The National Eye Institute (NEI) defines glaucoma as "a group of diseases that can damage the eye's optic nerve and result in vision loss and blindness." There are four types of glaucoma: low-tension or normal-tension glaucoma, congenital glaucoma, angle closure glaucoma and secondary glaucoma. According to the NEI, anyone can develop glaucoma though it is five times more likely to affect African Americans than Caucasians and is also more likely to occur in those with a family of glaucoma. There are a number of risk factors or causes of glaucoma.
Familial Factors
According to "The Eye Digest,"glaucoma tends to run in families although details about the role of genetics in the development of glaucoma is not yet clear. However a 1998 research paper published in "Archives of Opthalmology," found that the prevalence of glaucoma was 10.4 percent in siblings of patients with glaucoma and 1.1 percent in offspring of patients with the condition. Lead author, D.P. Dimasi, notes that patients with relatives who have glaucoma have an increased risk of glaucoma. However, the author added that further studies were needed solidify the heredity link between family members and glaucoma.
Drugs
The University of Maryland Medical Center cites a number of drugs that may cause glaucoma. Closed-angle glaucoma may result from use of medications such as antihistamines, tricyclic antidepressants prescribed for anxiety and depression such as amoxapine, and asthma medications like nebulized ipratropium. The anti-seizure drug, topiramate, which is used to treat epilepsy may also cause closed-angle glaucoma. Steroids, such as oral and topical corticosteroids may cause secondary glaucoma. According to the University of Maryland Medical Center, patients using topical steroid treatments in the eye are at the highest risk of glaucoma.
Disease
Individuals with conditions such as diabetes, migraine and high blood pressure may be at a higher risk for glaucoma, according to the University of Maryland Medical Center. The Glaucoma Research Foundation estimates that people with diabetes are twice as likely to develop glaucoma than people who do not have diabetes. High blood pressure may cause glaucoma because it increases internal eye pressure also known as intraocular pressure (IOP). However, the link between IOP and glaucoma is not conclusive. In a 2004 interview published by the Glaucoma Service Foundation, Dr. Elliot Werner, a glaucoma specialist, indicates that research on the relationship between glaucoma and blood pressure and glaucoma is unclear.
References
- NEI: Facts About Glaucoma
- The Eye Digest: Glaucoma causes Optic Nerve Cupping (atrophy) and Vision Loss
- Archives of Opthalmology: Genetic risk of primary open-angle glaucoma. Population-based familial aggregation study
- University of Maryland Medical Center: Glaucoma - Causes
- Glaucoma Research Institute: Diabetes and Your Eyesight
