Reduction of cerebral blood flow in older depressed patients.
BACKGROUND
We investigated regional cerebral blood flow in older, drug-free depressed patients and examined factors that might be related to rCBF.


METHODS
We studied 39 physically healthy depressed patients over the age of 50 years and 20 psychiatrically healthy control subjects. Regional cerebral blood flow was measured with single photon emission computed tomography, using both xenon 133 (to quantify regional cerebral blood flow) and 99mTc-hexamethylpropylene amine oxime (to make regional comparisons). From magnetic resonance imaging, we derived a semiquantitative measure of areas of white matter hyperintensity and a ventricle-to-brain ratio.


RESULTS
Patients exhibited a global reduction in regional cerebral blood flow compared with controls, with the orbital frontal and inferior temporal areas affected bilaterally. Regional cerebral blood flow was also reduced in higher brain slices in the right but not the left hemisphere. Significant predictors of lowered regional cerebral blood flow were being depressed, being male, and having a greater ventricle-to-brain ratio. There appeared to be a subgroup of patients who demonstrated large areas of white matter hyperintensity and low regional cerebral blood flow.


CONCLUSIONS
Cerebral blood flow was lower in older, medication-free depressed patients than in age-matched control subjects, involved the orbital frontal and anterior temporal regions, and was more reduced in the right hemisphere.
Lesser
I M
IM
Department of Psychiatry, Harbor-UCLA Medical Center, Torrance.
Mena
I
I
Boone
K B
KB
Miller
B L
BL
Mehringer
C M
CM
Wohl
M
M
D000367:Age Factors; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D003866:Depressive Disorder / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010091:Oximes; D011336:Probability; D012737:Sex Factors; D019690:Technetium Tc 99m Exametazime; D013702:Temporal Lobe / Q000098:blood supply; D015899:Tomography, Emission-Computed, Single-Photon; D014980:Xenon Radioisotopes
D015609:Organotechnetium Compounds; D010091:Oximes; D014980:Xenon Radioisotopes; D019690:Technetium Tc 99m Exametazime