Factors associated with methamphetamine withdrawal symptoms among people who inject drugs

Sex-specific Alterations in the mRNA Expression of Histone Deacetylases (HDACs) in the Rat Brain Following Prolonged Abstinence from Methamphetamine Self-administration

Methamphetamine (METH) use disorder (MUD) is a psychiatric disease that imposes substantial health burdens throughout the world. Significant sex-specific differences in misuse and relapse rates exist among human METH users and in preclinical models of MUD. We have been using a METH self-administration (SA) model to identify molecular substrates of sex-related behavioral manifestations. Rats were trained to self-administer METH (0.1 mg/kg/injection, i.v.) over 20 days. Hippocampus (HIP), prefrontal cortex (PFC), nucleus accumbens (NAc), and dorsal striatum (dSTR) were dissected and used to measure mRNA expression of HDACs because of their potential involvement in MUD. Compared to females, males self-administered more METH. Quantitative PCR revealed that control male rats had higher basal Hdac4 mRNA levels in their HIP and Hdac10 in the PFC in comparison to female controls. In contrast, female controls had higher basal levels of Hdac1, Hdac2, Hdac5, Hdac6, Hdac7, Hdac8, Sirt1, and Sirt2 mRNAs in the PFC. In addition, female METH takers showed decreased mRNA levels of Hdac1, Hdac2, Hdac3, Hdac4, Hdac5, Hdac6, Hdac7, Hdac8 and Hdac11 in their PFC when compared to female controls. Male METH rats had increased Hdac1, Hdac2, Hdac6, Sirt1, and Sirt2 mRNA levels in their PFC, but decreased Hdac4, Sirt4 and Sirt5 mRNA levels in HIP when compared to male controls. These results provide further evidence for sexual dimorphic responses to METH after a long withdrawal interval. These observations support the notion that sex-specific therapeutic approaches using epigenetic agents may be necessary against METH use disorder.

Housing and Displacement as Risk Factors for Negative Health Outcomes Among People Who Inject Drugs in Los Angeles, CA, and Denver, CO, USA

Background The United States is currently experiencing a housing and homelessness crisis. In response, many cities have adopted policies of displacement that move unhoused people from place to place. Recent research indicates that these policies may have negative health impacts on unhoused people who use drugs. We sought to examine health risks associated with government-enforced displacement among unhoused people who inject drugs (PWID). Methods We interviewed a community-recruited sample of opioid-using PWID in Los Angeles, CA and Denver, CO between April 2021 and November 2022 (N = 472) about their demographic/socioeconomic characteristics, drug use patterns, housing status, government-enforced displacement including items discarded during displacements, and health risks. We constructed binomial generalized linear regression to examine the risk ratio of non-fatal overdose, and syringe and cooker/cotton sharing between four groups of participants: housed, unhoused and not displaced, unhoused and relocated voluntarily, and unhoused and displaced in the last three months. Results In the last 3 months, 52% of participants were unhoused and displaced by the government. Among those who were displaced, median number of government-enforced displacements was 3 with 69% reporting loss of syringes, 56% loss of naloxone, and 22% loss of buprenorphine medicine. In multivariate models, risk ratios for unhoused and displaced participants were higher for nonfatal overdose and cooker/cotton sharing as compared to housed participants. Risk ratios for syringe sharing amongst unhoused participants did not differ significantly. Conclusions Unhoused and displaced PWID experience elevated health risks. Ending the use of government-enforced displacement of unhoused PWID is essential to reducing health risk in this population.

Locomotion changes in methamphetamine and amphetamine withdrawal: a systematic review

