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Cannabis-Gateway Revisited Special


A great deal of my work with young people draws n research that demonstrates that drug and alcohol use evolves through the interplay of multiple risk factors. Risk factors are accumulative in the lives of young people. This means that that young people are born with a back ground set of risk factors such as poverty, temperament, family norms, postcode and peer sensitivity. Whilst this increases the probability of drug and alcohol involvement it does not pre-determine their involvement. This requires a set of initiation factors such as positive expectations of use, availability within peer groups and weak pro-social attachments. Once young people do initiative use, a wider set of risk factors then comes into play. As such, drug and alcohol snowballs across adolescence in small degrees.

Involvement in recent decades has always tend to follow a broad sequence of tobacco, alcohol and then cannabis. Critical in this is the age of initiation in use. The early that a young person begins to use substances, then the longer and heavier their subsequent using career tends to be. involvement tends to be. A clutch of recent studies have both demonstrated that this continuum still occurs, but with some changes.

What a difference a year or two can make:

A recent study has shown that if you started smoking marijuana at the start of your teens, your risk of having a drug abuse problem by age 28 is 68 per cent, but if you started smoking between 15 and 17 your risk drops to 44 per cent, according to a new study by Université de Montréal researchers.

All the more reason, they say, to educate kids early, in primary school, about the risks of starting pot smoking, especially now that the potency is much greater than it was in decades past and that public acceptance is being spurred by legalization in jurisdictions such as Canada. "The odds of developing any drug abuse symptoms by age 28 were reduced by 31 per cent for each year of delayed onset of cannabis use in adolescence," the researchers at UdeM's Department of Psychology, School of Psychoeducation and the CHU Saint-Justine Hospital Research Centre found. Their study was published April 22 in the Canadian Journal of Psychiatry.

According to a 2011 study by University of Waterloo researchers in the journal Addictive Behaviors, 10 per cent of Canadian adolescents consumed cannabis in Grade 8. By Grade 12, that percentage nearly tripled to 29 per cent. Early-onset cannabis use has been linked to further drug abuse problems later in life.

The new study, done by UdM doctoral student Charlie Rioux under the supervision of professors Natalie Castellanos-Ryan and Jean Séguin, shows just how much.

The researchers looked at data for 1,030 boys in the Montreal Longitudinal and Experimental Study of white francophones from some of the city's impoverished neighbourhoods begun in the early 1980s. Every year between ages 13 and 17, the boys were asked if they had consumed cannabis at all in the previous year.

At 17, and again at 20 and 28, they were asked not only whether they consumed cannabis, but also other drugs, including hallucinogens, cocaine, amphetamines, barbiturates, tranquilizers, heroin and inhalants. Then the data were correlated with the age at which they started using cannabis. The results confirmed the researchers' suspicions: the younger they started, the more likely the boys had a drug problem later as young men. This is partly explained by the frequency with which they consumed cannabis and other drugs, but those who started before age 15 were at higher risk regardless of how often they consumed. "The odds of developing any drug abuse symptoms by age 28 were non-significant if cannabis use had its onset at ages 15 to 17, but were significant and almost doubled each year if onset was before age 15," the study says. Even if those who start smoking cannabis at 17 years were at lower risk, frequent users (20 or more times a year) at age 17 had almost double the chance of abuse by age 28 than occasional users.

And that may be underestimating the problem, the researchers say. "Notably, considering that the potency of cannabis products increased over the last two decades and that [inthis study] adolescent cannabis use was assessed from 1991 to 1995, it is possible that the higher content of 9-tetrahydrocannabinol in the cannabis available today would be associated with higher rates of drug abuse symptoms."

The researchers also found that the earlier that boys were involved in gangs, drank alcohol, got into fights, stole or vandalized property, the earlier they used cannabis and the higher their odds of having drug abuse issues by 28. Those who started drinking at 17 also were at higher risk of having an alcohol problem at 28.

The finding that starting pot smoking between ages 13 and 15 increases the odds of developing a drug problem later on makes it all the more important to prevent or reducing cannabis use as early as possible, the researchers say. "It may be important to implement these programs by the end of elementary school to prevent early onset of cannabis use," said Rioux. "Since peer influence and delinquency were identified as early risk factors for earlier cannabis onset and adult drug abuse, targeting these risk factors in prevention programs may be important, especially since prevention strategies working on the motivators of substance use have been shown to be effective."

(Materials provided by University of Montreal. Charlie Rioux, Natalie Castellanos-Ryan, Sophie Parent, Frank Vitaro, Richard Ernest Tremblay, Jean Richard Séguin. Age of Cannabis Use Onset and Adult Drug Abuse Symptoms: A Prospective Study of Common Risk Factors and Indirect Effects.)

Another study has found that the tobacco-alcohol-cannabis sequence is being challenged. More young people are turning to marijuana as their first substance of choice, rather than smoking cigarettes or drinking alcohol. This pattern is especially prevalent among young men of specific racial and ethnic groups in the US, says Brian Fairman of the National Institute of Child Health and Human Development in the US, in Springer's Journal Prevention Science. He says that young people who start off on marijuana before alcohol or tobacco are more likely to become heavy users and have cannabis-related problems later in life.

