Schizophrenia Drugs May Spur Subtle Brain Tissue Loss
Doctors should prescribe lowest effective dose of antipsychotic med, experts say
MONDAY, Feb. 7, 2011 (HealthDay News) -- The use of antipsychotic drugs to treat schizophrenia is associated with the loss of a small but measurable amount of brain tissue, a new study finds.
It included 211 schizophrenia patients who each underwent an average of three MRI brain scans over 7.2 years, for a total of 674 scans in the study group. The researchers then examined how four factors affected changes in brain volume over time: illness duration, illness severity, substance abuse and treatment with antipsychotic drugs.
Longer duration of illness and antipsychotic treatment were both associated with loss of brain tissue. Higher doses of antipsychotics were associated with overall brain tissue loss, reduced gray matter and progressive declines in white matter.
Illness severity and substance abuse had little or no association with brain tissue changes, according to the study, published in the February issue of the Archives of General Psychiatry.
Among young adults, schizophrenia is a leading cause of chronic disability, according to background information in the study. Loss of brain volume in these patients was previously thought to be caused by the illness.
While antipsychotic drugs may lead to brain tissue loss, the benefits of long-term treatment may outweigh the risks, wrote the researchers at the University of Iowa Carver College of Medicine in Iowa City.
"However, our findings point toward the importance of prescribing the lowest doses necessary to control symptoms," they added in a news release from the journal's publisher.
The findings also raise concerns about prescribing antipsychotic drugs for patients with mental health conditions other than schizophrenia, such as bipolar disorder or depression.
The findings shouldn't be seem as a reason to halt the use of antipsychotic drugs to treat schizophrenia, Dr. David A. Lewis, of the University of Pittsburgh, wrote in an accompanying editorial.
"But they do highlight the need to closely monitor the benefits and adverse effects of these medications in individual patients, to prescribe the minimal amount needed to achieve the therapeutic goal, to consider the addition of non-pharmacological approaches that may improve outcomes and to continue the pursuit of new antipsychotic medications with different mechanisms of action and more favorable benefit to harm ratios," he wrote.
The U.S. National Institute of Mental Health has more about schizophrenia.