Cognitive and Neuroimaging for Neurodegenerative Disorders: A Cohort Study Design with Initial Findings

Area of Science:

• Neurology
• Neuroscience
• Gerontology

Background:

• Dementia exhibits significant heterogeneity across age groups, with early-onset cognitive decline (EOCD) presenting unique diagnostic and management challenges.
• The Cognitive and Neuroimaging for Neurodegenerative Disorders (CogNID) study addresses the complexity of cognitive impairment diagnosis and biomarker utility.

Purpose of the Study:

• To characterize clinical, cognitive, neuroimaging, and biomarker features in a diverse cohort with cognitive impairment.
• To focus on diagnostic complexity, biomarker utility, and mortality differences between early-onset (EOCD) and late-onset cognitive decline (LOCD).

Main Methods:

• Prospective cohort study of 429 participants from NHS memory clinics, including EOCD (<65 years) and LOCD (≥65 years) groups.
• Data collection included structured cognitive assessments, neuroimaging (MRI/CT), and cerebrospinal fluid (CSF) biomarker evaluation.
• Diagnoses were established by multidisciplinary consensus.

Main Results:

• EOCD comprised 81.4% of the cohort (n=349).
• Alzheimer's disease biomarkers were found in 36.4% of tested EOCD participants; Functional Cognitive Disorder (FCD) was more prevalent in EOCD (22.3% vs. 5.0%).
• Mortality was higher in the LOCD group (11.3% vs. 4.6%).

Conclusions:

• The CogNID study highlights the diagnostic heterogeneity in cognitive impairment, especially in younger adults.
• Integrating neuroimaging and CSF biomarkers enhances diagnostic precision and differentiates EOCD from LOCD phenotypes.
• Findings emphasize the need for harmonized diagnostic protocols, accessible biomarkers, and inclusive recruitment in dementia research.