The burden and management of crystal meth use

The Neurobiology of Methamphetamine Addiction and the Potential to Reduce Misuse Through Conjugate Vaccines Targeting Toll-Like Receptor 4

The methamphetamine epidemic continues to worsen each year and has contributed to more overdose deaths than opioids. Methamphetamine was listed in the top ten lethal drugs in 2021 in the United States. The drug has been shown to cause health problems such as addiction and neurological and behavioral changes. One possible solution to address this crisis is through vaccinations. Vaccinations consist of injecting a controlled substance with the goal of creating compound-specific antibodies. Although still early in development, vaccinations have been found to improve withdrawal symptoms and decrease drug-seeking behavior with minimal health side effects in rodent studies. This paper provides an overview of the clinical presentation and neurobiology of methamphetamine addiction and drug-seeking behaviors. The responses and adverse effects of conjugate vaccines IXTv-100 with adjuvant glucopyranosyl lipid A administered in oil-water stable emulsion and tetanus-toxoid conjugated to succinyl-methamphetamine adsorbed on aluminum hydroxide combined with adjuvant E6020 are examined.

PPARγ/Adiponectin axis attenuates methamphetamine-induced conditional place preference via the hippocampal AdipoR1 signaling pathway

Methamphetamine (METH) is a highly addictive psychostimulant. The adipocyte-derived hormone adiponectin has a broad spectrum of functions in the brain. However, limited research has been conducted on the effect of adiponectin signaling on METH-induced conditioned place preference (CPP) and knowledge of the underlying neural mechanisms is scarce. The METH induced adult male C57/BL6J mice model were used for testing the therapeutic activities of intraperitoneal injection of AdipoRon or Rosiglitazone, and AdipoR1 overexpression in hippocampal dentate gyrus (DG), and chemogenetic inhibiting the neural activity of DG, and the changes of neurotrophic factors, synaptic molecules, and glutamate receptors, and inflammatory cytokines were also measured. We found that adiponectin expression was significantly reduced in METH addicted patients and mice. Our findings also showed that injection of AdipoRon or Rosiglitazone alleviated the METH-induced CPP behavior. Moreover, the expression of AdipoR1 in the hippocampus was also reduced, and AdipoR1 overexpression blocked the development of METH-induced CPP behavior through regulatory effects on neurotrophic factors, synaptic molecules, and glutamate receptors. The observed inhibitory neural activity of the hippocampal dentate gyrus (DG) induced via a chemogenetic approach produced a therapeutic effect on the METH-induced CPP behavior. Finally, we identified an abnormal expression of some key inflammatory cytokines through the PPARγ/Adiponectin/AdipoR1 axis. This study demonstrates that adiponectin signaling is a promising diagnostic and therapeutic target for METH addiction.

Imaging oxidative stress in brains of chronic methamphetamine users: A combined 1H-magnetic resonance spectroscopy and peripheral blood biomarker study

Introduction

Preclinical data suggest methamphetamine (MA), a widely used stimulant drug, can harm the brain by causing oxidative stress and inflammation, but only limited information is available in humans. We tested the hypothesis that levels of glutathione (GSH), a major antioxidant, would be lower in the brains of chronic human MA preferring polysubstance users. We also explored if concentrations of peripheral immunoinflammatory blood biomarkers were related with brain GSH concentrations.

Methods

20 healthy controls (HC) (33 years; 11 M) and 14 MA users (40 years; 9 M) completed a magnetic resonance spectroscopy (MRS) scan, with GSH spectra obtained by the interleaved J-difference editing MEGA-PRESS method in anterior cingulate cortex (ACC) and left dorsolateral prefrontal cortex (DLPFC). Peripheral blood samples were drawn for measurements of immunoinflammatory biomarkers. Independent samples t-tests evaluated MA vs. HC differences in GSH.

Results

GSH levels did not differ between HC and MA users (ACC p = 0.30; DLPFC p = 0.85). A total of 17 of 25 immunoinflammatory biomarkers were significantly elevated in MA users and matrix metalloproteinase (MMP)-2 (r = 0.577, p = 0.039), myeloperoxidase (MPO) (r = -0.556, p = 0.049), and MMP-9 (r = 0.660, p = 0.038) were correlated with brain levels of GSH.

Conclusion

Normal brain GSH in living brain of chronic MA users is consistent with our previous postmortem brain finding and suggests that any oxidative stress caused by MA, at the doses used by our participants, might not be sufficient to cause either a compensatory increase in, or substantial overutilization of, this antioxidant. Additionally, more research is required to understand how oxidative stress and inflammatory processes are related and potentially dysregulated in MA use.

Substance use in the emergency department: Screening for risky drug use, using the ASSIST-Lite

INTRODUCTION

Substance use is a common contributing factor to emergency department (ED) presentations. While screening, brief intervention, and referral to treatment for alcohol and tobacco is common in ED settings, it is not routinely conducted for illicit substances. This study aimed to deploy the ASSIST-Lite to screen for risky use of alcohol and other drugs in the ED, to identify differences in risk based on between demographic characteristics.

METHOD

All ED attenders, aged 18 years or older, deemed well enough to participate were approached. Recruitment occurred at the Royal Adelaide Hospital ED between May and June 2017. Participants were asked to self-complete the ASSIST-Lite in the ED waiting room. Overall, 632 people were approached, of which 479 (75.8%) agreed to participate.

RESULTS

Alcohol (72.2%), tobacco (27.1%) and cannabis (15.2%) were most commonly reported. Eighty-nine participants reported moderate- or high-risk use of two substances, and a further 49 individuals reported moderate- or high-risk use of three or more substances. Across most substances, age, gender and employment status was associated with risky substance use, with higher likelihood of risk reported by males, unemployed and younger participants. Unemployment was also significantly associated with increased risk severity for both moderate and high-risk illicit use.

DISCUSSIONS AND CONCLUSIONS

The rate of risky illicit and polysubstance use found here highlight the need more focused research in ED settings. The findings also provide support for more routine screening, and early intervention approaches; and suggest the need for active referral pathways through an alcohol and other drug consultation liaison service.

