Cataracts: Leading Cause of Blindness and How to Reduce Your Risk.
About 2.2 billion people in the world have vision impairment or blindness.[1]
Cataract is the leading cause of blindness in adults worldwide, accounting for almost half of all cases in people who are 50 years or older.[2]
For context, if we take out 10 adults with blindness, at least 4 of them will be from cataracts.
As we can see from its global distribution, cataract knows no boundary, race, tribe or religion. Although adults are more often affected, children can have cataracts too.[3]
This article seeks to inform you of this common, worldwide disease that can cause blindness, and arm you with knowledge about its prevention and treatment, so you can take the right steps or inform others of what to do if and when you encounter it.
What is Cataract?
Definition.
Cataract is defined as “opacification of the normal crystalline lens of the eye”.
What does that mean?
Normally, the lens of the eye is a transparent structure that lets light pass through it, so we can see clearly.
In cataracts, the lens becomes cloudy. It loses its transparency. As a result, light can not pass through it. This causes vision impairment, and ultimately, blindness.
Types of Cataracts.
Cataracts can be grouped into various types based on age, the part of the lens affected, and whether the entire lens or only part of it is involved.
Based on age.
Congenital Cataracts — occurs early on after birth.
Juvenile cataracts — late childhood, and during the adolescent period.
Age-related cataracts — also known as senile cataracts. This is seen in older people.
Based on the part of the lens affected.
The lens has different parts. Capsule, cortex and nucleus are the major parts. Here, cataracts can be;
- Capsular
- Subcapsular
- Cortical
- Nuclear
Based on whether the entire lens or only a part is affected.
- Immature — the lens still has some transparent areas[4]
- Mature
- Hypermature
Causes of Cataracts?
Several factors can cause cataracts, including;
- Aging
- Trauma
- Diabetes
- Malnutrition
- Galactosemia
- Smoking
- Use of some medications, like steroids, over a long period.
- Exposure to ultraviolet rays
Of all the factors, aging is the most common cause of cataracts.
Signs and Symptoms of Cataracts.
Generally, the only symptom is impaired vision, and as it worsens, blindness. It could start as
- Blurring of vision
- Difficulty with night vision
- Poor colour vision
Treatment Options.
Currently, the only definitive treatment option is eye surgery. I’ll delve into cataract surgery in my next article. It is a safe procedure with high success rates, so there’s little to worry about.
But as usual, you will be informed of possible complications and side effects, even though the likelihood of them occurring is minimal.
Some cataracts that are not fully mature benefit from glasses. This doesn’t prevent the progression to a mature cataract, but it improves vision for the time being.
The aim of cataract surgery is to improve vision significantly, so if the difference between that gotten from surgery and that from the use of glasses isn’t much, the surgery may be delayed until a time when the patient will benefit a great deal.
Complications of cataracts.
What happens if you don’t remove cataracts?
Vision worsens progressively, ultimately leading to blindness.
How to prevent Cataracts.
First, you must know this truth. When it comes to cataracts, prevention is not as simple as saying “X causes cataracts, so if I avoid X, I will not have cataracts”.
There are a lot of factors involved, aging is one of them. Therefore, to the best of our current knowledge in the medical profession, we can only try to reduce the risks, but can not guarantee that an individual will not have cataracts by following all the rules.
Some things that can reduce the risks of cataracts;
- Avoid smoking
- Minimise eye exposure to UV rays from sunlight (wear shades)
- Adequate blood glucose control in people with diabetes
- Dietary supplementation with antioxidants and carotenoids have been shown to aid eye nutrition. Although this doesn’t prevent cataracts, it may reduce the risks.[5]
Conclusion.
In conclusion, cataract is a common eye disease worldwide. Aging is the most implicated factor. It is treated by cataract surgery, but in early stages, vision can be improved with glasses while waiting for a time when the patient will benefit significantly from cataract surgery.
Remember to always check in with a qualified healthcare service provider whenever you notice symptoms. Early detection and intervention go a long way in managing any condition well.
References.
1. World report on vision by the World Health Organization
https://www.who.int/publications/i/item/9789241516570
Accessed on Saturday 23rd December, 2023.
2. Steinmetz JD, Bourne RR, Briant PS, Flaxman SR, Taylor HR, Jonas JB, Abdoli AA, Abrha WA, Abualhasan A, Abu-Gharbieh EG, Adal TG. Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study. The Lancet Global Health. 2021 Feb 1;9(2):e144–60.
3. Foster A, Gilbert C. Epidemiology of childhood blindness. Eye. 1992 Mar;6(2):173–6.)
4. Vaughan & Asbury’s General Ophthalmology EIGHTEENTH EDITION. Page 174.
5. Fernandez MM, Afshari NA. Nutrition and the prevention of cataracts. Current opinion in ophthalmology. 2008 Jan 1;19(1):66–70.
