Why Do Eye Prescriptions Change in Adults?

An increase in eye prescription during adulthood is usually caused by long hours of screen use, age-related lens changes, genetic factors, or systemic conditions like diabetes. Although refractive errors are expected to stabilize in your early twenties once eye development is complete, intense close-up work and environmental factors can lead to the progression of myopia or astigmatism. Constantly focusing on digital devices, in particular, causes spasms and fatigue in the eye muscles, directly impacting your visual quality.

At a Glance:

• While changing eye prescriptions in adulthood are relatively uncommon, they can increase with heavy screen exposure.
• Myopia progression is often caused by the stress of focusing on close objects for extended periods.
• An increase in astigmatism is related to age or disease-related changes in the structure of the cornea.
• Conditions like diabetes and pregnancy can lead to temporary or permanent prescription changes.
• Regular eye exams ensure the early detection of underlying diseases like cataracts or glaucoma.

What Causes Vision Changes in Adulthood?

The growth and development of the eyeball typically stop in the early twenties. After this period, the degrees of refractive errors known as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (blurred and distorted vision) are expected to remain stable. However, some individuals may experience changes in their eye prescriptions despite advancing age. In medical terms, this is called adult-onset refractive error progression.

Vision deterioration stems from subtle changes in the anatomical structure of the eye. While myopia progression in childhood is usually related to the elongation of the eyeball on the front-to-back axis, changes in adults are more closely linked to the loss of flexibility in the eye's lens, changes in the corneal curvature, or extreme fatigue of the intraocular muscles. Especially for people who work in office environments and spend most of their day looking at computer or phone screens, the eye's ability to accommodate is strained, paving the way for pseudomyopia or an increase in their current prescription.

Causes and Risk Factors

Changing eye prescriptions in adults are not tied to a single cause; they emerge from a combination of environmental factors, lifestyle, and systemic health conditions. Digital eye strain is one of the most common culprits. A reduced blink rate while looking at screens and the constant need for eye muscles to focus up close are significant risk factors for myopia progression.

Additionally, blood sugar fluctuations directly affect eye health. In diabetic patients, high blood sugar causes the lens inside the eye to absorb fluid and swell. This swelling changes the angle of light refraction, leading to temporary or permanent myopic shifts. Hormonal fluctuations during pregnancy can also cause slight changes in corneal thickness and shape, resulting in an increase in astigmatism or a shift toward myopia.

Another crucial factor that emerges with advancing age is the onset of cataracts. Nuclear cataracts, characterized by the hardening of the center of the eye's lens, increase the eye's refractive power. This can cause a person's distance vision to blur while their near vision becomes clearer than before. Although this phenomenon is colloquially known as "second sight," it is actually a symptom of disease. To learn more about the stages of cataracts and treatment methods, you can review our article titled Cataract Symptoms and Laser Cataract Surgery.

Symptoms

The signs that your eye prescription is worsening usually appear slowly and insidiously. In the early stages, your eyes try to tolerate this change, but complaints become more noticeable over time. The most common symptom is that distances you previously saw clearly now appear blurry. Struggling to read subtitles while watching television, noticing traffic signs late while driving, or seeing halos around lights during night driving (night myopia) are typical indicators.

When there is an increase in astigmatism, the edges of objects may begin to look shadowed or double. The eyes constantly struggle to focus in order to obtain a clear image. This excessive effort leads to intense headaches concentrated in the forehead and temple areas, as well as burning, stinging, and watering in the eyes. You may start squinting involuntarily to see clearly. Furthermore, extreme fatigue in the eye muscles can lead to involuntary spasms in the eyelids. If you would like to learn the detailed causes of such spasms, you can check out our content Why Does Eye Twitching Occur, Is It Dangerous?.

How is it Diagnosed at the Hospital?

A definitive diagnosis of a change in eye prescription is made through a comprehensive eye examination. When you visit the hospital, your doctor will first ask about your medical history, daily lifestyle habits, and the amount of time you spend in front of screens. Then, a standard visual acuity test is administered. This test, where you are asked to read letters or symbols, determines the degree of your current vision loss.

Next, the refractive error of the eye is measured objectively using an autorefractor. Following this measurement, a device called a phoropter is used to try different lenses, subjectively determining the prescription that provides the clearest and most comfortable vision for you. Your eye doctor will also thoroughly examine the anterior segment of the eye, the cornea, and the lens using a biomicroscopy (slit lamp) examination.

If astigmatism is increasing rapidly and irregularly, a corneal topography test is requested to map the cornea. This test is critical for ruling out a serious disease called keratoconus, which is characterized by the thinning and bulging of the cornea. Finally, the pupil is dilated with drops to perform a retina and optic nerve examination. This allows for the early detection of underlying issues such as diabetic retinopathy or macular degeneration that might be causing the prescription increase.

