Association Between Neurocognitive Decline and Visual Field Variability in Glaucoma

Abstract

Visual field variability may impair detection of glaucoma progression over time. Despite the possible overlap between neurocognitive disorders and glaucoma in older individuals, no study has investigated the association between cognitive changes and visual field variability. To evaluate the association between global neurocognitive impairment and visual field variability in patients diagnosed as having glaucoma or glaucoma suspects. This prospective observational cohort study was conducted at the Visual Performance Laboratory, University of California, San Diego. The study involved 211 eyes of 115 patients followed up for a mean (SD) period of 2.5 (0.8) years, ranging from 1.2 to 4.7 years. Data were obtained during the period extending from March 2011 to April 2015, with data analysis conducted from November 2015 to May 2016. Association between cognitive decline and visual field variability. Patients were monitored with standard automated perimetry (SAP) and had longitudinal assessment of cognitive ability using the Montreal Cognitive Assessment (MoCA). Visual field variability was estimated by the SD of the residuals of ordinary least squares linear regressions of SAP mean deviation (MD) values over time. Linear regression models were used to investigate the association between cognitive decline and visual field variability, adjusting for potentially confounding factors. Among the 115 patients, the mean (SD) age at baseline was 67.4 (10.1) years, 63 were men (54.8%), and 86 were white (74.8%). There was a statistically significant association between change in MoCA scores and visual field variability over time. In a univariable model, a 5-point decline in MoCA score was associated with an increase of 0.18 dB in the SD of residuals of SAP MD (R2 = 4.3%; 95% CI, 0.06-0.30; P = .003). In a multivariable model adjusting for baseline MoCA score, mean SAP MD, age, sex, race/ethnicity, educational level, income, and number of SAP tests, each 5-point decline in MoCA score was associated with an increase of 0.23 dB in the SD of residuals of SAP MD (95% CI, 0.11-0.35; P < .001). Cognitive decline was associated with increased visual field variability during follow-up. These findings suggest that screening and monitoring of cognitive dysfunction may be important in the assessment of visual field progression in the context of glaucoma.