CSF excitatory amino acids and severity of illness in Alzheimer's disease

Researchers have proposed that increased release of excitatory amino acids (EAAs) is involved in the pathogenesis of dementia of the Alzheimer type (DAT), and CSF EAA concentrations have been measured to obtain evidence in support of this hypothesis. However, previous comparisons of CSF EAA concentrations in patients with DAT and in controls have yielded inconsistent results, perhaps because patient samples have been heterogeneous as to dementia severity. To determine whether there are changes in CSF concentrations of EAAs related to severity of illness in patients with DAT, we measured CSF concentrations of glutamate, aspartate, and taurine in 32 subjects with DAT, in whom we also assessed the severity of illness using clinical and neuropsychological measures, and 11 age-matched controls. The results suggested that increased CSF aspartate and glutamate concentrations, as well as decreased taurine concentrations, may occur in some persons with more advanced symptoms of DAT.