Do recreational cannabis users,unlicensed and licensed medical cannabis users form distinct groups?

BackgroundThis study aims to gain a more nuanced perspective on the differences between recreationally and medically motivated cannabis use by distinguishing between people who use cannabis for recreational purposes, unlicensed and licensed medical users.MethodsData collection was conducted online from a convenience sample of 1479 Israeli cannabis users. Multinomial regression analysis compared unlicensed medical users (38%) with recreational (42%) and licensed medical (5.6%) users in terms of sociodemographics, mode, frequency and problematic cannabis use.ResultsThere were more variables distinguishing unlicensed from licensed users than there were distinguishing features between unlicensed and recreational users. Recreational users were more likely to be male, less likely to eat cannabis, to use cannabis frequently and to use alone and before midday than unlicensed users. Licensed users were older than unlicensed users, they reported less hours feeling stoned, less cannabis use problems and they were more likely to report cannabis use patterns analogous of medication administration for chronic problems (frequent use, vaping, use alone and use before midday).ConclusionThis study suggests that a sizable proportion of cannabis users in Israel self-prescribe cannabis and that licensed medical cannabis users differ from unlicensed users. This is, in turn, suggestive of a rigorous medicalized cannabis program that does not function as a backdoor for legal access to recreational use. However, due to methodological limitations this conclusion is only suggestive. The most meaningful differences across recreational, unlicensed and licensed users were mode and patterns of use rather than cannabis use problems. Current screening tools for cannabis use problems may, however, not be well suited to assess such problems in medically motivated users. Indeed, when screening for problematic cannabis use there is a need for a more careful consideration of whether or not cannabis use is medically motivated.     

Can intranasal drug use reduce HCV infection among injecting drug users?

Background

Preventing HCV infection among people who inject drugs is a difficult public health challenge. We examined the potential role of intranasal drug use in reducing HCV acquisition.

Methods

Subjects were recruited from IDUs entering the Beth Israel drug detoxification program from 2005 to 2010. A structured interview was administered and serum samples were collected for HCV testing.

Results

726 active injecting drug users were recruited from 2005 to 2010. HCV prevalence was 71%, 90% reported recent heroin injection and 44% reported recent intranasal heroin use. In a multiple logistic regression analysis, being HCV seropositive was associated with more years injecting, Latino ethnicity, previous testing for HCV, and recent injection of speedball, and negatively associated with recent intranasal use of heroin (AOR = 0.52, 95% CI 0.33-0.82) and intranasal use of speedball (AOR = 0.41, 95% CI 0.31-0.80). The association between intranasal heroin use and lower HCV seroprevalance was observed among both new injectors and persons with long injecting histories (16+ years since first injection).

Conclusion

Encouraging intranasal use as an alternative to injection among persons currently injecting drugs may be a viable strategy for reducing HCV transmission.     

Dependent cannabis users at a music festival – Prevalence and correlates

Aim: In western countries, the most prevalent type of illicit substance-use dependence is cannabis dependence. This study aimed at estimating the prevalence of cannabis dependence among music festival visitors.

Methods: Based on a survey of 380 music festival guests, we estimated the prevalence of cannabis dependence, as defined by a score of 3 or more on the Severity of Dependence Scale (SDS), as well as characteristics of cannabis dependent visitors.

Results: 143 (38%) reported having used cannabis within the past year (past year cannabis users), and of these respondents, 21 (15%) screened positive for cannabis dependence. Compared to other cannabis users, the dependent respondents were more likely to be daily smokers, and they scored higher on self-reported sensation seeking. Compared with past-year non-users, both dependent users and non-dependent users were more likely to be men, weekly heavy drinkers, daily smokers and to score high on sensation seeking.

Conclusions: Out of the past-year cannabis users recruited at a music festival, one in seven of those respondents showed indication of cannabis dependence. This suggests a need for both available treatment options and primary prevention of dependence.     

