An Overview of Methamphetamine-induced Psychotic Syndromes

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.

The neurocircuitry involved in oxytocin modulation of methamphetamine addiction

The role of oxytocin in attenuating the abuse of licit and illicit drugs, including the psychostimulant methamphetamine, has been examined with increased ferocity in recent years. This is largely driven by the potential application of oxytocin as a pharmacotherapy. However, the neural mechanisms by which oxytocin modulates methamphetamine abuse are not well understood. Recent research identified an important role for the accumbens core and subthalamic nucleus in this process, which likely involves an interaction with dopamine, glutamate, GABA, and vasopressin. In addition to providing an overview of methamphetamine, the endogenous oxytocin system, and the effects of exogenous oxytocin on drug abuse, we propose a neural circuit through which exogenous oxytocin modulates methamphetamine abuse, focusing on its interaction with neurochemicals within the accumbens core and subthalamic nucleus. A growing understanding of exogenous oxytocin effects at a neurochemical and neurobiological level will assist in its evaluation as a pharmacotherapy for drug addiction.

Factors affecting severity of positive and negative symptoms of psychosis in a polysubstance using population with psychostimulant dependence

Approximately half of psychostimulant users experience psychotic symptoms, which include both positive and negative symptoms. Prior reports have exclusively used positive symptoms to characterize psychostimulant associated psychosis. Symptoms vary dramatically in severity, though most investigations categorize psychosis as a dichotomous occurrence. To explore the association between different substances of abuse and the severity of psychotic symptoms, we investigated 171 individuals meeting DSM-IV-TR criteria for psychostimulant (cocaine or methamphetamine) dependence in an observational cross-sectional study. Participants were predominantly male (72.5%), recruited from a socially disadvantaged neighborhood in Vancouver, Canada, with a mean age of 45.5(±8.8) years. Of the total sample, 85% were dependent on cocaine, and 28.1% were dependent on methamphetamine. Participants had a median total PANSS score of 63, ranging from 37 to 111. Demographic information, current substance use and early substance exposure were used to predict positive and negative psychotic symptom severity in linear regression models. Increased severity of positive psychotic symptoms was significantly related to greater methamphetamine and marijuana use in the past 28 days, and methadone-abstinence. Negative symptom severity was related to increased opioid use in the past 28 days. There was no overlap between predictors of positive and negative symptom severity.

Does the pattern of amphetamine use prior to incarceration predict later psychosis?--a longitudinal study of amphetamine users in the Swedish criminal justice system

OBJECTIVES

The aim of this longitudinal study was to investigate the relationship between self-reported amphetamine use prior to inclusion in the criminal justice system and hospitalization due to psychosis in the years following release.

METHOD

All the information was extracted from existing databases. Amphetamine-using clients in the criminal justice system in Sweden were identified using the European version of the addiction severity index (Europ-ASI) interview. Between 2001 and 2006, a total of 1709 individuals were identified. A follow-up of the subjects, using national registry data, was conducted in 2010. The outcome measure was hospitalization for primary or substance-induced psychotic episodes during the follow-up period. Data was analyzed in a multivariate logistic regression model.

RESULTS

Age of onset of amphetamine use, number of years used, and use in the month prior to baseline interview were all unrelated to risk of future hospitalization due to psychosis. Prior psychiatric hospitalization and experience of hallucinations not related to drug use, as well as being born outside of a Nordic country and being homeless, were all positively linked to hospitalization due to psychosis.

CONCLUSIONS

This study demonstrates that, in a cohort of amphetamine users within the criminal justice system, prior psychiatric morbidity and demographic risk factors are more important than baseline patterns of amphetamine use in predicting future risk of hospitalization due to psychosis.

Methamphetamine enhances the development of schizophrenia in first-degree relatives of patients with schizophrenia

OBJECTIVE

Although there is some evidence that methamphetamine (MA) abuse may play a causative role in the development of schizophrenia, studies directly linking these 2 are rare.

METHODS

In our study, the effect of MA abuse on the development of schizophrenia was investigated in 15 MA abusers who are offspring of patients with schizophrenia and 15 siblings of MA abusers without a history of drug abuse. Cognitive deficits and resting-state brain function were evaluated in all participants. Correlations between cognitive deficits and schizophrenia development were investigated.

