Hippocampal glucose metabolism is associated with cerebrospinal fluid estrogen levels in postmenopausal women with Alzheimer's disease.

Animal studies indicate that estrogens, such as 17beta-estradiol (E(2)), may enhance hippocampal metabolism and function. In postmenopausal Alzheimer's disease (AD) patients, cerebrospinal fluid (CSF) E(2) levels were significantly lower than in non-demented controls. This finding was inversely correlated with CSF beta-amyloid levels. To address the potential impact of this finding, E(2) levels in CSF were correlated with regional cerebral [18F]2-fluoro-2-deoxy-D-glucose (FDG) uptake as measured using positron emission tomography (PET) in six postmenopausal AD patients. CSF E(2) levels were determined using an electro-chemiluminescence-immunoassay on the Roche Elecsys 2010 immunoassay analyzer. Basic image processing was done by MEDx, using SPM routines for spatial normalization and statistics. CSF E(2) levels were significantly correlated with cerebral glucose metabolism in the left hippocampus. This is the first clinical study indicating an association between CSF E(2) concentration and hippocampal glucose metabolism in postmenopausal women with AD.