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Interhemispheric distribution of Alzheimer disease and vascular pathology in brain aging

Panteleimon Giannakopoulos, Enikö Kövari, François R Herrmann

    Stroke
    |January 2, 2009
    PubMed
    Abstract

    Insights

    Brain aging studies often assume symmetrical pathology. This study found that asymmetrical Alzheimer disease and vascular pathology, particularly in the right hemisphere, significantly impacts cognitive decline and dementia risk.

    Area of Science:

    • Neuropathology
    • Neuroscience
    • Cognitive Aging

    Background:

    • Investigated clinicopathological analysis of 153 mixed pathology cases, excluding macroinfarcts, to understand asymmetrical lesion impact on cognition.
    • Assessed cognitive status using Clinical Dementia Rating (CDR) scale and neuropathology including Braak neurofibrillary tangle (NFT) staging, amyloid-beta (Aβ) deposition staging, microvascular pathology, and lacunes.

    Discussion:

    • Vascular pathology scores were significantly higher in the left hemisphere across all CDR scores, unlike Braak NFT and Aβ staging.
    • A negative relationship existed between Braak NFT staging and vascular scores in moderate to severe dementia.
    • Braak NFT staging was the primary determinant of cognitive decline, followed by vascular scores and Aβ deposition staging.

    Key Insights:

    • Cognitive impact of mixed Alzheimer disease and vascular lesions can be assessed unilaterally with minimal information loss.
    • Interhemispheric differences, especially right hemisphere predominance of vascular and Alzheimer disease pathology, elevate dementia risk.

    Outlook:

    • Future research should focus on targeted interventions for asymmetrical neuropathology.
    • Understanding hemispheric lateralization of brain pathology is crucial for accurate dementia risk assessment.

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