Detection of Δ9-tetrahydrocannabinol in exhaled breath collected from cannabis users

Exhaled breath has recently been proposed as a new possible matrix for drugs of abuse testing. A key drug is cannabis, and the present study was aimed at investigating the possibility of detecting tetrahydrocannabinol and tetrahydrocannabinol carboxylic acid in exhaled breath after cannabis smoking. Exhaled breath was sampled from 10 regular cannabis users and 8 controls by directing the exhaled breath by suction through an Empore C(18) disk. The disk was extracted with hexane/ethyl acetate, and the resulting extract was evaporated to dryness and redissolved in 100 μL hexane/ethyl acetate. A 3-μL aliquot was injected onto the LC-MS-MS system and analyzed using positive electrospray ionization and selected reaction monitoring. In samples collected 1-12 h after cannabis smoking, tetrahydrocannabinol was detected in all 10 subjects. The rate of excretion was between 9.0 and 77.3 pg/min. Identification of tetrahydrocannabinol was based on correct retention time relative to tetrahydrocannabinol-d(3) and correct product ion ratio. In three samples, peaks were observed for tetrahydrocannabinol carboxylic acid, but these did not fulfill identification criteria. Neither tetrahydrocannabinol or tetrahydrocannabinol carboxylic acid was detected in the controls. These results confirm older reports that tetrahydrocannabinol is present in exhaled breath following cannabis smoking and extend the detection time from minutes to hours. The results further support the idea that exhaled breath is a promising matrix for drugs-of-abuse testing.     

Can HCV be prevented among injection drug users?

The hepatitis-C virus (HCV) spreads rapidly among injection drug users (IDUs) because each act of sharing injection equipment carries a high risk of transmission. IDUs are hard to reach, especially in the early stages of their drug-using careers. IDUs are also poorly organized for self-help. For these three reasons, prevention campaigns that worked against the spread of HIV among gay men will be far less effective against the spread of HCV among IDUs. The best hope for such HCV prevention lies in (1) education of middle and high school youth on parenteral risks, and (2) normalization of needle exchange.     

Are diagnostic orphans at risk of developing cannabis abuse or dependence? Four-year follow-up of young adult cannabis users not meeting diagnostic criteria

OBJECTIVE: To examine the characteristics of "diagnostic orphans" among cannabis users - those who report one or two symptoms of DSM-IV dependence but do not meet diagnostic criteria for DSM-IV abuse or dependence - 4 years post-assessment. METHOD: Data were collected from a representative population cohort of young Australian adults. Those who reported that they had used cannabis at least weekly at some point within the past year were assessed for symptoms of DSM-IV cannabis abuse and dependence using the Composite International Diagnostic Interview at age 20-21 years. The entire sample was followed up 4 years later. At age 24-25 years, cannabis use and cannabis diagnostic category were examined according to diagnostic category at age 20-21 years. RESULTS: Diagnostic orphans at age 20-21 years were more likely than non-problem cannabis users at that age to be using cannabis, and to meet criteria for cannabis abuse or dependence 4 years later. Those who had met criteria for cannabis abuse or dependence, however, appeared to be at greater risk relative to non-problematic users and diagnostic orphans of meeting criteria for cannabis abuse and dependence at follow-up. CONCLUSIONS: Young adult diagnostic orphans for cannabis use appear to be at lower risk of meeting full (or partial) diagnostic criteria after a 4-year follow-up, compared to those who had met criteria for cannabis abuse or dependence. This suggests that there is prognostic diagnostic utility in the threshold for dependence symptoms among young adult cannabis users. Diagnostic orphans did appear to be at greater risk than non-problem users for developing dependent and daily cannabis use, however, suggesting that clinicians would do well to intervene with this group.     

The effects of concurrent cannabis use among ecstasy users: neuroprotective or neurotoxic?

The research evidence regarding the potential effects of ecstasy suggests that it may be neurotoxic and that its use is associated with cognitive impairment. In recent years evidence has emerged suggesting that cannabinoids, the active ingredients in cannabis, can be neuroprotective under certain conditions. Given that many ecstasy users also consume cannabis at the same time, the possibility emerges that these individuals might be less susceptible to ecstasy-related impairment. The present paper reanalyses the data from a number of previous studies, contrasting the performance of those individuals who generally consume cannabis and ecstasy at the same time with those who generally consume ecstasy on its own. The two ecstasy-using groups are compared with non-ecstasy users on a range of measures including processing speed, random letter generation, verbal and visuo-spatial working memory span, reasoning and associative learning. The two ecstasy user groups did not differ significantly from each other on any of the measures. Both user groups were significantly worse than non-ecstasy users on measures of associative learning, verbal and visuo-spatial working memory and reasoning. The results suggest that consuming cannabis at the same time as ecstasy does not reduce the likelihood of cognitive impairment.     

