Study reveals how schizophrenia affects the brain
Scientists have discovered how schizophrenia and the use of anti-psychotic drugs can impact brain tissue by reviewing progressive data from brain scans, according to a study published in the American Journal of Psychiatry.
Researchers from the University of Iowa, led by psychiatry professor Nancy Andreasen, analyzed 202 MRI scans of patients who suffer from the mental disorder.
All patients had their scans reviewed from their first schizophrenic episode and at regular 6-month intervals up to a period of 15 years.
The researchers say that as clinical follow-up data was obtained every 6 months, they were able to compute measures of relapse number and duration, and relate these to structural MRI measures.
They note that as higher treatment intensity has previously been linked to smaller brain tissue volumes, this countereffect was measured in terms of dose-years.
Lack of brain tissue found in schizophrenic patients
Scans from the patients' first episode revealed that they had less brain tissue, compared with healthy individuals without the disorder.
The researchers say this finding suggests that something is affecting the brains of those with schizophrenia before they demonstrate obvious symptoms of the conditions.
Prof. Andreasen explains:
"There are several studies, mine included, that show people with schizophrenia have smaller-than-average cranial size.
Since cranial development is completed within the first few years of life, there may be some aspect of earliest development - perhaps things such as pregnancy complications or exposure to viruses - that on average, affected people with schizophrenia."
The brain scans also showed that those who suffer from schizophrenia demonstrated the highest tissue loss in the first 2 years after their first episode, after which point it slowed down significantly.
Prof. Andreasen says that this finding may help doctors to identify the most effective time periods to prevent tissue loss in schizophrenic patients, as well as other effects caused by the disorder.
Anti-psychotic drugs 'lead to greater loss of brain tissue'
When it came to monitoring the effect of anti-psychotic drugs on schizophrenic patients, the researchers were disappointed with their findings.
The results showed that the higher the dosage of anti-psychotic medication in patients, the more brain tissue was lost.
Prof. Andreasen says:
"This was a very upsetting finding. We spent a couple of years analyzing the data more or less hoping we had made a mistake. But in the end, it was a solid finding that wasn't going to go away, so we decided to go ahead and publish it.
The impact is painful because psychiatrists, patients, and family members don't know how to interpret this finding. 'Should we stop using antipsychotic medication? Should we be using less?'"
Additionally, when analyzing how relapses affected brain tissue, the scans showed that longer relapses were linked to brain tissue loss. The researchers say that this could change the way anti-psychotic drugs are used to treat schizophrenia.
MRI scans have helped Prof. Andreasen and her team see how anti-psychotic drugs affect the brain. Source: University of Iowa
Prof. Andreasen says that many years ago, there were many people chronically hospitalized due to schizophrenia. But now most sufferers of the disorder are in the community, and this is a result of anti-psychotic drugs.
"But antipsychotic treatment has a negative impact on the brain, so we must get the word out that they should be used with great care," she notes.
"Because even though they have fewer side effects than some of the other medications we use, they are certainly not trouble free and can have lifelong consequences for the health and happiness of the people and families we serve."
Medical News Today recently reported on a study that revealed the discovery of 13 genetic clues that could help explain the cause of schizophrenia.
Written by Honor Whiteman
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