Characterising methamphetamine use to inform health and social policies in Manitoba, Canada: a protocol for a retrospective cohort study using linked administrative data

INTRODUCTION

Rising use of methamphetamine is causing significant public health concern in Canada. The biological and behavioural effects of methamphetamine range from wakefulness, vigour and euphoria to adverse physical health outcomes like myocardial infarction, haemorrhagic stroke, arrhythmia and seizure. It can also cause severe psychological complications such as psychosis. National survey data point to increasing rates of methamphetamine use, as well as increasing ease of access and serious methamphetamine-related harms. There is an urgent need for evidence to address knowledge gaps, provide direction to harm reduction and treatment efforts and inform health and social policies for people using methamphetamine. This protocol describes a study that aims to address this need for evidence.

METHODS

The study will use linked, whole population, de-identified administrative data from the Manitoba Population Research Data Repository. The cohort will include individuals in the city of Winnipeg, Manitoba, who came into contact with the health system for reasons related to methamphetamine use from 2013 to 2021 and a comparison group matched on age, sex and geography. We will describe the cohort's sociodemographic characteristics, calculate incidence and prevalence of mental disorders associated with methamphetamine use and examine rates of health and social service use. We will evaluate the use of olanzapine pharmacotherapy in reducing adverse emergency department outcomes. In partnership with Indigenous co-investigators, outcomes will be stratified by First Nations and Métis identity.

ETHICS AND DISSEMINATION

The study was approved by the University of Manitoba Health Research Ethics Board, and access datasets have been granted by all data providers. We also received approval from the First Nations Health and Social Secretariat of Manitoba's Health Information Research Governance Committee and the Manitoba Métis Federation. Dissemination will be guided by an 'Evidence 2 Action' group of public rightsholders, service providers and knowledge users who will ensure that the analyses address the critical issues.

Neurotoxicity of methamphetamine: Main effects and mechanisms

Methamphetamine (METH) is an illicit psychostimulant that is abused throughout the world. METH addiction is also a major public health concern and the abuse of large doses of the drug is often associated with serious neuropsychiatric consequences that may include agitation, anxiety, hallucinations, paranoia, and psychosis. Some human methamphetamine users can also suffer from attention, memory, and executive deficits. METH-associated neurological and psychiatric complications might be related, in part, to METH-induced neurotoxic effects. Those include altered dopaminergic and serotonergic functions, neuronal apoptosis, astrocytosis, and microgliosis. Here we have endeavored to discuss some of the main effects of the drug and have presented the evidence supporting certain of the molecular and cellular bases of METH neurotoxicity. The accumulated evidence suggests the involvement of transcription factors, activation of dealth pathways that emanate from mitochondria and endoplasmic reticulum (ER), and a role for neuroinflammatory mechanisms. Understanding the molecular processes involved in METH induced neurotoxicity should help in developing better therapeutic approaches that might also serve to attenuate or block the biological consequences of use of large doses of the drug by some humans who meet criteria for METH use disorder.

Associations between eating disorders and illicit drug use among college students

OBJECTIVE

To estimate the associations between a positive eating disorder screen and any lifetime eating disorder diagnosis and illicit drug use among a large, diverse sample of college students.

METHOD

We analyzed data from the national (United States), cross-sectional 2018-2019 Healthy Minds Study (HMS; n = 42,618; response rate: 16%). HMS collects information on the physical, mental, and social health of college students. Multiple logistic regression analyses were used to estimate the association between a positive eating disorder screen (measured using the SCOFF) and any self-reported lifetime eating disorder diagnosis and self-reported illicit drug use in the past 30 days (any illicit drug use and use of marijuana, cocaine, heroin, methamphetamines, stimulants, ecstasy, opioids, benzodiazepines), while adjusting for potential confounders.

RESULTS

Among the sample, 54.34% (n = 28,608) were female and the mean age of participants was 23.30 (SE ± 0.05) years. Logistic regression analyses revealed unique associations between a positive eating disorder screen and any lifetime eating disorder diagnosis and illicit drug use among the sample of college student participants. A positive eating disorder screen was most strongly associated with methamphetamine use (adjusted odds ratio [AOR] 3.93, 95% confidence interval [CI] 1.43-10.78), and any lifetime eating disorder diagnosis was most strongly associated with benzodiazepine use (AOR 3.42, 95% CI 2.28-5.13).

DISCUSSION

Illicit drug use is common among college students who screen positive for an eating disorder and report any lifetime eating disorder diagnosis. The co-occurring nature of eating disorders and illicit drug use may complicate treatment and lead to compounded adverse health outcomes.

Crystal methamphetamine use in British Columbia, Canada: A cross-sectional study of people who access harm reduction services

INTRODUCTION

Increased use of crystal methamphetamine ("crystal meth") has been observed across North America and international jurisdictions, including a notable increase in the presence of methamphetamines in illicit drug toxicity deaths in British Columbia (BC), Canada. We used data from a cross-sectional survey and urine toxicology screening to report the prevalence, correlates, and validity of self-reported crystal meth use among clients of harm reduction sites in BC.

MATERIALS AND METHODS

Survey data were collected from 1,107 participants across 25 communities in BC, through the 2018 and 2019 Harm Reduction Client Survey. We described reported substance use and used a multivariate logistic regression model to characterize crystal meth use. Urine samples provided by a subset of participants were used to derive validity of self-reported three-day crystal meth use compared to urine toxicology screening.

RESULTS

Excluding tobacco, crystal meth was the most frequently reported substance used in the past three days in 2018 and 2019 (59.7% and 71.7%, respectively). Smoking was the dominant route of administration for crystal meth, crack, heroin, and fentanyl. Multivariate analysis determined significantly higher odds of crystal meth use among those who used opioids (Adjusted Odds Ratio [AOR] = 3.13), cannabis (AOR = 2.10), and alcohol (1.41), and among those who were not regularly housed (AOR = 2.08) and unemployed (AOR = 1.75). Age ≥50 was inversely associated with crystal meth use (AOR = 0.63). Sensitivity of self-reported crystal meth use was 86%, specificity was 86%, positive predictive value was 96%, and negative predictive value was 65%.

CONCLUSIONS

Crystal meth was the most commonly used substance among clients of harm reduction sites in BC in 2018 and 2019, and was frequently used concurrently with opioids. Comparison to urine samples demonstrated high validity of self-reported crystal meth use. Understanding evolving patterns of substance use will be imperative in tailoring harm reduction and substance use services for individuals that use crystal meth.

