NHANES data show increased prevalence of vision loss, impairment among adults with diabetes

Data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) confirm that vision loss is significantly more common among adults with diabetes than it is among adults without diabetes. Researchers with the Centers for Disease Control and Prevention used NHANES data to determine the prevalence and correlates of vision impairment among U.S adults with and without diabetes. Based on data from 13,004 survey participants, the research team estimated the prevalence of...

Data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) confirm that vision loss is significantly more common among adults with diabetes than it is among adults without diabetes.

Researchers with the Centers for Disease Control and Prevention used NHANES data to determine the prevalence and correlates of vision impairment among U.S adults with and without diabetes. Based on data from 13,004 survey participants, the research team estimated the prevalence of presenting (correctable or uncorrectable), correctable, and uncorrectable vision impairment among Americans aged 20 years or older.

The findings suggested that people with diabetes have a 60% higher prevalence of correctable vision impairment and a 170% higher prevalence of uncorrectable vision impairment relative to those without diabetes.

Approximately 11% of Americans with diabetes had some form of vision impairment (9.7% moderate and 1.4% severe), including 7.2% with correctable impairment and 3.8% with uncorrectable impairment (2.9% moderate and 1.0% severe). Among those without diabetes, the prevalence of vision impairment was 5.9% (5.1% moderate and 0.9% severe), including 4.5% with correctable impairment and 1.4% with uncorrectable impairment (1.2% moderate and 0.3% severe).

The risk of uncorrectable vision impairment remained significantly associated with diabetes, even after controlling for age, sex, marital status, race/ethnicity, educational level, income, health insurance, high blood pressure, smoking, and body mass index (OR, 1.49; 95% CI, 1.01-2.20).

Although diabetes was also associated with correctable vision impairment in an age-adjusted analysis, this association was not significant in the fully adjusted model.

Other factors that were independently associated with vision loss included older age, nonwhite race/ethnicity, lower income, and lack of health insurance.

NHANES does not include the institutionalized nursing home population, which may have led to an underestimate of vision impairment prevalence generally, the researchers noted.

They added that several other factors might have contributed to an underestimation of vision impairment, including the fact that participants who were completely blind, unable to see in both eyes, or had a severe infection in one or both eyes were excluded from vision examination.

"Our findings underscore the importance of the use of an annual comprehensive eye examination for people with diabetes," the authors concluded, adding that an annual comprehensive eye examination would help clinicians identify risk factors for uncorrectable VI, detect diabetic retinopathy and other ocular conditions at their early stages, and ensure appropriate and continuous eye care, thus prevent or delay permanent vision loss. (Zhang X, et al. Arch Ophthalmol 2008;126:1421-1427.)