Pupillary cholinergic hypersensitivity predicts cognitive decline in community dwelling elders
1Laboratory of Higher Cortical Functions, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA. leonard_scinto@hms.harvard.edu
Neurobiology of Aging
|November 23, 2006
Summary
An exaggerated pupil dilation response may indicate a higher risk for developing pre-clinical Alzheimer's disease (AD). This pupil assay is a significant independent risk factor, increasing the risk four-fold.
Area of Science:
- Ophthalmology
- Neurology
- Gerontology
Background:
- Previous studies indicated pupil dilation response can differentiate Alzheimer's disease (AD) patients from controls.
- An exaggerated pupil response to tropicamide suggests potential neurological changes.
Purpose of the Study:
- To investigate the predictive value of an exaggerated pupil response for cognitive decline in elders.
- To assess the pupil assay's ability to identify pre-clinical Alzheimer's disease over time.
Main Methods:
- Prospective longitudinal study of 55 community-dwelling elders over 2-4 years.
- Utilized a pupil assay and comprehensive neuropsychological testing.
- Employed discrete time survival modeling to analyze cognitive decline patterns.
Main Results:
- A hypersensitive pupil response (>/=13% dilation) increased the risk of cognitive impairment (memory, attention, language) by 3-fold.
- Controlling for ApoE allele type elevated the risk to 4-fold.
- Exaggerated pupil response significantly predicted cognitive decline (p=.02).
Conclusions:
- An exaggerated pupil response is a significant, independent risk factor for pre-clinical Alzheimer's disease.
- The pupil assay shows potential for early detection of AD-related cognitive decline.
- Longitudinal data confirms the pupil assay's utility in identifying individuals at increased risk for AD.
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