Keywords

1 Drug Use Prevalence in the General and Target Populations

Various indicators allow assessing drug use and its correlates in youngsters, such as the prevalence of lifetime or recent use of different substances in the general population, regular, problem drug use, high-risk drug use, frequency of use, age of substances’ use initiation as well as the perception of potential risks and benefits of drugs by young people. However, these indicators merely provide a fragmented picture of the complex and changing bond between psychoactive substances and their users or potential users in a given era and socio-cultural environment. Moreover, national data might not be available, not representative or not comparable to previous data or to data from other countries, due for instance to divergent methodologies or data formatting.

This said, data from representative general population surveys provide a sound framework to discuss patterns of drug use in the general population. Although national data from a series of selective surveys on various target groups at regional or national levels are available, the latter are either outdated or too specific to provide meaningful input to the present analysis.

To date, the sole representative national data on drug use in the general population of Luxembourg stems from the 2014 wave of the European Health Interview Survey (EHIS). Prevalence rates of substance use in age group 15–34 years are presented in Fig. 1. Cocaine and ecstasy-type substances appear to be the most used controlled substances (cannabis excluded) in residents aged 15–34 years. Drug prevalence rates applied to age group 15–18 years are not included in Fig. 1 as the latter equal to 0.0% for retained substances (except for LSD: 0.6%).

Fig. 1
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Source EHIS (2014)—Origer (2018)

Life-time, last 12 months and last 30 days prevalence of various psychoactive substances’ use (cannabis excluded) according to age 15–34 years (2014) (valid %).

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Cannabis is the most used controlled psychoactive substance at the national level, and thus deserves special attention, notably because of its use prevalence in youngsters. Figure 2 provides an overall picture of national cannabis use prevalence in the general population according to age groups 15–18 years and 15–34 years, based on EHIS data.

Fig. 2
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Source EHIS (2014)—Origer (2018)

National life-time (LTP), last 12 months (LYP) and last 30 days (LMP) prevalence of cannabis use according to different age groups (valid %).

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To put these results in a European perspective, a comparison with comparable prevalence data from other EU member states has been performed. According to available 2014/2015 data (EMCDDA 2015), national last 12 months prevalence and last 30 days prevalence of cannabis use situate below the EU average and below respective rates in border countries of Luxembourg.

Table 1 shows that first substance use most frequently occurs in age group 15–19 years, with the exceptions of heroin and cocaine, for which first use typically occurs between 20 and 24 years. Virtually, half of youngsters use cannabis for the first time while being still minor of age.

Table 1 Age distribution of first substance use. Source EHIS (2014)—Origer (2018)
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A longitudinal analysis of prevalence trends in the general population cannot be performed since serial data on drug use at the national level are unavailable to date. In contrast, data from school survey allow, to a certain extent, a more in-depth analysis of the evolution of drug use in youngsters over the last decades.

First representative school surveys including national data on drug use have been conducted as early as 1992 (Matheis et al. 1995). However, only the first national wave of the Health Behavior in School Children (HBSC) survey in 1999 and subsequent serial surveys allowed to validly compare national prevalence data in a longitudinal perspective.

When looking specifically into younger age groups, data from the HBSC study suggest that, among 15–16 years-old, lifetime consumption of illicit drugs has been generally decreasing since 1999, with the notable exception of cocaine use (Fig. 3). As to the age group 13–14 years, similar trends can be observed with the exceptions of cocaine, showing a decreasing use prevalence, and cannabis use, which has been remarkably stable between 2006 and 2014, following a marked decrease compared to 1999 data.

Fig. 3
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Source HBSC 1999–2014, Université du Luxembourg, Ministère de l’Education Nationale, de l’Enfance et de la Jeunesse, Ministère de la Santé (2002, 2018)

Life-time prevalence of psychoactive substances’ use according to age groups 13–14 years and 15–16 years (1999–2014) (valid %).

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Between 1999 and 2006, last 12 months consumption of cannabis in 15 and 16 years old schoolchildren has been decreasing. Moreover, last 12 months cannabis use prevalence shows a discontinuous decrease for 15 years old and a fair stability for 16 years old between 2006 and 2014 (Fig. 4). As for other controlled substances, cocaine use has been showing a slight increase and ATS and LSD use have been witnessing a decrease in both 15 and 16 old students between 1999 and 2010. No serial last 12 months prevalence data for substances other than cannabis are available for 2014.

