Coffee and Glaucoma: “1-2 cups of coffee is probably fine, but…”

10/2/14

The Relationship Of Coffee And Glaucoma

Research shows that drinking caffeinated beverages, especially coffee, causes eye pressure to go up, even just one cup of coffee. The effect is highest in glaucoma patients and people at risk for glaucoma. However, eye pressure goes up only a small amount, so it is probably not a significant risk.
Coffee and glacoma
In some people, though, too much coffee may be causing damage. In people at risk for exfoliation glaucoma (a type of open angle glaucoma where some flake-like deposits are seen on the lens of the eye), drinking three or more cups of caffeinated coffee was associated with an increased risk of developing exfoliation glaucoma. The effect was strongest in women with a family history of glaucoma. This study doesn’t show that coffee causes glaucoma, but does suggest that drinking three or more cups of caffeinated coffee might not be good for your eyes.

One group of scientists applied caffeine eye drops directly on to healthy eyes, and they did not see any increase in eye pressure. This suggests that caffeine doesn’t appear to have a direct effect.

How can you best protect your eyes? Consider going decaffeinated or limit your caffeine consumption. If you are at higher risk for glaucoma or have been diagnosed, be sure to have regular comprehensive dilated eye exams, use medications as directed and see your eye care provider as scheduled.
For more information about glaucoma, visit www.nei.nih.gov/glaucoma.

References
The effect of caffeine on intraocular pressure: a systemic review and meta-analysis. Li M, Wang M, Guo W, Wang J, Sun X. Graefes Arch Clin Exp Ophthalmol 2011. 249(3):435-42.

Effect of caffeine on the intraocular pressure in patients with primary open angle glaucoma. Chandra P, Gaur A, Varma S. Clin Ophthalmol 2011. 5:1623-9.

The relationship between caffeine and coffee consumption and exfoliation glaucoma or glaucoma suspect: a prospective study in two cohorts. Pasquale LR, Wiggs JL, Willett WC, Kang JH. Invest Ophthalmol Vis Sci 2012. 53(10):6427-33.

Effects of caffeinated coffee consumption on intraocular pressure, ocular perfusion pressure, and ocular pulse amplitude: a randomized controlled trial. Jiwani AZ, Rhee DJ, Brauner SC, et al. Eye 2012 26(8):1122-30.

Julia Rosdahl - coffee and glaucomaJullia A. Rosdahl, MD, PhD
National Eye Health Education Program Glaucoma Subcommittee
Duke Eye Center, Duke University

Genetics and Glaucoma: Why don’t we have a genetic test for glaucoma?

9/25/14

We have known for a long time that there is a genetic component to glaucoma, since having a family history of glaucoma is one of the most important risk factors for developing the disease. Glaucoma is actually a group of diseases, including some starting at birth or in childhood, as well as the more common types that happen in adults, such as primary open angle glaucoma.dna strand - genetics and glaucoma

In some of the glaucomas of childhood, scientists can trace the cause to a single gene. For example, mutations in the gene for myocillin can cause juvenile-onset open angle glaucoma. And there are genetic tests available for some of these genes. These genetic tests, however, are helpful only for a subset of glaucoma patients. For most glaucoma patients, these tests don’t give us the answers we need.

In the types of glaucoma that happen in adults, both environmental factors and genetic factors contribute to whether or not someone develops the disease. This complex interplay of factors makes testing only one gene or a handful of genes not as helpful. For diseases like adult-onset open angle glaucoma, instead of having just one gene that is mutated and causing the disease, there are many genes involved. All these genes contain tiny differences, some potentially helpful and some potentially harmful. It is an individual’s mix of genes combined with the lifetime of complex environmental exposures, that determines whether he or she will get the disease. In the future, genetic tests that incorporate this group of genes will help doctors, patients, and families better understand their susceptibilities, and hopefully lead to prevention of vision loss from glaucoma.

Genetic testing has the potential to offer a lot of benefits, but is not without risk and unintended consequences. Genetic counselors are trained to help patients, families, and doctors navigate these areas.

For more information about glaucoma, visit www.nei.nih.gov/glaucoma.

References:
Genetics of primary glaucoma. AO Khan. Current Opinion in Ophthalmology. 2011. 22(5):347-55

Julia Rosdahl - genetics and glaucomaJullia A. Rosdahl, MD, PhD
National Eye Health Education Program Glaucoma Subcommittee
Duke Eye Center, Duke University

Lasers for Glaucoma

7/10/14

Many people have heard of Laser Vision Correction, where special lasers are used to change the shape of the cornea to help a person see without the need for glasses or contact lenses. Lasers can also be used to treat glaucoma. There are different types of glaucoma, and they all can cause irreversible blindness; early diagnosis and treatments aimed at lowering eye pressure can help prevent blindness from glaucoma. Laser treatments for glaucoma do not improve vision, but they can help prevent vision loss.
Lasers for glaucoma
There are 3 main ways that lasers are used to treat glaucoma.

Laser Peripheral Iridotomy
Laser peripheral iridotomy involves making a hole in the iris, or colored part of the eye, to prevent angle closure glaucoma. Angle closure glaucoma happens when the drain of the eye is blocked by the iris. This type of glaucoma can come on very quickly, called “acute angle closure glaucoma”, or more slowly, called “chronic angle closure glaucoma”. When it comes on quickly, people will often have symptoms like eye pain and redness, blurry vision, and even nausea; the chronic form can have few or no symptoms. This laser can help prevent vision loss from angle closure glaucoma.

Laser Trabeculoplasty
Laser trabeculoplasty is used to treat open angle glaucoma. In open angle glaucoma, the drain of the eye is open, but not working well enough to keep the eye pressure controlled. During this procedure, the laser is focused on the drainage tissue itself (called the trabecular meshwork); it helps the drain to function better to lower the eye pressure. This laser procedure may be repeated after the effect wears off. This is not a cure for glaucoma; the disease still needs to be monitored regularly.

Gonio - lasers for glaucoma
Credit: Michael P. Kelly, FOPS Duke University Eye Center

Cyclophotocoagulation
Laser peripheral iridotomy and laser trabeculoplasty are both office-based procedures; cyclophotocoagulation, where lasers are used to treat the ciliary body (the part of the eye that makes the fluid), are frequently done in the operating room. Cyclophotocoagulation involves “coagulating” the ciliary body with a laser. After the procedure, the ciliary body makes less fluid, thereby lowering the eye pressure.

Laser treatments, along with eye medications and surgeries, are important components of the care of glaucoma patients. Early diagnosis and treatment can help prevent blindness from glaucoma. A comprehensive dilated eye exam by your eye care provider is the first step.

To learn more about glaucoma, visit www.nei.nih.gov/glaucoma.

Julia Rosdahl - lasers for glaucomaJullia A. Rosdahl, MD, PhD
National Eye Health Education Program Glaucoma Subcommittee
Duke Eye Center, Duke University