Increasing age and methamphetamine use

ANALYSIS

of autopsy files at Forensic Science SA was undertaken over a 20-year period (2000-2019) in five representative time periods to determine the average ages for all adults (≥18 years) where methamphetamine was detected. There were 239 cases with statistically significant increased mean ages over the time of the study ranging from 32.6yrs in 2000 to 42.2yrs in 2019 (p < 0.0001). Although methamphetamine use may be considered predominantly a feature of younger individuals this does not appear to be the case. Whether this apparent increase in the age of methamphetamine users was due to natural aging of methamphetamine users, an increase in use of methamphetamine by older individuals, or to an increased capture of older cases due to wider toxicological screening is uncertain. However, the importance of these results is to alert practitioners to the presence of methamphetamine use in older individuals which may predispose to death given the increased incidence of underlying cardiovascular diseases with age. In addition, in clinical settings there exists a cohort of older individuals who may be at risk of exacerbating their heart disease and precipitating cardiac events by using methamphetamine.

Toxic Effects of Methamphetamine on Perivascular Health: Co-morbid Effects of Stress and Alcohol Use Disorders

Methamphetamine (Meth) abuse presents a global problem and commonly occurs with stress and/or alcohol use disorders. Regardless, the biological causes and consequences of these comorbidities are unclear. Whereas the mechanisms of Meth, stress, and alcohol abuse have been examined individually and well-characterized, these processes overlap significantly and can impact the neural and peripheral consequences of Meth. This review focuses on the deleterious cardio- and cerebrovascular effects of Meth, stress, alcohol abuse, and their comorbid effects on the brain and periphery. Points of emphasis are on the composition of the blood-brain barrier and their effects on the heart and vasculature. The autonomic nervous system, inflammation, and oxidative stress are specifically highlighted as common mediators of the toxic consequences to vascular and perivascular health. A significant portion of the Meth abusing population also presents with stress and alcohol use disorders, prompting a need to understand the mechanisms underlying their comorbidities. Little is known about their possible convergent effects. Therefore, the purpose of this critical review is to identify shared mechanisms of Meth, chronic stress, and alcohol abuse that contributes to the dysfunction of vascular health and underscores the need for studies that directly address their interactions.

Association Between Alexithymia, Social Support, and Duration of Methamphetamine Use Among Male Methamphetamine-Dependent Patients

Introduction: China has 1.18 million methamphetamine abusers. Among the illegal drugs in China, methamphetamine has the highest abuse rate. Although previous studies have indicated a positive relationship between alexithymia and declining social support, the incidence of alexithymia, the total duration of methamphetamine dependence, social support, and the relationships between them among methamphetamine-dependent patients in the Chinese population have been rarely reported. Methods: A total of 113 methamphetamine-dependent patients (all male, mean age 30.45 ± 3.81 years) were enrolled in this cross-sectional study. General demographic data were collected. Alexithymia and social support were measured by Toronto Alexithymia Scale and Social Support Rating Scale. Results: Duration of methamphetamine use among Chinese male methamphetamine-dependent patients in compulsory detoxification was 8.01 ± 3.80 years on average, 23% (26/113) methamphetamine-dependent patients were considered to have alexithymia personality traits. Compared with short-duration methamphetamine-dependent patients (≤8 years), long-duration methamphetamine-dependent patients (> 8 years) were characterized by older age, higher incidence of alexithymia, less subjective social support and support availability, and greater difficulty in identifying feelings. The results of correlation analysis and multiple linear regression analysis indicated that the total duration of methamphetamine use was positively correlated with difficulty in identifying feelings, but negatively correlated with subjective social support. Conclusions: This study provides support for an association between the duration of methamphetamine use and difficulty in identifying feelings or subjective social support. Although the causality is still unclear, this finding should be considered in the psychotherapy of methamphetamine rehabilitation.

The association between interleukin-8 levels and the development of withdrawal symptoms during methamphetamine abstinence

OBJECTIVE

Withdrawal symptoms are common during methamphetamine (METH) abstinence. This study aimed to explore the association between serum interleukins and withdrawal symptoms during METH abstinence.

METHODS

This study recruited 120 METH users, and 94 of them completed the 2-week follow-up. Serum interleukin-1β, 6,8,10 were tested at admission. Withdrawal symptoms were assessed by the Methamphetamine Withdrawal Questionnaire (MAWQ).

RESULTS

Serum IL-8 levels were positively correlated with MAWQ scores at the 2-week endpoint (r = .257, p = .013). The variation of the MAWQ scores during the 2-week follow-up was negatively correlated with serum IL-8 levels at admission (r = -.249, p = .026). Serum IL-8 levels remained associated with the severity of METH withdrawal symptoms (β = .363, p = .023), after adjusting for potential confounders.

LIMITATIONS

This study did not include normal controls. Most patients were male and cigarette smokers. Patients were only followed up for 2 weeks, and their toxicology data were not collected. Interleukins were only measured at admission, and were tested in serum, not in the cerebrospinal fluid.

CONCLUSIONS

Our study demonstrated that higher serum IL-8 levels may predict more severe withdrawal symptoms at 2 weeks after METH abstinence.

Intestinal ischemia due to methamphetamine use: A case report

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Methamphetamine is associated with non-occlusive intestinal ischemia.

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Splanchnic vasocontriction of mesenteric and colonic vessels is the most likely cause of methamphetamine-induced intestinal ischemia.

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Surgeons should have a high index of suspicion for intestinal ischemia in methamphetamine users who present with acute abdominal pain.

Introduction

Methamphetamine use is a rare cause of intestinal ischemia but is of clinical significance due to its high morbidity and mortality. Knowledge of methamphetamine-induced intestinal ischemia has been limited to few case reports.

Case presentation

We describe the case of a 48-year-old man who presented with ischemic bowel related to methamphetamine use. With concern for intestinal infarction the patient was taken to the operating room for emergency laparotomy, which found a segmental gangrene of small bowel and colon. The patient subsequently underwent right hemicolectomy and small bowel resection for damage control, followed by second-look laparotomy and anastomosis. The patient recovered well from the surgery and was discharged without complications.