Treatments and Ways to Stop Prescription Progression

When an increase in an adult's eye prescription is detected, the first step is prescribing the correct glasses or contact lenses to improve visual quality and relieve eye strain. Updating your glasses prescription resolves the spasms in your eye muscles, quickly eliminating complaints like headaches and focusing difficulties. If your eye prescription has remained stable for the last year, laser eye surgeries like LASIK or PRK may also be considered as a permanent treatment option, provided your doctor deems it appropriate.

Alongside medical treatment, simple precautions you take at home and at work can significantly reduce the risk of myopia progression. Applying the 20-20-20 rule while working at a screen is highly effective: Every 20 minutes, rest your eye muscles by looking at an object 20 feet (about 6 meters) away for 20 seconds. Ensure your computer screen is slightly below eye level and that there is a distance of at least 50-60 centimeters between you and the monitor. Additionally, maintaining adequate ambient lighting and preventing screen glare are important steps in alleviating digital eye strain.

Complications and Risk Groups

An excessive increase in eye prescription, particularly in the degree of myopia (high myopia), means the eyeball has elongated more than normal. Adults with high myopia are at a high risk for complications that can lead to severe vision loss, such as retinal tears, retinal detachment, glaucoma (high eye pressure), and myopic macular degeneration. As the eyeball elongates, the retinal layer thins and becomes more vulnerable to mechanical stress.

Diabetic patients represent another significant risk group who experience constant prescription changes due to uncontrolled blood sugar. Individuals with a family history of high myopia, keratoconus, or early-onset cataracts have a higher genetic predisposition. It is vital for people in these risk groups not to dismiss changes in their prescriptions as mere fatigue and to undergo regular eye screenings before complications develop.

When to See a Doctor?

Slow changes in your eye prescription can be monitored during routine exams. However, certain symptoms may be harbingers of a more serious underlying eye disease and require you to consult an ophthalmologist without delay. Be sure to seek medical evaluation if you notice the following warning signs:

• Sudden blurriness or dark areas in your vision,
• Experiencing flashes of light or lightning streaks in front of your eyes,
• A sudden appearance of numerous black dots or floaters in your field of vision,
• Seeing objects as double or distorted,
• Severe eye pain, redness, and extreme sensitivity to light.

If you experience sudden and total vision loss, if a chemical substance splashes into your eye, or if you receive a severe direct blow to the eye, these situations require emergency medical intervention. In such a scenario, you should immediately call the 112 emergency line or visit the nearest hospital's emergency room without waiting.

Your Eye Health Journey at BHT CLINIC

Accurate diagnosis and treatment methods are of paramount importance to protect your eye health and maximize your visual quality. In our Ophthalmology (Eye Diseases) department, we provide services with our experienced medical staff and advanced diagnostic equipment. When you visit us with complaints of changing eye prescriptions, your detailed refractive error measurements, corneal topography, and retinal scans are performed meticulously.

Bringing your old glasses, contact lens information, and previous eye exam reports with you when you come to our hospital ensures a more accurate analysis of the rate of your prescription change. In cases of emergency eye trauma or sudden vision loss, our 24/7 emergency department and on-call teams are ready for immediate intervention. To avoid delaying your eye health and to create the most suitable treatment plan for you, you can book an appointment.

Frequently Asked Questions

Can myopia progress after the age of 30?

Yes, it can. Although eye development stops in your twenties, an increase in the degree of myopia can still occur after the age of 30 due to heavy screen use, close-up work, or systemic diseases like diabetes.

Does astigmatism go away on its own?

Astigmatism is a structural condition caused by an irregular shape of the cornea or lens. Therefore, it is not expected to go away or correct itself on its own. Glasses, contact lenses, or laser treatments in suitable patients are required to improve visual quality.

Do phone and computer screens ruin your eyes?

Screens do not directly ruin your eyes or cause permanent damage; however, prolonged use leads to digital eye strain. A reduced blink rate and constant close-up focusing tire the eye muscles, which can trigger a temporary or permanent increase in your prescription.

Does not wearing glasses make your prescription worse?

In adults, not wearing glasses does not directly increase your eye prescription. However, when glasses are not used, your eyes exert excessive effort to see clearly. This situation leads to severe headaches, eye strain, and focusing issues.

Why does eye prescription change during pregnancy?

Hormonal changes and fluid retention experienced during pregnancy can slightly alter the thickness and curvature of the cornea. This can cause a temporary myopic shift or an increase in astigmatism; it usually returns to normal after childbirth and the end of the breastfeeding period.

This article is for informational purposes only; please consult your physician for diagnosis and treatment.