The association between retinal vascular fractal dimension and cognitive function in the community-dwelling older adults cohort TIGER

Ting-Yu Wu; Yi-Ting Hsieh; Yu-Hsin Wang; Jeng-Min Chiou; Ta-Fu Chen; Liang-Chuan Lai; Jen-Hau Chen; Yen-Ching Chen

doi:10.1016/j.jfma.2023.04.001

The association between retinal vascular fractal dimension and cognitive function in the community-dwelling older adults cohort TIGER

J Formos Med Assoc. 2023 Oct;122(10):1050-1060. doi: 10.1016/j.jfma.2023.04.001. Epub 2023 Apr 19.

Authors

Ting-Yu Wu¹, Yi-Ting Hsieh², Yu-Hsin Wang³, Jeng-Min Chiou⁴, Ta-Fu Chen⁵, Liang-Chuan Lai⁶, Jen-Hau Chen⁷, Yen-Ching Chen⁸

Affiliations

¹ Department of Ophthalmology, Taipei Medical University-Shuang Ho Hospital, Ministry of Health and Welfare, New Taipei City, Taiwan; Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
² Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
³ Biomedical Technology and Device Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan.
⁴ Institute of Statistical Science, Academia Sinica, Taipei, Taiwan.
⁵ Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.
⁶ Graduate Institute of Physiology, National Taiwan University College of Medicine, Taipei, Taiwan.
⁷ Department of Geriatrics and Gerontology, National Taiwan University Hospital, Taipei, Taiwan; Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan. Electronic address: jhhchen@ntu.edu.tw.
⁸ Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan. Electronic address: karenchen@ntu.edu.tw.

PMID: 37085387
DOI: 10.1016/j.jfma.2023.04.001

Abstract

Background/purpose: The small retinal vessels reflect cerebral microcirculation and its fractal dimension (D_f), representing the complexity of the retinal microcirculation. However, the connection between retinal circulation and cognitive function lacked consistent and longitudinal evidence. This study aimed to explore the association between retinal vascular complexity and cognitive impairment over time in non-demented community-dwelling older adults.

Methods: This four-year prospective cohort study (2015-2019) is part of the ongoing Taiwan Initiative for Geriatric Epidemiological Research (TIGER, 2011 to present). Of the 434 older adults (age >65) recruited, 207 participants were included for analysis. The retinal vascular D_f was assessed by baseline images from fundus photography (2015-2017). Global (Montreal Cognitive Assessment-Taiwanese version, MoCA-T) and domain-specific cognition were assessed at the baseline and 2-year follow-up (2017-2019). The multivariable linear regression models and generalized linear mixed models were used to evaluate the association of D_f with cognitive decline/impairment over time.

Results: Decreased left retinal vascular complexity was associated with poor attention performance (β = -0.40). As follow-up time increased, decreased vascular complexity was associated with poor memory performance (right: β = -0.25; left: β = -0.19), and decreased right vascular complexity was associated with poor attention performance (β = -0.18).

Conclusion: Low retinal vascular complexity of the right or left eye may be differentially associated with cognitive domains in community-dwelling older adults over two years. The retinal vascular D_f of either eye may be served as a screening tool for detecting cognitive impairment in the preclinical phase of dementia.

Keywords: Cognition; Cohort study; Older adults; Retinal vessels.

MeSH terms

Aged
Cognition
Cognitive Dysfunction* / epidemiology
Fractals*
Humans
Independent Living
Prospective Studies