Cerebrospinal fluid apolipoprotein E level is increased in late-onset Alzheimer's disease

Worldwide evidence has recently shown that the allele e4 of apolipoprotein E (apoE) is a genetic risk factor for Alzheimer's disease (AD) underlining the possible role of apoE in the physiopathology of AD. To evaluate the rol e of apoE concentration in the pathogenesis of AD, we measured its level in the cerebrospinal fluid (CSF). Concentrations were significantly higher in 38 patients with late-onset AD compared to 31 control patients and 47 pati ents suffering from other neurological and related diseases. Higher levels of CSF apoE were also present in a subset of patients with meningoencephali tis, motor neuron disease and low back pain. The increase of CSF apoE in AD is in agreement with results from studies that find an increase of mRNA ap oE in the brains of AD patients. These results emphasise the difficulties a nd importance of the selection of suitable controls. The CSF apoE level see ms to be a reflection of neuronal damage and/or an inflammatory reaction th at may be common to AD and other neurological and related diseases.