Retinal abnormalities and AMD associated with hypertension and pulse pressure

Retinal abnormalities in older people without diabetes are related to hypertension. Higher blood and pulse pressure are also associated with an increased incidence of macular abnormalities, including wet and dry age-related macular degeneration (AMD). These are the major findings of two studies appearing in the April issue of Ophthalmology, the clinical journal of the American Academy of Ophthalmology, the Eye M.D. Association.

The first study, assessing more than 2,000 men and women without diabetes, found retinal abnormalities in older people who do not have diabetes are related to high blood pressure, and retinopathy is associated with coronary heart disease, stroke, and carotid artery thickening. However, these conditions are distinct from atherosclerosis, a common form of hardening of the arteries.

According to Tien Yin Wong, FRCSE, MD, PhD, lead author of the Cardiovascular Health Study, “These changes may be markers for blood and small-vessel diseases of the brain, and have been shown to predict stroke independently of standard risk factors. Thus, patients with these changes may benefit from a full cardiovascular assessment.” Dr. Wong is assistant professor at National University of Singapore and visiting assistant professor at University of Wisconsin-Madison.

The second study, part of the Beaver Dam Eye Study, found higher systolic blood pressure – the higher pressure when the heart contracts – was associated with the 10-year incidence of loss or degeneration of pigment cells that nourish the retina’s visual cells and with wet age-related macular degeneration. It also found higher pulse pressure, the difference between the higher (systolic) and lower (diastolic) blood pressure, was associated with progression of age-related macular degeneration with loss of retinal pigment cells, release of pigment into the rest of the retina, and the development of wet age-related macular degeneration.

Ronald Klein, MD, MPH, lead author of this study and professor of ophthalmology at the University of Wisconsin-Madison, explained, “Though this study shows that hypertension is associated with the development of advanced age-related macular degeneration, there is a need for further study to see whether the tight control of blood pressure will reduce the incidence of this form of retinal disease.”

Academy spokesperson Paul Sternberg, Jr., MD, professor and chairman of the Department of Ophthalmology and Visual Sciences at Vanderbilt University, said, “These studies show that the eye provides a window to visualize blood vessel abnormalities directly, allowing us to identify patients who are at higher risk for vascular diseases affecting the coronary, carotid, and cerebrovascular arteries.”

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The first study was supported by a grant from the National Heart, Lung and Blood Institute, National Institutes of Health, and the second study was supported by grants from the National Institutes of Health and from Research to Prevent Blindness.

The American Academy of Ophthalmology is the world’s largest association of eye physicians and surgeons–Eye M.D.s–with more than 27,000 members worldwide. For more information about eye health care, visit the Academy’s partner Web site, the Medem Network, at www.medem.com/eyemd. To find an Eye M.D. in your area, visit the Academy’s Web site at www.aao.org.