Loss of vision may be associated with cognitive function impairment in older people, according to a study by researchers supported in part by National Institute on Aging.

The investigators sought to determine which factor – declining vision or cognitive function – contributed more to the association over time. They identified declining vision as having a greater association with cognitive deterioration than the reverse. Study results appeared in JAMA Ophthalmology online on June 28, 2018.

Visual impairment affects almost 3 million older adults in the United States. This can significantly affect physical and psychological health, resulting in reduced quality of life. The prevalence of blindness and visual impairment increases with age, particularly among people aged 75 and older.

For this research, Diane Zheng of the University of Miami and colleagues analyzed data from the Salisbury Eye Evaluation Study, a longitudinal study that enrolled more than 2,500 participants aged 65-84 in the Salisbury area of Maryland. The study team used the Early Treatment Diabetic Retinopathy Study chart to measure visual acuity, and the Mini-Mental State Exam (MMSE) to measure cognitive function; participants were assessed in four rounds between 1993 and 2003.

The percent of participants with MMSE scores indicating cognitive impairment increased from 11% at baseline to 20.6% in the fourth round. Visual impairment was associated with poor cognitive function both cross-sectionally and longitudinally. Worsening vision had a stronger association with declining cognition than the reverse. Researchers noted maintaining good vision may be an important strategy for reducing age-related cognitive decline.

For details, see Zheng, D. et al. (2018). Longitudinal associations between visual impairment and cognitive functioning: The Salisbury eye evaluation study. JAMA Ophthalmology, 136(9), 989-995. doi:0.1001/jamaophthalmol.2018.2493