Amygdala volume marks the acute state in the early course of depression.
BACKGROUND
The amygdala and hippocampus play a key role in the neural circuitry mediating depression. It remains unclear how much structural and functional changes of amygdala and hippocampus reflect the acute state of depression or an underlying neurobiological trait marker of depression.


METHODS
High-resolution anatomical images were acquired in 20 medication-naïve major depressive disorder (MDD) patients with a current first episode, 20 medication-free patients recovered from a first episode of MDD, and 20 healthy control subjects that were matched for age, gender, and level of education. Manual volumetry of amygdala and hippocampus was performed on coronal images. Volumetric measurements of brain volume and intracranial volume were acquired with automatic segmentation procedures.


RESULTS
Both amygdalae were significantly enlarged in currently depressed patients, whereas there was no significant difference between recovered patients and control subjects. The amygdala enlargement correlated positively with the severity of depressive state but with no other clinical or neuropsychological variable. The hippocampal volume did not differ between groups.


CONCLUSIONS
A state related increase of amygdala volume can be detected early in the course of MDD. Neurotoxic effects might account for the fact that state-related amygdala enlargement has not been found in recurrent depression with relative long illness duration.
van Eijndhoven
Philip
P
Department of Psychiatry, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. P.vanEijndhoven@psy.umcn.nl
van Wingen
Guido
G
van Oijen
Koen
K
Rijpkema
Mark
M
Goraj
Bozena
B
Jan Verkes
Robbert
R
Oude Voshaar
Richard
R
Fernández
Guillén
G
Buitelaar
Jan
J
Tendolkar
Indira
I
D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000473:pathology*; D001921:Brain / Q000473:pathology; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D012720:Severity of Illness Index