A cataract refers to a clouding of the lens. Cataracts are most commonly associated with advancing age. They usually occur in the 40s or 50s, but visual problems may not manifest until much later. Understanding what causes cataracts allows you to either prevent this disease or take proper treatments.
According to National Eye Institute, a cataract is a cloudy area in the lens of your eye. Cataracts are very common as you get older. Cataracts can make your vision blurry, hazy, or less colorful. You may have trouble reading or doing other everyday activities.
Types of Cataracts:
Nuclear cataracts damage the lens’s center. Initially, a nuclear cataract may induce increased nearsightedness or even a transient improvement in reading vision. However, as time passes, the lens becomes more thickly yellow, obscuring your eyesight even more. The lens may even become brown as the cataract advances. Advanced lens yellowing or browning can make it difficult to discriminate between different tones of color.
Cortical cataracts impair the lens’s edges. The first signs of a cortical cataract are white, wedge-shaped opacities or streaks on the lens cortex’s outer border. The streaks gradually expand to the center of the lens, interfering with light flowing through the center.
Posterior subcapsular cataracts impair the lens’s rear surface. A posterior subcapsular cataract begins as a tiny, opaque patch near the rear of the lens, directly in the light path. It can create glare or halos surrounding lights at night, interfere with reading vision, and impair vision in bright light. These forms of cataracts develop more quickly than others.
Congenital cataracts are what you are born with. Some people are born with cataracts, while others get them when they are children. These cataracts might be hereditary, or they could be the result of an intrauterine illness or trauma
The etiology of cataracts – in other words, what actually causes them to form – usually involves a combination of the following factors, rather than a single isolated cause:
Water and protein make up the majority of the eyes. Some of the protein may develop pieces and fog a specific part of the eye lens as we become older. It has the potential to expand over time, resulting in partial or full vision loss.
According to a recent study, long-term exposure to sunshine increases the risk of cataracts. There is a link between UV light and oxidative stress. The latter is a process that occurs over time and is a primary cause of aging and the illnesses such as cataracts. Long-term exposure to sunlight increases the formation of specific compounds in the lens, which can lead to vision difficulties.
Our eyes’ lenses get nutrients from the aqueous humor, including oxygen and glucose. Diabetes patients do not have complete control over their blood glucose levels. Sugar levels in the aqueous humor may rise as a result. This can cause swelling and impair eyesight at the same time. Similarly, an enzyme in the lens of the eye turns glucose into sorbitol. This sugar alcohol has the potential to harm both cells and proteins, resulting in cataracts.
Hypertension has been linked to increased inflammation, leading to cataracts. It also causes changes in the proteins in our eyes’ lenses. This causes hazy vision, which can eventually lead to visual loss. It can cause age-related macular degeneration and glaucoma, in addition to cataracts.
Smokers have a larger risk of developing cataracts than nonsmokers. Toxins in cigarette smoke promote cell oxidation, which includes cells in the eye lens. Heavy smoking causes more than only cataracts. It also causes a multitude of eye health issues, which eventually lead to eyesight loss. Smokers are more likely to develop age-related macular degeneration. The retina is damaged by AMD, which makes reading and driving difficult.
Prolonged use of corticosteroid medications – including steroid eye drops, oral steroids, and even high-dose inhaled steroids used for conditions like asthma – is a well-established risk factor for cataracts, particularly the posterior subcapsular type. If you’re on long-term steroid treatment for any condition, it’s worth discussing regular eye monitoring with your doctor rather than stopping the medication on your own.
Trauma to the eye, past eye inflammation (such as uveitis), or previous eye surgery can all increase the likelihood of developing a cataract, sometimes appearing years after the original injury or procedure.
A family history of cataracts, particularly at a younger age, may increase your own risk, suggesting a genetic component in some cases. Obesity has also been identified by the NEI as a risk factor, though the exact mechanism isn’t fully understood.
Cataract risk is cumulative and multifactorial – it usually comes down to a combination of age, genetics, health conditions like diabetes, and lifestyle factors like sun exposure and smoking, rather than any single cause. Two people of the same age can have quite different risk profiles depending on this mix of factors.