Despite extensive preclinical research over the years, a significant gap remains in our understanding of the specific effects of methamphetamine (METH) and amphetamine (AMPH) withdrawal. Understanding these differences could be pivotal to unveiling the unique pathophysiology underlying each stimulant. This may facilitate the development of targeted and effective treatment strategies tailored to the specific characteristics of each substance. Following PRISMA guidelines, this systematic review was conducted to examine alterations in spontaneous locomotor activity, specifically horizontal activity, in animals experiencing withdrawal from extended and repeated administration of AMPH or METH. Original articles were retrieved from four electronic databases, supplemented by a review of the references cited in the published papers. A total of thirty-one full-length articles (n = 31) were incorporated in the analysis. The results indicated that six studies documented a significant increase in horizontal activity among animals, seven studies reported decreased locomotion, and eighteen studies (8 AMPH; 10 METH) reported no significant alterations in the animals' locomotor activity. Studies reporting heightened locomotion mainly employed mice undergoing withdrawal from METH, studies reporting diminished locomotion predominantly involved rats undergoing withdrawal from AMPH, and studies reporting no significant changes in horizontal activity employed both rats and mice (12 rats; 6 mice). Drug characteristics, routes of administration, animal models, dosage regimens, duration, and assessment timing seem to influence the observed outcomes. Despite more than 50% of papers enlisted in this review indicate no significant changes in the locomotion during the stimulant withdrawal, the unique reactions of animals to withdrawal from METH and AMPH reported by some underscore the need for a more nuanced understanding of stimulant withdrawal.

Modeling methamphetamine use disorder in mammals: Sex differences in behavioral, biochemical, and transcriptional consequences

Methamphetamine (METH) is the most commonly misused amphetamine-type stimulant throughout the globe. METH is very rewarding, and its misuse can lead to a diagnosis of METH use disorder (MUD). Although METH use is observed in both sexes, there are, however, reported differences in the clinical manifestations of METH use and its consequences. These observations indicate the need for more research on the long-term sex-dependent consequences of METH taking in both preclinical and clinical settings. In effect, sex is a biological variable that can impact conclusions drawn from various basic and clinical studies. Thus, the present chapter provides a succinct review of the current state of the research on METH and its sex-associated consequences. In addition to behavioral and cognitive aspects of METH use, we discuss METH-induced changes in neurotransmitter systems and structures in the brain. Thus, the book chapter serves to highlight the significance of sex as a critical element that needs to be considered during discussions of novel therapeutic approaches to MUD.

"No Good Choice": What are the Issues of Having no Harm Reduction Strategies in Hospitals?

Background

Despite an increase in methamphetamine use and subsequent hospitalizations, the majority of Canadian hospitals currently lack harm reduction strategies for substance use. This can mean that people with lived experience of methamphetamine use are faced with a number of difficult decisions to make when admitted to hospital. Caring for people with lived experience of methamphetamine use can also be problematic with zero tolerance policies requiring abstinence to be maintained. This analysis set out to understand potential health care issues due to a lack of harm reduction strategies from the prospective of people with lived experience of methamphetamine use as well as health care/service professionals.

Methods

Based on a larger study, this secondary analysis explored issues discussed by people with lived experience of methamphetamine use and health care/service professionals regarding the challenges of providing harm reduction approaches in the hospital setting. A total of 108 individuals with lived experience of methamphetamine use completed a qualitative component of a mixed-method interview. In addition, 31 health care/service professionals participated in virtual focus groups and one-to-one interviews. Responses were analyzed using an ethnographic thematic approach.

Results

People with lived experience of methamphetamine use reported 3 choices upon admission: leave or avoid the hospital, stay but experience unsupported withdrawal, or stay but hide their substance usage from health care professionals. Health care/service professionals described 2 options: uphold zero tolerance that can lead to stigma and a lack of knowledge regarding addiction, or accept harm reduction but be unable to implement such strategies. This could lead to health being compromised due to policy and practice that requires abstinence. Neither group of participants described a good choice for them.

Conclusion

Current policy and education related to substance use needs to be revised.

Methamphetamine dependence in Australia-why is 'ice' (crystal meth) so addictive?

Australia has one of the highest rates in the world of the use of the crystalline form of methamphetamine, a highly addictive stimulant that is often associated with a chronic, relapsing dependency. Methamphetamine use is associated with both acquisitive and violent offending, which cause substantial personal and societal costs. Whilst the short-term euphoria and stimulation provide a positive reinforcement to methamphetamine use, the aversive states of withdrawing from methamphetamine and the associated craving, which may last up to five weeks into abstinence, underlie the negative reinforcement to continued methamphetamine use. Although many methamphetamine-dependent users experience high levels of psychological distress, it is likely that less than half engage with treatment or support services, and current intervention and treatment programmes have high discontinuation rates. Stigma and discrimination, even from paramedics and health clinicians, are prominent barriers to methamphetamine-dependent users accessing treatment in Australia.

