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S086-2

Neurobiological Disease Marker in Drug Naïve Schizophrenia Patients

Kao-Chin Chen, Yen Kuang Yang

National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Taiwan

Background/Objective: A major factor driving research into the pathophysiology of schizophrenia
has been responsiveness to antipsychotic (dopamine antagonist) medication. Despite this it remains
unclear whether there is a detectable disorder of dopamine function in patients who develop
schizophrenia and if so, how it relates to other physiological markers of the condition. One reason
why research in this area is such a challenge is the confounding effects of antipsychotic treatment.

Method: A case control study on drug-naive patients with schizophrenia who presented to the
university hospital clinic was carried out. A number of clinical and neurobiological measures,
thought to be possible disease biomarkers were obtained. Patients were assessed before they received
treatment using the following methods: (I) single positron emission computed tomography (SPECT)
- [99mTc] TRODAT-1 for dopamine transporter (DAT) availability; and (II) Electroencephalograms
to test event-related potentials (ERPs). Such measures were also obtained on healthy controls and
appropriate comparisons made.

Result: The mean specific striatal binding ratio showed a trend for a reduction among the patients
compared with controls. The mean P300 ERP showed no overall significant difference between
patients and controls. No effects of DAT availability on P300 latency or amplitude were detected.

Conclusion: Striatal dopamine transporter levels and the P300 ERP are not altered in the early stages
of schizophrenia before medication is introduced, and the DAT availability does not influence the
P300 ERP amplitude or latency.