Schizophrenia riddle thickens as body attacks brain   

George Aitch 

I Jan 4 2017

Ben Janaway

Schizophrenia is a challenging psychiatric disease. Patients experience unpleasant and strange hallucinations and delusions which may alienate them from the world around them, turning the environment into a source of anxiety and suspicion. We do not currently know exactly what produces these phenomena, though a recent discovery may add another piece to the puzzle.

In a study published in The Lancet Psychiatry, researchers took blood samples from individuals with psychosis and investigated for the presence of antibodies; immune system proteins which also play a role in inflammation and disease. The specific antibodies they were looking for attack a type of nerve receptor present in the brain which is implicated in psychotic illness.

The presence of autoantibodies against N-methyl-D-aspartate receptor (NMDAR) are implicated in the generation of autoimmune encephalitis, that is swelling of the brain as the body attacks itself. Patients with these antibodies, when active and causing brain disease, may experience psychotic symptoms. Patients with schizophrenia were twice as likely to have this type of antibody, though only 9% of the population had it overall.

The findings imply that either certain people with a diagnosis of schizophrenia or bipolar disorder (another mental illness with psychotic features) may have the wrong label and can thus be treated by removing those harmful antibodies OR that schizophrenia may be in part the result of a chronic ongoing inflammatory process in the brain, something which has been suspected in previous investigations into the schizophrenic brain.

Further trials are being carried out to determine whether immunotherapy can benefit patients with these antibodies. Although schizophrenia may be a long way from being cured completely, each step is welcome news for the millions who bravely fight every day.

A note on psychosis

Psychosis is a termed used to describe a mental state where a patient may express ‘delusions’ or ‘hallucinations’.  Psychosis may result from a large variety of illnesses, including delirium from infection, psychiatric disease, use of certain medications, dementias and brain tumours.

Delusions may be best understood as ‘unshakeable’ beliefs in ideas that have no external supporting evidence, and persist in the presence of contradicting evidence. A famous example would be Shakespearean character Othello’s strong belief in the infidelity of his wife. Although Othello had little evidence, his conviction as strong enough to drive him to murder. It is worth remembering this is fictional, and not common in day to day life.

Hallucinations can be described as phenomena experienced by the patient (visual, auditory, feel, smell) but with no external source.  The experience is created wholly within the patient’s mind, but perceived as if present in the real world. A good example would be found in the biopic of mathematician John Nash, where his flatmate from university is revealed to be little more than a manifestation of Nash’s developing disease.
Schizophrenic-type delusions are more commonly of the paranoid ilk, with beliefs of being monitored, watched or having some unique purpose. There may also be feelings of puppetry, being ‘forced’ to undertake actions, think in a certain way, have thoughts stolen or broadcast publically. Hallucinations tend to be auditory in nature and insulting, typically a third person commentary discussing or insulting the patient. There are many subtypes of disease with different features.

Any opinions above are the author's alone and may not represent those of the NHS or Mind and Medicine. Any comment is based on the best available evidence at the time of writing.  All data is based on externally validated studies unless expressed otherwise. Novel data is representative of sample surveyed. Online recommendation is no substitute for seeing your own doctor and should not be taken as medical advice.

Lennox BR, Palmer-Cooper EC, Pollak T, Hainsworth J, Marks J, Jacobson L, Lang B, Fox H, Ferry B, Scoriel L, Crowley H, Jones PB, Harrison PJ, Vincent A. 2016. Prevalence and clinical characteristics of serum neuronal cell surface antibodies in first-episode psychosis: a case-control study. The Lancet Psychiatry.
Bloomfield PS, Selvaraj S, Veronese M, Rizzo G, Bertoldo A, Owen DR, Bloomfield MAP, Bonoldi I, Lalk N, Turkheimer F, McGuire P, de Paola V, Howes OD. 2015. Microglial Activity in People at Ultra High Risk of Psychosis and in Schizophrenia: An [11C]PBR28 PET Brain Imaging Study. Am J Psych. Vol 173 1 pp 44-52