The impact of opioid-stimulant co-use on tonic and cue-induced craving

The twin opioid-stimulant epidemics have led to increased overdose deaths and present unique challenges for individuals entering treatment with opioid-stimulant polysubstance use. This study examined tonic and cue-induced craving as a primary outcome among persons in substance use treatment who reported primary substances of opioids, methamphetamine, or cocaine. The sample consisted of 1974 individuals in 55 residential substance-use treatment centers in the United States in 2021. Weekly surveys were delivered via a third-party outcomes tracking system, including measures of tonic and cue-induced craving. Initial comparisons on tonic and cue-induced craving were made among those who primarily used opioids, cocaine, or methamphetamine. Further, the effect of opioid/stimulant polysubstance use on tonic and cue-induced craving was evaluated using marginal effect regression models. Primary methamphetamine use was associated with decreased tonic craving compared to primary opioid use (β = -5.63, p < 0.001) and primary cocaine use was also associate with decreased tonic craving compared to primary opioid use (β = -6.14, p < 0.001). Primary cocaine use was also associated with lower cue-induced cravings compared to primary opioid use (β = -0.53, p = 0.037). Opioid-methamphetamine polysubstance use was associated with higher tonic craving (β = 3.81, p = <0.001) and higher cue-induced craving (β = 1.55, p = 0.001); however, this was not the case for opioid-cocaine polysubstance use. The results of this study indicate that individuals who primarily use opioids and have secondary methamphetamine use experience higher cue-induced and tonic-induced craving, suggesting that these individuals may benefit from additional interventions that target craving and mitigate relapse risk and other negative sequelae.

Clinical management of psychostimulant withdrawal: review of the evidence

It is estimated that a majority of people who use psychostimulants, particularly methamphetamine (MA) and cocaine, experience withdrawal upon abstinence from sustained use. This review of clinical research reports the evidence regarding biomedical and behavioral treatments for psychostimulant withdrawal symptoms. It provides a framework for clinicians and scientists to increase impact on attenuating MA and cocaine withdrawal during initial and sustained abstinence. Articles reviewed included reports of controlled clinical trials (randomized or non-randomized) reporting at least one withdrawal symptom among the outcomes or specifically studying patients in withdrawal. Potential efficacy for MA withdrawal is noted for a few medications (mirtazapine, naltrexone, bupropion) and repetitive transcranial magnetic stimulation during acute (first week), early protracted (weeks 2-4) and late protracted (> 4 weeks) withdrawal phases. Topiramate shows mixed evidence of efficacy for cocaine withdrawal. In general, there is inconsistent signal for biomedical and behavioral treatments on MA and cocaine withdrawal.

Differences in clinical features and gut microbiota between individuals with methamphetamine casual use and methamphetamine use disorder

Background

The transition from methamphetamine (MA) casual use (MCU) to compulsive use is enigmatic as some MA users can remain in casual use, but some cannot. There is a knowledge gap if gut microbiota (GM) play a role in differing MCU from MA use disorder (MUD). We aimed to investigate the clinical features and GM differences between individuals with MCU and MUD.

Method

We recruited two groups of MA users -MCU and MUD - and matched them according to age and body mass index (n=21 in each group). Participants were accessed using the Semi-Structured Assessment for Drug Dependence and Alcoholism, and their fecal samples were undergone 16S ribosomal DNA sequencing. We compared the hosts' clinical features and GM diversity, composition, and structure (represented by enterotypes) between the two groups. We have identified differential microbes between the two groups and performed network analyses connecting GM and the clinical traits.

Result

Compared with the casual users, individuals with MUD had higher incidences of MA-induced neuropsychiatric symptoms (e.g., paranoia, depression) and withdrawal symptoms (e.g., fatigue, drowsiness, and increased appetite), as well as stronger cravings for and intentions to use MA, and increased MA tolerance. The GM diversity showed no significant differences between the two groups, but four genera (Halomonas, Clostridium, Devosia, and Dorea) were enriched in the individuals with MUD (p<0.05). Three distinct enterotypes were identified in all MA users, and Ruminococcus-driven enterotype 2 was dominant in individuals with MUD compared to the MCU (61.90% vs. 28.60%, p=0.03). Network analysis shows that Devosia is the hub genus (hub index = 0.75), which is not only related to the counts of the MUD diagnostic criteria (ρ=0.40; p=0.01) but also to the clinical features of MA users such as reduced social activities (ρ=0.54; p<0.01). Devosia is also associated with the increased intention to use MA (ρ=0.48; p<0.01), increased MA tolerance (ρ=0.38; p=0.01), craving for MA (ρ=0.37; p=0.01), and MA-induced withdrawal symptoms (p<0.05).

