Sialic acid, homocysteine and CRP: potential markers for dementia.

To investigate whether sialic acid could discriminate between healthy age matched controls and patients with dementias of the Alzheimer's type (AD), and pure vascular dementia (VaD). 27 patients and 51 controls were administered the Mini-Mental State Examination (MMSE) and had blood analyzed for levels of total sialic acid, total homocysteine (tHcy), and C-reactive protein (CRP). Significant differences were found between the mean MMSE scores for patients with dementia compared with controls. Sialic acid levels were significantly higher in patients with AD compared with controls and homocysteine levels were higher in VaD. Sialic acid levels discriminated between patients with dementia of the Alzheimer's type and healthy controls only. The MMSE could discriminate between controls and patients with dementia but not between the subtypes and homocysteine was significant for patients with VaD.