Understanding the Causes of Glaucoma: What You Need to Know

Glaucoma is a serious eye condition that can lead to vision loss and blindness if left untreated. It is often associated with increased intraocular pressure (IOP), which can damage the optic nerve over time. While the exact cause of glaucoma isn’t always clear, several risk factors and underlying conditions contribute to its development. In this blog, we will explore the primary causes of glaucoma and what you can do to protect your vision.

1. Increased Intraocular Pressure (IOP)

One of the leading causes of glaucoma is elevated eye pressure. The eye constantly produces a fluid called aqueous humour, which drains through a mesh-like channel. When this drainage system becomes blocked or inefficient, fluid builds up, increasing pressure inside the eye. Over time, this elevated pressure can damage the optic nerve, leading to vision loss.

2. Genetics and family history

Glaucoma tends to run in families, suggesting a strong genetic component. If you have a family history of glaucoma, your risk of developing the condition increases. Certain genetic mutations have been linked to different types of glaucoma, such as primary open-angle glaucoma (POAG) and congenital glaucoma.

3. Age related changes

Age is a significant risk factor for glaucoma. Individuals over the age of 60 are at higher risk, as natural ageing processes can affect the efficiency of the eye’s drainage system. Older adults should have regular eye exams to monitor for signs of glaucoma.

4. Medical conditions

Certain medical conditions can increase the risk of developing glaucoma. These include:

• Diabetes – Can contribute to the development of neovascular glaucoma, where abnormal blood vessels grow and block fluid drainage.
• Hypertension (High blood pressure) – May impact blood flow to the optic nerve, making it more vulnerable to damage.
• Cardiovascular diseases – Can also affect the optic nerve’s health and function.

5. Eye injuries and trauma

Eye injuries, such as blunt force trauma or penetrating injuries, can lead to secondary glaucoma by disrupting the normal fluid drainage system. Even past injuries that seemed minor can result in delayed glaucoma development.

6. Prolonged use of corticosteroids

Long-term use of corticosteroids, especially in eye drop form, can increase intraocular pressure. Patients using these medications for conditions like asthma, arthritis, or skin disorders should have their eye pressure monitored regularly.

7. Thin corneas and optic nerve sensitivity

Some individuals are born with thinner corneas or more fragile optic nerves, making them more susceptible to damage from intraocular pressure fluctuations. Eye specialists can assess corneal thickness and nerve health during comprehensive eye exams.

8. Ethnic background

Certain ethnic groups have a higher risk of developing glaucoma. For example:

• Māori and Pasifika populations have been found to have a lower risk of glaucoma.
• Asian populations have a higher incidence of angle-closure glaucoma.
• African descent individuals are at a higher risk of developing primary open-angle glaucoma at a younger age and with greater severity.
• Hispanic/Latino individuals also face an increased risk as they age.

How to Reduce Your Risk

While some risk factors for glaucoma, such as age and genetics, are beyond your control, there are steps you can take to lower your risk:

• Get regular comprehensive eye exams to detect glaucoma early. The recommendation is every 5 years from 40, every 3 years from 50 and every two years from 60.
• Maintain a healthy lifestyle with a balanced diet and regular exercise.
• Manage underlying health conditions like diabetes and high blood pressure.
• Wear protective eyewear to prevent eye injuries.
• Follow your doctor’s advice on medication use, especially corticosteroids.

Conclusion

Glaucoma is a complex condition with multiple contributing factors. By understanding its causes and risk factors, you can take proactive steps to protect your vision. Regular eye exams and early detection are key to preventing significant vision loss. If you are concerned you are at risk for glaucoma, book a consultation with one of our Glaucoma specialists to develop a personalised eye health plan.