The ROSAS Cohort: A Prospective, Longitudinal Study of Biomarkers for Alzheimer's Disease. Strategy, Methods and...

Area of Science:

• Neuroscience
• Biomarkers
• Neurodegenerative Diseases

Background:

• Alzheimer's disease (AD) diagnosis and progression monitoring require reliable biomarkers.
• The Research Of biomarkers in Alzheimer's diseaSe (ROSAS) study was initiated to address this need.
• Understanding the natural course of AD and Mild Cognitive Impairment (MCI) is crucial for early intervention.

Purpose of the Study:

• To identify biofluid and imaging biomarkers for early AD diagnosis.
• To characterize the cognitive and behavioral progression of Alzheimer's disease.
• To outline the ROSAS study's strategy, methodology, and present initial longitudinal findings.

Main Methods:

• A 4-year longitudinal, prospective, monocentric observational study at a French Alzheimer's disease Research centre.
• Inclusion of 387 participants across three groups: dementia of Alzheimer's type (n=184), Mild Cognitive Impairment (n=96), and controls (n=107).
• Data collection included sociodemographics, medical history, medications, neuropsychological assessments, cognitive status, annual blood/urine samples, and MRI at baseline, 1 year, and study end.

Main Results:

• Baseline differences observed in age, education, and ApoEε4 carrier status among groups; cardiovascular/endocrine pathologies were similar.
• During 3-4 years of follow-up, 43.8% of MCI patients progressed to dementia.
• Conversion rates from MCI to AD were 12.7/100 (year 1), 33.9/100 (year 2), and 46.7/100 (year 3).

Conclusions:

• The ROSAS study provides baseline data for a unique French cohort evaluating the natural course of Alzheimer's disease.
• Future analysis of collected biofluid samples (blood and urine) is expected to identify predictive biomarkers for early AD stages.
• Identifying biomarkers for progression from MCI to AD is a key future objective.