Glaucoma: The silent thief of sight

BY SYLVESTER OJENAGBON

Glaucoma is a leading cause of blindness globally, especially in developing countries. In 2020, it was said to be the cause of blindness in about 3.61 million people, representing 8.4% of all blindness cases. In addition, glaucoma caused moderate and severe vision impairment in about 4.14 million people, which is 1.4% of all moderate and severe vision impairment cases. 

Figures from the World Health Organisation indicate that the global prevalence of glaucoma is estimated to be 3.54%, with the highest numbers in Africa. This means approximately 80 million people worldwide live with glaucoma. This number is expected to increase to 111.8 million by 2040.

Now, glaucoma is a group of eye diseases that damage the optic nerve, which carries visual information from the eye to the brain. This damage can lead to gradual loss of vision, possibly leading to irreversible blindness if not effectively managed. Although there is no cure for glaucoma, early diagnosis and treatment can slow the progression of vision loss and help protect vision. 

Four types of glaucoma are easily identifiable: open-angle glaucoma, angle-closure glaucoma, congenital glaucoma, and secondary glaucoma. Open-angle glaucoma is the most common type and is characterised by slow, gradual vision loss. 

Angle closure glaucoma is less common but can cause sudden and severe vision loss if not treated promptly. Congenital glaucoma is present at birth, often due to abnormal eye development. And secondary glaucoma develops as a result of another underlying condition, such as diabetes or a tumour. 

The biggest risk for developing glaucoma is high pressure in the eye. This risk of developing glaucoma increases with age, starting after 40, and more significantly after 60. Having a family history of glaucoma also increases your chances of having it. Certain genes have similarly been identified that can increase the risk of developing glaucoma. 

In addition, underlying medical conditions like diabetes, high blood pressure, and certain eye diseases can raise the risk of glaucoma. Previous eye injuries or certain types of eye surgery can sometimes lead to glaucoma. Long-term use of corticosteroids, especially as eye drops, can likewise increase the risk of secondary glaucoma. 

Having thinner-than-normal corneas can also increase the risk of developing glaucoma. Certain eye conditions like pigmentary dispersion syndrome or uveitis can equally contribute to glaucoma. Sadly, Black, Hispanic, and Asian people may have a higher risk of developing glaucoma.

In Nigeria, approximately 5% of the population is said to have glaucoma and around 0.7% of blindness in the country is attributed to the disease. A significant portion of glaucoma cases in the country is primary open-angle glaucoma. Unfortunately, a substantial number of individuals with glaucoma in Nigeria are either undiagnosed or untreated. 

The truth is that various factors contribute to the low utilisation of available resources for glaucoma detection and treatment in Nigeria. For example, many people are not aware of glaucoma or its symptoms. This leads to delayed diagnosis and treatment. Limited communication and education about the disease further worsen the problem. 

Also, the high cost of glaucoma treatment, including medication and surgery, can be a major barrier for many Nigerians. Even with public funding initiatives, the coverage and accessibility of these schemes are often limited. 

In addition, Nigeria faces a shortage of specialised eye care professionals and facilities, particularly in rural areas. The lack of proper equipment and diagnostic tools in many hospitals further limits the capacity to diagnose and manage glaucoma effectively. 

Furthermore, gender disparities, low education levels, and unemployment can limit access to information and healthcare resources. Poverty can equally lead to a lack of resources for healthcare, making it difficult to seek and adhere to treatment plans. Poor patient compliance with medication regimens and follow-up appointments can undermine the effectiveness of treatment. 

Research has shown that some patients may refuse glaucoma surgery, even when it is the recommended treatment. Concerns about the risks and potential complications of surgery, as well as a lack of understanding of the benefits, often contribute to this reluctance.

Now, glaucoma usually progresses without noticeable symptoms in the early stages, making regular eye examinations critical for early detection. It is recommended that people at higher risk get comprehensive dilated eye examinations every 1 to 2 years, as early detection and treatment can help control the disease and prevent further vision loss. 

Acute angle-closure glaucoma is a medical emergency that requires immediate treatment to prevent blindness. Its symptoms include headache; blurred vision; sudden, severe eye pain; and nausea. Anyone experiencing these symptoms must therefore seek medical care without delay. 

Maintaining a healthy lifestyle, including not smoking, regular exercise, and a balanced diet, can help reduce the risk of developing certain conditions that can contribute to glaucoma. 

If you have a family history of glaucoma or are at higher risk, you need to talk to your doctor about your risk factors and how often you should get checked. 

To be on the safe side, it is important that we are all aware of the importance of eye health and seek medical care when necessary. And if you have concerns about your eyes or vision, there is no better time than now to contact your doctor or ophthalmologist. Any further delay may lead to serious, avoidable consequences.

Ojenagbon, a health communication expert and certified management trainer and consultant, lives in Lagos.