Using Optical Coherence Tomography to Screen for Cognitive Impairment and Dementia

Area of Science:

• Neuroscience
• Ophthalmology
• Gerontology

Background:

• Screening for Alzheimer's disease and related disorders (ADRD) and mild cognitive impairment (MCI) is crucial for early intervention and clinical trial enrollment.
• Neurodegenerative changes are key indicators for effective screening measures.
• Optical coherence tomography (OCT) is being explored as a potential biomarker for neurodegeneration within the amyloid-tau-neurodegeneration (ATN) framework.

Purpose of the Study:

• To evaluate the utility of OCT measurements as a screening tool for detecting individuals with MCI and ADRD.
• To determine if OCT can serve as a practical, non-invasive biomarker for neurodegeneration.

Main Methods:

• A retrospective cross-sectional study involving 136 participants with comprehensive clinical, cognitive, and functional evaluations.
• OCT measurements were taken, with a subset also undergoing volumetric MRI.
• Statistical analyses included Pearson correlation coefficients and receiver operator characteristic curves to assess OCT's discriminatory ability.

Main Results:

• Granular cell layer-inner plexiform layer (GCL+IPL) thickness, an OCT measurement, showed the strongest correlation with memory, global cognitive performance, and hippocampal atrophy after controlling for age.
• A GCL+IPL thickness cut-off score of 75μm effectively discriminated cognitive status.
• A multimodal approach combining GCL+IPL thickness with patient-reported outcomes and performance measures achieved 87% accuracy in classifying MCI and ADRD participants.

Conclusions:

• Multimodal strategies can enhance the identification of individuals with MCI and ADRD.
• OCT presents a viable, non-invasive biomarker for ADRD screening, facilitating early identification for further evaluation and research.