Galveston County Daily News May 7, 2013
Medical Discovery News
By Drs. David Niesel and Norbert Herzog
Today, 2.7 million Americans over the age of 40 are suffering from an eye disease that slowly robs them of their sight. About half of them don’t even know they have this disorder, despite the fact that a comprehensive eye exam will easily detect it. While there is still no cure for glaucoma, a new study shows that statins, a class of drugs commonly used to lower cholesterol, might actually prevent it.
Glaucoma usually occurs when the pressure of the fluid in the eye slowly increases, eventually damaging the optic nerve. The optic nerve is actually a bundle of nerves that carries information from the eye’s retina to the brain, where images are interpreted. The fluid in the eye, called the aqueous humor, circulates around inside the eye. This fluid provides nourishment to parts of the eye that do not have blood vessels and maintains the appropriate pressure inside the eye, both of which are keys to normal vision. A small amount of the fluid is produced every day while an equal amount flows out. With glaucoma, the fluid does not leave the eye as it should, and pressure on the eye gradually increases as fluid accumulates.
A nationwide study by the University of Michigan School of Medicine found that statins like Lipitor and Zocor can lower the risk of developing glaucoma. The largest study ever done on this topic followed 300,000 people aged 60 and over who were diagnosed with hyperlipidemia, or high levels of unhealthy fats called lipids. By taking statins continuously for two years, the subjects reduced their risk of developing the most common kind of glaucoma by almost 10 percent.
The most common type of glaucoma, called primary open-angle glaucoma, is caused by not enough fluid drainage. Other types of glaucoma can be caused by the iris blocking the eye’s fluid from draining, inheriting genes for the disease, injury to the eye, tumors, or even steroids. Treatment for glaucoma depends on the type of glaucoma, its severity and its response to treatment. Medicated eye drops can either increase the drainage of the fluid or reduce its production. Several types of surgery and laser treatments can improve the fluid drainage. Medical marijuana can reduce pressure on the eye, but only for a short time; it is not a recommended treatment.
For the millions of the people already taking statins, the study revealed a surprising added benefit. Leaders of the study do not yet know why statins have this effect, but think it may be due to the drug increasing blood flow to the optic nerve and retinal nerve cells and pushing out extra fluid, alleviating pressure in the eye.
Annual eye exams are a good addition to a yearly physical, especially for those most at risk for glaucoma: blacks, Hispanics, seniors, those with diabetes and those with a family history of the disease. The damage caused by glaucoma is irreversible, so prevention and early detection are currently the best way to combat the disease.
Medical Discovery News is a weekly radio and print broadcast highlighting medical and scientific breakthroughs hosted by professor emeritus, Norbert Herzog, and professor, David Niesel, biomedical scientists at the University of Texas Medical Branch at Galveston. Learn more at www.medicaldiscoverynews.com.