MR ALEX BANEKE - OPHTHALMIC SURGEON - GLAUCOMA & CATARACT
A Guide for Patients
Understanding Glaucoma Risk Factors:
"Why me?"
If you’ve been diagnosed with glaucoma, you might be wondering, "Why me?". It's a common question. While certain causes like steroid use, trauma, or previous eye surgery are known, the reasons behind the most common type, primary open angle glaucoma, are not fully understood. However, we do know that glaucoma is a multifactorial disease, meaning there are various risk factors that can predispose someone to developing it. This page will help you understand these risk factors and how they may apply to you.
Understanding the risk factors for glaucoma can help you take proactive steps in managing your eye health. Whether it’s monitoring your blood pressure, making healthy lifestyle choices, or ensuring regular eye tests, being aware of these risks is the first step in protecting your vision. If you have a family history of glaucoma or other risk factors, talk to your eye specialist about how you can best manage your eye health.
The Bigger Picture
Glaucoma is the leading cause of irreversible blindness worldwide. In the UK, about 2% of people over 40 have glaucoma, but it’s estimated that more than 50% of cases go undiagnosed. This means that for every person who knows they have glaucoma, there is likely another who has it but doesn’t know. In England alone, around 480,000 people have primary open angle glaucoma. The condition is more common in older adults, with 1 in 50 people over 40 and 1 in 10 people over 75 affected.
What Are the Risk Factors for Glaucoma?
Risk factors for glaucoma have been identified through years of observing people with the disease. These factors can be classified into two categories: modifiable and non-modifiable.
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Modifiable Risk Factors: These are risk factors you can change or control, such as managing high blood pressure.
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Non-Modifiable Risk Factors: These include things you cannot change, like your age or family history.
Elevated Eye Pressure
​Most types of glaucoma are associated with high eye pressure. However, some people develop optic nerve damage from glaucoma even with normal eye pressure, a condition known as normal tension glaucoma. Currently, all glaucoma treatments focus on lowering eye pressure because it’s the only risk factor we fully understand and can manage effectively.
High Blood Pressure
The relationship between blood pressure and glaucoma is complex. Some studies suggest that high blood pressure can slightly increase eye pressure, while others indicate that low blood pressure, especially at night, might contribute to glaucoma. A sensible approach is to maintain blood pressure within a normal range and avoid extremes. If you’re on blood pressure-lowering medication, it’s important to inform your eye doctor, as adjustments to your medication might be necessary.
Diet and Lifestyle
While diet isn’t thought to have a significant impact on glaucoma, there’s some evidence that vitamin B3 (nicotinamide) might slow disease progression. Its found in red meat, poultry, fish, brown rice, nuts, seeds, legumes and bananas.
However, there isn’t enough evidence yet for doctors to recommend it universally. Eating a healthy, varied diet and getting regular exercise are always good for overall health. Some patients, particularly those with pigment dispersion syndrome, should avoid high-impact sports, as these can increase the risk of pressure spikes in the eyes.
Other Risk Factors
Age
Glaucoma can affect people of all ages, but it’s most common in those in their 70s and 80s. As we age, the optic nerve gradually loses nerve cells, and glaucoma accelerates this process. The longer we live, the greater the risk of developing glaucoma.
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Ethnic Origin
People of African or Caribbean descent are at higher risk of developing glaucoma, often at a younger age and with more severe disease. This risk increases significantly after age 40.
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Family History of Glaucoma
Glaucoma, particularly primary open angle glaucoma and primary angle closure glaucoma, often runs in families. If you have a close relative with glaucoma, your risk of developing the disease is four to nine times higher than average.
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Myopia (Short-Sightedness)
Moderate to high short-sightedness increases the risk of developing certain types of glaucoma, especially pigmentary glaucoma and primary open angle glaucoma.
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Hypermetropia (Long-Sightedness)
Long-sightedness can lead to primary angle closure glaucoma, as these eyes are often smaller, which can crowd the drainage system and lead to increased pressure.
Implications for Your Family
Glaucoma is often a painless condition that damages the outer edges of vision first, gradually working its way inwards. Because it progresses silently, many people don’t realise they have it until it’s advanced. Early detection through regular sight tests with an optician is crucial.
While everyone should have an eye test every two years, those with a close relative (parent, sibling, or child) with glaucoma should be tested more frequently. In the UK, people over 40 with a first-degree relative who has glaucoma are eligible for free sight tests every two years.