Fig. 4
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Source HBSC 1999–2014, Université du Luxembourg, Ministère de l’Education Nationale, de l’Enfance et de la Jeunesse, Ministère de la Santé (2002, 2018)

Last 12 months prevalence of psychoactive substances’ use according to age groups 15 years and 16 years (1999–2014) (valid %).

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Figure 5 shows trends in lifetime, last 12 months and last 30 days prevalence of cannabis use in students aged 13 to 18 years between 2006 and 2014.

Fig. 5
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Source HBSC 1999–2014, Université du Luxembourg, Ministère de l’Education Nationale, de l’Enfance et de la Jeunesse, Ministère de la Santé (2002, 2018)

Lifetime, last 12 months and last 30 days prevalence of cannabis use according to age group 13–18 years (2006–2014) (valid %).

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Last 30 days cannabis use prevalence rates in schoolchildren aged 15 to 18 years, provided by serial HBSC data, have been witnessing an overall increase between 2006 and 2018 (see Fig. 6). A more in-depth analysis has revealed that the increase is statistically significant overall and for girls and that according to specific age groups, cannabis use appears to have been decreasing in younger adolescents (i.e. 15 years) whereas increasing in higher age groups (i.e. 16/17/18 years) since 2006.

Fig. 6
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Source HBSC 2018, Heinz et al. (2019)

Last 30 days prevalence of cannabis use according to age group 15–18 years (2006–2018) (valid %).

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In summary, data from general population and school surveys suggest that national drug use prevalence in younger residents (i.e. 15–34) situates below the EU average and that drug use in youngsters aged between 13 and 16 years has been generally decreasing since the beginning of the 21st century, except for cocaine in the age group 15–16 years. More detailed national data are available for cannabis use in youngsters between 2006 and 2018. Whereas lifetime and last 12 months use of cannabis in students aged 13–18 years have been stable as a whole during the referred period, recent cannabis use (last 30 days) has been witnessing an overall increase between 2006 and 2018. In terms of international comparison, HBSC data (Inchley et al. 2016) have shown that 15 years old girls and boys in Luxembourg report both a lifetime prevalence of cannabis use of 18%, which appears to be higher than the HBSC average of 13% for girls and 17% for boys.

2 High-risk Drug Use

Problem drug use (PDU) or high-risk drug use (HRDU)Footnote 1 are further indicators to measure drug use prevalence and drug use patterns in a given population or target group. The number of high-risk drug users has been estimated at 2250 persons based on 2015 national data (Origer et al. 2018) at the national level, which equals to a national prevalence rate of 5.79 high risk drug users in 1000 inhabitants aged 15–64 years. A more recent study on 2018 data, (Berndt et al. 2021) tends to confirm the general downward trend of national HRDU prevalence observed since 2003 (2018: 5.02 HRD users in 1000 inhabitants aged 15-64 years).

According to national drug monitoring data (RELIS), the average age of HRDU has been increasing from 28 years and 4 months in 1995 to 38 years and 6 months in 2017. After a closer look at age distributions over time, it appears that the obvious aging of the national HRDU population is primarily due to a marked increase in the proportion of users aged 40 years and more and to a decreasing proportion of users aged 20 to 29 years and not to any genuine trend in younger users aged 15–19 years. Moreover, the average age of first illicit drugs’ use by current HRD users has been increasing from 15 years in 2008 to 16 years in 2017. This observation contrasts with markedly higher average ages of first dug use in the general population (see Table 1).

3 Drug Supply, Quality and Price

On the supply side, special attention is due to cannabis when it comes to drug use in youngsters. Average Δ9-tetrahydrocannabinol (THC) concentration in cannabis products available on the national illicit market has been increasing over the last decade and is continuing to do so. Maximum concentrations of THC in national samples of cannabis show the same trend as can be seen in Fig. 7, knowing, however, that these very high concentrations are currently exceptional and mostly related to specific extraction methods (e.g. butane hash oil, dab, shatter). Similar evolutions have been observed in the EU, where cannabis resin and herb potencies have been increasing by 122% and 82% respectively between 2008 and 2020, whereas prices of cannabis resin and herb at retail level have known an increase of 12% over the same period (EMCDDA 2018, 2020). In other words, cannabis users tend to getting more THC for less money over recent years (Fig. 8).

Fig. 7
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Source LNS (2020)

Average and maximum THC concentrations in cannabis (resin and herbal) in Luxembourg from 2006–2019 (%).

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Fig. 8
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Source EMCDDA (2020)

Cannabis price and potency in Europe 2008–2018.

