Patients with methamphetamine psychosis admitted to a psychiatric hospital in Japan. A preliminary report

Assessment of resting cerebral perfusion between methamphetamine-associated psychosis and schizophrenia through arterial spin labeling MRI

OBJECTIVE

The clinical manifestations of methamphetamine (METH)-associated psychosis (MAP) and acute paranoid schizophrenia (SCZ) are similar. This study aims to assess regional cerebral blood flow (rCBF) in individuals who use METH and in those with SCZ using the MRI arterial spin labeling (ASL) technique.

METHODS

We prospectively recruited 68 participants and divided them into four groups: MAP (N = 15), SCZ (N = 13), METH users with no psychosis (MNP; N = 22), and normal healthy controls (CRL; N = 18). We measured rCBF using an MRI three-dimensional pseudo-continuous ASL sequence. Clinical variables were assessed using the Positive and Negative Syndrome Scale (PANSS) and Brief Assessment of Cognition in Schizophrenia (BACS). Group-level rCBF differences were analyzed using a two-sample t-test.

RESULTS

Decreased rCBF was found in the precuneus, premotor cortex, caudate nucleus, dorsolateral prefrontal cortex, and thalamus in the MNP group compared with the CRL group. The MAP group had significantly decreased rCBF in the precuneus, hippocampus, anterior insula, inferior temporal gyrus, inferior orbitofrontal gyrus, and superior occipital gyrus compared with the MNP group. Increased rCBF in the precuneus and premotor cortex was seen in the MAP group compared with the SCZ group. rCBF in the precuneus and premotor cortex significantly correlated negatively with the PANSS but correlated positively with BACS scores in the MAP and SCZ groups.

CONCLUSION

METH exposure was associated with decreased rCBF in the precuneus and premotor cortex. Patients with MAP exhibited higher rCBF than those with SCZ, implying preserved insight and favorable outcomes. rCBF can therefore potentially serve as a diagnostic approach to differentiate patients with MAP from those with SCZ.

A 6-Month Follow-Up Study: Cognitive Impairment May Predict More Frequent Use of Methamphetamine

Objectives

Methamphetamine (METH) use has been associated with impairments in a variety of cognitive functions. In this study, it was aimed to assess the relation between cognitive measures and frequency of METH use.

Methods

Ninety-eight participants with methamphetamine use disorder were assessed with Wisconsin Card Sorting Test (WCST), Victoria-Stroop Word Color Test (SWCT), Trail Making Test (TMT) A and B. Participants were followed up during 6-month period with multiple urine toxicology tests (at baseline, month 1, month 2, month 3 and month 6).

Results

Participants who had their prescriptions regularly were more likely to have higher rates of METH-negative urine results (P = .003). Participants who had more correct numbers, completed more categories and had more conceptual level responses on WCST were more likely to use lower frequency of METH (OR = 0.006, P < .01; OR = 0.171, P < .001; OR = 0.024, P < .001; respectively). The higher error numbers and perseverative error rates on WCST were associated with more frequent METH use (OR = 0.023, P < .001; OR = 0.076, P < .001). Interference factor on SWCT was related with lower frequency of METH use whereas color naming factor on SWCT was related with higher rates of urine results (OR = 0.012, P < .001; OR = 3.628, P < .001; respectively). Higher TMT B-A score was related with more frequent METH use, although the significance disappeared after adjustment (OR = 0.002, P < .001). Having psychotic symptoms predicted less frequent use, but after adjustment for other significant variables, there was no significance.

Conclusion

Lower frequency of METH use in the follow-up could be predicted by neurocognitive assessments. Deficits in executive functions, attention, set-shifting and mental flexibility seems to be the most effected domains and this effect may be independent from the severity of psychotic symptoms.

Substance use, microbiome and psychiatric disorders

Accumulating evidence from several studies has shown association between substance use, dysregulation of the microbiome and psychiatric disorders such as depression, anxiety, and psychosis. Many of the abused substances such as cocaine and alcohol have been shown to alter immune signaling pathways and cause inflammation in both the periphery and the central nervous system (CNS). In addition, these substances of abuse also alter the composition and function of the gut microbiome which is known to play important roles such as the synthesis of neurotransmitters and metabolites, that affect the CNS homeostasis and consequent behavioral outcomes. The emerging interactions between substance use, microbiome and CNS neurochemical alterations could contribute to the development of psychiatric disorders. This review provides an overview of the associative effects of substance use such as alcohol, cocaine, methamphetamine, nicotine and opioids on the gut microbiome and psychiatric disorders involving anxiety, depression and psychosis. Understanding the relationship between substance use, microbiome and psychiatric disorders will provide insights for potential therapeutic targets, aimed at mitigating these adverse outcomes.

Substance-Induced Psychoses: An Updated Literature Review

Background: On the current psychopharmacological panorama, the variety of substances able to provoke an episode of acute psychosis is rapidly increasing. Such psychotic episodes are classified according to the major category of symptoms: positive, negative, or cognitive psychotic episodes. On one hand, the abuse of methamphetamines, cannabis, and cocaine plays a big role in increasing the incidence of episodes resembling a psychotic disorder. On the other hand, the progress in terms of pharmacodynamics knowledge has led to the synthesis of new drugs, such as cannabinoids and cathinone's, which have rapidly entered into the common pool of abusers' habits. Regarding these newly synthesized substances of abuse, further clinical studies are needed to understand their psychogenic properties. The topic of this review is complicated due to the frequent abuse of psychotomimetic drugs by patients affected by psychotic disorders, a fact that makes it extremely difficult to distinguish between an induced psychosis and a re-exacerbation of a previously diagnosed disorder. Methods: The present narrative review summarizes results from clinical studies, thus investigating the psychotogenic properties of abused substances and the psychotic symptoms they can give rise to. It also discusses the association between substance abuse and psychosis, especially with regards to the differential diagnosis between a primary vs. a substance-induced psychotic disorder. Findings: Our findings support the theory that psychosis due to substance abuse is commonly observed in clinical practice. The propensity to develop psychosis seems to be a function of the severity of use and addiction. Of note, from a phenomenological point of view, it is possible to identify some elements that may help clinicians involved in differential diagnoses between primary and substance-induced psychoses. There remains a striking paucity of information on the outcomes, treatments, and best practices of substance-induced psychotic episodes.

Chronic methamphetamine interacts with BDNF Val66Met to remodel psychosis pathways in the mesocorticolimbic proteome

Methamphetamine (Meth) abuse has reached epidemic proportions in many countries and can induce psychotic episodes mimicking the clinical profile of schizophrenia. Brain-derived neurotrophic factor (BDNF) is implicated in both Meth effects and schizophrenia. We therefore studied the long-term effects of chronic Meth exposure in transgenic mice engineered to harbor the human BDNF^Val66Met polymorphism expressed via endogenous mouse promoters. These mice were chronically treated with an escalating Meth regime during late adolescence. At least 4 weeks later, all hBDNF^Val66Met Meth-treated mice exhibited sensitization confirming persistent behavioral effects of Meth. We used high-resolution quantitative mass spectrometry-based proteomics to biochemically map the long-term effects of Meth within the brain, resulting in the unbiased detection of 4808 proteins across the mesocorticolimbic circuitry. Meth differentially altered dopamine signaling markers (e.g., Dat, Comt, and Th) between hBDNF^Val/Val and hBDNF^Met/Met mice, implicating involvement of BDNF in Meth-induced reprogramming of the mesolimbic proteome. Targeted analysis of 336 schizophrenia-risk genes, as well as 82 growth factor cascade markers, similarly revealed that hBDNF^Val66Met genotype gated the recruitment of these factors by Meth in a region-specific manner. Cumulatively, these data represent the first comprehensive analysis of the long-term effects of chronic Meth exposure within the mesocorticolimbic circuitry. In addition, these data reveal that long-term Meth-induced brain changes are strongly dependent upon BDNF genetic variation, illustrating how drug-induced psychosis may be modulated at the molecular level by a single genetic locus.

