An Association between Large Optic Cupping and Total and Regional Brain Volume: The Women’s Health Initiative (WHI)

Abstract

Purpose : To investigate the relationships between optic nerve cupping and total and regional brain volumes.

Methods : This is a secondary data analysis of women, aged 65 to 79, enrolled in a randomized clinical trial of postmenopausal hormone therapy. Women, aged 65+ without glaucoma in the WHI Sight Examination Study with cup-to-disc ratio (CDR) measurements and MRI-based total and regional brain volumes from the WHI Memory Study were included. Large CDR was defined as 0.6 or greater in either eye. Generalized estimating equation (GEE) models were used to account for intra-brain correlations between within right and left sides. Final analysis was adjusted for demographic, clinical characteristics, and the total brain volume (for regional analyses).

Results : Final analyses included 474 women: the mean age ± SD was 69.2 ± 3.6 years; 92.6% of subjects were white. 34 of 474 (7.2%) women had large CDR. With control for total brain volume, demographic, and clinical characteristics, lateral ventricle volume was 3.00 cc larger for those with large CDR compared to those without large CDR (95% CI: (0.02, 5.98), p-value=0.048) (Table 1). Controlling for demographic and clinical characteristics and excluding total brain volume, frontal lobe volume was 4.77 cc lower for those with large CDR compared to those without (95% CI: (-8.70, -0.85), p-value=0.017), and occipital lobe volume was 1.84 cc lower for those with large CDR compared to those without (95% CI: (-3.36, -0.32), p-value=0.018) (Table 2).

Conclusions : Our analysis suggests that in women aged 65+, large CDR is associated with lower relative total brain volume and absolute regional volume in the frontal and occipital lobes. Enlarged CDR in individuals without glaucoma may represent a sign of aging in the optic nerve and the brain.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.