Conclusion

This case report alerts surgeons to have a high index of suspicion for intestinal ischemia in methamphetamine users who present with acute abdominal pain.

Improving Rehabilitative Care of Methamphetamine Users in Germany: The Expert's Perspective

Methamphetamine is one of the most frequently used drugs worldwide. In Germany, methamphetamine use has greatly increased in recent years, presenting the rehabilitative treatment system with new challenges. In this study, we identified deficits and possibilities for optimization in the field of medical rehabilitation. A total of 39 interviews and two focus groups with experts along the treatment course of methamphetamine users were conducted. Our analyses indicate that methamphetamine users are more difficult to treat compared with patients who consume other drugs. They are more likely to be associated with problematic characteristics and behaviors than other rehabilitants. Several health care deficits were revealed: too short rehabilitation treatment, no specific or differentiated therapy concepts, lack of capacity for education and vocational training, lack of outpatient options, and insufficient facilities for parents and children. Findings indicate that inadequate rehabilitation is being provided for methamphetamine users in Germany, indicating a need to adapt treatment for this group.

Association between serum malondialdehyde levels and depression during early methamphetamine withdrawal

Some evidence suggested that malondialdehyde (MDA) as a marker of oxidative stress played an important part in modulating the activities of depression. Methamphetamine (METH) dependence often lead to depression that may associate with MDA. In this study, our purpose was to explore the association between serum MDA levels and depression during METH withdrawal. 179 METH-dependent patients were recruited in this study and 144 (80.4%) finished the assessment. We measured serum MDA at 532 nm spectrophotometrically at admission. The short form of the Beck Depression Inventory (BDI-13) was used to evaluate depression symptoms. Patients were identified to have depression symptoms with the BDI score ≥ 8. As a result, 89 (61.8%) of the remaining 144 METH-dependent patients were identified to have depression symptoms. Patients with depression symptoms showed significantly higher serum MDA levels than non-depression patients (3.42 ± 1.60 nmol/ml vs. 2.43 ± 1.25 nmol/ml; p <  0.001). After controlling for potential confounding variables in our logistic model, serum MDA levels were independently associated with the development of depression during early METH withdrawal (OR =1.952, 95% CI, 1.414-2.694, p < 0.001). Furthermore, our study found a positive association between Beck Depression Inventor (BDI) score in early METH abstinence and serum MDA levels (r =0.185; p =  0.026). Our results indicated that higher serum MDA levels were related to higher risk of depression symptoms during early METH withdrawal.

DARK Classics in Chemical Neuroscience: Methamphetamine

Methamphetamine has the second highest prevalence of drug abuse after cannabis, with estimates of 35 million users worldwide. The ( S)-(+)-enantiomer is the illicit drug, active neurostimulant, and eutomer, while the ( R)-(-)-enantiomer is contained in over the counter decongestants. While designated a schedule II drug in 1970, ( S)-(+)-methamphetamine is available by prescription for the treatment of attention-deficit disorder and obesity. The illicit use of ( S)-(+)-methamphetamine results in the sudden "rush" of stimulation to the motivation, movement, pleasure, and reward centers in the brain, caused by rapid release of dopamine. In this review, we will provide an overview of the synthesis, pharmacology, adverse effects, and drug metabolism of this widely abused psychostimulant that distinguish it as a DARK classic in Chemical Neuroscience.

Managing the Patient With Pulmonary Arterial Hypertension and Methamphetamine Use: A Practical Perspective for the Clinician

Pulmonary arterial hypertension (PAH) is a serious, chronic, progressive cardiopulmonary disease. PAH is associated with several concomitant conditions, as well as drugs and toxins.12 Methamphetamine abuse is likely associated with the development of PAH.3 Methamphetamine abuse is epidemic in the United States and abroad, with rates of new users escalating since 2012. There are over 100,000 new users annually as young as 12 years old. Treating a patient with a history of methamphetamine abuse poses many challenges for a clinician, including nonadherence, therapeutic treatment selection, complex psychosocial issues, and relapse or continued drug abuse. Patients with methamphetamine-associated PAH (Meth-APAH) have higher mortality rates when compared to idiopathic PAH.3 Having a better understanding of the complexities of addiction and working with a multidisciplinary team that includes a social worker to provide care and counseling to these patients can improve their trajectory. In this article, we will offer insight and background into methamphetamine abuse and addiction, as well as discuss a practical approach for clinicians in treating a patient with Meth-APAH, based on the literature, as well as our personal experiences at University of California, San Francisco Medical Center.

Efficacy and safety of psychostimulants for amphetamine and methamphetamine use disorders: a systematic review and meta-analysis

BACKGROUND

Amphetamine and methamphetamine use disorders are associated with severe health and social consequences. No pharmacological therapy has been approved for the treatment of these disorders. Psychostimulants can act as maintenance-like therapies for managing substance use among these patients. The aim of this study is to evaluate the literature examining the efficacy and safety of psychostimulant agents for increasing abstinence and treatment retention among patients with amphetamine and methamphetamine use disorders.

METHODS

We searched MEDLINE, EMBASE, PsycInfo, Cochrane Central, and CINAHL from inception to August 2016. Selection of studies, data extraction, and risk of bias assessment were conducted independently by two reviewers. We conducted meta-analyses to provide a pooled summary estimate for included trials and report the review according to PRISMA guidelines.

RESULTS

We identified and selected 17 studies with 1387 participants. Outcome reporting across trials was inconsistent, and the overall quality of evidence was very low due to high risk of bias and indirectness. A meta-analysis of five trials (642 participants) found no effect of psychostimulants for end-of-study abstinence (odds ratio = 0.97, 95% confidence interval 0.65 to 1.45). Additionally, the pooled estimate from 14 studies (1184 participants) showed no effect of psychostimulants for treatment retention (odds ratio = 1.20, 95% confidence interval = 0.91 to 1.58). The incidence of serious adverse events did not differ between intervention and placebo groups based on qualitative reports from trials.

CONCLUSIONS

Quantitative analyses showed no effect of psychostimulants for sustained abstinence or treatment retention. We also identified the need for more rigorous studies in this research area with clinician and patient important outcomes.