Treatment Response Distinguishes Persistent Type of Methamphetamine Psychosis From Schizophrenia Spectrum Disorder Among Inmates at Japanese Medical Prison

Introduction: Persistent methamphetamine-associated psychosis (pMAP) is a disorder similar to schizophrenia, so much so that the differences in clinical symptoms and treatment response between the two remain unknown. In this study, we compared the features of pMAP with those of schizophrenia spectrum disorders (SSD). Materials and Methods: This was a retrospective quasi-experimental case-control study of inmates in a medical prison. The behavioral problems, clinical symptoms, and chlorpromazine (CP)-equivalent doses of 24 patients with pMAP and 27 with SSD were compared. Results: Patients in the pMAP group were hospitalized for fewer days than those in the SSD group (281.5 vs. 509.5; p = 0.012), but there were no other significant group differences in behavioral problems or clinical symptoms. The pMAP group received fewer antipsychotics in CP-equivalent doses than the SSD group at 4, 8, and 12 weeks after admission and at the time of discharge (p = 0.018, 0.001, 0.007, and 0.023, respectively). The number of CP-equivalent doses in the SSD group tended to increase after admission, but not in the pMAP group. Discussion: These findings suggest that differentiation between pMAP and SSD based on behavior and symptoms alone may be difficult, and that patients with pMAP may respond better to treatment with a lower dose of antipsychotic medication than those with SSD. Further confirmatory studies are warranted.

Differences in the amplitude of low-frequency fluctuation between methamphetamine and heroin use disorder individuals: A resting-state fMRI study

INTRODUCTION

Methamphetamine has surpassed heroin as the most popular abused drug in China. Although the use of both heroin and methamphetamine leads to use disorders through dysfunction of the dopamine pathway, the incidence of psychiatric disorder caused by methamphetamine abuse is higher than the incidence of psychiatric disorder caused by heroin abuse. The difference in resting-state function between heroin use disorder (HUD) and methamphetamine use disorder (MAUD) and the relationship between resting-state function and psychiatric disorder related to MAUD are unknown.

METHODS

In the present study, 21 male individuals with MAUD, 21 demographically matched individuals with HUD, and 21 normal controls (NC) were recruited. The amplitude of low-frequency fluctuation (ALFF) during resting-state brain function was measured by magnetic resonance imaging. Psychiatric status was evaluated by the Symptom Checklist-90 (SCL90).

RESULTS

Individuals with MAUD had increased SCL90 scores compared to those of the NC for anxiety, paranoia, and additional items, and the hostility score was significantly increased compared to that of individuals with HUD. There is no significant difference between HUD and NC individuals. Individuals with MAUD had increased ALFF compared to those of the NC for thalamus, right postcentral, and right inferior temporal gyri, but a decreased ALFF in the cerebellum. Individuals with HUD had significantly increased ALFF compared to those of the NC for left middle frontal gyrus but a decreased ALFF in the left postcentral gyrus. Individuals with MAUD had significantly increased ALFF compared to those of the HUD for thalamus, the right inferior temporal, and bilateral postcentral gyri, and the ALFF of cerebellum and left middle frontal was significantly increased.

CONCLUSIONS

Methamphetamine can induce more serious psychiatric disorders than heroin. The resting-state function involved in mood adjustment, the auditory, and memory-related brain regions may affect psychotic symptoms related to MAUD.

Methamphetamine-associated psychosis: Clinical presentation, biological basis, and treatment options

INTRODUCTION

Methamphetamine associated psychosis (MAP) represents a mental disorder induced by chronic methamphetamine use in a subset of users. The prevalence of the disorder has increased in several countries in Europe and Asia where methamphetamine use has increased. MAP remains difficult to distinguish from primary psychiatric disorders, especially schizophrenia, creating complications in prescribing treatment plans to patients.

DESIGN

This narrative review sought to summarize difficulties related to MAP diagnosis and highlight the need for a better treatment model. Current best practices are described and potential novel therapies and future research suggested.

RESULTS

Results suggest that clear biological and clinical differences appear between patients presenting with MAP and schizophrenia and that there may exist distinct subgroups within MAP itself. MAP-specific treatment studies have been few and have focused on the use of antipsychotic medication. Antipsychotic treatment has been shown to alleviate the psychotic symptoms of MAP but produce debilitating adverse effects and fail to adequately address methamphetamine use in patients.

CONCLUSIONS

Continued identification of subgroups within the heterogenous MAP population may lead to better diagnosis, treatment, and outcomes for patients. Psychosocial therapies should be explored in addressing the cooccurring substance use and psychosis in the treatment of MAP.

A case of methamphetamine use disorder presenting a condition of ultra-rapid cycler bipolar disorder

Methamphetamine, a potent psychostimulant, may cause a condition of mood disorder among users. However, arguments concerning methamphetamine-induced mood disorder remain insufficient. This case study describes a male with methamphetamine-induced bipolar disorder not accompanied by psychotic symptoms, who twice in an 11-year treatment period, manifested an ultra-rapid cycler condition alternating between manic and depressive mood states with 3- to 7-day durations for each. The conditions ensued after a bout of high-dose methamphetamine use and shifted to a moderately depressive condition within 1 month after the use under a treatment regimen of aripiprazole and mood stabilizers. The cycler condition may be characteristic of a type of the bipolar disorder and a sign usable for characterization. Further efforts are needed to seek distinctive features and to improve diagnostic assessment of methamphetamine-induced mood disorders.

A Systematic Review of the Symptom Profile and Course of Methamphetamine-Associated PsychosisSubstance Use and Misuse

OBJECTIVES

The psychiatric symptom profile of methamphetamine-associated psychosis (MAP) has varied considerably across studies of different research designs. We performed a systematic review to examine the available evidence for specific psychotic symptoms associated with MAP, including the clinical course and longitudinal changes in this symptom profile.

METHODS

Five key electronic databases were searched to identify studies that examined the symptom profile or clinical course of MAP in individuals identified as having MAP. The reporting of specific psychiatric symptoms, and duration of symptoms where available, was recorded for each study.

RESULTS

Ninety-four articles were identified (n = 7387), including case-control (k = 29), cross-sectional (k = 20), experimental (k = 6), case report (k = 29), and longitudinal (k = 20) studies. Persecutory delusions, auditory and visual auditory hallucinations were by far the most commonly reported symptoms (reported in 65-84% of studies). Hostility, conceptual disorganization, and depression were reported in a large proportion of studies (31-53%). Negative symptoms were mostly absent (<20%). The median percentage of participants with persistent psychotic symptoms (>1 month duration) across studies was 25% (excluding case reports).

