According to a research letter published online July 7 in JAMA Ophthalmology, there is significant variation in the county-level prevalence of visual acuity or blindness, with a positive correlation between visual acuity loss or blindness and the percentage of the population living below the poverty level.
To create county-level prevalence estimates for visual acuity loss or blindness, Elizabeth A. Lundeen, Ph.D., M.P.H., from the U.S. Centers for Disease Control and Prevention in Atlanta, and colleagues combined different data sets.
Using information from five population-based studies, the cumulative prevalence of visual acuity or blindness was calculated by age, sex, race, and ethnicity.
The researchers observed considerable geographic variation in county-level prevalence of visual acuity loss or blindness. There was variation noted in the crude prevalence, from 0.75 to 13.16 percent in Douglas County, Colorado, and Kalawao County, Hawaii, respectively.
In Cumberland County, Maine, and Clay County, Kentucky, the standardized prevalence ranged from 0.99 to 10.88 percent, respectively. The proportion of the county's population living below the poverty level was positively correlated with the county's standardized visual acuity loss or blindness prevalence.
"Data identifying geographic variation in the prevalence of visual acuity loss can be used to guide interventions to improve eye care services, as counties with a higher prevalence of visual acuity loss may have less access to and use of eye care services," the authors concluded.