Is cannabis a gateway drug? Testing hypotheses about the relationship between cannabis use and the use of other illicit drugs

We outline and evaluate competing explanations of three relationships that have consistently been found between cannabis use and the use of other illicit drugs, namely, (1) that cannabis use typically precedes the use of other illicit drugs; and that (2) the earlier cannabis is used, and (3) the more regularly it is used, the more likely a young person is to use other illicit drugs. We consider three major competing explanations of these patterns: (1) that the relationship is due to the fact that there is a shared illicit market for cannabis and other drugs which makes it more likely that other illicit drugs will be used if cannabis is used; (2) that they are explained by the characteristics of those who use cannabis; and (3) that they reflect a causal relationship in which the pharmacological effects of cannabis on brain function increase the likelihood of using other illicit drugs. These explanations are evaluated in the light of evidence from longitudinal epidemiological studies, simulation studies, discordant twin studies and animal studies. The available evidence indicates that the association reflects in part but is not wholly explained by: (1) the selective recruitment to heavy cannabis use of persons with pre-existing traits (that may be in part genetic) that predispose to the use of a variety of different drugs; (2) the affiliation of cannabis users with drug using peers in settings that provide more opportunities to use other illicit drugs at an earlier age; (3) supported by socialisation into an illicit drug subculture with favourable attitudes towards the use of other illicit drugs. Animal studies have raised the possibility that regular cannabis use may have pharmacological effects on brain function that increase the likelihood of using other drugs. We conclude with suggestions for the type of research studies that will enable a decision to be made about the relative contributions that social context, individual characteristics, and drug effects make to the relationship between cannabis use and the use of other drugs.     

Predisposed violent drug users versus drug users who commit violence: Does the order of onset translate to differences in the severity of violent offending?

Introduction and Aims. To determine whether there were differences in drug use profiles, psychopathology, and severity of violence among regular illicit drug users in respect to the order of onset of drug use and violence. Design and Methods. A cross‐sectional survey utilising self‐report data was administered to 327 regular illicit drug users in Sydney, Australia. Results. Those who first committed violent crime prior to illicit drug use were found to have more serious offending patterns (greater frequency, arrest for more serious violence, earlier age of onset, and more weapon use). Being male, having a history of child abuse and greater severity of conduct disorder were independent predictors of committing violence before drug use. Discussion and Conclusions. Whilst the nature of the data does not permit causative conclusions, it appears that the order of onset of illicit drug use and violent crime is associated with heterogeneous offending patterns. Early onset violence was associated with more severe violent crimes in later adulthood, whereas violence which proceeded drug use was more strongly linked to systemic risks. The findings have implications for early intervention among children with conduct disorder and also for using drug and alcohol treatment services to reduce specific risks associated with violence.[Torok M, Darke S, Kaye S. Predisposed violent drug users versus drug users who commit violence: Does the order of onset translate to differences in the severity of violent offending? Drug Alcohol Rev 2012;31:558–565]     

The War on Drugs—a war on drug users?

The authors argue that since the 1980s UK drug policy has largely been ill considered, reactive and counter productive. Rather than reducing drug taking and drug related crime, such policies have exacerbated the problem and contributed towards an environment in which drug use and illegal drug activities are likely to flourish. One of the consequences of this 'war on drugs' is that it manifests itself as a 'war on drug users' with an emphasis not upon the development of appropriate rehabilitative models, but upon prevention, prohibition and punishment. Drawing on the authors' qualitative research on Merseyside, England involving 200 problem drug users, it will be argued that the war on drug users has subjected these people to a process of stigmatization, marginalization and social exclusion, and prevented many of them from recovery by hindering their reintegation into the wider social and economic community. Instead, growing numbers of problematic drug users remain locked into a cycle of chronic drug relapse.     

Are illicit drug users more likely to receive mental health treatment?

