Hippocampal volumes in adults with bipolar disorder
Children of parents with bipolar disorder (BD), especially those with attention deficit hyperactivity disorder (ADHD) and symptoms of depression or mania, are at significantly high risk for developing BD.
As we have previously shown amygdalar reductions in pediatric BD, the current study examined amygdalar volumes in offspring of parents (BD offspring) who have not yet developed a full manic episode.
In the current study, we examined regional brain morphology in youth with MDD and BD as compared to controls.
Regional brain volumes were measured in 32 MDD subjects (15.7 ± 2.1 years), 14 BD subjects (16.0 ± 2.4 years) and 22 healthy controls (16.0 ± 2.8 years) using magnetic resonance imaging (MRI).
Structural abnormalities in frontal, limbic and subcortical regions have been noted in adults with both major depressive disorder (MDD) and bipolar disorder (BD).
Bipolar offspring do not show decreased amygdalar volume, possibly because these abnormalities occur after more prolonged illness rather than as a preexisting risk factor.
Longitudinal studies are needed to determine whether amygdalar volumes change during and after the development of BD.
Regions of interest included the hippocampus, dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC), caudate, putamen and thalamus.
Volumetric differences between groups were significant (F 0.045 respectively).