A new study projects that nearly half of all adult Hispanic/Latino individuals in the United States with diabetes have some type of diabetic retinopathy, a degenerative disease affecting vision. Generally, the longer the duration of their diabetes, the higher the prevalence of diabetic retinopathy. In addition, nearly 10 percent of Hispanics/Latinos in this study had early age-related macular degeneration (AMD), a condition that can lead to a reduction in central vision. These research findings provide an estimate of the burden of eye disease among Hispanics. They also can assist health care policy makers to plan eye care and rehabilitative services and to estimate the costs of diabetic retinopathy and AMD related to vision loss and blindness.
Diabetic retinopathy is a leading cause of blindness among working-age Americans, and macular degeneration is a leading cause of blindness among older Americans. Because vision loss can be reduced with regular comprehensive eye exams and timely treatment, there is an increasing need to implement culturally appropriate programs to detect and manage eye diseases in this population.
These results, from two research papers related to the Los Angeles Latino Eye Study (LALES), appear in the July 2004 issue of the journal Ophthalmology. The first three papers were published in the June issue. Two additional papers will be published in the August issue. The studies were funded by the National Eye Institute (NEI) and the National Center on Minority Health and Health Disparities (NCMHD), two components of the National Institutes of Health. Other funding support was provided by Research to Prevent Blindness, Inc.
LALES is the largest, most comprehensive epidemiological study of visual impairment in Hispanics conducted in the U.S. Researchers gave a detailed health interview and clinical examination to 6,357 Latinos, primarily Mexican-Americans, aged 40 and older from six census tracts in Los Angeles. The interview included an assessment of demographic, behavioral, and ocular risk factors and assessed participants' health-related and vision-related quality of life. The study investigators performed a comprehensive eye examination on each of the participants, looking at visual acuity, intraocular pressure, and visual fields. They also performed blood tests for diabetes and took photographs of the back of the eye.
Of the 1,263 participants diagnosed with diabetes, nearly half had diabetic retinopathy. In addition, more than 10 percent of participants with diabetes had macular edema, or fluid buildup in the back of the eye. Sixty percent of those with macular edema had cases severe enough to require laser treatment.
Overall, six percent of people with diabetes were visually impaired (defined as best-corrected visual acuity worse than 20/40 in the better-seeing eye), and more than eight percent needed laser treatment to prevent visual loss. Among those with diabetes, one in five individuals were newly diagnosed during the LALES clinic exam, and 23 percent of these individuals had diabetic retinopathy. Researchers also found that participants who had diabetes for 15 years or more were more than three times as likely to have diabetic retinopathy, and more than 23 times as likely to have severe diabetic retinopathy, than those newly diagnosed. Latinos appear to have a higher rate of more severe vision-threatening diabetic retinopathy than whites. There are no good data on prevalence of diabetic retinopathy among blacks in the U.S.
With regard to macular degeneration, nearly ten percent of participants had signs of early AMD. This increased five-fold with age from more than six percent in those in their 40s to nearly 30 percent in those aged 80 and older. The overall prevalence of advanced AMD was 0.5 percent of this population and was more than eight percent in those aged 80 and older. Although there were few cases of advanced AMD, Latinos had early AMD at rates nearly twice as high as blacks. Early and advanced AMD rates were comparable to rates seen in whites. Of all participants with AMD, only 57 percent reported ever visiting an eye care practitioner and only 21 percent had done so within the last year.
The NEI recommends a comprehensive dilated eye exam at least once every two years for African Americans over age 40 and everyone over age 60, and at least once a year for all people with diabetes.
Citations Varma R, Torres M, Peña F, Klein R, Azen SP, Los Angeles Latino Eye Study Group. Prevalence of Diabetic Retinopathy in Adult Latinos: The Los Angeles Latino Eye Study. Ophthalmology. 2004 Jul. PubMed Varma R, Fraser-Bell S, Tan S, Klein R, Azen SP, Los Angeles Latino Eye Study Group. Prevalence of Age-Related Macular Degeneration in Latinos: The Los Angeles Latino Eye Study. Ophthalmology. 2004 Jul. PubMed