Aims: The relationship between using illicit substances and seeking out mental health treatments has not been well studied. This study aimed to explore the relationship and identification of drug usage patterns related to the highest frequency of receiving mental health care. Methods: Data were obtained from the National Survey on Drug Use and Health from 2004 to 2013. Subjects were grouped according to their drug use. We examined whether there were differences between undergoing various mental health treatment and drug usage. Findings: A total of 322,869 adults were included in the study. Using a combination of analgesics and cocaine had the highest utilisation of inpatient treatment (2.9%). Using hallucinogens and cocaine showed the highest utilisation of outpatient treatment (13.3%). Those who used marijuana, hallucinogens and cocaine were most likely prescribed medicine for treatment (13.9%). There was a significant difference between drug users and non-users in all forms of mental health treatment (p?p?Conclusions: Drug use was significantly related to receiving mental health treatment and showed a significant difference when compared to non-users, but the impact of issues such as age, gender, marital status, education and race should also be considered.     

How do treatment repeaters use the drug treatment system? An analysis of injection drug users in Massachusetts

This study explored common drug treatment utilization patterns in the first four types of treatments entered by injection drug users (IDUs) with multiple admissions. A Massachusetts longitudinal database with all entries to all licensed drug treatment programs was used. Treatment repeaters' admission patterns varied considerably. For the years 1997-2001, there were 2,500-3,000 IDUs new to the system each year who became treatment repeaters and who had more than 250 utilization patterns. Only approximately half of these repeaters followed the 10 most common utilization patterns. The most common pattern (for 30% of the population each year) was only entering detoxification two to four times; the only other common pattern (involving 4-8% of the population) was having entered methadone maintenance twice or having entered detoxification then methadone maintenance. Studies are needed to identify the extent to which the absence of a systematic pattern is caused by client, payment, or treatment setting and systems issues. A key implication is the need to develop policies that provide support for states to develop continuum-of-care models for their drug treatment systems.     

Identification of drug candidates and repurposing opportunities through compound–target interaction networks

Introduction: System-wide identification of both on- and off-targets of chemical probes provides improved understanding of their therapeutic potential and possible adverse effects, thereby accelerating and de-risking drug discovery process. Given the high costs of experimental profiling of the complete target space of drug-like compounds, computational models offer systematic means for guiding these mapping efforts. These models suggest the most potent interactions for further experimental or pre-clinical evaluation both in cell line models and in patient-derived material.

Areas covered: The authors focus here on network-based machine learning models and their use in the prediction of novel compound–target interactions both in target-based and phenotype-based drug discovery applications. While currently being used mainly in complementing the experimentally mapped compound–target networks for drug repurposing applications, such as extending the target space of already approved drugs, these network pharmacology approaches may also suggest completely unexpected and novel investigational probes for drug development.

Expert opinion: Although the studies reviewed here have already demonstrated that network-centric modeling approaches have the potential to identify candidate compounds and selective targets in disease networks, many challenges still remain. In particular, these challenges include how to incorporate the cellular context and genetic background into the disease networks to enable more stratified and selective target predictions, as well as how to make the prediction models more realistic for the practical drug discovery and therapeutic applications.     

Are cannabis users who participate in a randomized clinical trial different from other treatment seekers?

Randomized controlled trials (RCTs) provide the most convincing evidence for clinical questions concerning the efficacy of interventions. When participants in RCTs are characteristically different to those in usual clinical practice, it may be difficult to generalize findings. This study compares profiles taken from a centralized intake process for those presenting with cannabis as their main drug, which were then separated into three categories, (a) those who were offered a specialist assessment for cannabis dependence over the phone but did not attend their appointment, (b) those who presented for their initial appointment, and c) those attending and subsequently recruited into an RCT. To explore whether issues such as severity of cannabis use and co-occurring disorders acted as a barrier to attending treatment or to inclusion in an RCT, we examined basic triage information. Results indicated that there were no statistically significant differences on selected characteristics between groups, suggesting that RCT participants were representative of treatment seekers, and that the filtering that occurs between those who make phone contact with professional services and those who present to treatment are not necessarily due to presence of patient characteristics such as coexisting medical, psychological issues, or severity of their cannabis use.     

Do medical cannabis laws encourage cannabis use?

