Patterns of use, harm reduction strategies, and their relation to risk behavior and harm in recreational ketamine users

Development and validation of the Substance Use Protective Strategies Scale (SUPSS) among Polish young adults using various psychoactive substances

Research supports protective behavioral strategies (PBS) as effective in reducing substance use, intoxication, and/or related risks/harms. However, despite the predominance of polysubstance use and common co-occurrence of different substance use disorders (SUDs), previous PBS research has been limited in terms of substance-specific measurement. This study sought to develop and validate a measure of PBS that is not substance-specific. Building from initial pilot work, we tested the psychometric properties of the Substance Use Protective Strategies Scale (SUPSS) in a large sample of young adults (N = 7325, aged 18-30), who reported using multiple psychoactive substances (other than alcohol and nicotine), recruited via social media in Poland. By splitting the sample, we conducted exploratory (n = 3709) and confirmatory factor analysis (n = 3614), which supported a 4-factor structure with 19 items (7 items dropped): Preparation for use (α = 0.66), Manner of use (α = 0.85), Additional concerns (α = 0.74), and Setting (α = 0.62). Configural, metric and scalar invariance were supported across sex, age, and user status for most substance types (cannabis, dissociatives, etc.). Further, the SUPSS factors were strongly associated with substance-related harms (R-squared = 0.495) and SUD symptoms (DUDIT, R-squared = 0.570). Our model fit was adequate (but not excellent), and two subscales had low internal consistency, highlighting the need for further improvement of the SUPSS. Despite its limitations, we found the SUPSS to have strong psychometric properties and it holds promise to enhance PBS research and harm reduction-oriented interventions.

Past-Year Ketamine Use: Evidence from a United States Population, 2015-2019

Ketamine is an analgesic that has gained notoriety in nightclub scenes. Yet, a paucity of research exists on the prevalence and associated factors in the United States (US). The present study estimated the prevalence of past-year ketamine use among a national sample of US adults and investigated sociodemographic characteristics and past-year use of other substances associated with past-year ketamine use. Data from the 2015-2019 National Survey on Drug Use and Health was conducted among 210,392 adults over the ages of 18 years old. An estimated 0.13% of adults used ketamine in the past year, with males more likely to use. Significant risk factors included past-year drug use and sexual minority status, with sexual minority males reporting more than use of one substance at highest risk for ketamine use. Findings from the present study may inform harm reduction efforts and policy initiatives.

Clinical and behavior characteristics of individuals who used ketamine

This study aims to depict and compare clinical characteristics and risk behavior among groups of individuals using ketamine, polydrugs or smoking cigarette. A total of 185 drug-using participants and 49 smokers participated in this study. A cross-sectional interview was used to collect information on demographics, drug- and sex-related behaviors, HIV serostatus, lower urinary tract symptoms (LUTS), behavioral dispositions. N-back memory test was used to measure short-term memory. Result shows that 10 participants (5.41%) were HIV positive and 14 (7.57%) having LUTS. Individuals with ketamine and polydrugs use have significantly worse drug-related problem than cigarette smokers. Compared to cigarette smokers and ketamine users, individuals with polydrug users scored significantly higher on impulsivity measures. Cigarette smokers performed significantly better than the other two groups on the memory tests. A few patients had been infected with HIV and diagnosed with LUTS. Findings support that memory on short term recalls of patients with ketamine use might be impaired. Study findings warrants the necessarily of further study on influences of using ketamine.

"It'll Never Be Safe, But You Can Limit the Harms". Exploring Adolescents' Strategies to Reduce Harms Associated with Psychoactive Substance Use

Introduction: Harm reduction strategies are behaviors that may be applied in order to reduce adverse consequences associated with psychoactive substance use. Adolescents who use substances make up a large population that may benefit from applying such strategies. However, previous research in this area has focused on adults. Therefore, the purpose of this qualitative study was to describe and examine harm reduction strategies among adolescents who use psychoactive substances. Methods: Semi-structured individual interviews were conducted with 72 adolescents of equal sex distribution (aged 17-18 years) who had used various substances at least three times in the past 12 months and had no history of substance use disorders (SUD) treatment. Data were transcribed and then analyzed thematically based on the Consensual Qualitative Research approach. Findings: Adolescents who use substances described the harm reduction strategies they use. According to the meaning youth attributed to these strategies, five themes were developed, that included approaches to risk, substance use safety conditions, preparation for use, manner of use, and controlled use. Most of the identified strategies correspond to those found in studies on adults. The main source of adolescents' knowledge about these strategies was the Internet. Peers appeared to play an important role in reducing substance-related risks. Conclusions: Despite risk-taking, adolescents in our study showed active engagement in reducing their substance-related risks and harms. Practical implications are provided, including supporting harm reduction strategies, enhancing the active role of peers and the Internet as communication channels in preventing SUDs as well as other substance-related problems among adolescents.