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Moreover, new varieties of cannabis have been appearing on the illicit market with high levels of THC and low levels of cannabidiol (CBDFootnote 2). Knowing that emerging evidence suggest that CBD may have the capacity to reduce the psychoactive potential of THC (Wall 2019), these newer varieties are more ‘potent’ than varieties with similar THC levels but higher CBD concentrations. These emerging cannabis products as well as the average increase of THC concentrations in cannabis not only bear greater risks in terms of immediate psychological and behavioral effects but also in terms of cerebral maturation and the development of cognitive functions such as working memory, decision-making, impulsivity control, motivation and of mental health in general, according to the frequency of use.

Purity is one aspect of quality; impurity is another one. Drugs sold on the illicit market are knowingly of diverse and changing quality. They may contain cutting agentsFootnote 3 and other adulterants (Solomini et al. 2017). As far as cannabis is concerned, a considerable variety of impurities has been found in samples worldwide over recent years, including sand, soil, shoe wax, hairspray, henna, glass beads, lead, talcum, etc. Moreover, street cannabis and its derivatives may be contaminated for instance with pesticides, heavy metals, bacteria, fungi and mycotoxins (Buchicchio et al. 2022). A more recent emerging trend that is bearing increased risks appears to be the adulteration of cannabis products with synthetic cannabinoid receptor agonists (Oomen et al. 2022).

As the very characteristics of cannabis and cannabis products have been changing markedly over recent years, the ‘image’ of cannabis has equally known substantial re-adjustments. Research on the nature and components of cannabis and its potential applications for health related matters, and the fact that an increasing number of countries or jurisdictions throughout the world have put or plan to put legislations in place allowing the use of cannabis and its derivatives for medical and non-medical purposes, supposedly had an impact on how people perceive cannabis and its potential risks and benefits.

Moreover, in recent years, new markets have been developing. One of these relates to cannabidiol (CBD) products, reaching from dried flowering tops of hemp containing less than 0.2% or 0.3% THC and CBD oils and extracts, to infusions and cosmetics containing CBD. Although these products do fall under various legal and regulatory frameworks, the market has been developing nervously and selling points have been proliferating, commending a wide range of beneficial proprieties of hemp and CBD. Notably via CBD, hemp-based products may have created confusion and more importantly curiosity, interest, visibility and supposedly increased acceptance in the general population.

4 Drug Demand, Risk Assessment, Pattern of Use and Trends

This having been said, cannabis and related products sold on the illicit market bear increasing risks, while cannabis as such tends to be perceived as more beneficial, useful and potentially less harmful than half a century ago when cannabis was put in the very same and most restrictive schedules of relevant UN conventions as heroin or desormorphine for instance. These evolutions in somehow opposite directions need to be addressed also because of their likely impact on the perceptions, risk assessment, choices and behaviors of young people, users and potential users. As a matter of fact, the risk perception of cannabis use seems to have changed in EU youngsters aged 15 to 24 years between 2001 and 2014. In 2011, 67% of responding youngsters in a EUROBAROMETER survey (European Commission 2014) considered regular cannabis use to bearing high risks while in 2014, this rate only reached 63%. The same downward trend has been observed regarding risk assessment of occasional use.

Knowing that numerous studies have found an inverse relationship between risk perception related to cannabis and the prevalence of its use (Bachman et al. 1998; Volkow et al. 2014; Compton et al. 2016; Lynskey and Hall 2016; Parker and Anthony 2018), it seems obvious that these factors and changes have to be addressed in sound prevention strategies, bearing in mind, however, that other factors such as changes in tobacco and cigarettes’ use also interfere with cannabis use prevalence (Miech et al. 2017).

As addressed earlier, drug supply and accessibility are relevant factors in the analysis of drug use patterns. Nonetheless, they do evolve according to an equally dynamic demand for psychoactive substances in the course of time.

Why do people start (or do not start) using drugs and what kind of psychoactive substances do they use for which reasons in a given era, in a given environment, during a given time of their life? These questions should be asked when investigating the bond between individuals and psychoactive substances. There seems to be evidence that the decision to use drugs by youngsters tends to be based on a ‘rational appraisal process’, rather than a passive reaction to the context in which a substance is available’ (Boys et al. 1999, 2001; Wibberley and Price 2000). Notwithstanding the potential impact of the interactions between individual genetics and life and social environments on human behaviour, one may categorise the motivation to use psychoactive substances overall in terms of pleasure, relief, and individual functions. (Allen 2003; Boys et al. 1997, 1999, 2001; Kreek et al. 2005; Parks and Kennedy 2004; Van der Poel et al. 2009).

