Alzheimer's disease: a continuum with visual involvements

Lorena Elvira-Hurtado; Inés López-Cuenca; Rosa de Hoz; Mario Salas; Lidia Sánchez-Puebla; Federico Ramírez-Toraño; José A Matamoros; José A Fernández-Albarral; Pilar Rojas; Soraya Alfonsín; María Luisa Delgado-Losada; Ana I Ramírez; Juan J Salazar; Fernando Maestu; Pedro Gil; José M Ramírez; Elena Salobrar-García

doi:10.3389/fpsyg.2023.1124830

Alzheimer's disease: a continuum with visual involvements

Front Psychol. 2023 Jul 6:14:1124830. doi: 10.3389/fpsyg.2023.1124830. eCollection 2023.

Authors

Lorena Elvira-Hurtado¹, Inés López-Cuenca^{1

2}, Rosa de Hoz^{1

2

3}, Mario Salas⁴, Lidia Sánchez-Puebla¹, Federico Ramírez-Toraño^{5

6}, José A Matamoros¹, José A Fernández-Albarral^{1

2}, Pilar Rojas^{1

7}, Soraya Alfonsín^{5

6}, María Luisa Delgado-Losada^{2

6}, Ana I Ramírez^{1

2

3}, Juan J Salazar^{1

2

3}, Fernando Maestu^{2

5

6}, Pedro Gil^{4

8}, José M Ramírez^{1

2

9}, Elena Salobrar-García^{1

2

3}

Affiliations

¹ Ramon Castroviejo Institute for Ophthalmic Research, Complutense University of Madrid, Madrid, Spain.
² Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain.
³ Faculty of Optics and Optometry, Department of Immunology, Ophthalmology and ENT, University of Madrid, Madrid, Spain.
⁴ Memory Unit, Geriatrics Service, Hospital Clínico San Carlos, Madrid, Spain.
⁵ Center for Cognitive and Computational Neuroscience, Laboratory of Cognitive and Computational Neuroscience, Complutense University of Madrid, Pozuelo de Alarcón, Spain.
⁶ Department of Experimental Psychology, Cognitive Psychology and Speech and Language Therapy, Complutense University of Madrid, Pozuelo de Alarcón, Spain.
⁷ Madrid Eye Institute, Gregorio Marañón General University Hospital, Madrid, Spain.
⁸ Department of Medicine, School of Medicine, Complutense University of Madrid, Madrid, Spain.
⁹ Faculty of Medicine, Department of Immunology, Ophthalmology and ENT, University of Madrid, Madrid, Spain.

Abstract

Introduction: Alzheimer's disease (AD) is the most common form of dementia affecting the central nervous system, and alteration of several visual structures has been reported. Structural retinal changes are usually accompanied by changes in visual function in this disease. The aim of this study was to analyse the differences in visual function at different stages of the pathology (family history group (FH+), mild cognitive impairment (MCI), mild AD and moderate AD) in comparison with a control group of subjects with no cognitive decline and no family history of AD.

Methods: We included 53 controls, 13 subjects with FH+, 23 patients with MCI, 25 patients with mild AD and, 21 patients with moderate AD. All were ophthalmologically healthy. Visual acuity (VA), contrast sensitivity (CS), colour perception, visual integration, and fundus examination were performed.

Results: The analysis showed a statistically significant decrease in VA, CS and visual integration score between the MCI, mild AD and moderate AD groups compared to the control group. In the CS higher frequencies and in the colour perception test (total errors number), statistically significant differences were also observed in the MCI, mild AD and moderate AD groups with respect to the FH+ group and also between the control and AD groups. The FH+ group showed no statistically significant difference in visual functions compared to the control group. All the test correlated with the Mini Mental State Examination score and showed good predictive value when memory decline was present, with better values when AD was at a more advanced stage.

Conclusion: Alterations in visual function appear in subjects with MCI and evolve when AD is established, being stable in the initial stages of the disease (mild AD and moderate AD). Therefore, visual psychophysical tests are a useful, simple and complementary tool to neuropsychological tests to facilitate diagnosis in the preclinical and early stages of AD.

Keywords: Alzheimer’s disease; PDT; contrast sensitivity; family history; mild cognitive impairment; visual acuity; visual function.

Copyright © 2023 Elvira-Hurtado, López-Cuenca, de Hoz, Salas, Sánchez-Puebla, Ramírez-Toraño, Matamoros, Fernández-Albarral, Rojas, Alfonsín, Delgado-Losada, Ramírez, Salazar, Maestu, Gil, Ramírez and Salobrar-García.