CONCLUSION

Persecutory delusions, auditory and visual hallucinations, hostility, depression and conceptual disorganization are central to MAP, whereas negative psychotic symptoms are typically absent. An overrepresentation of institutionalized or male participants may have overemphasized negative symptoms and underreported affective symptoms in past research. Symptoms of MAP may persist beyond one month after drug cessation in some individuals. Clinicians are encouraged to manage affective symptoms in MAP individuals, and monitor for the development of chronic psychotic symptoms.

Methamphetamine dependence with and without psychotic symptoms: A multi-modal brain imaging study

OBJECTIVE

Methamphetamine dependence can lead to psychotic symptoms which may be mediated by frontal, striatal, limbic, and thalamic regions. There are few neuroimaging data that allow comparison of individuals with methamphetamine dependence who do, and do not, have psychosis. Two complementary imaging techniques were employed to investigate neurocircuitry associated with methamphetamine dependence with and without psychotic symptoms.

METHODS

Three groups of participants were recruited: methamphetamine dependent (MAA) (N = 11), methamphetamine dependent with psychotic symptoms (MAP) (N = 14), and controls (N = 14). Resting brain glucose metabolism was measured using [¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography (PET) and cerebral perfusion was assessed using arterial spin labelling (ASL) magnetic resonance imaging.

RESULTS

Methamphetamine abusers (MAA and MAP groups) had decreased glucose metabolism compared to healthy controls in the left insula, left precentral gyrus, and the anterior cingulate cortex. Compared to MAA participants, MAP participants had 1) decreased glucose metabolism in the left precentral gyrus and the left inferior frontal gyrus and 2) increased glucose metabolism in the putamen and pallidum. MAP participants also had increased cerebral perfusion in the right putamen and right pallidum compared to MAA.

CONCLUSION

Findings support the involvement of frontal, striatal, and limbic regions in methamphetamine dependence. Furthermore, they indicate that glucose metabolism and cerebral perfusion in these regions are disrupted in methamphetamine dependent individuals with psychotic symptoms.

A Comparison of Methamphetamine-Induced Psychosis and Schizophrenia: A Review of Positive, Negative, and Cognitive Symptomatology

Methamphetamine is a potent psychostimulant that can induce psychosis among recreational and chronic users, with some users developing a persistent psychotic syndrome that shows similarities to schizophrenia. This review provides a comprehensive critique of research that has directly compared schizophrenia with acute and chronic METH psychosis, with particular focus on psychiatric and neurocognitive symptomatology. We conclude that while there is considerable overlap in the behavioral and cognitive symptoms between METH psychosis and schizophrenia, there appears to be some evidence that suggests there are divergent aspects to each condition, particularly with acute METH psychosis. Schizophrenia appears to be associated with pronounced thought disorder, negative symptoms more generally and cognitive deficits mediated by the parietal cortex, such as difficulties with selective visual attention, while visual and tactile hallucinations appear to be more prevalent in acute METH-induced psychosis. As such, acute METH psychosis may represent a distinct psychotic disorder to schizophrenia and could be clinically distinguished from a primary psychotic disorder based on the aforementioned behavioral and cognitive sequelae. Preliminary evidence, on the other hand, suggests that chronic METH psychosis may be clinically similar to that of primary psychotic disorders, particularly with respect to positive and cognitive symptomatology, although negative symptoms appear to be more pronounced in schizophrenia. Limitations of the literature and avenues for future research are also discussed.

Violent offences of methamphetamine users and dilemmas of forensic psychiatric assessment

Methamphetamine (MA), an extremely addictive synthetic stimulant, has quickly spread to become the most frequently used illicit drug in China. People with a history of chronic and heavy MA use have a high possibility of exhibiting schizophrenia-like psychotic symptoms, mainly delusions of reference, auditory hallucinations and cognitive deficits. These emerging findings suggest MA use increases aggression and violence and that there is a correlation between MA use and violence. However, it is unclear how to assess the capacity of criminal responsibility in "MA-induced" psychosis and how to set clear boundaries between schizophrenia and MA-induced psychosis when only limited and inconsistent evidence is available. Furthermore, a final persuasive differential diagnostic method based on improved understanding of schizophrenia and MA-induced psychotic disorders has yet to be developed. This paper will evaluate the epidemiology, social harm, and forensic psychiatric assessment of MA users, propose a future direction for the differential diagnosis between MA-induced psychotic disorders and schizophrenia, and put forward some practical solutions to assess the capacity of criminal responsibility of defendants with drug-induced psychotic disorder.

Sigma Receptors and Substance Use Disorders

Thanks to advances in neuroscience, addiction is now recognized as a chronic brain disease with genetic, developmental, and cultural components. Drugs of abuse, including alcohol, are able to produce significant neuroplastic changes responsible for the profound disturbances shown by drug addicted individuals. The current lack of efficacious pharmacological treatments for substance use disorders has encouraged the search for novel and more effective pharmacotherapies. Growing evidence strongly suggests that Sigma Receptors are involved in the addictive and neurotoxic properties of abused drugs, including cocaine , methamphetamine , and alcohol. The present chapter will review the current scientific knowledge on the role of the Sigma Receptor system in the effects of drugs and alcohol, and proposes that this receptor system may represent a novel therapeutic target for the treatment of substance use disorders and associated neurotoxicity.

Psychosis associated with acute recreational drug toxicity: a European case series

BACKGROUND

Psychosis can be associated with acute recreational drug and novel psychoactive substance (NPS) toxicity. However, there is limited data available on how common this is and which drugs are most frequently implicated. We describe a European case series of psychosis associated with acute recreational drug toxicity, and estimate the frequency of psychosis for different recreational drugs.

METHODS

The European Drug Emergencies Network (Euro-DEN) collects data on presentations to Emergency Departments (EDs) with acute recreational drug and NPS toxicity at 16 centres in ten countries. Euro-DEN data from October 2013 through September 2014 was retrospectively searched, and cases with psychosis were included. The proportion of cases with psychosis per drug was calculated in the searched Euro-DEN dataset.

RESULTS

Psychosis was present in 348 (6.3 %) of 5529 cases. The median (interquartile range) age was 29 (24-38) years, 276 (79.3 %) were male and 114 (32.8 %) were admitted to psychiatric ward. The drugs most commonly reported were cannabis in 90 (25.9 %) cases, amphetamine in 87 (25.0 %) and cocaine in 56 (16.1 %). More than one drug was taken in 189 (54.3 %) cases. Psychosis was frequent in those ED presentations involving tryptamines (4/7; 57.1 %), methylenedioxypyrovalerone (MDPV) (6/22; 27.3 %), methylphenidate (6/26; 23.1 %), lysergic acid diethylamide (LSD) (18/86; 20.9 %), psilocybe mushrooms (3/16; 18.8 %), synthetic cannabinoid receptor agonists (4/26; 15.4 %) and amphetamine (87/593; 14.7 %), but less common in those involving mephedrone (14/245; 5.7 %), methylenedioxymethamphetamine (MDMA) (20/461; 4.3 %) and methedrone (3/92; 3.3 %). Amphetamine was the most frequent drug associated with psychosis when only one agent was reported, with psychosis occurring in 32.4 % of these presentations.

CONCLUSION

The frequency of psychosis in acute recreational drug toxicity varies considerably between drugs, but is a major problem in amphetamine poisoning. In rapidly changing drug markets and patterns of use, the Euro-DEN sentinel network contributes to measuring the scale of drug-related harms in Europe beyond other more established indicators.

