When it comes to glaucoma, risk reduction is a simple matter of damage control. Aside from following healthy-lifestyle recommendations, we have little control over whether we develop glaucoma.
If your vision care provider discovers you have elevated eye pressure, he or she may label you a "glaucoma suspect" and will be monitoring you closely to check your eye pressure and test for damage to your optic nerve.
Researchers have identified a number of factors that indicate you are at increased risk of developing glaucoma:
Nonmodifiable risk factors
- Advancing age. Adults over age 60 are at increased risk of developing glaucoma. Elderly adults over age 80 have three to ten times the risk of developing glaucoma as those in their 40s.
- Ethnicity. People of certain ethnic backgrounds have a greater risk of developing glaucoma and of having vision loss associated with the disease:
- Black Americans, in particular, have a magnified risk. They’re five times more likely than whites to be diagnosed with glaucoma and four times more likely to lose their sight to the disease.
- Hispanic Americans also have an enhanced risk for open-angle glaucoma.
- Asian Americans have a heightened risk of angle-closure glaucoma
- Family history. Having an immediate family member with glaucoma - that is, a parent, child, brother, or sister who has the disease, boosts your risk of developing it as well.
- Poor eyesight. Nearsighted (myopic) people have a two- to three-fold risk of glaucoma compared with non-nearsighted people. Farsighted people have recently been shown to have a steeper risk as well. People with either of these conditions, which vision care providers call refractive errors, should be monitored carefully.
- Thin corneas. The human cornea is so thin, it’s measured in microns. One study showed that people with thin corneas - 555 microns or less - have three times the risk of developing glaucoma, compared with people whose corneas measure 588 microns or more. Researchers are working to confirm this intriguing finding, but it’s likely that having thin corneas will prove to be an independent risk factor for glaucoma.
Modifiable risk factors
- Elevated eye pressure. Calling elevated eye pressure a risk factor for glaucoma is like saying that having elevated blood sugar is a risk factor for diabetes. In other words, this risk factor is so closely associated with the disease itself that it’s difficult to distinguish one from the other.
On the other hand, the human body is idiosyncratic. An eye pressure that would destroy the optic nerve in one person might do no damage at all in another. Some folks can just tolerate a higher pressure with no ill effects. If your eye pressure is high, but you have no evidence of the disease, you should receive careful follow-up exams.
- Having diabetes. Researchers believe that if you have diabetes, you’re twice as likely to develop glaucoma, although some studies are beginning to question that conclusion. Likewise, people who have glaucoma are more likely to develop diabetes.
Systemic high blood pressure (as opposed to high eye pressure) is thought to coexist frequently with glaucoma. Scientists are still investigating the reason for this. Similarly, an unexplained association has been demonstrated between glaucoma and the endocrine disorder hypothyroidism.
- Use of corticosteroid medications. Certain corticosteroid medications, such as those found in some asthma inhalers, can block the ducts through which the aqueous fluid exits the eye. The optic nerve can be damaged if the drug is not discontinued promptly.
- Eye injuries. A type of glaucoma called traumatic glaucoma is associated with eye injuries. Such injuries can be caused by blunt trauma, such as being punched in a fight or being struck with a hockey puck, tennis racket, rock, or even a snowball or baton. In everyday terms, it’s the kind of injury that gives you a black eye.
Penetrating trauma occurs when a sharp object penetrates the eye. Objects that cause penetrating trauma include knives, metal fragments, BB gun pellets, glass, plastic, and even animal bites or scratches.
Doing damage control requires knowing whether you have glaucoma and, if so, keeping your eye pressure within the normal range to keep your optic nerve cells intact. Be sure to have your eyes examined at the recommended intervals. If your eye pressure is elevated, your provider may use a special tool to determine your risk that the condition will progress to glaucoma. If it does, following your prescribed treatment regimen, including using your eye drops as instructed, will help preserve your vision.
- Glaucoma Screening. If you have diabetes or a family history of glaucoma, or if you are a black American age 50 or older or a Hispanic American age 65 and older, Medicare will cover a comprehensive dilated eye exam every year to check for diseases such as glaucoma, diabetic retinopathy, macular degeneration, and cataracts.
- Follow the recommended treatment regimen. Patients and doctors often wish there were a magic bullet that could make a disease go away. In glaucoma treatment, medicated eye drops aren’t quite a magic bullet, but they’re close. One convincing study reports that eye drops reduce eye pressure by more than 20 percent. In some patients with elevated pressure, daily use of eye drops cuts in half the risk of developing glaucoma.
Remember, vision loss from glaucoma can occur so slowly that you don’t notice it, so continue to use your eye drops as prescribed even if you think your vision is tip-top.
- Follow healthy-lifestyle recommendations to prevent diabetes and obesity. Your risk of developing type 2 diabetes doubles for every 20 percent increase over your healthy body weight. Controlling your weight, then, reduces your risk of both diabetes and glaucoma, as well as many other obesity-related diseases. You should engage in moderate-intensity aerobic activity for at least 2½ hours per week if you’re able to do so (see the 2008 Physical Activity Guidelines for Americans). Not many of us can do headstands after age 10 or so, but in case you’re tempted, be aware that such activities can raise your eye pressure temporarily.
Stock your kitchen with fresh fruits and veggies, or with canned, frozen, or dried ones if you can’t get out to the grocery store often. Aim for a low-fat, high-fiber diet consistent with the U.S. Department of Agriculture’s most recent Dietary Guidelines for Americans.
- Wear recommended eye protection. It’s not practical, of course, to wear safety goggles while playing with a cat or twirling a baton in the marching band. But those who are engaged in any activity that poses a serious threat of eye injury, such as drilling, sawing, riveting, and even lawn mowing, should wear safety glasses.
At work, pipe fitters, carpenters, and others who require protective eyewear should follow the guidelines issued by the Occupational Safety and Health Administration (OSHA). Glaucoma may develop soon after the injury or years later, so it’s important for those who have suffered such injuries to receive regular screenings.
Living with Glaucoma
Being diagnosed with glaucoma or being told you are at risk for the disease means taking responsibility for your remaining vision, in concert with your vision care professional. The usual order of things, however, is reversed. Instead of patient relying on practitioner, your vision care provider is counting on you.