A study published in the Archives of Ophthalmology finds that people with diabetes are more likely to have visual impairment than people without the disease.
Diabetes mellitus – the metabolic syndrome characterized by the body’s inability to regulate blood sugar levels – was known to afflict about 14.6 million Americans in 2005, and an additional 6.2 million suffered from the disease but remained undiagnosed. By 2050, public health experts expect that some 48.3 million will have diagnosed diabetes. “Diabetic retinopathy [damage to the retina caused by diabetes], one of the most common microvascular complications of diabetes, is considered to be one of the major causes of blindness and low vision,” write Xinzhi Zhang, M.D., Ph.D. (Centers for Disease Control and Prevention, Atlanta) and colleagues. Rates of retinal diseases have been reduced through proper management of glucose and blood pressure, but visual impairments such as cataracts and glaucoma are also likely to plague diabetic patients. Individuals suffering from diabetes also may have decreased vision due to an abnormal cornea shape.
Zhang and colleagues studied 1,237 diabetic adults (59 years old on average) and 11,767 adults without diabetes (45 years old on average) who participated in the National Health and Nutrition Examination Surveys between 1999 and 2004. The researchers gathered demographic information as well as data on visual acuity – measured before and after any correction with glasses or contacts.
The researchers found that about 11% of diabetic adults had some form of visual impairment – 3.8% uncorrectable and 7.2% correctable. However, 5.9% of participants without diabetes had some form of visual impairment -1.4% uncorrectable and 4.5% correctable. “People with diabetes were more likely to have uncorrectable vision impairment than those without diabetes, even after controlling for selected other factors,” write the researchers. “Our findings also suggest a strong association between visual impairment (correctable and uncorrectable) and older age, member of racial/ethnic minorities, lower income and lack of health insurance, all independent of diabetes status.”
“The high prevalence of visual impairment among people with diabetes indicates a need for diverse public health strategies to reduce the burden of both correctable and uncorrectable visual impairment,” conclude Zhang and colleagues. “It is important to identify and pursue ways to increase access to eye care for everyone and to correct visual impairment, where possible, to diminish morbidity and mortality due to impaired vision.”
Diabetes Mellitus and Visual Impairment
Xinzhi Zhang, MD, PhD; Edward W. Gregg, PhD; Yiling J. Cheng, MD, PhD; Theodore J. Thompson, MS; Linda S. Geiss, MA; Michael R. Duenas, OD; Jinan B. Saaddine, MD, MPH
Archives of Ophthalmology (2008); 126[10]: pp. 1421-1427.
Written by: Peter M Crosta