Researchers examined the rates of atrophy, or loss of brain volume, in healthy individuals and patients with schizophrenia. In terms of brain tissue, atrophy specifically means the loss of neurons and their connections. While everyone undergoes atrophy past a certain age (and it's not preventable), patients with schizophrenia exhibit atrophy at a significantly faster rate.
The comparison yielded results that confirmed speculations about the medications used to treat schizophrenia.
After researchers from the University of Oulu, Finland, and the University of Cambridge studied the different rates and recorded exactly which brain regions experienced the atrophy, they confirmed an association with antipsychotic drugs.
The rate of atrophy was higher when the dose of antipsychotic medication was higher. While this association confirms scientists' suspicions of the link, it does not necessarily mean the antipsychotic drugs caused the increased rate of loss of brain volume.
Some researchers believed the difference in rate of atrophy was just a matter of older medications versus newer medications. They argued that older antipsychotic drugs may cause such volume decreases but newer drugs protect against them. However, this study suggests that both kinds of medications lead to the increased rate of atrophy.
The research, which was published in the open access journal PLOS ONE, looked at 33 patients with schizophrenia and 71 healthy subjects, compared their brain scans over a period of 9 years, and measured loss of brain volume. The healthy individuals exhibited atrophy at a rate of 0.5 percent every year, while the patients with schizophrenia exhibited a rate of 0.7 percent.
Juha Veijola, a professor from the University of Oulu Department of Psychiatry, points out that "research like this where patients are studied for many years can help to develop guidelines about when clinicians can reduce the dosage of antipsychotic medication in the long term treatment of people with schizophrenia."
However, the study also examined the possible cognitive declines and symptoms of the increased rate of atrophy. The researchers found none.
"It's important to stress that the loss of brain volume doesn't appear to have any effect on people over the nine year follow-up we conducted, and patients should not stop their medication on the basis of this research," said Dr. Graham Murray from the Department of Psychiatry at the University of Cambridge. He does, however, outline the need for further studies to examine any significant brain changes of the drugs later in life.
