Study links cardiovascular risk factors to visual impairment in Latinos

In the U.S., Hispanic/Latino populations are disproportionately at risk for eye diseases like glaucoma and diabetic retinopathy, or vision loss tied to diabetes. But the association between heart and eye health in Hispanic/Latino people remains under-researched, said Dr. Charlotte Joslin, UIC professor of ophthalmology.

In a new study published in JAMA Network Open, Joslin examined vision and cardiovascular health data from more than 3,000 Hispanic/Latino adults. The results indicate an association between cardiovascular disease risk factors, like diabetes, and visual impairment.

"Normally, we tend to think of eye health as distinct from the rest of the body. These results reveal a relationship between cardiovascular disease risk factors and visual impairment," said Joslin, who is also affiliated with the epidemiology and biostatistics department in the School of Public Health.

In 2019, Joslin received $9.7 million from the National Eye Institute to fund the Study of Latinos "Ojos" study, or SOL Eye study, which examined eye disease in Hispanic/Latino communities. Eventually, the grant would reach $10.6 million.

The six-year study looked at data from 3,294 adults aged 40 and older (about 60 years old on average) in Chicago and Miami. All participants belong to the Hispanic Community Health Study/Study of Latinos, a cohort of 16,000 participants that is the basis for broad research on Hispanic/Latino populations and health, funded by the National Institutes of Health.

Participants in Joslin's study identified as Central American, Cuban, Mexican, Puerto Rican, South American or another unspecified background. Each participant received state-of-the-art eye examinations.

First, we measure the vision with which participants walk into the office: their day-to-day eyesight with whatever lenses they normally use or don't use. Then, we determine the best each participant's vision could possibly be with the proper corrective eyewear."

Dr. Charlotte Joslin, UIC professor of ophthalmology

The latter metric can help identify eye disease, specifically in patients who are still visually impaired despite corrective eyewear. The researchers also tracked when corrective lenses were outdated, incorrect or absent altogether.

Participants were also assessed for diabetes, high cholesterol, obesity, smoking and high blood pressure - all risk factors for cardiovascular disease.

Joslin said participants with more risk factors - three or four, perhaps, instead of one or none - were likelier to be visually impaired. Previous studies have linked single conditions, such as diabetes, to visual impairments, but none have acknowledged the effect of compounded factors.

"If you were just diagnosed with diabetes, that's one risk factor. But many of these risk factors tend to go together. This study tells us that people who have three risk factors - for example, diabetes, high cholesterol and hypertension - have a much greater risk for visual impairment than those with just one risk factor, such as diabetes," Joslin said.

Results also revealed differences among participants with different backgrounds. For example, men who identified as Mexican were four to six times more likely to be visually impaired than other groups.

"We cannot treat everyone the same. Recognizing heterogeneity across Hispanic/Latino backgrounds is so important for targeted treatments and care," Joslin said.

Visual impairment was also associated with lower socioeconomic status, educational level and income, a preference for Spanish versus English language and limited access to healthcare.

Joslin said the associations between cardiovascular disease risk factors and eye health identified in this study are not causal and must be contextualized within the experiment; for example, this study's focus on Hispanic/Latino adults and the tendency of healthier individuals to volunteer for scientific studies.

Additional authors from UIC include Angie Wang, Dr. Lawrence J. Ulanski, Dr. Thasarat Vajaranant, Michael Stewart, Giselle Gutierrez Savoy, Dr. Mehmet Cem Mocan and Dr. Martha L. Daviglus. The Hispanic Community Health Study/Study of Latinos is a collaborative study supported by grants from the National Institutes of Health to the University of North Carolina, the University of Miami, the Albert Einstein College of Medicine, UIC, Northwestern University and San Diego State University.