Methamphetamine use in Central Germany: protocol for a qualitative study exploring requirements and challenges in healthcare from the professionals' perspective

INTRODUCTION

The synthetic drug methamphetamine with its high addiction potential is associated with substantial adverse health effects. In Germany, especially Central Germany, the increase in the consumption of methamphetamine has exceeded that of other illegal drugs. The treatment system and service providers are facing new challenges due to this rise in consumption. This qualitative study will explore the demand created by the increasing healthcare needs of methamphetamine-addicted persons in Central Germany, and the difficulty of rehabilitating addicted people.

METHODS AND ANALYSIS

The collection of empirical data will take place in a consecutive, two-stage process. In the first part of data collection, the experiences and perspectives of 40 professionals from numerous healthcare sectors for methamphetamine-addicted persons will be explored with the help of semistructured face-to-face interviews and probed by the research team. These findings will be discussed in 2 focus groups consisting of the participants of the face-to-face interviews; these group discussions comprise the second part of the data collection process. The interviews will be audio recorded, transcribed, and then subjected to qualitative content analysis.

ETHICS AND DISSEMINATION

All interviewees will receive comprehensive written information about the study, and sign a declaration of consent prior to the interview. The study will comply rigorously with data protection legislation. The research team has obtained the approval of the Ethical Review Committee at the Martin Luther University Halle-Wittenberg, Germany. The results of the study will be published in high-quality, peer-reviewed international journals, presented at several congresses and used to design follow-up research projects.

TRIAL REGISTRATION NUMBER

VfD_METH_MD_15_003600.

High Prevalence of Assisted Injection Among Street-Involved Youth in a Canadian Setting

Many people who inject illicit drugs receive manual assistance when injecting, and this practice has been linked to increased risk of HIV infection and other harms. Little is known, however, about this practice among youth. This study uses a multivariate generalized estimating equation to identify factors associated with receiving assistance with injecting among a cohort of street-involved youth aged 14-26 in Vancouver, Canada. A total of 253 participants reported injecting drugs during the study period, and 49 % (n = 125) of these youth reported receiving assistance with injecting in the past 6 months. In multivariate analysis, younger age, female gender, binge drug use, heroin injecting, cocaine injecting, crystal methamphetamine injecting, and syringe sharing were positively and independently associated with assisted injection (all p < 0.05). These findings underscore the need for expanding substance abuse treatment alongside HIV prevention and health promotion interventions to empower youth to enact safer injection practices.

Altered Statistical Learning and Decision-Making in Methamphetamine Dependence: Evidence from a Two-Armed Bandit Task

Understanding how humans weigh long-term and short-term goals is important for both basic cognitive science and clinical neuroscience, as substance users need to balance the appeal of an immediate high vs. the long-term goal of sobriety. We use a computational model to identify learning and decision-making abnormalities in methamphetamine-dependent individuals (MDI, n = 16) vs. healthy control subjects (HCS, n = 16), in a two-armed bandit task. In this task, subjects repeatedly choose between two arms with fixed but unknown reward rates. Each choice not only yields potential immediate reward but also information useful for long-term reward accumulation, thus pitting exploration against exploitation. We formalize the task as comprising a learning component, the updating of estimated reward rates based on ongoing observations, and a decision-making component, the choice among options based on current beliefs and uncertainties about reward rates. We model the learning component as iterative Bayesian inference (the Dynamic Belief Model), and the decision component using five competing decision policies: Win-stay/Lose-shift (WSLS), ε-Greedy, τ-Switch, Softmax, Knowledge Gradient. HCS and MDI significantly differ in how they learn about reward rates and use them to make decisions. HCS learn from past observations but weigh recent data more, and their decision policy is best fit as Softmax. MDI are more likely to follow the simple learning-independent policy of WSLS, and among MDI best fit by Softmax, they have more pessimistic prior beliefs about reward rates and are less likely to choose the option estimated to be most rewarding. Neurally, MDI's tendency to avoid the most rewarding option is associated with a lower gray matter volume of the thalamic dorsal lateral nucleus. More broadly, our work illustrates the ability of our computational framework to help reveal subtle learning and decision-making abnormalities in substance use.

Acute exposure to methamphetamine alters TLR9-mediated cytokine expression in human macrophage

Recent studies show that methamphetamine (Meth) use leads to higher susceptibility to and progression of infections, which suggests impairment of the immune system. The first line of defense against infections is the innate immune system and the macrophage is a key player in preventing and fighting infections. So we profiled cytokines over time in Meth treated THP-1 cells, as a human macrophage model, at a relevant concentration using high throughput screening to find a signaling target. We showed that after a single exposure, the effect of Meth on macrophage cytokine production was rapid and time dependent and shifted the balance of expression of cytokines to pro-inflammatory. Our results were analogous to previous reports in that Meth up-regulates TNF-α and IL-8 after two hours of exposure. However, global screening led to the novel identification of CXCL16, CXCL1 and many other up-regulated cytokines. We also showed CCL7 as the most down-regulated chemokine due to Meth exposure, which led us to hypothesize that Meth dysregulates the MyD88-dependent Toll-like receptor 9 (TLR9) signaling pathway. In conclusion, altered cytokine expression in macrophages suggests it could lead to a suppressed innate immunity in people who use Meth.

Illicit drug use and harms, and related interventions and policy in Canada: A narrative review of select key indicators and developments since 2000

BACKGROUND

By the year 2000, Canada faced high levels of illicit drug use and related harms. Simultaneously, a fundamental tension had raisen between continuing a mainly repression-based versus shifting to a more health-oriented drug policy approach. Despite a wealth of new data and numerous individual studies that have emerged since then, no comprehensive review of key indicators and developments of illicit drug use/harm epidemiology, interventions and law/policy exist; this paper seeks to fill this gap.

METHODS

We searched and reviewed journal publications, as well as key reports, government publications, surveys, etc. reporting on data and information since 2000. Relevant data were selected and extracted for review inclusion, and subsequently grouped and narratively summarized in major topical sub-theme categories.

