The purpose of this study is to validate a diagnostic test that combines different blood markers to identify and correctly classify patients with Alzheimer's disease (AD) compared to individuals with behavioural variant frontotemporal dementia (bvFTD, patient control) versus cognitively healthy individuals (healthy control).

The purpose of this study is to validate a new multi-parameter diagnostic test, on a well-characterised population based on new AD diagnostic criteria, that combines different types of markers, selected based on prior exploratory studies carried out by Raman Health Technologies.

Inclusion Criteria:

1. Healthy controls:

   • Aged between 50-80 years.
   • Men and women.
   • Assessment of the neuropsychological tests confirming the absence of cognitive impairment.
   • Prior to participant inclusion, obtaining the results of the CerebroSpinal Fluid marker analysis (beta-amyloid, Tau protein and p-Tau) carried out in the 24 months before recruitment.

2. Patients diagnosed with Alzheimer's disease (AD).

   • Aged between 50-80 years.
   • Men and women.
   • Patients meet the clinical criteria for Alzheimer's disease:
   • Prior to participant inclusion, results obtained from CerebroSpinal Fluid marker analysis (beta-amyloid, Tau protein and p-Tau) carried out in the 36 months before recruitment.

3. Patients with behavioural variant frontotemporal dementia and primary progressive aphasia: -

   • Aged between 50-80 years.
   • Men and women.
   • Patient meets the clinical criteria of behavioural variant frontotemporal dementia (bvFTD), or syndromes associated with temporal variants that affect language (primary progressive aphasia, agrammatic and semantic subgroups):

(Mild Cognitive Impairment) sub-study: Patients with mild cognitive impairment will be included

• Aged between 50-80 years.
• Men and women.
• Patient meets the clinical criteria for mild cognitive impairment:
• Clinical diagnostic criteria for mild cognitive impairment: NIA-Alzheimer's Association of America criteria, Alzheimer's Dementia, 2011
• Prior to participant inclusion, results obtained from cerebrospinal fluid marker analysis (beta-amyloid, Tau protein and p-Tau) carried out in the 12 months before recruitment.

Exclusion Criteria:

• Severe or acute systemic disease that could impede the participant's follow-up study: Advanced liver or kidney disease and disseminated neoplastic disease
• Addiction to alcohol or other drugs in the last two years based on Diagnostic and Statistical Manual of Mental Disorders IV criteria, except nicotine use, which is permitted
• Down's syndrome
• Moderate or severe head injury
• central nervous system infections (HIV, syphilis, borrelia, herpes simplex, suspected Creutzfeldt-Jakob disease)
• Endocrine alterations (thyroid alterations)
• Nutritional deficiency (vitamin B12, folic acid)
• Clinical history of stroke in the previous three months or neuroimaging evidence of clinically significant cardiovascular disease (e.g. strategic infarct or severe leukoencephalopathy).
• Neurological diseases (dysmyelinating disorders, Parkinson's disease, Huntington's disease, normal pressure hydrocephalus, subdural haematoma, brain tumours)
• Major psychiatric disorder (major depression or psychosis)
• Patients who do not have a clearly defined clinical diagnosis according to the study groups (inclusion/exclusion criteria)
• Disease which, in the investigator's or sponsor's judgement, may have a potentially significant influence and thus generate bias in the study markers.

It is estimated that a sample of 500 patients (250 with AD and 250 with FTD) and 200 controls (700 individuals in total) will be sufficient to corroborate the hypothesis that permits validation of the new diagnostic test. The sample size estimate is based on a hypothesis of non inferiority between the new test and the test used in normal clinical practice, expecting a 10% delta of the 75% validity, sensitivity and specificity indices with an alpha error of 0.05 and a beta error of 0.20.