Test-retest reliability and cross-cultural applicability of DSM-5 adopted diagnostic criteria for ketamine use disorders

BACKGROUND

Despite increasing prevalence of nonmedical ketamine use globally, data on ketamine use disorders, which are classified in the DSM-5 under criteria for phencyclidine, are limited. This study assessed the reliability and applicability of DSM-based diagnostic criteria for ketamine use disorder.

METHODS

Participants who used ecstasy were recruited through the Tri-City Study of Club Drug Use, Abuse, and Dependence in St. Louis, Miami, and Sydney. Those who reported using ketamine (lifetime use >5 times) were included in these analyses (n = 205). Participants were interviewed using the computerized Substance Abuse Module for Club Drugs (CD-SAM) at baseline and 7 days later for the reliability of diagnoses and individual diagnostic criteria.

RESULTS

Overall, 29.3% met DSM-5 adopted criteria for ketamine use disorder at Time 1. Moderate to excellent test-retest reliability was observed consistently across study sites for any ketamine use disorder (κ = 0.57, Y = 0.61) and severe ketamine use disorder (κ = 0.62, Y = 0.79). Continued use of ketamine despite knowledge of physical or psychological problems was the most frequently endorsed individual criterion (59.0%), followed by reported withdrawal (30.2%) and physically hazardous use (29.8%). All individual criteria had acceptable reliability estimates (κ ≥ 0.41).

CONCLUSIONS

Diagnoses of ketamine use disorder can be reliably evaluated using this fully structured diagnostic instrument's questions and algorithm. Ketamine-related withdrawal among people who use ketamine should be re-evaluated. Considering that after-effects of this dissociative anesthetic can last for many hours, it is important to explore a different timeframe for possible withdrawal effects.

Recreational ketamine-related deaths notified to the National Programme on Substance Abuse Deaths, England, 1997-2019

BACKGROUND

Ketamine is a phencyclidine derivative with dissociative anaesthetic properties. Increasing numbers of individuals in England take ketamine recreationally. Information on deaths arising from such use in England is presented.

METHODS

Cases were extracted on 31 January 2020 from the National Programme on Substance Abuse Deaths database, based on text searches of the cause of death, coroner's verdict and positive toxicology results for the terms 'ketamine' or 'norketamine'.

FINDINGS

During 1997-2005, there were <5 deaths p.a. in which ketamine was implicated. Numbers increased until 2009 (21), plateauing until 2016; thereafter, deaths have risen to about 30 p.a. Decedents' characteristics (N = 283): male 84.1%, mean age 31.2 (SD 10.0) years, employed 56.5%, drug use history 79.6% and living with others 60.3%. Ketamine was detected with other substances in most cases. Main (74.6%) underlying cause of death was accidental poisoning. Ketamine may have impaired judgement in other cases.

CONCLUSIONS

Although controlled, recreational ketamine use and related fatalities continue to increase. Consumers need to be more aware of the potentially fatal risks they face.

Increased Nectin-4 levels in chronic ketamine abusers and the relationship with lower urinary tract symptoms

Persistent ketamine use causes susceptibility to addiction and bladder toxicity. We examined the association of lower urinary tract symptoms and levels of Nectin-4, a member of the cell adhesion molecules that is essential for maintaining the urothelium barrier in chronic ketamine abusers. We measured the plasma levels of Nectin-4 in 88 patients with ketamine dependence and 69 controls. Patients with ketamine dependence were assessed for ketamine use variables, psychological symptoms, and lower urinary tract symptoms. We found Nectin-4 levels were increased in ketamine-dependent patients compared to the controls (p < 0.0001). Patients with urinary tract symptoms exhibited lower Nectin-4 levels than those without (p = 0.021). Our results suggest an up-regulation of Nectin-4 following chronic and heavy ketamine use. Patients with ketamine dependence with a compromised upregulation of Nectin-4 are likely to have more severe urinary tract symptoms. The mechanisms underlying the involvement of Nectin-4 in ketamine addiction and bladder toxicity warrant future investigation.