RESULTS

Cannabis use has remained the principal form of illicit drug use; prescription opioid misuse has arisen as a new and extensive phenomenon. While new drug-related blood-borne-virus transmissions declined, overdose deaths increased in recent years. Acceptance and proliferation of - mainly local/community-based - health measures (e.g., needle exchange, crack paraphernalia or naloxone distribution) aiming at high-risk drug users has evolved, though reach and access limitations have persisted; Vancouver's 'supervised injection site' has attracted continued attention yet remains un-replicated elsewhere in Canada. While opioid maintenance treatment utilization increased, access to treatment for key (e.g., infectious disease, psychiatric) co-morbidities among drug users remained limited. Law enforcement continued to principally focus on cannabis and specifically cannabis users. 'Drug treatment courts' were introduced but have shown limited effectiveness; several attempts cannabis control law reform have failed, except for the recent establishment of 'medical cannabis' access provisions.

CONCLUSIONS

While recent federal governments introduced several law and policy measures reinforcing a repression approach to illicit drug use, lower-level jurisdictions (e.g., provincial/municipal levels) and non-governmental organizations increasingly promoted social- and health-oriented intervention frameworks and interventions, therefore creating an increasingly bifurcated - and inherently contradictory - drug policy landscape and reality in Canada.

Prevalence and correlates of depressive symptoms during early methamphetamine withdrawal in Han Chinese population

BACKGROUND

Depression, a common comorbidity of drug abuse, is often a core component of withdrawal symptoms; however, risk factors associated with depressive symptoms during the acute stage of withdrawal among methamphetamine (METH) users are not well understood. This study investigated the correlations between several potential risk factors and depressive symptoms during acute METH withdrawal in a Han Chinese population.

METHODS

A total of 243 eligible Chinese METH users were recruited from Wenzhou Sanyang Detoxification Institute in Zhejiang province from November 2012 to June 2013. A set of self-administrative questionnaires were used to collect information about socio-demographics, drug use history and depression. Thirteen-item Beck Depression Inventory (BDI-13) was used to measure depressive symptoms.

RESULTS

METH users had a mean BDI-13 score of 12.39; 157 subjects (64.6%) reported depressive symptoms during METH withdrawal, of which 74 subjects (30.5%) reported moderate depressive symptoms and 83 subjects (34.1%) reported severe depressive symptoms. Higher frequency of drug use and history of METH-use relapse were associated with depressive symptoms (adjusted OR=2.8; 95% CI=1.56-5.04) and (adjusted OR=3.4; 95% CI=1.36-8.49), respectively. Moderate alcohol drinking was associated with less risk for depressive symptoms during acute withdrawal (adjusted OR=0.54; 95% CI=0.31-0.93).

CONCLUSIONS

Depressive symptoms are common during early METH withdrawal. In addition, several risk factors including frequency of METH use and history of relapse were positively associated with depressive symptoms during that period while moderate alcohol drinking was negatively associated with depressive symptoms.

Serum brain-derived neurotrophic factor levels were reduced during methamphetamine early withdrawal

Methamphetamine (METH) abuse is an increasing public health problem worldwide. Many of the METH-induced physical and mental problems are associated with the neurotoxic effects of METH. Animal studies have shown that brain-derived neurotrophic factor (BDNF) decreased after repeated amphetamine administration and increased at 30 and 90 days from psychostimulant withdrawal, suggesting that there might be a psychostimulant-induced neuroprotective dysfunction followed by a neuroadaptive process in the brain. However, current research on the role of BDNF in human METH addiction is limited, particularly during early withdrawal. The aim of this study was to assess the serum BDNF levels in METH abusers during the early withdrawal stage. Two groups of subjects were enrolled: (1) 59 DSM-IV METH abusers confirmed by board-certified psychiatrists during the first 3 weeks of withdrawal; (2) 59 age- and sex-matched healthy controls. We found that serum BDNF levels were significantly and constantly lower in the METH abusers during early withdrawal than those of the healthy controls. This indicates that METH abusers might have severe BDNF dysfunction and an impaired neuroprotective function after repetitive METH misuse.

Effects of length of abstinence on decision-making and craving in methamphetamine abusers

Rationale

The majority of drug abusers are incapable of sustaining abstinence over any length of time. Accumulating evidence has linked intense and involuntary craving, Impulsive decision-making and mood disturbances to risk for relapse. However, little is known about temporal changes of these neuropsychological functions in methamphetamine (METH)-dependent individuals.

Objectives

To investigate the effect of length of abstinence on decision-making, craving (baseline and cue-induced), and emotional state in METH-addicted individuals.

Methods

In this cross-sectional study, 183 adult METH-dependent patients at an addiction rehabilitation center who were abstinent for 6 days (n = 37), 14 days (n = 33), 1 month (n = 31), 3 months (n = 30), 6 months (n = 26), or 1 year (n = 30) and 39 healthy subjects were administered the Iowa Gambling Task (IGT) to assess decision-making performance. Depression, anxiety, and impulsivity were also examined. One hundred thirty-nine METH abusers who were abstinent for the aforementioned times then underwent a cue session, and subjective and physiological measures were assessed.

Results

METH dependent individuals who were abstinent for longer periods of time exhibited better decision-making than those who were abstinent for shorter periods of time. And self-reported emotional symptoms improved with abstinence. METH abusers’ ratings of craving decreased with the duration of abstinence, while cue-induced craving increased until 3 months of abstinence and decreased at 6 months and 1 year of abstinence.

Conclusions

We present time-dependent alterations in decision-making, emotional state, and the incubation of cue-induced craving in METH-dependent individuals, which might have significant clinical implications for the prevention of relapse.

Gender difference in the characteristics of and high-risk behaviours among non-injecting heterosexual methamphetamine users in Qingdao, Shandong Province, China

Background

Despite the increasing risk of HIV infections, few studies concerning the characteristics of non-injecting heterosexual methamphetamine (MA) users and related risk behaviours have been conducted in China.

Methods

Gender differences in socio-demographic characteristics, perception of MA and STD/HIV, MA use practices, and sexual behaviours related to MA use were examined among 398 non-injecting heterosexual MA users (288 males, 110 females).