Conclusion

Our findings suggest that Ruminococcus-driven enterotype 2 and the genera Devosia might be two influential factors that differentiate MA casual use from MUD, but further studies are warranted.

Nanowired Delivery of Curcumin Attenuates Methamphetamine Neurotoxicity and Elevates Levels of Dopamine and Brain-Derived Neurotrophic Factor

Curcumin is a well-known antioxidant used as traditional medicine in China and India since ages to treat variety of inflammatory ailments as a food supplement. Curcumin has antitumor properties with neuroprotective effects in Alzheimer's disease. Curcumin elevates brain-derived neurotrophic factor (BDNF) and dopamine (DA) levels in the brain indicating its role in substance abuse. Methamphetamine (METH) is one of the most abused substances in the world that induces profound neurotoxicity by inducing breakdown of the blood-brain barrier (BBB), vasogenic edema and cellular injuries. However, influence of curcumin on METH-induced neurotoxicity is still not well investigated. In this investigation, METH neurotoxicity and neuroprotective effects of curcumin nanodelivery were examined in a rat model. METH (20 mg/kg, i.p.) neurotoxicity is evident 4 h after its administration exhibiting breakdown of BBB to Evans blue albumin in the cerebral cortex, hippocampus, cerebellum, thalamus and hypothalamus associated with vasogenic brain edema as seen measured using water content in all these regions. Nissl attaining exhibited profound neuronal injuries in the regions of BBB damage. Normal curcumin (50 mg/kg, i.v.) 30 min after METH administration was able to reduce BBB breakdown and brain edema partially in some of the above brain regions. However, TiO₂ nanowired delivery of curcumin (25 mg/kg, i.v.) significantly attenuated brain edema, neuronal injuries and the BBB leakage in all the brain areas. BDNF level showed a significant higher level in METH-treated rats as compared to saline-treated METH group. Significantly enhanced DA levels in METH-treated rats were also observed with nanowired delivery of curcumin. Normal curcumin was able to slightly elevate DA and BDNF levels in the selected brain regions. Taken together, our observations are the first to show that nanodelivery of curcumin induces superior neuroprotection in METH neurotoxicity probable by enhancing BDNF and DA levels in the brain, not reported earlier.

Increases in methamphetamine injection among treatment admissions in the U.S

BACKGROUND

Prior research indicates rising methamphetamine use and harms in the U.S., potentially related to increases in methamphetamine injection. To date, research on trends and correlates of methamphetamine injection is limited.

METHODS

Analysis of trends and correlates of methamphetamine injection among treatment admissions among persons aged ≥ 12 whose primary substance of use at admission is methamphetamine. Data are from the Treatment Episode Data Set. Analyses includes descriptive statistics, trend analyses, and multilevel multivariable logistic regression.

RESULTS

Primary methamphetamine treatment admissions increased from 138,379 in 2010 to 201,021 in 2019. Among primary methamphetamine admissions, injection as the usual route of use increased from 24,821 (18.0 % of admissions) in 2010 to 55,951 (28.2 % of admissions) in 2019. Characteristics associated with increased adjusted odds of reporting methamphetamine injection included: males (aOR = 1.13, 95 % CI = 1.10-1.15); admission age 25-34 years (aOR = 1.23, 95 % CI = 1.19-1.28) and 35-44 years (aOR = 1.12, 95 % CI = 1.08-1.17) compared to age 18-24; dependent living (aOR = 1.33, 95 % CI = 1.29-1.37) and homelessness (aOR = 1.58, 95 % CI = 1.54-1.63) compared to independent living; part-time employment (aOR = 1.08, 95 % CI = 1.02-1.14), unemployment (aOR = 1.39, 95 % CI = 1.34-1.44) and not in labor force (aOR = 1.43, 95 % CI = 1.37-1.49) compared to full-time employment; one to ≥ four prior treatment admissions (aORs ranging from 1.19 to 1.94) compared to no prior admissions; also reporting use of cocaine (aOR = 1.10, 95 % CI = 1.05-1.16), heroin (aOR = 3.52, 95 % CI = 3.40-3.66), prescription opioids (aOR = 1.61, 95 % CI = 1.54-1.67), or benzodiazepines (aOR = 1.42, 95 % CI = 1.32-1.52) at treatment admission.