Correlates of transient versus persistent psychotic symptoms among dependent methamphetamine users

This study examined correlates of transient versus persistent psychotic symptoms among people dependent on methamphetamine. A longitudinal prospective cohort study of dependent methamphetamine users who did not meet DSM-IV criteria for lifetime schizophrenia or mania. Four non-contiguous one-month observation periods were used to identify participants who had a) no psychotic symptoms, (n=110); (b) psychotic symptoms only when using methamphetamine (transient psychotic symptoms, n=85); and, (c) psychotic symptoms both when using methamphetamine and when abstaining from methamphetamine (persistent psychotic symptoms, n=37). Psychotic symptoms were defined as a score of 4 or greater on any of the Brief Psychiatric Rating Scale items of suspiciousness, hallucinations or unusual thought content. Relative no psychotic symptoms, both transient and persistent psychotic symptoms were associated with childhood conduct disorder and comorbid anxiety disorders. Earlier onset methamphetamine use and being male were more specifically related to transient psychotic symptoms, while a family history of a primary psychotic disorder and comorbid major depression were specifically related to persistent psychotic symptoms. We conclude that there are overlapping but also distinct clinical correlates of transient versus persistent psychotic symptoms, suggesting potentially heterogeneous etiological pathways underpinning the psychotic phenomena seen amongst people who use methamphetamine.

The Effect of Chronic Methamphetamine Exposure on the Hippocampal and Olfactory Bulb Neuroproteomes of Rats

Nowadays, drug abuse and addiction are serious public health problems in the USA. Methamphetamine (METH) is one of the most abused drugs and is known to cause brain damage after repeated exposure. In this paper, we conducted a neuroproteomic study to evaluate METH-induced brain protein dynamics, following a two-week chronic regimen of an escalating dose of METH exposure. Proteins were extracted from rat brain hippocampal and olfactory bulb tissues and subjected to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Both shotgun and targeted proteomic analysis were performed. Protein quantification was initially based on comparing the spectral counts between METH exposed animals and their control counterparts. Quantitative differences were further confirmed through multiple reaction monitoring (MRM) LC-MS/MS experiments. According to the quantitative results, the expression of 18 proteins (11 in the hippocampus and 7 in the olfactory bulb) underwent a significant alteration as a result of exposing rats to METH. 13 of these proteins were up-regulated after METH exposure while 5 were down-regulated. The altered proteins belonging to different structural and functional families were involved in processes such as cell death, inflammation, oxidation, and apoptosis.

Reduced Prefrontal Cortex Hemodynamic Response in Adults with Methamphetamine Induced Psychosis: Relevance for Impulsivity

Patients with methamphetamine abuse/dependence often exhibit high levels of impulsivity, which may be associated with the structural abnormalities and functional hypoactivities observed in the frontal cortex of these subjects. Although near-infrared spectroscopy (NIRS) is a simple and non-invasive method for characterizing the clinical features of various psychiatric illnesses, few studies have used NIRS to directly investigate the association between prefrontal cortical activity and inhibitory control in patients with methamphetamine-induced psychosis (MAP). Using a 24-channel NIRS system, we compared hemodynamic responses during the Stroop color-word task in 14 patients with MAP and 21 healthy controls matched for age, sex and premorbid IQ. In addition, we used the Barrett Impulsivity Scale-11 (BIS-11) to assess impulsivity between subject groups. The MAP group exhibited significantly less activation in the anterior and frontopolar prefrontal cortex accompanied by lower Stroop color-word task performance, compared with controls. Moreover, BIS-11 scores were significantly higher in the MAP group, and were negatively correlated with the hemodynamic responses in prefrontal cortex. Our data suggest that reduced hemodynamic responses in the prefrontal cortex might reflect higher levels of impulsivity in patients with MAP, providing new insights into disrupted inhibitory control observed in MAP.

The profile of psychiatric symptoms exacerbated by methamphetamine use

BACKGROUND

Methamphetamine use can produce symptoms almost indistinguishable from schizophrenia. Distinguishing between the two conditions has been hampered by the lack of a validated symptom profile for methamphetamine-induced psychiatric symptoms. We use data from a longitudinal cohort study to examine the profile of psychiatric symptoms that are acutely exacerbated by methamphetamine use.

METHODS

164 methamphetamine users, who did not meet DSM-IV criteria for a lifetime primary psychotic disorder, were followed monthly for one year to assess the relationship between days of methamphetamine use and symptom severity on the 24-item Brief Psychiatric Rating Scale. Exacerbation of psychiatric symptoms with methamphetamine use was quantified using random coefficient models. The dimensions of symptom exacerbation were examined using principal axis factoring and a latent profile analysis.

RESULTS

Symptoms exacerbated by methamphetamine loaded on three factors: positive psychotic symptoms (suspiciousness, unusual thought content, hallucinations, bizarre behavior); affective symptoms (depression, suicidality, guilt, hostility, somatic concern, self-neglect); and psychomotor symptoms (tension, excitement, distractibility, motor hyperactivity). Methamphetamine use did not significantly increase negative symptoms. Vulnerability to positive psychotic and affective symptom exacerbation was shared by 28% of participants, and this vulnerability aligned with a past year DSM-IV diagnosis of substance-induced psychosis (38% vs. 22%, χ(2)(df1)=3.66, p=0.056).

CONCLUSION

Methamphetamine use produced a symptom profile comprised of positive psychotic and affective symptoms, which aligned with a diagnosis of substance-induced psychosis, with no evidence of a negative syndrome.

Stimulant dependence and stimulant-associated psychosis: clinical characteristics and age of onset in a native American community sample

OBJECTIVES

Native Americans experience some of the highest rates of Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) stimulant dependence (SD) of all US ethnic groups. The present report examined the clinical characteristics and age of onset of stimulant use, SD, remission from SD, and stimulant-associated psychosis (SAP) in a Native American community sample.

METHODS

Demographic information, stimulant (methamphetamine or cocaine) use, and lifetime Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) psychiatric disorder diagnoses were assessed in 858 Native Americans. Logistic regression was used to assess the associations of demographic, stimulant use, and psychiatric disorder variables with SD, remission from SD, and SAP. Kaplan-Meier survival analyses were used to assess time from first use to the onset of SD.

RESULTS

The overall rate of SD was 33%, of remission from SD 73%, and of SAP 17%. Stimulant dependence was associated with older age, less current annual household income, fewer lifetime years of education, intravenous stimulant use, and earlier age of first stimulant use. Remission from SD was associated with older age, currently being married, and never having used stimulants intravenously. Attention-deficit/hyperactivity disorder (assessed as a lifetime disorder), increased number of years of daily stimulant use, and intravenous use were independently associated with SAP. Younger age at first use was significantly associated with shorter survival to the onset of SD.

CONCLUSIONS

Stimulant dependence is prevalent in this population and is associated with less income and education and an earlier age at first use. Intravenous stimulant use adds additional risk for SD, nonremission, and psychosis.

Differences in Clinical Features of Methamphetamine Users with Persistent Psychosis and Patients with Schizophrenia

BACKGROUND

Methamphetamine exerts neurotoxic effects and elicits psychotic symptoms. This study attempted to compare clinical differences between methamphetamine users with persistent psychosis (MAP) and patients with schizophrenia. In addition, we examined the discrimination validity by using symptom clusters to differentiate between MAP and schizophrenia.