Results

Male MA users were more likely to be married, local, and self-employed; female MA users were more likely to be young, single, engaged in commercial service or unemployed. Female MA users usually start MA use at an earlier age than males (24.3 vs. 31.3 years old), with shorter abuse durations (2.6 vs. 2.9 years), higher frequency of MA use (3.6 vs. 2.4 times per week), and higher likelihood of using MA with heterosexual partners (100% vs. 78.1%). More male MA users have had multiple sex partners (96.9% vs. 77.3%) and sex exchanges (72.9% vs. 46.4%). Among 277 males who had had sex with commercial sex workers (CSW), 69.4% never used condoms, and among 77 males who had had sex with multiple partners who are commercial sex workers and always or usually used condoms, 87.0% never changed condoms when changing partners.

Conclusion

There may be gender difference in the characteristics of high-risk behaviours among non-injecting heterosexual MA users. The findings suggest the integration of specific risk reduction strategies into intervention programs for non-injecting heterosexual MA user populations may significantly improve program goals.

The effects of vasopressin and oxytocin on methamphetamine-induced place preference behaviour in rats

Methamphetamine is a highly addictive stimulant drug whose illicit use and resultant addiction has become an alarming global phenomenon. The mesolimbic dopaminergic pathway has been shown to be fundamental to the establishment of addictive behaviour. This pathway, as part of the reward system of the brain, has also been shown to be important in classical conditioning, which is a learnt response. Within the modulation of learning and memory, the neurohypophyseal hormones vasopressin and oxytocin have been reported to play a vital role, with vasopressin exerting a long- term facilitatory effect and oxytocin exerting an inhibitory effect. Therefore we adopted a conditioned place preference model to investigate whether vasopressin V1b receptor antagonist SSR 149415 or oxytocin treatment would cause a decrease in the seeking behaviour in a reinstatement paradigm. Behavioural findings indicated that methamphetamine induced a change in the place preference in the majority of our animals. This change in place preference was not seen when vasopressin was administered during the extinction phase. On the other hand the methamphetamine-induced change in place preference was enhanced during the reinstatement phase in the animals that were treated with oxytocin. Striatal dopamine levels were determined, as methamphetamine is known to increase dopamine transmission in this area. Significant changes in dopamine levels were observed in some of our animals. Rats that received both methamphetamine and oxytocin had significantly higher striatal dopamine than those that received oxytocin alone. Western blot analysis for hippocampal cyclic AMP response element binding protein (CREB) was also conducted as a possible indicator of glutamatergic NMDA receptor activity, a pathway that is important for learning and memory. The Western blot analysis showed no changes in hippocampal pCREB expression. Overall our data led us to conclude that methamphetamine treatment can change place preference behaviour in rats and that this change may be partially restored by vasopressin antagonism, but exaggerated by oxytocin.

Individual, social, and environmental factors associated with initiating methamphetamine injection: implications for drug use and HIV prevention strategies

The purpose of this study was to determine the incidence and predictors of initiating methamphetamine injection among a cohort of injection drug users (IDU). We conducted a longitudinal analysis of IDU participating in a prospective study between June 2001 and May 2008 in Vancouver, Canada. IDU who had never reported injecting methamphetamine at the study's commencement were eligible. We used Cox proportional hazards models to identify the predictors of initiating methamphetamine injection. The outcome was time to first report of methamphetamine injection. Time-updated independent variables of interest included sociodemographic characteristics, drug use patterns, and social, economic and environmental factors. Of 1317 eligible individuals, the median age was 39.9 and 522 (39.6%) were female. At the study's conclusion, 200 (15.2%) participants had initiated injecting methamphetamine (incidence density: 4.3 per 100 person-years). In multivariate analysis, age (adjusted hazard ratio [aHR]: 0.96 per year older, 95%CI: 0.95-0.98), female sex (aHR: 0.58, 95%CI: 0.41-0.82), sexual abuse (aHR: 1.63, 95%CI: 1.18-2.23), using drugs in Vancouver's drug scene epicentre (aHR: 2.15 95%CI: 1.49-3.10), homelessness (aHR: 1.43, 95%CI: 1.01-2.04), non-injection crack cocaine use (aHR: 2.06, 95%CI: 1.36-3.14), and non-injection methamphetamine use (aHR: 3.69, 95%CI: 2.03-6.70) were associated with initiating methamphetamine injection. We observed a high incidence of methamphetamine initiation, particularly among young IDU, stimulant users, homeless individuals, and those involved in the city's open drug scene. These data should be useful for the development of a broad set of interventions aimed at reducing initiation into methamphetamine injection among IDU.

Crystal methamphetamine use among female street-based sex workers: Moving beyond individual-focused interventions

Given growing concern of the sexual risks associated with crystal methamphetamine use and the dearth of research characterizing the use of methamphetamine among street-based sex workers (FSWs), this study aimed to characterize the prevalence and individual, social, and structural contexts of crystal methamphetamine use among FSWs in a Canadian setting. Drawing on data from a prospective cohort, we constructed multivariate logistic models to examine independent correlates of crystal methamphetamine among FSWs over a two-year follow-up period using generalized estimating equations. Of a total of 255 street-based FSWs, 78 (32%) reported lifetime crystal methamphetamine use and 24% used crystal methamphetamine during the two-year follow-up period, with no significant associations between methamphetamine use and sexual risk patterns. In a final multivariate GEE model, FSWs who used crystal methamphetamine had a higher proportional odds of dual heroin injection (adjOR=2.98, 95%CI: 1.35-5.22), having a primary male sex partner who procures drugs for them (adjOR=1.79, 95%CI: 1.02-3.14), and working (adjOR=1.62, 95%CI: 1.04-2.65) and living (adjOR=1.41, 95%CI: 1.07-1.99) in marginalized public spaces. The findings highlight the crucial need to move beyond the individual to gender-focused safer environment interventions that mediate the physical and social risk environment of crystal methamphetamine use among FSWs.

Withdrawal symptoms in abstinent methamphetamine-dependent subjects

AIMS

Withdrawal symptoms have been linked to a propensity for relapse to drug abuse. Inasmuch as this association applies to methamphetamine (MA) abuse, an understanding of the course of MA withdrawal symptoms may help to direct treatment for MA dependence. Previous studies of symptoms manifested during abstinence from MA have been limited in size and scope. We asked (i) whether debilitating psychological and/or physical symptoms appear during the first several weeks of MA abstinence, (ii) how craving for MA evolves and (iii) whether psychiatric symptoms (e.g. depression, psychosis) persist beyond a month of abstinence.

