Neuroimaging of patients with psychosis and NMDA receptor antibodies

  • Research type

    Research Study

  • Full title

    Neurobiological basis of psychotic symptoms in patients with anti-NMDA receptor antibodies: pilot study

  • IRAS ID

    153167

  • Contact name

    Thomas Pollak

  • Contact email

    thomas.pollak@kcl.ac.uk

  • Duration of Study in the UK

    2 years, 0 months, 1 days

  • Research summary

    This study aims to clarify the biological basis of psychotic symptoms in patients who have psychosis and who test positive for a blood test looking for specific antibodies which target the NMDA receptor (NMDAR) in the brain.

    It is thought that some cases of psychosis may be related to dysfunction in the immune system. Recently there has been much interest in whether antibodies – specialized immune system molecules – can cause psychosis. NMDAR antibodies target a brain receptor that is involved in brain signaling involving the neurotransmitter glutamate. Blocking the NMDAR with drugs can cause psychosis and it is thought this may come about by increasing levels of brain glutamate. We aim to see whether patients with a diagnosis of psychosis and NMDAR antibodies also have abnormal levels of brain glutamate. We will use a neuroimaging technique called magnetic resonance spectroscopy (MRS) to look at levels of glutamate in the brains of people with psychosis who have NMDAR antibodies and compare them with people with psychosis who do not have NMDAR antibodies and healthy matched controls. MRS is a safe and non-invasive brain scanning technology which uses a magnetic resonance imaging (MRI) scanner.

    Each participant will be scanned once. We predict:

    1) Patients with psychosis and NMDAR antibodies will have higher levels of glutamate than both patients with psychosis without NMDAR antibodies and healthy controls in a brain area called the anterior cingulate cortex;
    2) Patients with NMDAR antibodies will have higher levels of peripheral blood markers of a disrupted BBB than patients without NMDAR antibodies or controls.

  • REC name

    London - Bloomsbury Research Ethics Committee

  • REC reference

    14/LO/2145

  • Date of REC Opinion

    12 Dec 2014

  • REC opinion

    Favourable Opinion