METHODS

We enrolled 53 MAP patients and 53 patients with schizophrenia. The psychopathology of participants was assessed using the Chinese version of the Diagnostic Interview for Genetic Studies and the 18-item Brief Psychiatric Rating Scale. Logistic regression was used to examine the predicted probability scores of different symptom combinations on discriminating between MAP and schizophrenia. The receiver operating characteristic (ROC) analyses and area under the curve (AUC) were further applied to examine the discrimination validity of the predicted probability scores on differentiating between MAP and schizophrenia.

RESULTS

We found that MAP and schizophrenia demonstrated similar patterns of delusions. Compared to patients with schizophrenia, MAP experienced significantly higher proportions of visual hallucinations and of somatic or tactile hallucinations. However, MAP exhibited significantly lower severity in conceptual disorganization, mannerism/posturing, blunted affect, emotional withdrawal, and motor retardation compared to patients with schizophrenia. The ROC analysis showed that a predicted probability score combining the aforementioned 7 items of symptoms could significantly differentiate between MAP and schizophrenia (AUC = 0.77).

CONCLUSION

Findings in the current study suggest that nuanced differences might exist in the clinical presentation of secondary psychosis (MAP) and primary psychosis (schizophrenia). Combining the symptoms as a whole may help with differential diagnosis for MAP and schizophrenia.

Neuropsychiatric Adverse Effects of Amphetamine and Methamphetamine

Administration of amphetamine and methamphetamine can elicit psychiatric adverse effects at acute administration, binge use, withdrawal, and chronic use. Most troublesome of these are psychotic states and aggressive behavior, but a large variety of undesirable changes in cognition and affect can be induced. Adverse effects occur more frequently with higher dosages and long-term use. They can subside over time but some persist long-term. Multiple alterations in the gray and white matter of the brain assessed as changes in tissue volume or metabolism, or at molecular level, have been associated with amphetamine and methamphetamine use and the psychiatric adverse effects, but further studies are required to clarify their causal role, specificity, and relationship with preceding states and traits and comorbidities. The latter include other substance use disorders, mood and anxiety disorders, attention deficit hyperactivity disorder, and antisocial personality disorder. Amphetamine- and methamphetamine-related psychosis is similar to schizophrenia in terms of symptomatology and pathogenesis, and these two disorders share predisposing genetic factors.

Neurologic Complications of Psychomotor Stimulant Abuse

Psychomotor stimulants are drugs that act on the central nervous system (CNS) to increase alertness, elevate mood, and produce a sense of well-being. These drugs also decrease appetite and the need for sleep. Stimulants can enhance stamina and improve performance in tasks that have been impaired by fatigue or boredom. Approved therapeutic applications of stimulants include attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. These agents also possess potent reinforcing properties that can result in excessive self-administration and abuse. Chronic use is associated with adverse effects including psychosis, seizures, and cerebrovascular accidents, though these complications usually occur in individuals with preexisting risk factors. This chapter reviews the adverse neurologic consequences of chronic psychomotor stimulant use and abuse, with a focus on two prototypical stimulants methamphetamine and cocaine.

Methamphetamine psychosis: epidemiology and management

Psychotic symptoms and syndromes are frequently experienced among individuals who use methamphetamine, with recent estimates of up to approximately 40 % of users affected. Although transient in a large proportion of users, acute symptoms can include agitation, violence, and delusions, and may require management in an inpatient psychiatric or other crisis intervention setting. In a subset of individuals, psychosis can recur and persist and may be difficult to distinguish from a primary psychotic disorder such as schizophrenia. Differential diagnosis of primary vs. substance-induced psychotic disorders among methamphetamine users is challenging; nevertheless, with careful assessment of the temporal relationship of symptoms to methamphetamine use, aided by state-of-the art psychodiagnostic assessment instruments and use of objective indicators of recent substance use (i.e., urine toxicology assays), coupled with collateral clinical data gathered from the family or others close to the individual, diagnostic accuracy can be optimized and the individual can be appropriately matched to a plan of treatment. The pharmacological treatment of acute methamphetamine-induced psychosis may include the use of antipsychotic medications as well as benzodiazepines, although symptoms may resolve without pharmacological treatment if the user is able to achieve a period of abstinence from methamphetamine. Importantly, psychosocial treatment for methamphetamine dependence has a strong evidence base and is the optimal first-line treatment approach to reducing rates of psychosis among individuals who use methamphetamines. Prevention of methamphetamine relapse is the most direct means of preventing recurrence of psychotic symptoms and syndromes. Long-term management of individuals presenting with recurrent and persistent psychosis, even in the absence of methamphetamine use, may include both behavioral treatment to prevent resumption of methamphetamine use and pharmacological treatment targeting psychotic symptoms. In addition, treatment of co-occurring psychiatric disorders including depression and anxiety is important as a means of preventing relapse to methamphetamine use, which is often triggered by associated symptoms.

The neurobiology of methamphetamine induced psychosis

Chronic methamphetamine abuse commonly leads to psychosis, with positive and cognitive symptoms that are similar to those of schizophrenia. Methamphetamine induced psychosis (MAP) can persist and diagnoses of MAP often change to a diagnosis of schizophrenia over time. Studies in schizophrenia have found much evidence of cortical GABAergic dysfunction. Methamphetamine psychosis is a well studied model for schizophrenia, however there is little research on the effects of methamphetamine on cortical GABAergic function in the model, and the neurobiology of MAP is unknown. This paper reviews the effects of methamphetamine on dopaminergic pathways, with focus on its ability to increase glutamate release in the cortex. Excess cortical glutamate would likely damage GABAergic interneurons, and evidence of this disturbance as a result of methamphetamine treatment will be discussed. We propose that cortical GABAergic interneurons are particularly vulnerable to glutamate overflow as a result of subcellular location of NMDA receptors on interneurons in the cortex. Damage to cortical GABAergic function would lead to dysregulation of cortical signals, resulting in psychosis, and further support MAP as a model for schizophrenia.

(1)H-magnetic resonance spectroscopy ((1)H-MRS) in methamphetamine dependence and methamphetamine induced psychosis

BACKGROUND

Methamphetamine (MA) use has been shown to decrease n-acetyl-aspartate (NAA), a marker of neuronal integrity and viability, on (1)H magnetic resonance spectroscopy ((1)H-MRS). However, little work has compared (1)H-MRS in MA dependent individuals and MA dependent individuals with MA induced psychotic disorder (MAP).

METHODS

Twenty six participants with MA dependence (sixteen without psychosis, ten with psychosis - MAP) and nineteen healthy controls underwent 2D-chemical shift imaging (1)H-MRS, which included voxels in the anterior cingulate cortices (ACC), dorsolateral prefrontal cortices (DLPFC), and frontal white matter. We compared metabolite concentrations relative to phosphocreatine+creatine (PCr+Cr) for n-acetyl-aspartate (NAA), n-acetyl-aspartate+n-acetyl-aspartyl-glutamate (NAA+NAAG), glutamate (Glu), glutamate+glutamine (Glu+Gln), myo-inositol, and glycerophosphocholine+phosphocholine (GPC+PCh) across groups.

RESULTS

The MA groups showed significantly decreased relative NAA metabolite concentrations for right ACC and right DLPFC, compared with control group. The MA dependent group only showed significantly decreased choline metabolites for right DLPFC, compared with control group. The MAP group's relative NAA metabolite concentrations were significantly correlated with age of initial use and duration of MA use, these correlates were not apparent in MA dependent group.

