International research has significantly boosted scientists’ understanding of brain structure differences in those with bipolar disorder as well as how lithium — introduced in the late 1940s and still considered one of the most effective treatments — affects brain anatomy.
Eleven international research groups collaborated in an immense research effort — published in Biological Psychiatry — to gather brain images of adults with bipolar disorder. This mega-analysis allowed them to compare the brain structure differences between individuals with bipolar disorder and healthy subjects.
These studies identified differences — mostly reductions –in the size of brain regions associated with mood regulation in bipolar patients and also provided evidence that certain treatments for bipolar disorder would increase the mass of these brain regions.
The brain images revealed that individuals suffering from bipolar disorder had increased right lateral ventricular, left temporal lobe, and right putamen volumes. Bipolar patients who were not taking lithium had a reduction in cerebral and hippocampal volumes compared with the healthy subjects.
However, individuals with bipolar disorder taking lithium showed significantly increased hippocampal and amygdala volume compared with patients not treated with lithium and healthy comparison subjects. A reduction in cerebral volume was also strongly associated with illness duration in bipolar individuals.
“This important mega-analysis provides strong support for regional brain structural alterations associated with bipolar disorder, but also sends a signal of hope that treatments for this disorder may reduce some of these deficits,” commented Dr. John Krystal, editor of Biological Psychiatry.