HealthDay News — The increase in incidence of serious nonrefractive vision impairment, such as cataracts and glaucoma, may be partly due to a higher prevalence of diabetes, researchers suggest.
The prevalence of nonrefractive visual impairment among U.S. adults aged 20 years and older increased 21% from 1999 to 2008 (P=0.03), and coincided with an increase in patients who had a diabetes diagnosis for 10 or more years (P=0.02), according to Fang Ko, MD, of the Wilmer Eye Institute at the Johns Hopkins University School of Medicine in Baltimore, and colleagues.
The odds ratio for developing a nonrefractive eye disease among this population increased from 1.93 in 1999 to 2002 (95% CI 1.15 to 3.25) to 2.67 in 2005 to 2008 (95% CI 1.64 to 4.37), the researchers reported in the Journal of the American Medical Association.
“If the current finding becomes a persisting trend, it could result in increasing rates of disability in the U.S. population, including greater numbers of patients with end-organ diabetic damage who would require ophthalmic care,” Fang and colleagues wrote.
Prevalence of nonrefractive visual impairment was analyzed using data from the National Health and Nutrition Examination Survey for 9,471 participants in 1999 to 2002 and for 10,480 participants in 2005 to 2008.
Participants also answered questionnaires and participated in laboratory tests and physical examinations. Information on age, sex, race, years of schooling, income, diabetes status, access to healthcare, health insurance coverage, and smoking status was gathered.
Participants in the 1999 to 2002 sample were significantly younger than the 2005 to 2008 sample (45.1 years vs. 46.7 years, P=0.005), and had a significantly lower prevalence of diabetes (6.5% vs. 8.2%, P=0.001).
Similarly, the prevalence of having a diabetes diagnosis for 10 years or more (2.8% vs. 3.6%, P=0.02) and prevalence of nonrefractive visual impairments (1.4% vs. 1.7%, P=0.03) were also lower in the 1999 to 2002 sample.
In addition to diabetes, the following factors were also associated with prevalence of nonrefractive visual impairment during both survey periods:
- Older age
- Race other than non-Hispanic white
- Less education
- Lack of health insurance at the time of the survey
- Current insulin use
Study limitations included a lack of information regarding the cause of vision loss in NHANES data and the inclusion of only a single measure of vision function and refraction, the researchers noted.
In an accompanying editorial, David Musch, PhD, MPH, and Thomas Gardner, MD, both of the University of Michigan in Ann Arbor, noted that the adverse effect of diabetes on vision “affects both performance-based measured and health-related quality of life and adds substantially to healthcare costs.”
They called for additional funding to better understand the underlying causes of diabetes and it’s complications.