DESIGN

A study of MA-dependent participants, who initiated and maintained abstinence from the drug for up to 5 weeks, compared to a matched healthy comparison group.

SETTING

In-patient research hospital ward (MA-dependent subjects) and out-patient (comparison subjects).

PARTICIPANTS

Fifty-six MA-dependent and eighty-nine comparison subjects.

MEASUREMENTS

Rater-assessed MA withdrawal questionnaire and self-report assessment of craving (MA-dependent subjects) and self-report assessment of psychiatric symptoms (both groups).

FINDINGS

At study entry, MA-dependent subjects exhibited a wide range in severity of depressive symptoms, with the average score at a mild-moderate level of severity. Symptoms of psychosis were also prevalent. While depressive and psychotic symptoms largely resolved within a week of abstinence, craving did not decrease significantly from the time of initiating abstinence until the second week, and then continued at a reduced level to the fifth week.

CONCLUSIONS

Depressive and psychotic symptoms accompany acute withdrawal from methamphetamine but resolve within 1 week. Craving is also present and lasts at least 5 weeks.

Effect of an electronic control device exposure on a methamphetamine-intoxicated animal model

OBJECTIVES

Because of the prevalence of methamphetamine abuse worldwide, it is not uncommon for subjects in law enforcement encounters to be methamphetamine-intoxicated. Methamphetamine has been present in arrest-related death cases in which an electronic control device (ECD) was used. The primary purpose of this study was to determine the cardiac effects of an ECD in a methamphetamine intoxication model.

METHODS

Sixteen anesthetized Dorset sheep (26-78 kg) received 0.0 mg/kg (control animals, n = 4), 0.5 mg/kg (n = 4), 1.0 mg/kg (n = 4), or 1.5 mg/kg (n = 4) of methamphetamine hydrochloride as a slow intravenous (IV) bolus during continuous cardiac monitoring. The animals received the following exposures in sequence from a TASER X26 ECD beginning at 30 minutes after the administration of the drug: 1) 5-second continuous exposure, 2) 15-second intermittent exposure, 3) 30-second intermittent exposure, and 4) 40-second intermittent exposure. Darts were inserted at the sternal notch and the cardiac apex, to a depth of 9 mm. Cardiac motion was determined by thoracotomy (smaller animals, < or = 32 kg) or echocardiography (larger animals, > 68 kg). Data were analyzed using descriptive statistics and chi-square tests.

RESULTS

Animals given methamphetamine demonstrated signs of methamphetamine toxicity with tachycardia, hypertension, and atrial and ventricular ectopy in the 30-minute period immediately after administration of the drug. Smaller animals (n = 8, < or = 32 kg, mean = 29.4 kg) had supraventricular dysrhythmias immediately after the ECD exposures. Larger animals (n = 8, > 68 kg, mean = 72.4) had only sinus tachycardia after the exposures. One of the smaller animals had frequent episodes of ventricular ectopy after two exposures, including runs of delayed onset, nonsustained six- to eight-beat unifocal and multifocal ventricular tachycardia that spontaneously resolved. This animal had significant ectopy prior to the exposures as well. Thoracotomy performed on three smaller animals demonstrated cardiac capture during ECD exposure consistent with previous animal studies. In the larger animals, none of the methamphetamine-intoxicated animals demonstrated cardiac capture. Two control sheep showed evidence of capture similar to the smaller animals. No ventricular fibrillation occurred after the exposure in any animal.

CONCLUSIONS

In smaller animals (32 kg or less), ECD exposure exacerbated atrial and ventricular irritability induced by methamphetamine intoxication, but this effect was not seen in larger, adult-sized animals. There were no episodes of ventricular fibrillation after exposure associated with ECD exposure in methamphetamine-intoxicated sheep.

Pilot safety evaluation of varenicline for the treatment of methamphetamine dependence

Despite the worldwide extent of methamphetamine dependence, no medication has been shown to effectively treat afflicted individuals. One relatively unexplored approach is modulation of cholinergic system function. Animal research suggests that enhancement of central cholinergic activity, possibly at nicotinic acetylcholine receptors (nAChRs), can reduce methamphetamine-related behaviors. Further, preliminary findings indicate that rivastigmine, a cholinesterase inhibitor, may reduce craving for methamphetamine after administration of the drug in human subjects. We therefore performed a double-blind, placebo-controlled, crossover pilot study of the safety and tolerability of varenicline in eight methamphetamine-dependent research subjects. Varenicline is used clinically to aid smoking cessation, and acts as a partial agonist at α4b2 nAChRs with full agonist properties at α7 nAChRs. Oral varenicline dose was titrated over one week to reach 1 mg twice daily, and then was co-administered with 30 mg methamphetamine, delivered in 10 intravenous (iv) infusions of 3 mg each. Varenicline was found to be safe in combination with iv methamphetamine, producing no cardiac rhythm disturbances or alterations in vital sign parameters. No adverse neuropsychiatric sequelae were detected either during varenicline titration or following administration of methamphetamine. The results suggest that varenicline warrants further investigation as a potential treatment for methamphetamine dependence.

Methamphetamine use and rates of incarceration among street-involved youth in a Canadian setting: a cross-sectional analysis

Background

Given concerns over rising use of methamphetamine, especially among street-involved youth, and the links between exposure to the correctional system and the production of drug-related harm, we sought to assess the relationship between ever using methamphetamine and reporting ever being incarcerated in the At-Risk Youth Survey (ARYS) in Vancouver, Canada.

Methods

The relationship between ever being imprisoned and ever using methamphetamine was estimated using a multivariate logistic regression analysis while also considering potentially confounding secondary demographic, social and behavioural variables.

Results

Of the 478 youth recruited into ARYS between September 2005 and October 2006, 385 (80.5%) reported ever being incarcerated overnight or longer. In the multivariate model, methamphetamine use was independently associated with ever being incarcerated (Adjusted Odds Ratio: 1.79, 95% Confidence Interval [CI]: 1.03 – 3.13).

Conclusion

Incarceration was very common in this cohort and strongly linked with ever using methamphetamine. This finding is of concern and, along with the previously identified risks of drug-related harm associated with incarceration, supports the development of novel public policy, such as community-based drug treatment, to address the use of methamphetamine among street youth.