Increased orbitofrontal cortex levels of choline in depressed adolescents as detected by in vivo proton magnetic resonance spectroscopy

Background: The frontal lobe has beet? implicated in the pathology of depre ssion in adults, Through the use of magnetic resonance spectroscopy, altere d brain choline levels have also been linked to the pathophysiology of affe ctive disorders. Methods: To identify possible alterations in orbitofrontal cortex levels of cytosolic choline in adolescents with and without depression, 22 depressed and 43 control adolescents were recruited, Of those recruited, usable prot on magnetic resonance spectra were acquired from a voxel in the left anteri or medial frontal lobe of 17 depressed (mean age 15.8 +/- 1.6) and 28 healt hy adolescents (mean age 14.5 +/- 1.7), Results: Orbitofrontal cytosolic choline/creatine (Cho/ Cr) ratios (p = .03 2) and cytosolic choline/N-acetyl aspartate (Cho/NAA) ratios (p = .043) wer e significantly higher in the depressed subjects than in the control subjec ts. There were no significant differences between depressed and control sub jects in gray or white matter content within the voxel, Conclusions: These findings suggest that brain cytosolic choline may be inc reased in depressed adolescents in comparison with control subjects and ind ependent of a corresponding structural change, These results are consistent with similar, previously reported findings in adults and suggest that depr ession in adolescents is associated with alterations in orbitofrontal metab olism (C) 2000 Society of Biological Psychiatry.