A cataract is an opacity or clouding of the eye’s crystalline lens. This lens is located just behind the coloured iris of the eyeball. As this lens clouding gradually progresses, you end up with the characteristic cataract symptoms of foggy vision, glare sensitivity, and reduced contrast vision. For some people, a developing cataract also causes other noticeable cataract symptoms such as altered colour perception or frequent changes to their prescription. Fortunately, cataract surgery is considered a highly effective and safe operation and is readily available via the Australian healthcare system.
While this is not an exhaustive list of every single factor that potentially causes cataracts, here are some of the most common cataract causes.
● Age. Older age definitely is at the top of the list of cataract causes. And because of our ageing population here in Australia, this also makes cataract surgery one of the most commonly performed surgical procedures. Exactly how increasing age causes cataracts is not fully understood, but doctors believe that the cumulative exposure of the eye to UV radiation over a lifetime may be at least partly to blame. Additionally, as we age, the crystalline lens continually grows more lens fibres around its outer layers. Over time this may compact the inner lens fibres and cause them to opacify.
● Diabetes and other metabolic diseases. A systemic condition such as diabetes causes cataracts due to the abnormal metabolism of certain compounds in the body, which can accumulate in the lens of the eye or affect the water content of the lens. For example, diabetes causes cataracts by elevated glucose levels inducing the lens to absorb more water and swell. This intake of water damages the lens fibres and causes them to become opaque.
It is estimated that people with diabetes are at a 60% higher risk of developing cataracts compared to someone without diabetes. Furthermore, because of the other effects of systemic diseases on the body and other parts of the eye, having a metabolic condition may make cataract surgery more complicated.
● Certain medications. Various medications, whether topical eye drops or systemic administration (such as via intravenous injection, inhaler, or oral tablets) may be associated with the development of a cataract. The risk of developing a cataract as a side effect of a medication is usually dependent on the dosage and duration of use of the drug. The most well-known of these are corticosteroids. A steroid-induced cataract often forms at the centre of the back surface of the lens, leading to significant cataract symptoms such as glare sensitivity and a decrease in vision. Unfortunately, once a steroid-induced cataract has formed, ceasing the steroid medication doesn’t reverse the cataract; only cataract surgery is able to treat it.
● Smoking. Tobacco use is also on the list of cataract causes and may accelerate your need for cataract surgery at an earlier age compared to a non-smoker. Smoking is also associated with an increased risk of various other eye diseases, including age-related macular degeneration. Unlike cataracts which can be treated with cataract surgery, the vision lost from macular degeneration is irreversible. Research tells us that a smoker is twice as likely to develop a cataract compared to someone who has never smoked. Those who are previous smokers but now no longer smoke are able to decrease their risk but unfortunately still carrya higher risk of developing a cataract compared to someone who has never smoked.
● Trauma. Types of trauma that are inducing a cataract are not limited to just an accidental hit to the eye. While a blunt blow such as a cricket ball has the potential to cause a cataract, radiation to the eye and electrocution may also result in cataract formation necessitating cataract surgery. Penetrating eye injuries such as a shard of glass through the eye from a car accident can also cause a cataract, as can chronic inflammation in the eye, such as from uveitis.
● Other systemic health conditions. Having hypertension or being obese is also linked with a higher risk of developing a cataract. Excess fat tissue when overweight releases a chemical into the bloodstream that causes oxidative damage to the eye. This causes the lens fibres to become hazy. Elevated blood pressure during hypertension is thought to cause inflammation throughout the body, which may also induce cataract formation. Studies have observed that hypertension is in fact the most frequent risk factor in patients attending for cataract
● Alcohol consumption. Alcohol intake and its effect on cataract formation is not fully understood as different studies have observed different findings. Many have noted that the risk of developing age-related cataract symptoms increases with an increasing level of alcohol consumption. However, some studies have also found that moderate alcohol consumption actually has a protective effect against cataract formation, decreasing the
likelihood of cataract surgery.
With the eye being such a complex and delicate organ, we are likely to discover more factors associated with causing a cataract as our medical understanding continues to progress. Fortunately, cataracts can be effectively treated through cataract surgery, often restoring your vision to pre- cataract days and even giving you clear vision without your old glasses!
Call us now on (03) 9070 3580 for a consultation.
Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second
opinion from an appropriately qualified health practitioner.