Childhood Myopia: Understanding, Treating, and Slowing the Worldwide "Nearsightedness Epidemic"

Table of Contents

• Key Points
• Background: What Is Myopia and Why Does It Matter?
• Epidemiology: How Common Is Myopia Worldwide?
• Pathophysiology: What Causes Myopia in Children?
• Clinical Presentation and Complications: Beyond Wearing Glasses
• Ophthalmic and Pediatric Assessment: How Myopia Is Diagnosed
• The Genetics of Myopia: Multigenic and Syndromic Forms
• Myopia Control: Proven Strategies to Slow Progression
• Study Limitations: What the Research Could Not Prove
• Recommendations for Parents
• Frequently Asked Questions
• Source Information

Key Points

• Myopia is rising worldwide; by 2050, nearly 5 billion people are projected to be nearsighted.
• Myopia can lead to blinding complications like retinal detachment, glaucoma, and early cataract.
• Increasing outdoor time to 1–2 hours daily may reduce myopia onset; each extra hour weekly lowers risk about 2%.
• DIMS defocusing glasses and defocusing contact lenses reduced eyeball growth by about 52% in randomized trials.
• Low-dose atropine (0.01%) slowed myopia progression about 50% in the ATOM 2 study; stopping requires medical supervision.

Background: What Is Myopia and Why Does It Matter?

Myopia — commonly known as nearsightedness — is a refractive anomaly (a focusing error) of the eye that makes distant objects appear blurry. The name comes from the Greek words meaning "I close my eye," a reference to the squinting people often do to see better at a distance. The condition most often results from an increase in the axial length of the eyeball — meaning the eye grows too long from front to back.

When the eyeball is too long, the focal point of the image formed in the eye lands in front of the retina instead of directly on it, causing the object being observed to appear blurred. This is why people with myopia can see close objects clearly but struggle with distance vision.

Myopia is not just a simple vision problem. It is a global public health concern, primarily because the elongated eyeball can lead to potentially blinding complications, including retinal detachment, abnormal blood vessel growth in the retina (retinal neovessels), early cataract, and glaucoma. The objective of modern eye care is therefore to detect progressive myopia at an early stage in children and put in place "braking strategies" to limit the increase in the eyeball's length. Corrective glasses or contact lenses, of course, restore good vision — but they do not stop the underlying eye growth.

Epidemiology: How Common Is Myopia Worldwide?

Myopia is the most common sight disorder in the world, and its prevalence is exploding. According to the landmark study by Holden et al., published in the journal Ophthalmology in 2016, nearly 50% of the world's population is projected to be myopic by the year 2050.

Let's look at the exact numbers from that research:

• In 2000: approximately 1,406 million people worldwide were myopic (23% of the global population), with nearly 163 million classified as high myopes (2.7% of the population) — defined as requiring optical correction of less than -5 diopters (D).
• In 2050 (projected): the number is expected to reach 4,758 million myopes (49.8% of the population), including 938 million high myopes (9.8% of the population). In other words, nearly 5 billion people will be nearsighted.

The increase is particularly dramatic in Asian countries. In Singapore and Taiwan, myopia now affects up to 85–90% of young adults. In the United States and Europe, between 25% and 50% of older adults are myopic — still a very high proportion.

The epidemic of myopia in children and young adults is characterized by an increasingly earlier onset combined with high rates of disease progression. Several French expert reports conducted under the auspices of the National Agency for Accreditation and Health Evaluation (ANAES) and Inserm (the French National Institute of Health and Medical Research) have collected epidemiological data showing that in children under 6 years of age, 20% have visual anomalies, with refractive anomalies being the most frequent.

Beyond the health impact, myopia represents a major financial burden: the socio-economic cost has been estimated at 268 billion dollars per year worldwide. In Western countries, where the population is aging, myopia can decrease life expectancy and increase early loss of autonomy, making this a true public health priority.

Globally, the blinding complications of myopia also contribute to childhood blindness. In 2000, one child became blind every minute somewhere in the world — corresponding to 1.4 million blind children.

