Decreased visual acuity is related to thinner cortex in cognitively normal adults: cross-sectional, single-center cohort study

Table 1 Baseline characteristics of participants in each visual acuity (VA) group^a (total n = 2756)

	Bad (n = 159)	Fair (n = 1256)	Good (n = 1341)	p^b
	Bad (n = 159)	Fair (n = 1256)	Good (n = 1341)	Overall	Bad vs fair	Bad vs good	Fair vs good
Age (years)	67.4 ± 7.6	64.9 ± 7.0	61.4 ± 6.6	< 0.001	< 0.001	< 0.001	< 0.001
Sex (male, %)	54 (34.0)	543 (43.2)	786 (58.6)	< 0.001	0.026	< 0.001	< 0.001
Education (years)	10.2 ± 5.1	12.2 ± 4.4	13.6 ± 3.6	< 0.001	< 0.001	< 0.001	< 0.001
Hypertension (%)	82 (51.6)	620 (49.4)	547 (40.8)	< 0.001	0.600	0.009	< 0.001
Diabetes (%)	34 (21.4)	198 (15.8)	206 (15.4)	0.143	0.071	0.050	0.777
Dyslipidemia (%)	41 (25.8)	418 (33.3)	420 (31.3)	0.132	0.057	0.153	0.286
ICV (mL) × 10⁵	13.3 ± 1.5	13.4 ± 1.2	13.8 ± 1.2	< 0.001	0.136	< 0.001	< 0.001
MMSE^c	26.4 ± 0.3	27.6 ± 0.1	28.2 ± 0.1	< 0.001	< 0.001	< 0.001	< 0.001
VA (logMAR)	0.49 ± 0.13	0.16 ± 0.07	− 0.02 ± 0.05	< 0.001	< 0.001	< 0.001	< 0.001
Total cortical thickness (× 10⁻¹mm)	60.16 ± 2.42	60.81 ± 2.29	61.16 ± 2.13	< 0.001	0.001	< 0.001	< 0.001

ICV intracranial volume, MMSE Mini-Mental state examination, logMAR -log (Snellen visual acuity)
^aGrouped by VA in better-seeing eye: bad = VA ≤ 20/40, fair = 20/40 < VA ≤ 20/25, and good = VA > 20/25 (VA was presented in the Snellen system). Numerical continuous parameters were described as mean ± standard deviation, and categorical parameters were described as total numbers (percentages)
^bResults from analysis of variance (ANOVA) with Bonferroni post hoc test for continuous variables (total cortical thickness, age, education, ICV, MMSE) and Pearson’s chi-squared test for binary variable (sex, hypertension, diabetes, dyslipidemia)
^cMMSE has a missing value: 11 subjects in the bad VA group, 54 subjects in the fair VA group, and 58 subjects in the good VA group

ISSN: 1758-9193