Proposal To Develop A Rapid And Cost-Effective Diagnostic Test For Schizophrenia

Overview

Schizophrenia is a severe psychotic illness of unknown cause that affects 1% of the population worldwide. Currently, there is no diagnostic test for schizophrenia. Instead, the diagnosis is typically established through a psychiatric interview of the patient, who is evaluated against a set of established criteria of signs and symptoms. It can take many months to years to establish a diagnosis of schizophrenia and achieve an appropriate treatment regimen to attain resolution of the patient's symptoms. This process is particularly challenging in areas of limited access to specialists a problem not only in third world countries and rural regions, but throughout the United States where there can be long waits to obtain an appointment with a psychiatrist. The present research experiment investigates a potential novel method for diagnosing schizophrenia. The overall objective of the study is to test the hypothesis that patients with schizophrenia will have a heightened tolerance to the sedating effects of anti-psychotic medications, which will be reflected in differences in their electroencephalogram (EEG) when compared to healthy normal controls. The investigators expect that the schizophrenia patients will score on the "more alert" and "less sleepy" ends of these scales, and that the normal control subjects will show the opposite response. A patient that fails to become sedated or experience the sleepiness side effects, typically caused by the anti-psychotic medication, may support the existing diagnosis of schizophrenia. Measures of the subjects' level of sedation that are found to correlate significantly with EEG response and diagnosis will be used to create a diagnostic test. This simple and inexpensive test will consist of a single dosage of anti-psychotic medication, and a rapid assessment tool with scores that have a high degree of predictive validity for the diagnosis of schizophrenia.

The overall objective of the study is to test the hypothesis that patients with schizophrenia will have a heightened tolerance to the sedating effects of antipsychotic medications, which will be reflected in differences in the participants' electroencephalogram response (EEG), when compared to healthy control participants.The following Specific Aims are designed to test this hypothesis and create the diagnostic tool. Specific Aim 1: The investigators will first conduct a pilot dose-response evaluation of the anti-psychotic drugs ziprasidone (Geodon) (20, 40, or 60 mg tablet) and olanzapine (Zyprexa®) (2.5, 5, 7.5, or 10 mg tablet) in non-psychiatric ill control participants to determine the optimal dosage that promotes sedation in healthy participants versus a placebo. The evaluation will comprise a physical examination and questionnaires. The investigators will start with the lowest dose of each drug and if the dosage fails to induce sedation in healthy participants, the investigators will repeat the pilot dose-response evaluation with the next higher dose until the maximum dose is reached for both drugs. Specific Aim 2. To determine whether the pattern of EEG activity in response to a single dose of the anti-psychotic medication determined from the dose-response study from Aim 1 distinguishes schizophrenia participants from normal controls. The investigators will start with 2-4 healthy control participants to determine that the results show a discernible effect on the EEG using the dosage from Aim 1. If the dose of anti-psychotic medication fails to show an effect on the EEG the investigators will increase the dosage until the maximum dosage of the chosen medication is used. Once the dosage is identified the investigators will move onto getting IRB approval to evaluate participants diagnosed with schizophrenia.