How
schizophrenia and anti-psychotics shrink the brain
UI study documents the illness's effect on brain
tissue
By:
Jude Gustafson | 2013.09.10 | 08:00 AM
It’s
hard to fully understand a mental disease like schizophrenia without peering
into the human brain. Now, a study by University of Iowa psychiatry professor
Nancy Andreasen uses brain scans to document how schizophrenia impacts brain
tissue as well as the effects of anti-psychotic drugs on those who have
relapses.
Nancy Andreasen
Andreasen’s
study, published in the American Journal of
Psychiatry, documented brain changes seen in MRI scans from more than 200
patients beginning with their first episode and continuing with scans at
regular intervals for up to 15 years. The study is considered the largest
longitudinal, brain-scan data set ever compiled, Andreasen says.
Schizophrenia
affects roughly 3.5 million people, or about one percent of the U.S.
population, according to the National Institutes of Health. Globally, some 24
million are affected, according to the World Health Organization.
The
scans showed that people at their first episode had less brain tissue than
healthy individuals. The findings suggest that those who have schizophrenia are
being affected by something before they show outward signs of the disease.
Nancy Andreasen and her lab are using brain scans from magnetic resonance imaging to better understand how anti-psychotic drugs affect the brains of schizophrenia patients.
“There
are several studies, mine included, that show people with schizophrenia have
smaller-than-average cranial size,” explains Andreasen,
whose appointment is in the Carver College of Medicine. “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.”
Andreasen’s
team learned from the brain scans that those affected with schizophrenia
suffered the most brain tissue loss in the two years after the first episode,
but then the damage curiously plateaued—to the group's surprise. The finding
may help doctors identify the most effective time periods to prevent tissue
loss and other negative effects of the illness, Andreasen says.
The
researchers also analyzed the effect of medication on the brain tissue. Although
results were not the same for every patient, the group found that in general,
the higher the anti-psychotic medication doses, the greater the loss of brain
tissue.
“This
was a very upsetting finding,” Andreasen says. “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?'”
The
group also examined how relapses could affect brain tissue, including whether
long periods of psychosis could be toxic to the brain. The results suggest that
longer relapses were associated with brain tissue loss.
The
insight could change how physicians use anti-psychotic drugs to treat
schizophrenia, with the view that those with the disorder can lead productive
lives with the right balance of care.
“We
used to have hundreds of thousands of people chronically hospitalized. Now,
most are living in the community, and this is thanks to the medications we
have,” Andreasen notes. “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, 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.”
The
study was published in June and was funded by Janssen Scientific Affairs, the
National Institutes of Health (grant number:R01 MH097751)and the Brain &
Behavior Research Foundation. Contributing authors, all from the UI, include
associate psychiatry professor Beng-Choon Ho, visiting faculty Dawei Liu,
resident AnviVora and senior research assistant Steven Ziebell.
This
story appeared originally on the Department of Psychiatry website and has been re-purposed for Iowa Now.
Contacts
Nancy Andreasen, Psychiatry, 319-356-1553
Richard Lewis, University Communication and
Marketing, 319-384-0012
No comments:
Post a Comment
PLEASE ADD COMMENTS SO I CAN IMPROVE THE INFORMATION I AM SHARING ON THIS VERY IMPORTANT TOPIC.