A missed prevention opportunity
The sample included 16,690 participants (54% were women, 51.5% were at least age 65, 80.2% were White, 10.6% were Black, 9.2% were other).
In total, the 12 potentially modifiable risk factors used in the researchers’ model were associated with an estimated 62.4% of dementia cases in the United States, with hypertension as the most prevalent risk factor with the highest weighted PAF.
A new focus for prevention
Commenting for this article, Suzann Pershing, MD, associate professor of ophthalmology, Stanford (Calif.) University, called the study “particularly important because, despite growing recognition of its importance in relation to cognition, visual impairment is often an underrecognized risk factor.”
The current research “builds on increasingly robust medical literature linking visual impairment and dementia, applying analogous methods to those used for the life course model recently presented by the Lancet Commission to evaluate potentially modifiable dementia risk factors,” said Dr. Pershing, who was not involved with the study.
The investigators “make a compelling argument for inclusion of visual impairment as one of the potentially modifiable risk factors; practicing clinicians and health care systems may consider screening and targeted therapies to address visual impairment, with a goal of population health and contributing to a reduction in future dementia disease burden,” she added.
In an accompanying editorial), Jennifer Deal, PhD, department of epidemiology and Cochlear Center for Hearing and Public Health, Baltimore, and Julio Rojas, MD, PhD, Memory and Aging Center, department of neurology, Weill Institute for Neurosciences, University of California, San Francisco, call the findings “an important reminder that dementia is a social problem in which potentially treatable risk factors, including visual impairment, are highly prevalent in disadvantaged populations.”
The editorialists noted that 90% of cases of vision impairment are “preventable or have yet to be treated. The two “highly cost-effective interventions” of eyeglasses and/or cataract surgery “remain underused both in the U.S. and globally, especially in disadvantaged communities,” they wrote.
They added that more research is needed to “test the effectiveness of interventions to preserve cognitive health by promoting healthy vision.”
The study was supported by grants from the National Institute on Aging, the National Institutes of Health, and Research to Prevent Blindness. The investigators reported no relevant financial relationships. Dr. Deal reported having received grants from the National Institute on Aging. Dr. Rojas reported serving as site principal investigator on clinical trials for Eli Lilly and Eisai and receiving grants from the National Institute on Aging. Dr. Pershing is a consultant for Acumen, and Verana Health (as DigiSight Technologies).
A version of this article first appeared on Medscape.com.