Reasons to start using or to using psychoactive substances commonly cited in literature (Brunelle et al. 2003; McInstosh et al. 2005; Palmqvist et al. 2003; Titus et al. 2007) such as enjoyment, relaxation, curiosity and experimentation, rebellion, non-conformity, escape from reality, defense mechanisms, abuse and trauma, self-medication, boredom, solitude, grief, end of relationship, peer/social-pressure, emotional stress, professional burden, performance enhancing do all fit in one or more of these broad categories.

Moreover, as new drugs have been developed and already existing psychoactive substances have found their ways to recreational drug use over the last decades, their use has been going along with innovation in drug development and societal changes. Since 1971, the Substance Abuse and Mental Health Services Administration, an agency of the U.S. Department of Health and Human Services, coordinates the National Survey on Drug Use and Health (NSDUH), collecting data from a representative sample of U.S. households on their drinking, smoking, and illicit drug use habits. Data were analysed according to 10 different classes of substances throughout several generations of Americans: the Baby Boomers (1943–1962), Generation X (1963–1982), and Millennials (1983–2002). The data allowed to assess the prevalence of past months, past year and lifetime substances’ use according to different age groupsFootnote 4.

Detailed data analysis has been performed, but in the present context, the mere general conclusion of the surveys is at stake; namely: every generation has its trends in psychoactive substance use. Summarily, according to the authors of the analysis, alcohol is the most commonly used substance by all generations, although Baby Boomers show a higher prevalence and have started drinking earlier than other generations. Cannabis is the second most used substance in all generations, with the Baby Boomers, having lived through the 60s, once again showing highest prevalence rates. What characterises Baby Boomers most, however, is their highest use of stimulants and sedatives, which might be linked to the fact that they have lived through a post-World War II period when amphetamines were frequently prescribed as a treatment for depression before they were eventually regulated more strictly due to their widespread abuse. Moreover, in the 60s, new barbiturates were frequently prescribed for insomnia and anxiety but these drugs were progressively replaced by a broader class of medications known as benzodiazepines.

Alcohol and cannabis use of Generation X is lower than the one of the Baby Boomers but higher than the prevalence in Millennials. This said, psychotropic medications (commonly prescribed in case of mental disorders) use is highest in Generation X. This use peaked around the age of 20 years, with about 10% of Generation Xers using these drugs.

After alcohol and cannabis use, Millennials, for their part, seem to be more attracted to painkillers than any previous generation. Their peak shows over 12% painkiller use in age categories 19–20, compared to fewer than eight percent of Baby Boomers and Generation Xers. In the 70s, the prescription of opioid painkillers expanded in the US and by 2013, more than 207 million prescriptions of these medications were registered, compared to 76 million in 1991.Footnote 5 Facing the growing problem of opioid painkiller addiction and the increase of accidental opioid overdose deaths between 1999 and 2010, the US government has been undertaking a series of measures to reduce opiate painkiller use and abuse as for instance abuse-deterrent formulation of these medications. This contributed to reduce supply at street level, increase their price and lead numerous users to heroin, a less expensive and more accessible alternative to opioid prescription drugs. (Slevin and Ashburn 2011). As it stands, this is another sound example of how regulations, pharmacological developments and economic aspects may affect drug supply and demand as well as drug use and abuse patterns.

Although these data should not be generalised and applied without restriction to other countries or populations as the survey exclusively includes US citizens, they clearly show differences between generations which were exposed to different social and political contexts and innovations in drug supply/accessibility and pharmacological developments over the past 70 years.

Anther relevant example of contemporary changes might be seen in the emergence of New Psychoactive Substances (NPS). In a commercial perspective, NPS are drugs, which were designed or recovered to replicate or mimic the effects of illegal substances while not being controlled by international drug conventions by the time of their appearance on the market. They may, however, pose a public health threat comparable to that posed by substances listed in these conventionsFootnote 6.

Most of these substances have appeared in Europe in the 1990s and in the beginning of the 2000s. From 2004 onwards, synthetic cannabinoids became available on the market, followed by synthetic cathinones and others. (UNODC 2013).

