title: Decreased striatal dopamine transporter binding assessed with [123I] FP-CIT in first-episode schizophrenic patients with and without short-term antipsychotic-induced parkinsonism.
abstract: BACKGROUND
  Drug-induced parkinsonism (DIP) is one of the main causes of treatment drop-out in schizophrenic patients causing a high incidence of relapse that leads patients to a bad clinical prognosis. The dopaminergic nigrostriatal pathway is involved in the movement control, so the study of the dopamine transporter (DAT) could be of great value to determine its implication in the appearance of DIP.
  
  
  OBJECTIVE
  The goal of the study is to determine the striatal DAT binding assessed with [(123)I] FP-CIT SPECT in first-episode neuroleptic-naive schizophrenic in-patients with DIP after short-term antipsychotic treatment.
  
  
  METHODS
  The [(123)I] FP-CIT binding ratios of ten schizophrenic in-patients who developed DIP during the first 4-week period of risperidone treatment (6+/-2 mg/day) were compared with ten schizophrenic in-patients treated with the same doses of risperidone and who do not developed DIP and with ten age-matched healthy subjects. Quantitative analyses of SPECTs were performed using regions of interest located in caudate, putamen and occipital cortex. Parkinsonism was assessed by the Simpson-Angus Scale and the psychopathological status by the Clinical General Impression and Positive and Negative Syndrome Scales.
  
  
  RESULTS
  Whole striatal [(123)I] FP-CIT binding ratios were significantly lower in patients with and without DIP than in healthy subjects (p<0.001). This was also observed in whole putamen (p<0.001) and caudate nucleus (p<0.001). Females showed higher whole striatal [(123)I] FP-CIT binding ratios than males (p<0.05). No differences in psychopathological scales were observed between patients with and without DIP.
  
  
  CONCLUSIONS
  Our first-episode schizophrenic patients with and without DIP after short-term risperidone treatment have a decreased striatal DAT binding assessed with [(123)I] FP-CIT. This alteration could be related to the schizophrenic disease or may be secondary to the antipsychotic treatment.
authors.affiliation: Nuclear Medicine Department, Hospital Clinic of Barcelona, University of Barcelona, Spain. jose.javier.mateos@amersham.com
authors.forename: Jose J
authors.initials: JJ
authors.lastname: Mateos
authors.forename: Francisco
authors.initials: F
authors.lastname: Lomeña
authors.forename: Eduardo
authors.initials: E
authors.lastname: Parellada
authors.forename: Mireia
authors.initials: M
authors.lastname: Font
authors.forename: Emili
authors.initials: E
authors.lastname: Fernandez
authors.forename: Javier
authors.initials: J
authors.lastname: Pavia
authors.forename: Alberto
authors.initials: A
authors.lastname: Prats
authors.forename: Francisca
authors.initials: F
authors.lastname: Pons
authors.forename: Miquel
authors.initials: M
authors.lastname: Bernardo
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use; D001667:Binding, Competitive; D006801:Humans; D007457:Iodine Radioisotopes; D017072:Neostriatum / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism*; D010302:Parkinson Disease, Secondary / Q000139:chemically induced*; D012559:Schizophrenia / Q000188:drug therapy / Q000378:metabolism*; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014326:Tropanes / Q000378:metabolism* / Q000493:pharmacokinetics
chemical_list: D014150:Antipsychotic Agents; D007457:Iodine Radioisotopes; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane