Frontal white matter biochemical abnormalities in late-life major depression detected with proton magnetic resonance spectroscopy.
OBJECTIVE
Neuroanatomical abnormalities have been identified in patients with late-life mood disorders by using magnetic resonance imaging. This study examined the biochemical correlates of late-life major depression in the frontal gray and white matter by using single-voxel proton spectroscopy.


METHODS
Twenty elderly patients with major depression and 18 comparison subjects similar in age and gender to the patients were scanned on a 1.5-T magnetic resonance scanner with head coil. Voxels were placed in the left dorsolateral white matter and bilaterally in the anterior cingulate gray matter. Absolute levels of N-acetylaspartate, choline, myo-inositol, and creatine were estimated with the LC-Model algorithm. Ratios of metabolite to creatine levels were computed from the absolute values.


RESULTS
myo-Inositol/creatine and choline/creatine ratios were significantly higher in the frontal white matter in the major depression group than in the comparison group. The groups had no significant differences in the metabolite ratios in the gray matter.


CONCLUSIONS
Biochemical changes in the white matter may provide some of the neurobiological substrates to late-life major depression.
Kumar
Anand
A
Department of Psychiatry, University of California, Los Angeles, School of Medicine, USA. akumar@mednet.ucla.edu
Thomas
Albert
A
Lavretsky
Helen
H
Yue
Kenneth
K
Huda
Amir
A
Curran
John
J
Venkatraman
Talaignair
T
Estanol
Laverne
L
Mintz
Jim
J
Mega
Michael
M
Toga
Arthur
A
D000368:Aged; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000503:physiopathology*; D004292:Dominance, Cerebral / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology*; D006179:Gyrus Cinguli / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007294:Inositol / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D012016:Reference Values
D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline