Many Americans at high risk of vision loss do not have access to eye care

Data from a national survey suggest that an estimated 60 million American adults are at high risk of vision loss, according to a report published in the March issue of Archives of Ophthalmology, one of the JAMA/Archives journals. Of those adults, one in 12 cannot afford eyeglasses when needed, and about one-half do not get dilated eye examinations on a yearly basis.

In 2000, about 3.3 million Americans age 40 or older were visually impaired and more than 11 million of those age 12 and older needed glasses or contact lenses, according to background information in the article. By 2020, these numbers could increase by 50 percent or more. Eye diseases and vision problems are associated with increased illness, increased risk of death and decreased quality of life. They also are causes of falls and injuries and can lead to depression and social isolation.

Xinzhi Zhang, M.D., Ph.D., Centers for Disease Control and Prevention, Atlanta, and colleagues used data on vision from the 2002 National Health Interview Survey to estimate the number of U.S. adults at high risk of vision loss and assess factors associated with the use of eye care services. A total of 30,920 adults age 18 or older participated in the survey, designed to be representative of the entire U.S. population.

Sixteen percent of the participants were age 65 years or older, 6.5 percent had diabetes and 19.5 percent had vision or eye problems. Based on these percentages, the authors project that an estimated 61 million American adults are at high risk of serious vision loss. The researchers estimated that of those, only half visited an eye doctor in the past 12 months and half had dilated eye examination, in which eyedrops are administered to widen the pupil, allowing a more thorough inspection of the eyes. Yearly exams are recommended for those with diabetes or who are age 65 or older. About one-third of the estimated 144 million U.S. individuals not at high risk of serious vision loss visited an eye doctor and one-third had a dilated eye examination in the past 12 months.

"Among the high-risk population, the probability of having a dilated eye examination increased with age, education and income," the authors write. "The probability of receiving an examination was higher for the insured, women, persons with diabetes and those with vision or eye problems. Approximately 5 million high-risk adults could not afford eyeglasses when needed; being female, having low income, not having insurance and having vision or eye problems were each associated with such inability."

As the population ages, providing access to preventive eye care services will become a larger public health concern, the authors note. "Many conditions causing visual impairment and blindness are often asymptomatic in their early, treatable stages," they conclude. "There is substantial inequity in access to eye care in the United States. Better targeting of resources and efforts toward people at high risk may help reduce these disparities."

(Arch Ophthalmol. 2007;125:411-418. Available pre-embargo to the media at www.jamamedia.org.)

Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Women who develop age-related macular degeneration may have higher blood levels of markers related to inflammation before they begin showing symptoms of the disease. Debra A. Schaumberg, Sc.D., O.D., Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues, measured three markers of inflammation-high-sensitivity C-reactive protein, soluble intercellular adhesion molecule-1 and fibrinogen-in the blood of 27,687 women (average age 54.6) without age-related macular degeneration (AMD), a condition in which the part of the retina responsible for sharp vision begins to deteriorate. After an average of 10 years of follow-up, women who had the highest levels of these three markers in their blood were most likely to develop AMD. "Further study of the interrelationships of genetic predisposition with these factors and the possible clinical utility of the measurement of inflammatory biomarkers such as high-sensitivity C-reactive protein in the setting of AMD should be considered," the authors conclude.

In another report of a clinical trial involving 22,071 healthy U.S. male physicians age 40 to 84, taking beta carotene supplements had no effect on the risk of age-related maculopathy (ARM), diseases of the retina that include macular degeneration. William G. Christen, Sc.D., also of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues analyzed data from a clinical trial in which about half the men were randomly assigned to take 50 milligrams of beta carotene every other day and the other half to take placebo. After 12 years of follow-up, there were 162 cases of ARM among those taking beta carotene and 170 cases in the placebo group. According to the authors, these findings, together with other recent discoveries, will help in "clarifying the effects of individual antioxidant supplements and other nutrient combinations and should help endure rational clinical and public health recommendations for the prevention of ARM."

(Arch Ophthalmol. 2007;125:300-305 and 333-339. Available pre-embargo to the media at www.jamamedia.org.)

Editor's Note: Please see the articles for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. To contact Debra A. Schaumberg, Sc.D., O.D., or William G. Christen, Sc.D., call Lori J. Shanks at 617-534-1604.