CONCLUSION

MA use is associated with decreased neuronal integrity and viability, specifically in the right ACC and right DLPFC. MA dependence showed active neurodegeneration in the right DLPFC, this was not apparent in the MAP group and may be related to the use of antipsychotic medication in the MAP group. The effects of MA use in MAP suggest that age of initial use presents a mismatch of neuronal plasticity, in frontal white vs. gray matter and duration of use relates to decreased neuronal integrity and viability. Further study is warranted from this initial study of (1)H-MRS in MAP, in particular longitudinal assessment of these individuals both neurobiologically ((1)H-MRS) and clinically - to determine disease progression.

Current research on the epidemiology, medical and psychiatric effects, and treatment of methamphetamine use

Methamphetamine (MA) is a drug that is widely used in many parts of the world. It has multiple neurobiological impacts on the nervous system, some of which are transitory and some more long lasting. MA activates the reward system of the brain and produces effects that are highly reinforcing, which can lead to abuse and dependence. Routes of administration that produce rapid onset of the drug's effects (i.e., smoking and injection) are likely to lead to more rapid addiction and more medical and psychiatric effects. The medical effects of MA use are extensive, and chronic use of MA can produce significant neurological damage as well as damage to cardiovascular, pulmonary, and other organ systems. Both acute and chronic MA use can lead to extreme paranoia, anxiety, and depression, and following discontinuation of MA use, cognitive deficits and anhedonia can persist for months. No effective pharmacotherapies have been developed for the treatment of MA dependence, although this is an area of very active research. Several behavioral treatments have been shown to reduce MA use, but better treatments are needed. The research agenda for MA is substantial, with development of effective pharmacotherapies as one of the most important priorities.

Health conditions in methamphetamine-dependent adults 3 years after treatment

OBJECTIVES

: Medical conditions in methamphetamine (MA) users have not been well characterized. Using both self-report and physical examination data, the aims of this study were to (1) describe the frequency of medical conditions in a sample of MA users 3 years posttreatment; (2) evaluate the association between medical conditions and MA use frequency; and (3) examine the relationship of route of administration with medical outcomes.

METHODS

: MA-dependent adults (N = 301) who participated in the Methamphetamine Treatment Project were interviewed and examined 3 years after treatment. Medical, demographic, and substance use characteristics were assessed using the Addiction Severity Index and Life Experiences Timeline. Current and lifetime medical conditions, electrocardiogram characteristics, and physical examination abnormalities were assessed.

RESULTS

: Among the most frequently reported lifetime conditions were wounds and burns (40.5%, N = 122) and severe dental problems (33%, N = 99), and a significant proportion of the sample evidenced prolonged corrected QT interval (19.6%, N = 43). Although health conditions were not associated with MA use frequency during follow-up, intravenous MA use was significantly associated with missing teeth (odds ratio = 2.4; 95% confidence interval, 1.2-4.7) and hepatitis C antibodies (odds ratio = 13.1; confidence interval, 5.6-30.1).

CONCLUSION

: In this sample of MA users, dental problems and corrected QT prolongation were observed at elevated rates. Although posttreatment MA use frequency was not associated with a majority of medical outcomes, intravenous MA use exacerbated risk for dental pathology and hepatitis C. Longer term follow-up research is needed to elucidate health trajectories of MA users.

Neurologic manifestations of chronic methamphetamine abuse

The drug with perhaps the greatest impact on the practice of Psychiatry is Methamphetamine. By increasing the extracellular concentrations of dopamine while slowly damaging the dopaminergic neurotransmission, Meth is a powerfully addictive drug whose chronic use preferentially causes psychiatric complications. Chronic Meth users have deficits in memory and executive functioning as well as higher rates of anxiety, depression, and most notably psychosis. It is because of addiction and chronic psychosis from Meth abuse that the Meth user is most likely to come to the attention of the practicing Psychiatrist/Psychologist. Understanding the chronic neurologic manifestations of Meth abuse will better arm practitioners with the diagnostic and therapeutic tools needed to make the Meth epidemic one of historical interest only.

Methamphetamine use: a comprehensive review of molecular, preclinical and clinical findings

Methamphetamine (MA) is a highly addictive psychostimulant drug that principally affects the monoamine neurotransmitter systems of the brain and results in feelings of alertness, increased energy and euphoria. The drug is particularly popular with young adults, due to its wide availability, relatively low cost, and long duration of psychoactive effects. Extended use of MA is associated with many health problems that are not limited to the central nervous system, and contribute to increased morbidity and mortality in drug users. Numerous studies, using complementary techniques, have provided evidence that chronic MA use is associated with substantial neurotoxicity and cognitive impairment. These pathological effects of the drug, combined with the addictive properties of MA, contribute to a spectrum of psychosocial issues that include medical and legal problems, at-risk behaviors and high societal costs, such as public health consequences, loss of family support and housing instability. Treatment options include pharmacological, psychological or combination therapies. The present review summarizes the key findings in the literature spanning from molecular through to clinical effects.

Methamphetamine-related psychiatric visits to an urban academic emergency department: an observational study

BACKGROUND

Methamphetamine, a stimulant of abuse, is associated with a significant number of Emergency Department (ED) visits. Methamphetamine use may produce psychiatric symptoms including acute psychosis, depression, and anxiety disorders.

STUDY OBJECTIVES

To characterize psychiatric emergencies either directly or indirectly attributable to methamphetamine use in an urban academic ED.

METHODS

We analyzed a database of patients determined to have an ED visit that was either methamphetamine related or non-methamphetamine related. We retrospectively reviewed the records of the subset of ED visits from this database with psychiatric diagnoses. We compared the characteristics of patients with methamphetamine-related psychiatric visits (MRPVs) and non-methamphetamine-related psychiatric visits (non-MRPVs).

RESULTS

We identified 130 patients with MRPVs. This represented 7.6% (130 of 1709) of all psychiatric visits. Patients with MRPV, compared to non-MRPV patients, were younger (34.4 years vs. 39.1 years, respectively, p = 0.0005), more likely to be uninsured (55% vs. 37%, respectively, p = 0.001), and less likely to have a past history of depression (10% vs. 19%, respectively, p = 0.011). Many characteristics between the two groups (MRPV vs. non-MRPV) were similar: likelihood of patient being placed on a psychiatric hold; hospital charges; previous histories of psychiatric visits; and history of anxiety, bipolar disorder, or schizophrenia.

CONCLUSIONS

Methamphetamine may be related to a significant proportion (7.6%) of psychiatric ED visits. Furthermore, patients with methamphetamine-associated psychiatric visits are younger, have lower rates of depression, are more likely to be uninsured, and are less likely to have a substance abuse-related chief complaint than patients with non-methamphetamine-associated ED psychiatric visits.

Clinical features of inpatients with methamphetamine-induced psychosis

BACKGROUND

An epidemic of methamphetamine use has begun in Iran in recent years and psychiatric emergency services are overloaded with patients with methamphetamine-induced psychosis (MIP).

AIMS

To define the clinical features of inpatients with MIP in a psychiatric hospital.

METHOD

The files of all MIP patients admitted to Iran Psychiatric Hospital located in Tehran from April 2008 to April 2010 were assessed. Data related to psychotic episode, substance use, previous psychiatric history and demographic data of 111 MIP patients were extracted and analyzed using descriptive statistical methods.