Medical cannabis is a contentious issue in the United States, with many fearing that introduction of state laws will increase use among the general population. The present study examined whether the introduction of such laws affects the level of cannabis use among arrestees and emergency department patients. Using the Arrestee Drug Abuse Monitoring system, data from adult arrestees for the period 1995-2002 were examined in three cities in California (Los Angeles, San Diego, San Jose), one city in Colorado (Denver), and one city in Oregon (Portland). Data were also analysed for juvenile arrestees in two of the California cities and Portland. Data on emergency department patients from the Drug Abuse Warning Network for the period 1994-2002 were examined in three metropolitan areas in California (Los Angeles, San Diego, San Francisco), one in Colorado (Denver), and one in Washington State (Seattle). The analysis followed an interrupted time-series design. No statistically significant pre-law versus post-law differences were found in any of the ADAM or DAWN sites. Thus, consistent with other studies of the liberalization of cannabis laws, medical cannabis laws do not appear to increase use of the drug. One reason for this might be that relatively few individuals are registered medical cannabis patients or caregivers. In addition, use of the drug by those already sick might "de-glamorise" it and thereby do little to encourage use among others.     

Do drug users in China who frequently receive detoxification treatment change their risky drug use practices and sexual behavior?

BACKGROUND: Relapse rates among treated drug users in China are high. We examined the associations between frequency of drug detoxification treatment and HIV-related risky drug practices and sexual behavior. METHODS: A cross-sectional study was conducted among drug users in two Anhui province detoxification centers in 2003. RESULTS: A total of 312 drug users were recruited. Seventy-seven percent of the subjects had ever received two or more detoxification treatments. The median number of detoxification treatments received was three, with an interquartile range of two to five treatments. More than 7 in 10 (72%) ever injected drugs; 19% shared needles and syringes in the past 30 days; 40% of drug users reported having both regular and commercial sex partners in the past year and 48% reported having only regular sex partners. Multiple Poisson regression analysis documented that the frequency of detoxification treatment was not associated with a decrease in drug practice (injection or sharing needles) and in unprotected sex. CONCLUSION: Drug users who frequently received detoxification treatment did not change their risky drug use practices and sexual behavior. Effective behavioral interventions and substitution maintenance treatment should become an integral part of detoxification programs in China.     

Injection drug users’ involvement in drug dealing in the downtown eastside of Vancouver: Social organization and systemic violence

BackgroundIllicit drug markets are a key component of the risk environment surrounding injection drug use. However, relatively few studies have explored how injection drug users’ (IDUs) involvement in drug dealing shapes their experiences of drug market-related harm. This exploratory qualitative study aims to understand IDUs’ dealing activities and roles, as well as the perceived benefits and risks related to participation in illicit drug markets, including experiences of drug market violence.MethodsTen IDUs with extensive involvement in drug dealing activities were recruited from the Vancouver Injection Drug User Study (VIDUS) and participated in semi-structured qualitative interviews, which elicited discussion of experiences dealing drugs, perceived benefits and hazards related to dealing, and understandings of drug market violence.ResultsParticipant's involvement in drug market activities included corporate sales, freelance or independent sales, and opportunistic sales termed “middling” as well as drug market-related hustles entailing selling bogus drugs and robbing dealers. Participants primarily dealt drugs to support their own illicit drug use, and we found that arrest and criminal justice involvement, hazards stemming from drug debts, and drug market-related violence were key risks related to dealing activities.ConclusionThe challenges of managing personal consumption while selling drugs exacerbates the hazards associated with drug dealing. Efforts to address drug dealing among IDUs should consider both drug dependency and the material conditions that propel drug users towards dealing activities. Interventions should explore the potential of combining enhanced drug treatment programs with low threshold employment and alternative income generation opportunities.     

Web-based patient-reported outcomes in drug safety and risk management: challenges and opportunities?

Patient-reported outcomes (PROs) from web-based sources are becoming increasingly important, providing opportunities for industry and regulators to understand the benefits and risks of medicines in a real-world context. Although some guidance exists for the use of adverse event (AE) reports from company-sponsored social network sites, this does not cover non-company-sponsored sites. Additionally, there are concerns about the validity of data from social media sources. Techniques for the collection, analysis and reporting of safety data from patients should be defined, and guidelines agreed, to cover PROs and patient-reported adverse drug-related events from more organized sources of patient outcomes. This review considers drivers for web-based PRO adoption in drug safety, the current regulatory framework and potential methodologies, and concludes that there is an urgent unmet need for guidelines on web-based PRO AEs. Stakeholders for the development of any such guidance should include industry, patients, regulators, academic groups and prescribers.