Steroids
Steroids exist in different forms, such as:
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Topical cream (treatment for eczema and psoriasis),
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Inhaled corticosteroids (treatment for hay fever and asthma) and
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Oral steroids (treatment for many inflammatory, allergic, immunologic, and malignant diseases)
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Ocular steroids (treatment for severe eye allergies and eye surgeries)
Among them, prolonged use of oral and ocular steroids can increase the risk of cataract.
Cataract
A cataract is the most common cause of treatable blindness around the world. It is characterised by lens opacity, i.e. the clouding of the normally clear lens of the eye.
Common symptoms of cataract include:
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Painless progressive blurring of vision
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Glare (car headlights, lamp or sunlight may appear too bright)
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Frequent eyeglass prescription changes
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Double vision in one eye
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Poor night vision
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Colours seem faded
Image credit: myhealth.gov.
Image shows a dense cataract, with an opaque lens behind the pupil.
Although cataract can be caused by ageing, cataract can also be caused by:
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Exposure to environmental agents (e.g. UV light, smoke, high blood sugar due to diabetes)
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Existing eye conditions such as trauma, uveitis, previous intraocular surgery
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Diseases (such as diabetes, hypocalcaemia, Down’s syndrome)
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Drugs such as ocular and oral steroids
How using steroids long-term can cause cataract?
The cataract caused by long-term use of steroids is usually bilateral, i.e. affect both eyes and develop slowly.
But how much and how long the steroids one takes to develop cataract? Well, although there is no minimum safe amount of steroids one can take with respect to the risk of developing a cataract, we know that the higher the dose of the steroids use and the longer the treatment duration, the greater the risk of cataract. It is more common with prednisone doses greater than 10 mg/day or with medications that have been administered for more than one year.
And of course, the risk of developing cataract is even higher if the patient is of older age.
In a study that evaluated 122 patients with RA taking a mean dose of prednisone of 8 mg/day for an average of 6.9 years, 29 percent developed cataracts compared with 18 percent of matched control.
What can you do to prevent cataract?
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If you’re taking steroids long-term, make sure you are taking it under the supervision of healthcare professionals.
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Do not use unregistered traditional and herbal medicines because there is a higher chance that they are adulterated with steroids. Taking these medicine long-term also means you might be ingesting a high dose of steroids unknowingly.
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Well balanced diet
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Regular exercise (helps in controlling blood sugar)
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If you are a diabetic, make sure your diabetes is well-controlled
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Protect your eye from UV light by using sunglasses with UV BLOCK.
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Protect your eye from injuries by using eye protective goggles when doing dangerous activities (hammering, handling chemicals, etc.)
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Attend eye screening with regularly to check your eye
Cover image credit: nvisioncenters