RESULTS

Significantly more cognitive impairments were observed in MA abusers, compared with their siblings without a history of drug use. Significant abnormalities in regional homogeneity (ReHo) signals were observed in resting brain in MA abusers. Decreased ReHo was found to be distributed over the bilateral cingulate gyrus, right Brodmann area 24, and bilateral anterior cingulate cortex. Seven MA abusers were diagnosed with schizophrenia, while 1 control sibling was diagnosed with schizophrenia during the 5-year follow-up. The cognitive scores correlated with the development of schizophrenia in MA abusers.

CONCLUSION

Our study provides direct evidence for the causative role of MA use in the etiology of schizophrenia and highlights the role of MA-induced brain abnormalities in cognitive deficiency and development of schizophrenia.

Factors associated with involuntary admissions among patients with substance use disorders and comorbidity: a cross-sectional study

Background

To investigate factors associated with involuntary admissions to hospital pursuant to a social services act of patients with substance use disorder by comparing the socio-demographic characteristics, substance use, and psychiatric comorbidities with voluntarily admitted patients.

Methods

This cross-sectional study compared two groups admitted to combined substance use disorder and psychiatry wards. Sixty-five patients were involuntarily admitted pursuant to the Social Services Act and 137 were voluntarily admitted. The International Classification of Diseases and Related Health Problems was used for diagnostic purposes regarding substance use disorders, type and severity of psychiatric problems, and level of functioning. Socio-demographic variables were measured using the European Addiction Severity Index, and the Symptom Checklist-90-R instruments were used to evaluate the range of psychological problems and psychopathological symptoms. Logistic regression was performed to investigate the relationship between involuntary admissions and patients characteristics.

Results

Patients who had been involuntarily admitted were more likely to be females, had utilized public welfare services more often, presented more severe substance use patterns, and had a history of more frequent visits to physicians for somatic complaints in the last 6 months, they also had fewer comorbid mental disorders. Still, considerable burdens of comorbid substance use disorders and mental disorders were observed both among involuntary and voluntary admitted patients.

Conclusions

More attention is required for involuntarily admitted patients in order to meet the needs associated with complex and mixed disorders. In addition, treatment centers should offer diagnostic options and therapy regarding substance use, psychiatric and somatic disorders.

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.

Comparisons of methamphetamine psychotic and schizophrenic symptoms: a differential item functioning analysis

The concept of negative symptoms in methamphetamine (MA) psychosis (e.g., poverty of speech, flatten affect, and loss of drive) is still uncertain. This study aimed to use differential item functioning (DIF) statistical techniques to differentiate the severity of psychotic symptoms between MA psychotic and schizophrenic patients. Data of MA psychotic and schizophrenic patients were those of the participants in the WHO Multi-Site Project on Methamphetamine-Induced Psychosis (or WHO-MAIP study) and the Risperidone Long-Acting Injection in Thai Schizophrenic Patients (or RLAI-Thai study), respectively. To confirm the unidimensionality of psychotic syndromes, we applied the exploratory and confirmatory factor analyses (EFA and CFA) on the eight items of Manchester scale. We conducted the DIF analysis of psychotic symptoms observed in both groups by using nonparametric kernel-smoothing techniques of item response theory. A DIF composite index of 0.30 or greater indicated the difference of symptom severity. The analyses included the data of 168 MA psychotic participants and the baseline data of 169 schizophrenic patients. For both data sets, the EFA and CFA suggested a three-factor model of the psychotic symptoms, including negative syndrome (poverty of speech, psychomotor retardation and flatten/incongruous affect), positive syndrome (delusions, hallucinations and incoherent speech) and anxiety/depression syndrome (anxiety and depression). The DIF composite indexes comparing the severity differences of all eight psychotic symptoms were lower than 0.3. The results suggest that, at the same level of syndrome severity (i.e., negative, positive, and anxiety/depression syndromes), the severity of psychotic symptoms, including the negative ones, observed in MA psychotic and schizophrenic patients are almost the same.

Drug abuse in plastic surgery patients: optimizing detection and minimizing complications

Drugs of abuse present numerous challenges to plastic surgeons, and detection remains difficult. With rates of drug abuse and misuse on the rise, clinicians must remain especially attentive to drug abusers' verbal and nonverbal cues, and be familiar with treating perioperative complications if they arise. Informed deductions regarding drug abuse can enable a plastic surgeon to identify drug abuse, minimize complications, and optimize patient care.