RESULTS

The most prevalent psychotic symptoms were persecutory delusion (82%), auditory hallucination (70.3%), reference delusion (57.7%), visual hallucination (44.1%), grandiosity delusion (39.6%) and jealousy delusion (26.1%). The mean duration of admission and psychotic episode was 21.43 and 17.37 days, respectively. In seven cases (8.75%), symptoms continued for more than one month.

CONCLUSION

Frequency of psychotic symptoms in this study is relatively similar to previous studies. However, some clinical determinants such as latency of psychosis from first use and the course of psychosis are more similar to the first epidemic of methamphetamine in Japan than to more recent epidemics; which could be due to the short history of methamphetamine use in Iran.

Methamphetamine-associated psychosis

Methamphetamine (METH) is a frequent drug of abuse in U.S. populations and commonly associated with psychosis. This may be a factor in frequent criminal justice referrals and lengthy treatment required by METH users. Persecutory delusions and auditory hallucinations are the most consistent symptoms of METH-associated psychosis (MAP). MAP has largely been studied in Asian populations and risk factors have varied across studies. Duration, frequency and amount of use as well as sexual abuse, family history, other substance use, and co-occurring personality and mood disorders are risk factors for MAP. MAP may be unique with its long duration of psychosis and recurrence without relapse to METH. Seven candidate genes have been identified that may be associated with MAP. Six of these genes are also associated with susceptibility, symptoms, or treatment of schizophrenia and most are linked to glutamatergic neurotransmission. Animal studies of pre-pulse inhibition, attenuation of social interaction, and stereotypy and alterations in locomotion are used to study MAP in rodents. Employing various models, rodent studies have identified neuroanatomical and neurochemical changes associated with METH use. Throughout this review, we identify key gaps in our understanding of MAP and suggest potential directions for future research.

Neurologic manifestations of chronic methamphetamine abuse

Methamphetamine abuse has reached epidemic proportions in the United States. The repetitive use of methamphetamine causes massive and sustained elevations in central monoamines. These elevations, particularly in dopamine, can cause changes in the function of the central nervous system that can manifest as a variety of neurologic disorders. This article focuses on these disorders, such as neurocognitive disorders and mental illness, including drug-induced psychosis; motor disorders, including the possible risk of Parkinson's disease, the development of choreoathetoid movements, and punding; and changes in the physical appearance of the methamphetamine users, including dental caries.

Long-term outcomes in methamphetamine psychosis patients after first hospitalisation

INTRODUCTION AND AIMS

As a consequence of the methamphetamine epidemic in Thailand, the occurrence of methamphetamine psychosis (MAP) dramatically increased. This study aimed to examine the long-term outcomes of MAP patients following their first presentation to a psychiatric hospital.

DESIGN AND METHODS

Methamphetamine psychosis patients who were first hospitalised in Suan Prung psychiatric hospital Thailand in 2000-2001 were identified through a review of the hospital database. Eligible participants were scheduled for visits by trained field researchers in 2007. For those giving consent, a structured face-to-face interview was conducted. Outcomes were collected from both medical records and interviews.

RESULTS

A total of 1116 participants were included in the study. Ninety-two (8.2%) participants had died from suicide, accident or AIDS. Due to relocation, only 449 (40.2%) individuals were interviewed. Most of the participants were male (90.6%) with a mean age of 33.3 years (SD = 8.0). The medical records showed that 263 had revisited the hospital in the interim. Of those, 39.2% were re-hospitalised and 38% were given a diagnosis of schizophrenia due to persistent psychosis. The outreach interview found that more than half (55.7%) had experienced psychosis relapse. Mini International Neuropsychiatric Interview revealed the following current conditions: psychotic disorders (15.8%), alcohol use disorders (52.1%) and suicidality (22.3%). Participants who did not have a diagnosis of current methamphetamine abuse could be divided into those with a single episode psychosis (52.6%) and those with chronic course of psychosis (38.8%).

DISCUSSION AND CONCLUSIONS

Individuals with MAP are likely to have poor outcomes, in terms of premature death, several relapses of psychotic symptoms, chronic psychotic manifestation, and very rates of alcohol use disorder and suicidality. Therefore, those individuals with MAP require long-term monitoring and psychiatric care.

Relationship between gender and psychotic symptoms in cocaine-dependent and methamphetamine-dependent participants

BACKGROUND

It has been well documented that cocaine and methamphetamine use can lead to the onset of psychotic symptoms similar to schizophrenia. However, the research and literature on gender differences and stimulant-induced psychosis have been mixed.

OBJECTIVE

The primary aim of this study was to investigate gender differences in the reporting of psychotic symptoms in cocaine- versus methamphetamine-dependent individuals.

METHODS

Participants were recruited from the Los Angeles, California, community via radio and newspaper advertisements. All met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for cocaine or methamphetamine dependence, and all reported either methamphetamine or cocaine as their primary drug of abuse. During a screening interview, participants answered questions from the Psychotic Symptom Assessment Scale, which characterizes various types of psychotic symptoms during drug use ("while high") or during periods of nonuse ("while abstinent").

RESULTS

Participants included 42 cocaine-dependent individuals (27 men, 15 women) and 43 methamphetamine-dependent individuals (25 men, 18 women). Among cocaine users, there were no significant differences between men and women with regard to ethnicity, years of use, route of administration, and amount used in the past week, though they differed significantly with regard to age (P = 0.029). In the "while abstinent" condition, women were significantly more likely than men to report experiencing auditory hallucinations (13% vs 0%, respectively; P = 0.050) and tactile hallucinations (20% vs 0%; P = 0.016), whereas men were more likely to report delusions of grandeur (48% vs 6%; P = 0.006). During the "while high" condition, women were significantly more likely than men to report delusions of grandeur (13% vs 0%, respectively; P = 0.050), tactile hallucinations (33% vs 0%; P = 0.001), and olfactory hallucinations (13% vs 0%; P = 0.050). Among methamphetamine users, there were no significant differences between men and women with regard to age, ethnicity, years of use, route of administration, or amount used in the past week. In the "while abstinent" condition, women were significantly more likely than men to report feeling that something was wrong with the way a part of their body looked (72% vs 32%, respectively; P = 0.009), olfactory hallucinations (39% vs 8%; P = 0.010) and dressing inappropriately (22% vs 0%; P = 0.010). During the "while high" condition, women were more likely than men to report delusions of grandeur (33% vs 16%, respectively; P = 0.030), paranoia (50% vs 16%; P = 0.017), and tactile hallucinations (61% vs 32%; P = 0.050).

CONCLUSIONS

The findings of the present study revealed that cocaine- and methamphetamine-dependent women were more likely than their male counterparts to report experiencing various psychotic symptoms. This information may be useful for clinicians and mental health professionals, who should take these symptoms into account as potential barriers that may impede effective treatment.

Khat use and neurobehavioral functions: suggestions for future studies

Although there is a rich body of research available regarding the effect of acute and chronic khat dosing in animal models, research on the behavioral and cognitive effects of khat in human subjects is not extensive and several of the available studies have been done only in the context of observational and single-case studies. In light of the absence of a substantial literature on the neurobehavioral deficits associated with khat use and to provide a context that could be used to identify themes for future research we review previous research that has focused on other stimulant drugs. This review highlights multiple areas of neurocognitive deficit that have been identified in previous studies of individuals who have been chronic users of stimulants, such as amphetamines and methamphetamines. The review highlights a substantial body of evidence demonstrating a wide range of learning and memory impairments including deficits that persist during abstinence from active drug use. This review does not imply a similar khat effect, but due to some similarities pharmacologically between the active components of khat (cathinone and cathine) and amphetamines, future studies examining these same domains of cognitive functioning in chronic khat users and abstinent khat users appears to be warranted, if possible using some of the same or similar laboratory measures.