The clinical manifestations of cataract – the symptoms a patient notices, alongside the signs a doctor observes on examination – typically develop gradually rather than suddenly. Patient-reported symptoms usually come first, and often include progressively blurred or hazy vision, increased glare or light sensitivity, and difficulty seeing at night. On clinical examination, a doctor may observe lens opacity (cloudiness) using a slit lamp, and in advanced cases, the pupil itself may appear pale grey rather than black, a sign sometimes referred to as leukocoria. The specific pattern of symptoms can also vary somewhat depending on the type and location of the cataract – for example, posterior subcapsular cataracts tend to cause glare and reading difficulty relatively early, while nuclear cataracts may initially cause a temporary shift in near vision before progressively clouding overall eyesight.
Initially, the cloudiness caused by a cataract may only impact a tiny portion of your vision, and you may be completely unaware of any vision loss. The cataract swells in size, clouding more of your lens and distorting the light traveling through it. It’s possible that this will result in more obvious symptoms. Signs of cataracts include:
Left untreated, cataracts tend to worsen gradually, progressively clouding more of the lens and increasingly affecting daily activities like reading, driving, or recognising faces. In advanced, long-untreated cases, cataracts can lead to significant vision impairment or blindness. The encouraging news is that cataracts are highly treatable – surgery is generally very effective at restoring clear vision, and there’s no need to wait until a cataract severely affects your daily life before discussing treatment options with a doctor.
Cataract surgery is to get your clouded lens replaced. If your cataracts are impacting your vision and quality of life, surgery is typically offered on the NHS.
Following cataract surgery, it can bring some benefits: perceive things clearly, look into bright lights and distinguish the difference between colors. However, after successful surgery, if you have another eye illness, such as diabetes or glaucoma, you may still have reduced vision.
You’ll be sent to a professional eye doctor for an evaluation before surgery. Various measures of your eyes and vision will be obtained throughout the examination. The evaluation provides an opportunity to talk about everything related to your operation, including your preferred lens type (near-sighted or far-sighted), the advantages and disadvantages of surgery, and how long it will take you to fully recover if you require glasses following the surgery.
It’s possible that you’ll be told not to eat or drink anything for 12 hours before your cataract surgery. Your doctor may also urge you to cease taking any medications that might raise your risk of bleeding during the operation for a short period of time. If you take any medications for prostate issues, tell your doctor since some of these medications might interfere with cataract surgery. One or two days before surgery, antibiotic eye drops may be recommended.
Cataract surgery is a simple operation that takes 30 to 45 minutes to complete.
To dilate your pupil, your doctor will first insert eye drops in your eye. You’ll receive local anesthetics to numb the area and a sedative that helps you relax. The sedative will make you be awake but sleepy during surgery.
The clouded lens is removed during cataract surgery, and a clear prosthetic lens is generally put in its place. However, in rare circumstances, a cataract can be eliminated without implanting an artificial lens.
While not all cataracts can be prevented – particularly those linked to ageing or genetics – a few habits may help reduce your risk or slow their progression:
Most commonly, ageing-related protein changes in the eye’s lens, along with risk factors like UV exposure, diabetes, smoking, long-term steroid use, previous eye injury or surgery, and family history.
Blurry or hazy vision, increased light sensitivity or glare, halos around lights, difficulty seeing at night, and faded colour perception.
Yes – long-term use of corticosteroid medications, including steroid eye drops, oral steroids, and high-dose inhaled steroids, is a well-established risk factor.
Not entirely, especially age-related cataracts, but UV protection, not smoking, and managing conditions like diabetes may help reduce your risk.
Cataracts tend to progressively worsen and can lead to significant vision impairment or blindness if left untreated long-term, though they’re highly treatable with surgery.
Cataracts are a common, well-understood part of aging for many people, but they’re also influenced by a range of other factors – from UV exposure and diabetes to long-term steroid use and eye injuries – that are worth understanding, since some are within your control. Recognising the early symptoms and getting regular eye exams means cataracts can typically be caught and treated well before they seriously affect your daily life. If you’re noticing changes in your vision, you can consult a doctor through the MaNaDr app to discuss your symptoms and whether a referral to an eye specialist is the right next step.
