Patient Cohort Information

Inclusion Criteria

• Age 45 -90 years overall.

• Patients aged >65 but <90 years,  presenting with possible Alzhimer’s Disease in the early stages where a definitive diagnosis remains unclear but both nueropsychometric testing and neuroimaging findings  are suggestive of the illness.

• Patients aged >65 but <90 years diagnosed with Mild Cognitive Impariment( MCI). MCI is diagnosed according to established clinical consensus criteria and neuropsychological assessments (>1.5 SD memory or non-memory domain). Subjects are classified as having amnesic or non-amnesic MCI and single or multi-domain impairment, depending on the cognitive profile. Disease subtype is diagnosed according to standardized criteria (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, DSM IV-R) and includes the results of neuroimaging and neuropsychological testing. Cognitive score ≤ 1.5 SD on standardised cognitive tests compared to age-matched normals for MCI.

• Patients aged >45 but <65 years  diagnosed with early onset neurodegenration/dementia (DSM IV-R criteria age <65)

Exclusion Criteria

• Psychiatric illness: major depression, bipolar affective disorder and schizophrenia or schizoaffective disorder
• Normal pressure hydrocephalus
• Seizure disorder
• Brain tumour
• Alcohol or drug abuse/dependence (within the past 2 years)
• History of significant head trauma followed by persistent neurologic defaults
• Known structural brain abnormalities
• History of stroke disease
• Screening/baseline MRI scan with evidence of infection, infarction, or other focal lesions
• Subjects with multiple lacunes or lacunes in a critical memory structure shown on neuroimaging.
• Any significant systemic illness or unstable medical condition, which could lead to difficulty complying with the protocol.
• Current use of warfarin (exclusionary for lumbar puncture).

Control Study Subjects

Cognitively intact aged -matched controls will be recruited from other Irish sites where they are undergoing lumber puncture for other indications/ clinical reasons and there ethical approval is in place to allow CSF samples to been taken from control subjects. These patients will provide consent for use of part of their CSF sample for this research study and will undergo brief cognitive testing to exclude cognitive impairment- MoCA score must be greater than 23.