Dementia Prevalence May Be Reduced by Improving Vision

According to a recent study published in the JAMA Neurology, dementia prevention is a high priority, given the large impact of dementia on the well-being of individuals and society. The number of older adults with dementia in the US and globally is projected to increase as a result of population ageing and growth. Thus, it is vital to identify potentially modifiable dementia risk factors. Vision impairment has been identified as a risk factor for accelerated cognitive decline and incident dementia. An estimated 90% of vision impairment is preventable or has yet to be treated. Nevertheless, vision impairment has not been included in the dominant life-course model of dementia risk factors, developed by the Lancet Commission, used to shape public health policy and research priorities.

Study Overview

A study was conducted to strengthen an existing model of potentially modifiable dementia risk factors through the inclusion of vision impairment and to estimate the contributions of those risk factors in the US population. This was a population-based, cross-sectional study using data from the 2018 round of the Health and Retirement Study. Analyses were conducted from March 11 through September 24, 2021. The study population was a probability sample of US adults aged 50 years and older.

Results

• The probability sample from the Health and Retirement Study included 16,690 participants.
• The 12 dementia risk factors in the PAF model were associated with an estimated 62.4% of dementia cases in the US.
• The risk factor with the highest weighted PAF for dementia was hypertension (12.4%).
• The PAF of vision impairment was 1.8%, suggesting that more than 100,000 prevalent dementia cases in the US could potentially have been prevented through healthy vision.

Thus, existing life-course models of potentially modifiable dementia risk factors, such as the Lancet Commission's, may consider including vision impairment. Since a large majority of vision impairment can be treated with cost-effective but underused interventions, this may represent a viable target for future interventional research that aims to slow cognitive decline and prevent incident dementia.

Reference

Addition of Vision Impairment to a Life-Course Model of Potentially Modifiable Dementia Risk Factors in the US by Joshua R. Ehrlich, et al. published in the JAMA Neurology.

DOI: 10.1001/jamaneurol.2022.0723

Keywords

• Dementia
• Prevalence
• Reduced
• Improving
• Vision
• Joshua R. Ehrlich
• Jenna Goldstein
• Bonnie K. Swenor
• Heather Whitson
• Kenneth M. Langa
• Phillip Veliz