Metformin has established itself as a first-line drug for type 2 diabetes. In addition to lowering blood sugar levels, this drug may extend lifespan, lower heart risk, lower high blood pressure, and provide other health benefits.
Now, researchers are also observing that metformin (sold under trade names such as Glucophage, Glumezza, and Fortamet) may also reduce the likelihood of age-related macular degeneration (AMD), the leading cause of vision loss in people over 50. The disease, which puts diabetics at higher risk, affects about 2.1 million people nationwide, according to the National Institutes of Health.
See more research on metformin and AMD
In a report presented Oct. 28 at the American Academy of Ophthalmology annual meeting, researchers in Taiwan analyzed health data for 45,524 diabetic patients taking metformin, compared with 22,681 patients not taking metformin. All participants had new-onset type 2 diabetes. A retrospective study was conducted from January 2001 to December 2013.
Scientists found that people who took metformin had about a 50 percent lower risk of developing AMD than those who didn’t take it.
“Our study reveals for the first time the preventive effect of metformin on the development of AMD,” lead researcher Yu-Yen Chen, MD, of the Taichung Veterans Affairs Hospital in Taiwan, said in a statement. “Further research is needed to determine how metformin prevents the development of AMD, but this is an interesting development for at-risk patients.” Dr. Chen was not immediately available for comment.
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Dr. Mark Frommer, an ophthalmologist at Lenox Hill Hospital in New York City who was not involved in the study, said he has seen tens of thousands of patients with diabetes and thousands of patients with macular degeneration. Because high blood sugar can cause a variety of health problems, people who are prescribed metformin tend to have some pre-existing health problems. But Dr. Frommer says, “What we don’t see very often in many metformin patients is macular degeneration, so these researchers may be on to something.”
Frommer cautions that this is a retrospective study. Although the study involved a large number of people over a long period of time, controlled studies in current patients are needed so scientists can investigate other factors such as smoking, obesity, diet and controlled use of drugs, he said.
Why might metformin help with AMD?
Inflammation and oxidative stress have long been known to play important roles in the development of both diabetes and AMD, researchers said. Oxidative stress is a disturbance in the balance between the production of harmful free radicals and the body’s ability to detoxify them.
“Given the known anti-inflammatory and antioxidant properties of metformin, it is important to propose that metformin may reduce the development of AMD,” the study authors wrote.
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What role does diabetes play?
When you have diabetes, your body is unable to allow blood sugar to reach your cells and use it for energy. Sugar that builds up in the blood destroys blood vessels that carry blood to vital organs. This increases the risk of many health problems, including heart attack and stroke. Metformin, available as a pill or liquid, helps reduce the amount of sugar the liver releases into the blood and improves the way the body processes insulin, which regulates the amount of glucose in the blood.
According to the Macular Degeneration Association, people with diabetes may be at increased risk of blindness because high blood sugar levels can damage the eyes. The Macular Degeneration Foundation of America notes that macular degeneration is the leading cause of vision loss, affecting more than 10 million Americans. This is more than cataracts and glaucoma combined.
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How macular degeneration affects vision
Macular degeneration damages a specific part of the retina called the macula. The macula captures the images we see and transmits them to the brain via the optic nerve. The National Eye Institute describes the macula as the part of the eye necessary for sharp central vision to see objects straight ahead. When the macula is destroyed, vision becomes blurry or wavy and can lead to complete vision loss. There is no known cure for macular degeneration.
According to the Macular Degeneration Foundation of America, AMD occurs more often in people over the age of 55. The authors noted that the risk of AMD was much higher in patients over 70 years of age compared to those under 50 years of age.
“With each decade of life, your chances of developing macular degeneration increase,” Frommer says. “Retinal function deteriorates with each decade of life.”
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According to research, AMD is one of the two most common retinal degenerative diseases. clinical ophthalmology. Another eye-related problem common in people with uncontrolled diabetes is diabetic retinopathy, which damages blood vessels in the retina and causes patchy vision loss. The American Diabetes Association notes that more than 60% of people have type 2 diabetes. I have some degree of retinopathy.
Chen’s team also noted that participants with hypertension, hyperlipidemia, coronary artery disease, obesity, and diabetic retinopathy were also at significantly higher risk of developing AMD.
Metformin may help reduce your risk of AMD, but the Macular Degeneration Foundation also recommends lifestyle changes such as diet, exercise, smoking cessation, and protecting your eyes from UV rays.
