Cholesterol-Lowering Statin Drugs and Aspirin Show Protection Against Wet AMD
Vision scientists are working hard to find a way to prevent wet age-related macular degeneration (AMD) and its associated blindness. A new report puts statins and aspirin in the spotlight. Statins are drugs designed to reduce cholesterol in the blood and, according to the research, reduced the risk of developing the wet form of AMD. Aspirin, a type of nonsteroidal anti-inflammatory drug, also reduced the risk of developing wet AMD.
The report appeared in the April 2003 issue of the American Journal of Ophthalmology (AJO). Statins lower cholesterol levels in the body by controlling its rate of production. Five common statin drugs on the market in the United States are lovastatin, simvastatin, pravastatin, fluvastatin, and atorvastatin. Not only are statins instrumental in controlling cholesterol, but they also appear to lower the risk of stroke and Alzheimer's disease.
Statin and aspirin users had less wet AMD
In AJO, the researchers, from the University of California San Francisco and the Loma Linda University, report the results of their retrospective (meaning that the researchers got their data from past medical records of patients) study of 326 people with various forms of AMD. People who used statins, they found, were half as likely to have their dry AMD progress to the wet form, and people on aspirin were about 40% less likely to develop wet AMD.
Dry AMD is the less dangerous and more common form of AMD. In about 10 to 15% of people with dry AMD, the condition progresses to the wet form and blindness. Wet AMD forms as abnormal blood vessels grow under the portion of the retina called the macula. The macula is responsible for clear, central vision.
"The results of this study are exciting," says Gerald J. Chader, Ph.D., chief scientific officer of the Foundation Fighting Blindness, "and FFB is pleased to have been one of the funders of the research. Additional work is warranted to understand dosing and mechanism of action of both the statins and aspirin."
Mechanism of action is not fully understood, but could possibly be related to an anti-inflammatory action; to a reduction in damage to cells of the retina (RPE cells take up cholesterol and high levels of cholesterol may be toxic); to less blockage of blood vessels (because of lower cholesterol levels) that ordinarily supply the retina, resulting in a halt to the growth of abnormal blood vessels to compensate; or to a combination of factors. The anti-inflammatory argument is persuasive. An anti-inflammatory action of aspirin is one of its cardinal roles and statins, along with their other function, also reduce inflammation. Statins prevent the production of certain proteins involved in inflammation. Other anti-inflammatory compounds like steroids (anecortave acetate (Retaane), from Alcon) and anti-oxidants also inhibit AMD.
Patients are encouraged to consult their own eye doctor for advice, and to NOT take any nutritional supplements such as these without their doctor’s approval. Not smoking is also extremely important. See another report in this issue of FFB InSight, called "Smoking and AMD."
The Foundation Fighting Blindness recommends consulting a doctor before beginning any therapy to prevent or treat AMD or any other medical condition.