title: Preliminary evidence of striatal D2 receptor density as a possible biological marker of prognosis in naive schizophrenic patients.
abstract: With the aim of investigating a possible biological marker of prognosis in schizophrenia, the relationship between striatal dopaminergic D2 receptor (D2R) density and clinical prognostic factors was studied in an initial sample of nine neuroleptic-naive schizophrenic patients. Previous psychosocial adaptation was evaluated by means of the Premorbid Adjustment Scale (PAS). Based on the four DSM-IV criteria in schizophreniform disorder for good prognosis, patients were divided in two groups: good prognosis if > or =2 criteria were met (n=5) and poor prognosis if <2 criteria were met (n=4). D2R density was assessed by means of 123I-IBZM single photon emission computed tomography (SPECT) and striatum/occipital uptake ratios (S/O). S/O ratios previously obtained from a control group of nine age- and sex-matched healthy volunteers were used for comparison.
  
  
  RESULTS
  Patients with poor prognosis showed a higher S/O ratio (mean=1.94, range=1.93-1.98) than patients with good prognosis (mean=1.64, range=1.52-1.79) and the control group (mean=1.69, range=1.51-1.85) [analysis of variance (ANOVA) F=10.628, df=2, P=.001, post hoc Scheffé P<.005]. PAS scores were significantly different between patients with good and poor prognosis (40+/-9.39 vs. 84.25+/-26, Mann-Whitney U-test P=.014). A direct correlation of S/O ratios with PAS scores was found (Spearman r=.72, P=.028).
  
  
  CONCLUSIONS
  Striatal D2R density in naive schizophrenic patients may be related to DSM-IV prognostic factors and premorbid adjustment criteria (PAS). If these preliminary results are confirmed, striatal D2R density might predict premorbid and clinical features associated with poor prognosis in neuroleptic-naive patients.
authors.affiliation: Department of Psychiatry and Nuclear Medicine, Sta. Creu and St. Pau Hospital, Autonomous University of Barcelona (UAB) [corrected] Barcelona, Spain. vperez@hsp.santpau.es
authors.forename: Víctor
authors.initials: V
authors.lastname: Pérez
authors.forename: Ana M
authors.initials: AM
authors.lastname: Catafau
authors.forename: Iluminada
authors.initials: I
authors.lastname: Corripio
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Martín
authors.forename: Enric
authors.initials: E
authors.lastname: Alvarez
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D015415:Biomarkers; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D011379:Prognosis; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D018967:Risperidone / Q000378:metabolism; D012559:Schizophrenia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism*; D018709:Statistics, Nonparametric; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D015415:Biomarkers; D017448:Receptors, Dopamine D2; D018967:Risperidone