First-time offenders for recreational ketamine use under a new penalty system in Taiwan: incidence, recidivism and mortality in national cohorts from 2009 to 2017

BACKGROUND AND AIMS

Ketamine has become a new recreational drug of choice among young people in parts of Asia. Using national databases in Taiwan, this study aimed to (1) examine the yearly trend in the ketamine offence rate over time; (2) estimate the 3-year risk of drug-related re-offence and its correlates among the first-time offenders; and (3) estimate the 3-year standardized mortality ratio (SMR) among the first-time offenders.

DESIGN, SETTING AND PARTICIPANTS

Retrospective cohort studies of offenders for recreational ketamine use in a penalty system initiated in 2009. Offenders for recreational ketamine use were identified from the Administrative Penalty System for Schedule III/IV Substances database from 2009 to 2017, and the re-offence rate and mortality among first-time offenders were assessed via record-linkage within the database as well as with both the criminal drug offence database and the national mortality database. The cohort from 2009 to 2016 (n = 39 178) was used for the recidivism analysis and the cohort from 2009 to 2013 (n = 25 357) was used for the 3-year SMR analysis.

MEASUREMENTS

Recidivism was estimated using survival analysis of the event as re-arrest for using ketamine, more serious illicit drugs (Schedules I/II), or any illicit drugs (ketamine or Schedules I/II). SMRs were estimated for overall and cause-specific death within 3 years after the first offence for ketamine use.

FINDINGS

The age-standardized rates for both prevalent (1.38 per 1000) and first-time offenders (0.65 per 1000) peaked in 2013 and then decreased steadily. The 3-year risk of re-offence was 33.85% [95% confidence interval (CI) = 33.23-34.47%) for ketamine use and 39.52% (95% CI = 39.00-40.04%) for any illicit drug use. These first-time offenders had an SMR of 4.9 (95% CI = 4.3-5.4) for overall mortality, 2.1 (95% CI = 1.6-2.7) for natural deaths and 7.6 (95% CI = 6.7-8.6) for unnatural deaths.

CONCLUSIONS

Recreational ketamine use in Taiwan appears to lead not only to high risk for drug-related re-offence but also to excess mortality.

Mis-anaesthetized society: expectancies and recreational use of ketamine in Taiwan

Background

The popularity of ketamine for recreational use has been increasing in Asia, including Taiwan. Still, little known about the pattern of ketamine expectancies and whether such patterns are related to ketamine use. This study aimed to examine whether the positive and negative ketamine expectancies are differentially associated with ketamine-using behavior, and whether such relationship may differ by early-onset use of tobacco or alcohol.

Methods

Participants were recruited using respondent-driven sampling (RDS) among regular tobacco and alcohol users, aged 18 to 50, residing in Taipei from 2007 to 2010. Totally 1115 participants (with an age distribution skewed to the right, median = 26; interquartile range: 22–32) had information on substance use and completed a 12-item ketamine expectancies questionnaire (with 6 positive and 6 negative statements). Using two axes of High and Low expectancies, the four combinations of binary positive and binary negative ketamine expectancies were created. Each participant’s drug-using experience was categorized into illicit drug naïve, exclusive ketamine use, polydrug ketamine use, or other illicit drug use. Using the weights in the network output by RDS Analysis Tool, multivariable logistic regression analysis was then conducted.

Results

The weighted prevalence was 2.4% for exclusive ketamine use, 9.0% for polydrug ketamine use, and 9.1% for the other illicit drug use. Ketamine users (11.4%) had greater positive expectancies and lower negative expectancies, particularly the combination of High Positive with Low Negative, as compared to the illicit drug-naïve or other illicit drug users. After adjustment for early-onset tobacco (or alcohol) use and sociodemographic characteristics, High Positive, Low Negative, and their combination of High Positive-Low Negative expectancies remained strongly associated with ketamine uses, without evidence of moderation from early-onset use of tobacco or alcohol.

Conclusions

Positive and negative ketamine expectancies were associated in opposite directions with ketamine use, independent of early-onset use of tobacco or alcohol. Our results indicate ketamine expectancies as possible targets for future intervention and prevention of ketamine use, with a less confrontational feedback on decreasing an individual’s positive expectancies is essential in preventing young people from the initiation of ketamine use.

Harm reduction strategies related to dosing and their relation to harms among festival attendees who use multiple drugs

INTRODUCTION AND AIMS

Polysubstance users are a high-risk population for negative health-related consequences. Although some studies have described harm reduction strategies adopted by polysubstance users, studies have not examined their effectiveness in minimising health-related consequences. We aimed to identify dosing-related harm reduction strategies in a sample of polysubstance-using dance festival attendees, and explore the relationship between harm reduction strategies and self-reported adverse health consequences.

DESIGN AND METHODS

Data were examined for 1226 past-year dance festival attendees who self-identified as past-year multiple drug users. We conducted bivariable and multivariable analyses to explore relationships between six dosing-related harm reduction strategies and 13 self-reported adverse consequences.

RESULTS

Self-reported use of dosing-related harm reduction strategies was prevalent, mainly avoidance of mixing depressants (69.2%) and setting limits on quantity (62.2%). Frequent users of harm reduction strategies reported experiencing fewer adverse health consequences (P values < 0.05). Those who reportedly set limits on quantity were at decreased odds of experiencing a bad mood after drug use, sexual difficulties while under drug influence, injuries or fractures while under drug influence, and involvement in fights or being attacked while under drug influence (P values < 0.05). Moreover, those who report frequently avoid mixing depressants were at decreased odds of experiencing headache, loss of consciousness, drop in blood pressure, injuries of fractures, and fights or attacks (P values < 0.05).

DISCUSSION AND CONCLUSIONS

Adoption of dosing-related harm reduction strategies appears to be associated with less drug-related harm among polysubstance-using festival attendees. Findings may inform organisations and policymakers in the designing of harm reduction interventions with this population.

Polysubstance use profiles among electronic dance music party attendees in New York City and their relation to use of new psychoactive substances

BACKGROUND

Electronic Dance Music (EDM) party attendees are often polysubstance users and are at high risk for use of new psychoactive substances (NPS). We sought to identify patterns of use of common illegal drugs among EDM party attendees, sociodemographic correlates, and use of NPS as a function of patterns of use of more common drugs to inform prevention and harm reduction.

METHOD

Using time-space-sampling, 1045 individuals aged 18-40 were surveyed entering EDM parties in New York City. We queried past-year use of common illegal drugs and 98 NPS. We conducted latent class analysis to identify polysubstance use profiles of use of eight common drugs (i.e., ecstasy, ketamine, LSD, mushrooms, powder cocaine, marijuana, amphetamine, benzodiazepines). Relationships between drug classification membership and sociodemographics and use of drugs within six NPS categories were examined.

RESULTS

We identified four profiles of use of common drugs: non-polysubstance use (61.1%), extensive polysubstance use (19.2%), moderate polysubstance use/stimulants (12.8%), and moderate polysubstance use/psychedelics (6.7%). Those in the moderate/psychedelic group were at higher odds of using NPS with psychedelic-type effects (2C, tryptamines, and other "new" psychedelics; Ps<0.05). Extensive polysubstance users were at increased odds of reporting use of 2C drugs, synthetic cathinones ("bath salts"), tryptamines, other new (non-phenethylamine) psychedelics, new dissociatives, and synthetic cannabinoids (Ps<0.05).

CONCLUSION

NPS preference is linked to the profile of use of common drugs among individuals in the EDM scene. Most participants were identified as non-polysubstance users, but findings may help inform preventive and harm reduction interventions among those at risk in this scene.

Decreased Blood Levels of Oxytocin in Ketamine-Dependent Patients During Early Abstinence

Background: Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is a common drug of abuse worldwide. Existing evidence suggest a disruption of oxytocin system involves in the development of addiction. In this study, we aimed to investigate the role of oxytocin in ketamine addiction by measuring the blood oxytocin levels in ketamine-dependent (KD) patients. Methods: Sixty-five KD patients and 65 controls were enrolled. Fasting plasma levels of oxytocin were determined at baseline and 1 and 2 weeks after ketamine withdrawal. Ketamine use variables, Beck Depression Inventory, Beck Anxiety Inventory (BAI), Visual Analog Scale for craving, and Childhood Trauma Questionnaire-short form were assessed in KD patients. Results: KD patients had significantly lower levels of oxytocin at baseline compared to controls (5.89 ± 2.13 vs. 9.53 ± 4.17 ng/mL, P < 0.001). Oxytocin levels increased after one (6.74 ± 2.63, P < 0.002) and 2 weeks (6.89 ± 2.69, P = 0.01) of withdrawal in KD patient despite the levels were still lower than controls (P = 0.001 and 0.002, respectively). The clinical variables did not correlate with baseline oxytocin levels except BAI scores, which showed a negative correlation with the levels (r = -0.263; P = 0.039). Conclusion: We found a distinctively reduced oxytocin level in KD patients and the level did not normalize after early abstinence. Lower oxytocin might be associated with anxious phenotype of ketamine dependence. These results suggest that oxytocin system dysregulated following chronic ketamine abuse and might provide insight in evaluating the potential therapeutic use of oxytocin for treating ketamine dependence.