CONCLUSIONS

Findings lend further evidence to a resurgence of methamphetamine use that is intertwined with the ongoing opioid crisis in the U.S. Efforts to expand evidence-based prevention, treatment, and response efforts, particularly to populations at highest risk, are urgently needed.

Contrasting dose-dependent effects of acute intravenous methamphetamine on lateral hypothalamic extracellular glucose dynamics in male and female rats

Glucose is the brain's primary energetic resource. The brain's use of glucose is dynamic, balancing delivery from the neurovasculature with local metabolism. Although glucose metabolism is known to differ in humans with and without methamphetamine use disorder (MUD), it is unknown how central glucose regulation changes with acute methamphetamine experience. Here, we determined how intravenous methamphetamine regulates extracellular glucose levels in a brain region implicated in MUD-like behavior, the lateral hypothalamus (LH). We measured extracellular LH glucose in awake adult male and female drug-naive Wistar rats using enzyme-linked amperometric glucose biosensors. Changes in LH glucose were monitored during a single session after: 1) natural nondrug stimuli (novel object presentation and a tail-touch), 2) increasing cumulative doses of intravenous methamphetamine (0.025, 0.05, 0.1, and 0.2 mg/kg), and 3) an injection of 60 mg of glucose. We found second-scale fluctuations in LH glucose in response to natural stimuli that differed by both stimulus type and sex. Although rapid, second-scale changes in LH glucose during methamphetamine injections were variable, slow, minute-scale changes following most injections were robust and resulted in a reduction in LH glucose levels. Dose and sex differences at this timescale indicated that female rats may be more sensitive to the impact of methamphetamine on central glucose regulation. These findings suggest that the effects of MUD on healthy brain function may be linked to how methamphetamine alters extracellular glucose regulation in the LH and point to possible mechanisms by which methamphetamine influences central glucose metabolism more broadly.NEW & NOTEWORTHY Enzyme-linked glucose biosensors were used to monitor lateral hypothalamic (LH) extracellular fluctuations during nondrug stimuli and intravenous methamphetamine injections in drug-naive awake male and female rats. Second-scale glucose changes occurred after nondrug stimuli, differing by modality and sex. Robust minute-scale decreases followed most methamphetamine injections. Sex differences at the minute-scale indicate female central glucose regulation is more sensitive to methamphetamine effects. We discuss likely mechanisms underlying these fluctuations, and their implications in methamphetamine use disorder.

Exercise modulates central and peripheral inflammatory responses and ameliorates methamphetamine-induced anxiety-like symptoms in mice

Anxiety-like symptoms are common symptoms of methamphetamine (METH) users, especially in the acute withdrawal period, which is an important factor for the high relapse rate during METH acute withdrawal. Exercise has been demonstrated to relieve anxiety-like symptoms during METH withdrawal, but the underlying mechanisms of this anti-anxiety effect are still unclear. Activated microglia and abnormal neuroinflammation play an important role in the pathogenesis of anxiety-like symptoms after METH withdrawal. Moreover, peripheral immune factors were also significantly associated with anxiety symptoms. However, the effects of treadmill exercise on microglial function and neuroinflammation in the striatum and hippocampus during acute METH withdrawal have not been reported. In the current study, we found severe peripheral immune dysfunction in METH users during acute withdrawal, which may in part contribute to anxiety symptoms during METH acute withdrawal. We also showed that 2 weeks of METH exposure induced anxiety-like symptoms in the acute withdrawal period. Additionally, METH exposure resulted in increased microglial activation and proinflammatory cytokines released in the mouse striatum and hippocampus during acute withdrawal. We next evaluated the effects of treadmill exercise in countering anxiety-like symptoms induced by METH acute withdrawal. The results showed that anxiety-like symptoms induced by acute METH withdrawal were attenuated by coadministration of treadmill exercise. In addition, treadmill exercise counteracted METH-induced microglial activation in the mouse striatum and various subregions of the hippocampus. Furthermore, treadmill exercise also reversed the increase in proinflammatory cytokines induced by acute METH withdrawal in the mouse striatum, hippocampus and serum. Our findings suggest that the anti-anxiety effect of treadmill exercise may be mediated by reducing microglial activation and regulating central and peripheral inflammatory responses.

