Hippocampal to pituitary volume ratio: a specific measure of reciprocal neuroendocrine alterations in alcohol dependence.
OBJECTIVE
Studies to date provide conflicting views of the relationship between corticosteroids and decreased hippocampal volume in alcoholism. If this were mediated through the hypothalamic-pituitary-adrenal (HPA) axis, enlarged pituitary volumes relative to hippocampal volumes might be expected and be measurable using the hippocampus to pituitary volume (H:P) ratio.


METHODS
Using magnetic resonance imaging (MRI), we performed volumetric analysis of the pituitary and hippocampus on 10 subjects with alcohol dependence (AD) and on 10 normal control subjects.


RESULTS
Compared to normal controls, AD subjects demonstrated a trend towards decreased hippocampal volume (p < .06) and increased pituitary volume (p < .07). More importantly, H:P ratios were significantly smaller in AD subjects (p < .01). This observation persisted even when covaried for age.


CONCLUSIONS
Reduced H:P ratio fits the hypothesis that ethanol stimulates pituitary corticotrophs resulting in elevated corticosteroid levels and possible injury to the hippocampus. If replicated, reduced H:P ratio may serve as a clinical measure of reciprocal neuroendocrine changes in chronic heavy ethanol use.
Beresford
T
T
Department of Psychiatry, University of Colorado Health Sciences Center, Department of Veterans Affairs Medical Center, Denver, USA.
Arciniegas
D
D
Rojas
D
D
Sheeder
J
J
Teale
P
P
Aasal
R
R
Sandberg
E
E
Reite
M
M
D000305:Adrenal Cortex Hormones / Q000097:blood; D000328:Adult; D000437:Alcoholism / Q000378:metabolism / Q000473:pathology*; D000704:Analysis of Variance; D016022:Case-Control Studies; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010902:Pituitary Gland / Q000378:metabolism / Q000473:pathology*
D000305:Adrenal Cortex Hormones