title: The profile of psychiatric symptoms exacerbated by methamphetamine use.
abstract: 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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: National Drug Research Institute, Faculty of Health Sciences, Curtin University, Perth, Australia; National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia; Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, Australian National University, Canberra, Australia. Electronic address: rebecca.mcketin@curtin.edu.au.
authors.forename: Rebecca
authors.initials: R
authors.lastname: McKetin
authors.affiliation: School of Applied Psychology ​and Menzies Health Institute Queensland, Griffith University, Brisbane, Queensland, Australia.
authors.forename: Sharon
authors.initials: S
authors.lastname: Dawe
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Burns
authors.affiliation: Centre for Youth Substance Abuse Research, School of Psychology and Counselling, and Institute of Health & Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia.
authors.forename: Leanne
authors.initials: L
authors.lastname: Hides
authors.affiliation: Centre for Youth Substance Abuse Research, School of Psychology and Counselling, and Institute of Health & Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Kavanagh
authors.affiliation: National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia.
authors.forename: Maree
authors.initials: M
authors.lastname: Teesson
authors.affiliation: Centre for Youth Substance Abuse Research, School of Psychology and Counselling, and Institute of Health & Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia.
authors.forename: Ross
authors.initials: R
authors.lastname: McD Young
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Voce
authors.affiliation: Centre for Youth Substance Abuse Research, University of Queensland, Brisbane, Queensland, Australia; Disciplines of Psychiatry and Addiction Medicine, Faculty of Medicine, University of Sydney, New South Wales, Australia.
authors.forename: John B
authors.initials: JB
authors.lastname: Saunders
mesh_terms: D000328:Adult; D019969:Amphetamine-Related Disorders / Q000150:complications / Q000175:diagnosis* / Q000523:psychology*; D001526:Behavioral Symptoms / Q000150:complications / Q000175:diagnosis / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000175:diagnosis* / Q000523:psychology*; D008694:Methamphetamine / Q000009:adverse effects*; D011605:Psychoses, Substance-Induced / Q000150:complications / Q000175:diagnosis / Q000523:psychology; D063189:Symptom Assessment
chemical_list: D008694:Methamphetamine
keywords: Amphetamine; Methamphetamine; Psychotic disorders; Schizophrenia; Substance-related disorders