable whether changes in cannabis policy were causally related to trends in cannabis use. Cannabis use also developed in waves in other European countries that did not decriminalize cannabis, as well as in the US. Consequently, trends in cannabis use seem to develop rather independently of cannabis policy.

Cannabis use among Australian adolescents: findings of the 1998 National Drug Strategy Household Survey

ObjectiveTo describe the prevalence, context and recent trends in cannabis use among Australian adolescents. MethodData was collected from 1,581 adolescents aged 14–19 years as part of the 1998 National Drug Strategy Household Survey, and comparisons were made with data from 350 adolescents who participated in the 1995 survey. ResultsAmong 14–19 year olds, 47.8% have had the opportunity to use cannabis in the past year and 45.2% have used cannabis at least once in their lifetime. Substantial increases have occurred since 1995 in the prevalence of use among young females. While most cannabis use was fairly infrequent, a minority of 14–19 year olds (9.4%) used cannabis at least weekly. Cannabis use was associated with regular tobacco and alcohol use, and other illicit drug use. Regular cannabis users had lower levels of health on the general health and vitality dimensions of the SF‐36. ImplicationsThese results show that cannabis availability and use is common among Australian adolescents, and confirm that there has been an increase in use between 1995 and 1998, although only among young females. Future research is required to understand why this recent increase has occurred, and trends in cannabis uptake and use patterns among this group should be carefully monitored. Interventions may need to be developed and made available to the group of young people who are using cannabis heavily.

The recent Australian debate about the prohibition on cannabis use

This paper outlines the ethical arguments used in the Australian debate about whether or not to relax the prohibition on cannabis use by adults. Over the past two decades a rising prevalence of cannabis use in the Australian population has led to proposals for the decriminalization of the personal use of cannabis. Three states and territories have removed criminal penalties for personal use while criminal penalties are rarely imposed in the remaining states. Libertarian arguments for legalization of cannabis use have attracted a great deal of media interest but very little public and political support. Other arguments in favour of decriminalization have attracted more support. One has been the utilitarian argument that prohibition has failed to deter cannabis use and the social costs of its continuation outweigh any benefits that it produces. Another has been the argument from hypocrisy that cannabis is less harmful than alcohol and so, on the grounds of consistency, if alcohol is legally available then so should cannabis. To date public opinion has not favoured legalization, although support for the decriminalization of personal cannabis use has increased. In the long term, the outcome of the debate may depend more upon trends in cannabis use and social attitudes among young adults than upon the persuasiveness of the arguments for a relaxation of the prohibition of cannabis.

Recent trends in cannabis use in Canada

This paper reviews surveys of cannabis use in Canada carried out in the last decade and presents the findings of a nation-wide adult survey carried out in January, 1978. The main findings of the latter survey were as follows: 1. (1) 17.2% of the sample reported that they has used marihuana and/or hashish at some time in their lives; 2. (2) 9.7% reported that they had used cannabis in the past 12 months; 3. (3) 3.6% reported that they had used cannabis more than once a week in the past 30 days; 4. (4) The period 1970–1973 was most often reported as the time of initiation of cannabis use, followed by the period 1974–1977. 5. (5) There were significant differences between regional and social groups in reported patterns of cannabis use. Specifically: • — Residents of British Columbia, young people, males, labourers, persons whose mother tongue was English, residents of larger communities and those with high-school or university education were more likely to report that they had “ever used” marihuana; • — The same patterns held for use of cannabis in the “past 12 months”, with the exception of education which did not show significant differences; • — The same patterns as noted for use of cannabis in the past 12 months also held for use “more than once weekly” in the past 30 days with the exception that there were no significant differences between residents of various sized communities or those with different mother tongues. It was concluded that there has been an increase in cannabis use in Canada over the past decade, the exact magnitude of which is unknown and probably unknowable given limitations of previous research. On the other hand, the data suggest that the rate of increase may have slowed in the past few years.

The role of the pharmacist in …: Sports Medicine

In this contribution, I summarize recent trends of cannabis use in Europe and their public health implications. The first trend refers to an increase of treatment demand for cannabis problems by 76% while prevalence of cannabis use remained largely stable in the same period, based on available data. There are good reasons to assume that this trend reflects increases in the prevalence of cannabis use disorders, however, data to support this claim are not available. Potential drivers for a rising prevalence of cannabis use disorders comprise changes in consumption patterns and increasing levels of THC in available cannabis products. While an increasing prevalence of cannabis use disorders seem likely, the estimates of the Global Burden of Disease studies suggest the opposite. The second trend refers to an emerging market for cannabidiol (CBD) products in European countries, where regulations on CBD are lacking. Given the lack of data on users of CBD products, it can hardly be assessed if current abstainers will initiate using other cannabis products after trying CBD products for medicinal or recreational purposes. However, regulations should be implemented and enforced in order to make CBD products safer for consumers, for instance by ensuring reliable potency levels and by reducing the presence of toxic substances through quality control measures. In summary, a substantial transition of the epidemiology of cannabis use is under way, accompanied by changes in potency, treatment demand and new products. In order to assess the public health implications of this transition, data on population exposure of specific cannabinoids are required.