Serum low-density lipoprotein cholesterol level is strong risk factor for acquired color vision impairment in young to middle-aged Japanese men: The Okubo Color Study Report 2

Objective: To investigate associations between blood low-density lipoprotein cholesterol (LDL-C) levels and the prevalence of acquired color vision impairment (ACVI) in middle-aged Japanese men. Methods: Participants in this cross-sectional study underwent color vision testing, ophthalmic examination, a standardized interview and examination of venous blood samples. Ishihara plates, a Lanthony 15-hue desaturated panel, and Standard pseudoisochromatic Plates part 2 were used to examine color vision ability. The Farnsworth-Munsell 100-hue test was performed to define ACVI. Smoking status and alcohol intake were recorded during the interview. We performed logistic regression analysis adjusted for age, LDL-C level, systemic hypertension, diabetes, cataract, glaucoma, overweight, smoking status, and alcohol intake. Adjusted odds ratios for four LDL-C levels were calculated. Results: A total of 1042 men were enrolled, 872 participants were eligible for the study, and 31 subjects were diagnosed with ACVI. As compared to the lowest LDL-C category level (<100. mg/dl), the crude OR of ACVI was 3.85 (95% confidence interval [CI], 1.24-11.00) for the 2nd highest category (130-159. mg/dl), and 4.84 (95% CI, 1.42-16.43) for the highest level (≥160. mg/dl). The multiple-adjusted ORs were 2.91 (95% CI, 0.87-9.70) for the 2nd highest category and 3.81 (95% CI, 1.03-14.05) for the highest level. Tests for trend were significant (P<. 0.05) in both analyses. Conclusions: These findings suggested that the prevalence of ACVI is higher among middle-aged Japanese men with elevated LDL-C levels. These changes might be related to deteriorated neurologic function associated with lipid metabolite abnormalities.