Glaucoma : Losing sight of a global crisis?
The week of March 6 to 12, 2022, is being observed as World Glaucoma Week, a global initiative of World Glaucoma Association to raise awareness about an ailment that blinded 3.6 million people worldwide in 2020 alone. This World Glaucoma Week, Kruxd looks at the numbers behind this vision impairment.
By Bhargavi Saikia · Mar 08, 2022
More than 1.1 billion people across the globe live with some form of vision loss. 90 per cent of these cases are preventable or treatable. However, if not detected and treated properly at an early stage, they might result in irreversible vision loss or blindness.
According to the International Agency for the Prevention of Blindness (IAPB) data of 2020, 43 million people are blind worldwide. Out of this, glaucoma is reported to be blinding around 3.6 million people worldwide, thus being the third most common cause of blindness, after cataract and refractive disorders.
What is glaucoma, and why does it happen?
The eyes have a fluid called aqueous humor flowing inside them, cleansing them, and draining out through the trabecular meshwork - a tissue in the eye chamber. In glaucoma, either too much fluid is produced or it is not efficiently drained. The fluid accumulates and causes pressure to rise inside the eye, resulting in optic nerve damage.
Chances of one getting affected by glaucoma depend on a variety of factors, including family history, age, injury and pre-existing conditions, like very severe nearsightedness, injury to the eye, high blood pressure, existing cardiovascular ailments, and use of corticosteroid medicines.
Numbers continue to rise
Blindness due to glaucoma has been on the rise globally. Since 2010, the number of people with moderate to severe vision impairment is reportedly higher than that of total blindness. But, this cannot be regarded as something encouraging. These people with moderate to severe visual impairment have a high risk of becoming blind if they do not receive effective treatment and care.
The high-incidence regions
More than two-thirds of the people suffering from glaucoma-induced blindness in 2020 are from low and middle-income countries. This includes countries from South Asia, Southeast Asia, East Asia and Oceania. These regions, home to over 50 per cent of the world's population, make up for 33.3 per cent of the global numbers.
Looking at the picture of Asia and mainly its four regions - Central Asia, East Asia, South Asia and Southeast Asia, it is observed that South Asia tops the list with the highest number of blindness due to glaucoma. It accounted for over half a million cases of glaucoma-induced blindness and nearly a million cases of moderate to severe vision impairment in 2020. It is closely followed by East Asia and Southeast Asia with 0.5 million and 0.2 million blind cases respectively.
Does age and gender matter in those affected?
Vision impairment and blindness can affect people of all ages. Majority of those affected, however, are over the age of 50 years. Glaucoma has been the leading cause of blindness in the 70-79-years age group, with 1.1 million people affected.
In addition to this, global numbers for glaucoma-induced blindness have significantly increased from 1990 to 2020, with a 60.99 per cent increase among males and a 62.64 per cent increase among females.
A look at the number of ophthalmologists worldwide
A critical issue towards combating glaucoma is the lack of trained ophthalmologists. Estimates suggest there are 238,653 ophthalmologists in 191 countries in the world. Median numbers on ophthalmologists per million population reveal the extent to which Asia and Sub - Saharan Africa lag behind.
While efforts have been made to reduce the prevalence of blindness, major drawbacks in reducing the prevalence of blindness include population growth, with an increasingly aging population, as well as a lack of a comprehensive eye care approach.
As population and aging are closely associated with glaucoma, the number of people affected will increase over time considering the fast pace of the world’s demographic transition.
Both blindness and visual impairment are considered to be significant public health problems across the world, therefore it is important to have strategic plans to curtail the increasing burden of glaucoma blindness. Despite the fact that glaucoma control and prevention has now become a global concern, there is a significant absence of advocacy objectives, plans of action, or strategies in the context of glaucoma control.