Another day, another study that finds poverty is linked to adverse and often preventable health outcomes. This time, it’s vision loss.

Last week, the Centers for Disease Control and Prevention published new data finding that poverty is significantly correlated with severe vision loss, which is defined as being blind or having serious difficulties seeing even with glasses. In examining data from the American Community Survey, researchers found that among counties in the top quartile for severe vision loss, more than 55 percent were also in the top quartile for poverty. The South is home to more than three-quarters — 77.3 percent — of U.S. counties in the top quartile for severe vision loss prevalence, followed by the West, the Midwest and the Northeast. More than 83 percent of the 437 counties in the top quartiles for both poverty and severe vision loss were located in the South as well. In CDC’s Morbidity and Mortality Weekly Report (MMWR), study authors Karen Kirtland, Jinan Saaddine, Linda Geiss, Ted Thompson, Mary Cotch and Paul Lee write:

Vision loss and blindness are among the top 10 disabilities in the United States, causing substantial social, economic, and psychological effects, including increased morbidity, increased mortality, and decreased quality of life. …A better understanding of the underlying barriers and facilitators of access and use of eye care services at the local level is needed to enable the development of more effective interventions and policies, and to help planners and practitioners serve the growing population with and at risk for vision loss more efficiently.

The study notes that about 4 million people ages 40 and older in the U.S. are blind or have vision loss, and the data suggests this number will climb to 10 million by 2050. According to Prevent Blindness America, the economic toll of vision loss and eye disorders was $139 billion in 2013, making them among the nation’s costliest health conditions. Unfortunately, the Affordable Care Act only requires that insurers participating in the new marketplace cover pediatric vision care — adult vision coverage is optional (consumers can purchase a stand-alone vision plan, but such plans don’t qualify for subsidies, putting them out of reach for many Americans). Medicare only covers comprehensive dilated eye exams for people with diabetes and those at high risk of glaucoma.

The MMWR study examined Census data from 2009–2013 to calculate county-level estimates of severe vision loss and poverty among adults ages 18 years old and older. The authors noted that flushing out this data at the county level, as opposed to depending on existing state- and national-level data, can be extremely helpful, as related policies and interventions are often developed and put into action at the community level. Among the more than 3,100 counties studied, researchers found that eight states had at least 6 percent of their counties in the top quartiles for both severe vision loss and poverty — those states were Alabama, Arkansas, Georgia, Kentucky, Mississippi, North Carolina, Tennessee and Texas.

Overall, researchers found “distinct geographic patterns” to severe vision loss, with the South home to a disproportionately high prevalence of people living with serious vision problems. County-level prevalence of severe vision loss varied across U.S. counties, ranging from less than 1 percent to 18.4 percent. None of the counties in the top quartile for both severe vision loss and poverty were located in the Northeast.

While the researchers noted that their study has some limitations, such as being based on self-reported data, their results do line up with previous studies on the associations between vision loss and poverty. For example, a 2013 study published in JAMA Ophthalmology found that the use of eye care services “decreased progressively” as socioeconomic disadvantage went up. In that study, researchers noted that among Americans who reported limiting their medical care visits during the recent recession, eye care was one of the most commonly skipped services. The JAMA study stated that access to regular eye care is needed to reduce the burden of vision loss among patients with age-related eye disease; however, people living in low-income households face real barriers, such as an inability to pay, high insurance deductibles and limited access to eye doctors.

Of course, widening access to affordable preventive vision care services would be an ideal way to narrow the eye health gap. But public health workers have a role in preventing and lessening vision loss as well. The MMWR study recommends that officials in counties with high rates of severe vision loss offer education on behaviors that support optimal eye health, such as maintaining a healthy weight, not smoking, using proper eye safety precautions and learning about one’s family eye health history.

The MMWR study states: “Further investigations are needed to better understand the sociodemographic disparities of vision loss, how to minimize risk factors associated with vision loss, and how to improve access and use of eye care services.”

To read a full copy of the study, visit MMWR.

The above video courtesy Prevent Blindness America.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.