Rapid Picture Naming, Low-Contrast Letter Acuity May Help Identify Alzheimer Disease

Closeup of a man’s hand on his wife shoulder as he comforts her during a serious conversation with a female neurologist. The doctor is showing the patient an MRI scan of the patient’s brain.
Researchers evaluated cognitively normal individuals from individuals with mild cognitive impairment caused by Alzheimer disease with several tests.

The following article is a part of conference coverage from the 2021 meeting of the North American Neuro-Ophthalmology Society, being held virtually from February 20 to 23, 2021. The team at Ophthalmology Advisor will be reporting on the latest news and research conducted by these leading experts in neuro-ophthalmology. Check back for more from the NANOS 2021 Meeting.

 

Evaluations using rapid picture naming and level of low-contrast letter acuity distinguished patients with mild cognitive impairment (MCI) due to Alzheimer disease from patients who were aging normally in a study that researchers presented at the North American Neuro-Ophthalmology Society 2021 Annual Meeting.

Rapid automatized naming (RAN) tests have had some success in detecting mild cognitive impairment, the report explains. The researchers sought to evaluate the utility of new RAN tests and measures of visual pathway structure and function for identifying Alzheimer disease. While the disease is often diagnosed in the dementia stage after clinical symptoms present, biomarkers can precede them during the prodromal phase of MCI. They also assessed whether the tests correlated with vision-specific quality of life scores, which can also be used in disease detection.

In the cross-sectional, case-control study, 14 participants with MCI due to AD and 16 controls with normal cognition underwent several tests. Each group had an average age of approximately 75 years with an average of 17 years of education and roughly 20/20 corrected vision.

The testing included high- and low-contrast letter acuity (LCLA), the Mobile Universal Lexicon Evaluation System (MULES) and Staggered Uneven Number (SUN) rapid automatized naming tests, optical coherence tomography (OCT) optic nerve head and macula scans, and the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) and Neuro-ophthalmic Supplement vision-specific tests. A cognitive neurologist also assessed the patients for hippocampal atrophy on magnetic resonance imaging (MRI).

Participants with MCI had lower LCLA (P =.009) and worse MULES time (P =.006) with more errors in naming pictures tests (P =.009) compared with the controls. When the researchers controlled for ocular pathology, these measures were significant predictors of MCI vs control status. More MULES errors (rs=-.5, P =.005) and worse 1.25% LCLA scores (rs=.39, P =.03) were associated with worse NEI-VFQ-25 scores.

“In this pilot study, rapid picture naming and low-contrast letter acuity are sensitive measures that distinguish mild cognitive impairment due to Alzheimer disease from those with normal aging. …. These easily-administered tests are promising for identifying patients at risk for AD dementia and serving as measures in disease-modifying therapy clinical trials,” according to the researchers.

Visit Ophthalmology Advisor’s conference section for complete coverage of the NANOS 2021 Meeting and more.


Reference

Wu SZ, Nolan-Kenney R, Moehringer N, et al. Exploring rapid automatized naming and standard visual tests for detection of early Alzheimer’s disease. Presented at: North American Neuro-Ophthalmology Society Annual Meeting; February 20-23, 2021; Poster 137.