The research team analyzed nationally-representative, cross-sectional survey data available as part of the US National Survey on Drug Use and Health. This data draws on information from more than 275,500 individuals aged 12 to 21 and was collected between 2004 and 2014. Survey respondents were asked about their use of marijuana, cigarettes, alcohol, and other forms of tobacco or illegal drugs. Those who used these substances provided further information about which they started using first, and at what age.

The researchers found that 8 per cent of participants reported in 2014 that marijuana was the first drug they ever used. This percentage had almost doubled from 4.8 per cent in 2004. According to Fairman, this could be related to a concurrent decline in those who start smoking cigarettes first, which dropped from about 21 per cent in 2004 to 9 per cent in 2014.

"We also observed a significant increase in youth abstaining from substance use altogether, which rose from 36 per cent to 46 per cent, and therefore, it is unclear the degree to which increases in those initiating marijuana first could be due to youth abstaining or delaying cigarettes," says Fairman.

Fairman and his colleagues further found that those using marijuana first, rather than alcohol or cigarettes, were more likely to be male, and Black, American Indian/Alaskan Native, multiracial, or Hispanic. The researchers established that youths who used marijuana first were more likely to become heavy users later in life, and to develop a cannabis use disorder.

"Our findings suggest important targets for public health intervention and prevention of marijuana use, especially among American Indian/Alaska Native and Black youth, who are less likely to have access to treatment or successful treatment outcomes," says Fairman, who believes that drug prevention strategies could be improved by targeting to groups differently, based on their risk of initiating tobacco, alcohol, or marijuana first. "To the degree these trends continue and greater numbers of youth start with marijuana as their first drug, there may be an increasing need for public interventions and treatment services for marijuana-related problems," Fairman explains.

(Materials provided by Springer. Journal Reference: Brian J. Fairman, C. Debra Furr-Holden, Renee M. Johnson. When Marijuana Is Used before Cigarettes or Alcohol: Demographic Predictors and Associations with Heavy Use, Cannabis Use Disorder, and Other Drug-related Outcomes. Prevention Science, 2018)

One reason for this might be the shift in cannabis availability in the US. Adolescents who view more advertising for medical marijuana are more likely to use marijuana, express intentions to use the drug and have more-positive expectations about the substance, according to a new RAND Corporation study.The findings -- from a study that tracked adolescents' viewing of medical marijuana ads over seven years -- provides the best evidence to date that an increasing amount of advertising about marijuana may prompt young people to increase their use of the drug. The study was published by the journal Drug and Alcohol Dependence.

"This work highlights the importance of considering regulations for marijuana advertising that would be similar to rules already in place to curb the promotion of tobacco and alcohol across the United States," said Elizabeth D'Amico, the study's lead author and a senior behavioral scientist at RAND, a nonprofit research organization.Researchers say the issue is of increasing importance because 29 states and Washington D.C. have approved sales of medical marijuana, and nine states and Washington D.C. also have approved recreational sales of the drug. Both actions are likely to lead to more marijuana advertising that will be visible to adolescents, even if they are not the target of the ads.

The RAND study followed 6,509 adolescents from 2010 until 2017 who were originally recruited from 16 middle schools in three school school districts in Southern California, and went on to more than 200 high schools in the region. Participants were periodically surveyed to assess their exposure to medical marijuana advertising, and asked about marijuana use and related topics.The participants were ethnically diverse. and rates of marijuana use at the outset of the study were similar to national samples of adolescents.The proportion of adolescents who reported viewing medical marijuana advertising increased sharply over the course of the study. In 2010, 25 percent of the participants reported seeing at least one medical marijuana advertisement during the previous three months -- the exposure rate grew to 70 percent by 2017.Adolescents who reported greater exposure to medical marijuana advertising were more likely to report having used marijuana over the previous 30 days, and were more likely to report that they expected to use marijuana during the next six months.

Viewing more medical marijuana advertising also was associated with having more-positive views about the drug, such as agreeing that marijuana relaxes a person and helps a person get away from their problems.Youth who were exposed to more medical marijuana advertising also were more likely to report negative consequences because of marijuana. This included missing school, having trouble concentrating on tasks, doing something they felt sorry for later or having gotten into trouble at school or home."Our findings suggest that increased exposure to medical marijuana advertising is associated with increased marijuana use and related negative consequences throughout adolescence," D'Amico said. "Thus, it is possible that teens who were exposed to the most medical marijuana advertising were more likely to use marijuana heavily and therefore experience more negative consequences."Researchers say that future research should look more closely at the impact of different sources of marijuana advertising, such as billboards, magazine ads or signage at retail outlets."

As more states legalize marijuana for medical or recreational uses, we must think carefully about the best ways to regulate marijuana advertising so that we can decrease the chances of harm occurring, particularly for adolescents," D'Amico said. "We must also continue to address beliefs about the effects of marijuana as part of our prevention and intervention efforts with this age group.

(Materials provided by RAND Corporation.Journal Reference:Elizabeth J. D’Amico, Anthony Rodriguez, Joan S. Tucker, Eric R. Pedersen, Regina A. Shih. Planting the seed for marijuana use: Changes in exposure to medical marijuana advertising and subsequent adolescent marijuana use, cognitions, and consequences over seven years. Drug and Alcohol Dependence, 2018;)


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