Precursors and additives used in the manufacturing of NPS are often easily available because they serve other, commercial or industrial legitimate purposes and the production process generally requests reasonable means in terms of investments and knowhow. The prime ‘advantages’ of NPS compared to substances stemming from naturally grown plants are indeed multifold. Small and inconspicuous production units can be set up conveniently near consumer markets; short distances between producers and user markets, online selling with crypto currencies, small quantities but high potency of products jointly contribute to reducing ‘commercial’ risks and increasing potential benefits. These parameters together with low initial investments and modest running costs of production units are regrettably making NPS traffic an outstanding ‘business model’.

This to say that illicit drugs, their origin, their very characteristics, their price and purity and finally their targeted user groups are largely conditioned by benefits’ optimization and market rules, difficult to influence in a preventive and harm reduction perspective.

In addition, the genuine, praised or supposed legality of these substances and the multitude of expected or hoped for effects make them remarkably attractive especially to young users who may consider that if a substance is not (or said to be not) illegal, it should not be that dangerous. Unfortunately, the contrary is mostly the case. Indeed, the legal status of NPS are often blurry and rapidly changing and many of these man-made substances are potentially more dangerous than plant based drugs or long known psychoactive substances; some of which have been used and studied for decades.

5 New Information and Communication Technologies and Access to Psychoactive Substances

Availability of and access to an increasing variety of psychoactive substances have become greater. Online selling sites offer a vast range of psychoactive products, providing home delivery and customer reviews, fora and quality ratings. A large variety of psychoactive substances are accessible on the street or online. Access to drugs has probably never been that easy for younger and older regular or first users. Notably NPS and cannabis are increasingly accessible to youngsters, while potentially more harmful on the one hand, whereas various factors, addressed previously, may contribute to lower their risk assessment, on the other hand.

6 Responses

It thus appears essential that information and prevention strategies take into account the dynamic nature of the relationship between drugs, demand and supply, markets and end users.

Drugs are only one of many temptations young people are exposed to. New information and communication technologies, smart communication devices, social media, gaming and online gamingFootnote 7, etc. represent as many options and choices to make by youngsters and the risks of excessive and dysfunctional use of the latter have become more and more apparent. Information and prevention strategies should consider these evolutions and constantly adapt to emerging facts and evidence; but ideally in a holistic perspective in which drug use is only one element among others to consider. Consume behavior and wellbeing in general are at stake here. Especially young people should be supported in acquiring overall life competences and resilience based on objective and sound information as well as on skill and capacity building, notably in terms of risk and benefits assessments allowing them to make informed and responsible individual choices, regardless of the object of desire or choice.

7 Conclusions

Drugs and drug use patterns are of changing nature. There is thus no reason why responses to risks, damage and other problems related to drug use should be set in stone. The very nature of drugs are changing as are their access, their attractiveness and the perceptions of their benefits and harm potential. Numerous underlying factors such as market rules, technological innovations and societal changes are difficult to influence. Drug demand, and drug supply in the long term, may, however, be reduced if the underlying mechanisms are understood and duly taken into account.

Moreover, country specific parameters need to be addressed. Social and economic factors are potential determinants of drug use and misuse (Galea 2004; Patrick 2012). Evidence has emerged suggesting that drug abuse tends to be highest in wealthier nations (Degenhardt and Hall 2012). Knowing that Luxembourg ranks among the countries with the highest GDP per capita worldwide, these findings are of particular relevance in a national perspective. More research is needed in this regard, especially on the possible relationship between the power of purchase of youngsters, money at their disposal and drug use patterns and prevalence (Johnston et al. 1980, 1982, 1984, 1986, 2019; McCristal et al. 2007). One should also bear in mind that, more recently, the Covid-19 crises will show how drug use prevalence and patterns might have changed in youngsters also in the aftermath of a pandemic unprecedented for the current generation.

Young people start and continue to use drugs for different reasons and individual factors are clearly at stake as well when it comes to better understand why and how a behavior has become excessive and dysfunctional or addictive whether substance use is involved or any other behaviors with addictive potential. It is essential to closely monitor market evolutions in drugs’ supply as well as emerging drug use patterns and addictive behavior in general and to promote early intervention measures especially in young generations in order to timely adapt prevention and response strategies.

Additionally, although sound and objective information is needed, the means and channels by which to reach youngsters, to trigger their curiosity and to maintain their attention are equally important and require a great deal of insight in and understanding of youth culture, values, and communication forms. Combining these transient knowledge and skills in the interaction and communication with young people may be a valuable means to impact beneficially on their perceptions and reflections on their way to self-determination and informed decision making in a world of increasing possibilities, temptations, incertainty and challenges.