The clinical toxicology of metamfetamine

INTRODUCTION

Metamfetamine is a highly addictive amfetamine analog that acts primarily as a central nervous system (CNS) stimulant. The escalating abuse of this drug in recent years has lead to an increasing burden upon health care providers. An understanding of the drug's toxic effects and their medical treatment is therefore essential for the successful management of patients suffering this form of intoxication.

AIM

The aim of this review is to summarize all main aspects of metamfetamine poisoning including epidemiology, mechanisms of toxicity, toxicokinetics, clinical features, diagnosis, and management.

METHODS

A summary of the literature on metamfetamine was compiled by systematically searching OVID MEDLINE and ISI Web of Science. Further information was obtained from book chapters, relevant news reports, and web material. Epidemiology. Following its use in the Second World War, metamfetamine gained popularity as an illicit drug in Japan and later the United States. Its manufacture and use has now spread to include East and South-East Asia, North America, Mexico, and Australasia, and its world-wide usage, when combined with amfetamine, exceeds that of all other drugs of abuse except cannabis. Mechanisms of toxicity. Metamfetamine acts principally by stimulating the enhanced release of catecholamines from sympathetic nerve terminals, particularly of dopamine in the mesolimbic, mesocortical, and nigrostriatal pathways. The consequent elevation of intra-synaptic monoamines results in an increased activation of central and peripheral α±- and β-adrenergic postsynaptic receptors. This can cause detrimental neuropsychological, cardiovascular, and other systemic effects, and, following long-term abuse, neuronal apoptosis and nerve terminal degeneration. Toxicokinetics. Metamfetamine is rapidly absorbed and well distributed throughout the body, with extensive distribution across high lipid content tissues such as the blood-brain barrier. In humans the major metabolic pathways are aromatic hydroxylation producing 4-hydroxymetamfetamine and N-demethylation to form amfetamine. Metamfetamine is excreted predominantly in the urine and to a lesser extent by sweating and fecal excretion, with reported terminal half-lives ranging from ∼5 to 30 h. Clinical features. The clinical effects of metamfetamine poisoning can vary widely, depending on dose, route, duration, and frequency of use. They are predominantly characteristic of an acute sympathomimetic toxidrome. Common features reported include tachycardia, hypertension, chest pain, various cardiac dysrhythmias, vasculitis, headache, cerebral hemorrhage, hyperthermia, tachypnea, and violent and aggressive behaviour. Management. Emergency stabilization of vital functions and supportive care is essential. Benzodiazepines alone may adequately relieve agitation, hypertension, tachycardia, psychosis, and seizure, though other specific therapies can also be required for sympathomimetic effects and their associated complications.

CONCLUSION

Metamfetamine may cause severe sympathomimetic effects in the intoxicated patient. However, with appropriate, symptom-directed supportive care, patients can be expected to make a full recovery.

Methamphetamine and paranoia: the methamphetamine experience questionnaire

Paranoia in methamphetamine (MA) users is not well characterized or understood. To investigate this phenomenon, we created the Methamphetamine Experience Questionnaire (MEQ), and tested its reliability and validity in assessing MA-induced paranoia. We administered the MEQ to 274 MA-dependent subjects. Of the total subjects, 45% (123) first experienced paranoia with MA use; 55% did not. Obtaining or using a weapon while paranoid was common (37% and 11% of subjects with MA-induced paranoia, respectively). Test-retest and inter-rater reliability for MA-induced paranoia showed substantial agreement (kappa = .77, p < .05 and kappa = .80, p < .05, respectively). First episodes of paranoia occurred more often with intravenous use of MA, and subsequent episodes at higher doses. There was modest correlation between paranoia on the MEQ and the Brief Symptom Inventory (BSI) paranoid ideation scale (rho = .27, p < .05). As expected, there was a poor correlation between paranoia on the MEQ and the BSI depression scale (rho = .14, p = .07). The MEQ provides useful information on drug use variables that contribute to paranoia commonly associated with MA use. (Am J Addict 2010;00:1-14).

The methamphetamine problem in the United States

Significant public health problems associated with methamphetamine (MA) production and use in the United States have emerged over the past 25 years; however, there has been considerable controversy about the size of the problem. Epidemiological indicators have provided a mixed picture. National surveys of the adult U.S. population and school-based populations have consistently been used to support the position that MA use is a relatively minor concern. However, many other data sources, including law-enforcement groups, welfare agencies, substance abuse treatment program admissions, criminal justice agencies, and state/county executives indicate that MA is a very significant public health problem for many communities throughout much of the country. In this article, we describe (a) the historical underpinnings of the MA problem, (b) epidemiological trends in MA use, (c) key subgroups at risk for MA problems, (d) the health and social factors associated with MA use, (e) interventions available for addressing the MA problem, and (f) lessons learned from past efforts addressing the MA problem.

An association study of monoamine oxidase A (MAOA) gene polymorphism in methamphetamine psychosis

Methamphetamine continues to be the most widely abused drug in Japan. Chronic methamphetamine users show psychiatric signs, including methamphetamine psychosis. Monoamine oxidase A (MAOA) is one of the major enzymes responsible for the degradation of neurotransmitters. Abnormalities in MAO levels have been related to a wide range of psychiatric disorders. We examined whether or not the MAOA-u variable-number tandem repeat (VNTR) has a functional polymorphism in methamphetamine psychosis and whether or not such a polymorphism is related to the prolongation of psychosis. As expected, there was a significant difference in the MAOA-u VNTR between males with persistent versus transient methamphetamine psychosis (p=0.018, odds ratio (OR)=2.76, 95% CI: 1.18-6.46). Our results suggest that the high-activity allele class of MAOA-u VNTR in males may be involved in susceptibility to a persistent course of methamphetamine psychosis. We found no differences among females. The sample size of females with methamphetamine psychosis was too small to have significant analysis.

Pharmacotherapy of methamphetamine addiction: an update

Methamphetamine dependence is a serious public health problem worldwide for which there are no approved pharmacological treatments. Psychotherapy is still the mainstay of treatment; however, relapse rates are high. The search for effective pharmacological treatment has intensified in the last decade. This review will highlight progress in pharmacological interventions to treat methamphetamine dependence as well as explore new pharmacological targets. Published data from clinical trials for stimulant addiction were searched using PubMed and summarized, as well as highlights from a recent symposium on methamphetamine pharmacotherapy presented at the ISAM 2006 meeting, including interim analysis data from an ongoing D-amphetamine study in Australia. Early pilot data are encouraging for administering D-amphetamine and methylphenidate as treatment for heavy amphetamine users. Abilify at 15 mg/day dose increased amphetamine use in an outpatient pilot study. Sertraline, ondansetron, baclofen, tyrosine, and imipramine were ineffective in proof-of-concept studies. Development of pharmacotherapy for methamphetamine dependence is still in an early stage. Data suggesting D-amphetamine and methylphenidate as effective pharmacotherapy for methamphetamine addiction will need to be confirmed by larger trials. Preclinical data suggest that use of GVG, CB1 antagonist, and lobeline are also promising therapeutic strategies.