title: Plasma homovanillic acid in the prodromal phase of schizophrenia.
abstract: BACKGROUND
  Plasma levels of homovanillic acid (pHVA) have been used as a peripheral measure of central dopaminergic activity. Despite a large body of studies investigating pHVA in schizophrenia, little is known about pHVA in patients in the prodromal phase of the illness.
  
  
  METHODS
  Plasma HVA levels of 12 male outpatients meeting DSM-III-R criteria for the prodromal phase of schizophrenia at the time of blood sampling (who later developed psychotic symptoms) were compared with those of 12 normal male healthy volunteers. Task amounts in the Kraepelin arithmetic test at the time of blood sampling were compared between the prodromal patients and normal controls and were correlated with pHVA levels.
  
  
  RESULTS
  The prodromal patients had significantly higher pHVA levels compared with normal control subjects. The mean amount of the arithmetic task for the prodromal patients was significantly less than that for controls. In the patient group, a significant negative correlation was observed between pHVA levels and the task amounts.
  
  
  CONCLUSIONS
  Data from the present study indicate the presence of dopaminergic dysfunction in the prodromal stage of schizophrenia that is associated with neuropsychological impairment. Increased pHVA levels in the prodromal patients may have implications for early detection of schizophrenia.
authors.affiliation: Department of Neuropsychiatry, Toyama Medical and Pharmaceutical University, School of Medicine, Toyama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sumiyoshi
authors.forename: M
authors.initials: M
authors.lastname: Kurachi
authors.forename: K
authors.initials: K
authors.lastname: Kurokawa
authors.forename: T
authors.initials: T
authors.lastname: Yotsutsuji
authors.forename: T
authors.initials: T
authors.lastname: Uehara
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: O
authors.initials: O
authors.lastname: Saitoh
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D004298:Dopamine / Q000378:metabolism; D006719:Homovanillic Acid / Q000097:blood* / Q000378:metabolism*; D006801:Humans; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D004298:Dopamine; D006719:Homovanillic Acid