Effects of resilience on impulsivity, cognition and depression during protracted withdrawal among Chinese male methamphetamine users

BACKGROUND

Methamphetamine (METH) dependence is a complex and dynamic public health problem. Long-term abuse of METH can increase numerous risks of mental and physical problems. Currently, the methods to reduce METH dependence and improve the withdrawal symptoms are limited and ineffective. Resilience is seen as a multidimensional and dynamic capability to recover or bounce back from stressful events and is also generally considered as a protective factor against mental dysfunction.

METHODS

One hundred thirty-four males with METH dependence were consecutively recruited from Huanglong Compulsory Isolated Detoxification Center between 2019 and 2021, of whom 112 were into the group. The Connor-Davidson Resilience Scale (CD-RISC), Self-rating depression scale (SDS), Self-rating anxiety scale (SAS), Barratt Impulsiveness Scale-11(BIS-11), and the Repeatable Battery for the Assessment of Neuropsychological Status (Rbans) were used to evaluate resilience, depression, anxiety, impulsivity, and cognition respectively.

RESULTS

The results mainly indicated that high resilience group showed lower SDS, SAS and BIS-11 scores than low resilience group (all p < 0.05). Besides, the total scores of Rbans were higher in high resilience groups than low resilience group (both p < 0.05). Moreover, linear regression results showed that resilience may be influenced by the scores of SDS and SAS.

CONCLUSIONS

Resilience is negatively correlated with impulsivity and depression. Besides, it is also positively associated with cognitive function. Drug users with higher resilience may have a strong ability to mobilize psychological resources to create a good psychological environment, which may have a positive effect on the relief or improvement of symptoms.

Sex differences in methamphetamine use disorder perused from pre-clinical and clinical studies: Potential therapeutic impacts

Methamphetamine (METH) use, and misuse are associated with severe socioeconomic consequences. METH users develop tolerance, lose control over drug taking behaviors, and suffer frequent relapses even during treatment. The clinical course of METH use disorder is influenced by multifactorial METH-induced effects on the central and peripheral nervous systems. Although these METH-induced consequences are observed in humans of all ages, races, and sexes, sexual dimorphism in these outcomes have been observed in both pre-clinical and clinical settings. In this review, we have provided a detailed presentation of the sex differences reported in human and animal studies. We have therefore presented data that identified the influences of sex on METH pharmacokinetics, METH-induced changes in behaviors, cognitive processes, structural changes in the brain, and the effects of the drug on neurotransmitter systems and molecular mechanisms. Finally, we highlighted the potential significance of sex as a critical variable that should be considered when planning the development of new pharmacotherapeutic approaches against MEH use disorder in humans.

Goofballing of Opioid and Methamphetamine: The Science Behind the Deadly Cocktail

Globally, millions of people suffer from various substance use disorders (SUD), including mono-and polydrug use of opioids and methamphetamine. Brain regions such as the cingulate cortex, infralimbic cortex, dorsal striatum, nucleus accumbens, basolateral and central amygdala have been shown to play important roles in addiction-related behavioral changes. Clinical and pre-clinical studies have characterized these brain regions and their corresponding neurochemical changes in numerous phases of drug dependence such as acute drug use, intoxication, craving, withdrawal, and relapse. At present, many studies have reported the individual effects of opioids and methamphetamine. However, little is known about their combined effects. Co-use of these drugs produces effects greater than either drug alone, where one decreases the side effects of the other, and the combination produces a prolonged intoxication period or a more desirable intoxication effect. An increasing number of studies have associated polydrug abuse with poorer treatment outcomes, drug-related deaths, and more severe psychopathologies. To date, the pharmacological treatment efficacy for polydrug abuse is vague, and still at the experimental stage. This present review discusses the human and animal behavioral, neuroanatomical, and neurochemical changes underlying both morphine and methamphetamine dependence separately, as well as its combination. This narrative review also delineates the recent advances in the pharmacotherapy of mono- and poly drug-use of opioids and methamphetamine at clinical and preclinical stages.