Pathophysiology: What Causes Myopia in Children?

The development of myopia involves multiple factors that result from a complex interaction between genetic predisposition and environmental exposure. Understanding this interaction is key to knowing how to prevent or slow the condition.

The Role of Visual Deprivation and Defocusing

During visual development, blurred vision of a certain type — as occurs in uncorrected myopia — produces an elongation of the eyeball (a process called "myopization"). In a myopic eye, the focal point of objects is located in front of the retina centrally because the eyeball is too long (myopic defocusing). However, at the periphery of the retina, the situation is different: the focal point is located behind the retina (hypermetropic defocusing).

This peripheral hypermetropic defocus is a key driver of myopia progression. The eye tries to compensate and "grow" to bring the peripheral image into focus, which leads to further elongation of the eyeball. Research in primates has shown that defocus at the retinal periphery induces axial myopia, whereas foveal (central) vision has less influence on the process of "emmetropization" — the eye's natural process of normalizing its refractive power during development.

Fresh evidence from electrophysiological studies in humans indicates that the retina actively participates in decoding defocused images by altering retinal ganglion cell signaling, confirming that peripheral vision plays a major role in driving eye growth.

Light and Dopamine

Among environmental factors, light stimulation — which varies according to wavelength — is probably one of the fundamental mechanisms of myopia onset and progression. When the retina is exposed to light, it releases dopamine, and dopaminergic agonists (substances that activate dopamine receptors) inhibit the increase in axial length. Outdoor light is rich in the wavelengths that stimulate this protective dopamine release.

Near Work and Screen Time

The onset of myopia may also be associated with increased near-vision activities, such as reading, studying, and screen use. Some studies show that students have a higher prevalence of myopia. Experimental studies have demonstrated that myopia can be triggered in animals wearing concave lenses that simulate near-vision work. It therefore seems likely that the increase in near-vision work during modern life has contributed significantly to the worldwide rise in myopia. Another suspected environmental factor is the type of light spectrum children are exposed to, with an ongoing scientific controversy over blue light and violet light.

Clinical Presentation and Complications: Beyond Wearing Glasses

Beyond the need for corrective lenses, myopia can cause complications that are sometimes severe and potentially blinding. This is why prevention is so important — to limit the development of myopia and prevent visual impairment in adulthood.

The ocular complications of myopia are partly a consequence of the elongation of the eyeball. As the eye stretches, the tissues at the back of the eye are placed under mechanical stress. The main complications include:

• Retinal detachment — the retina peels away from the back of the eye
• Myopic chorioretinal degeneration — thinning and deterioration of the retina and underlying choroid layer
• Subretinal neovascular complications — abnormal new blood vessels growing under the retina that can leak and scar
• Early cataract — clouding of the eye's natural lens at a younger age than usual
• Glaucoma — optic nerve damage often related to elevated pressure inside the eye

These complications of myopia are among the main causes of low vision and blindness worldwide. They become all the more frequent as the myopia becomes more severe (higher degrees of refractive error and longer axial length). The generation of low vision, or even blindness, justifies every effort to slow down myopic development in childhood.

Ophthalmic and Pediatric Assessment: How Myopia Is Diagnosed

Visual development in a child takes place in stages. Screening is carried out according to childhood health record recommendations in many countries, and a complete ophthalmological examination is performed if any anomaly is detected.

In children, it is important to identify the onset of myopia early — this is characterized by a refraction greater than -0.5 diopters combined with an increase in axial length. Myopia is considered progressive if it increases by -0.5D per year or more.

Diagnosis requires proper testing:

• Cycloplegia is imperative for diagnosis. This involves using eye drops that temporarily paralyze the internal and external muscles of the eye, allowing the eye to relax completely so an accurate measurement of its true refractive error can be obtained (without the child's natural focusing effort masking the degree of myopia).
• Optical biometry — measuring the axial length of the eyeball with a specialized device — is important for the initial assessment and for tracking the evolution of myopia over time.
• From the first verbal age (around 3–4 years old), a measurement of near and far visual acuity can be attempted using directional tests, drawings, and/or letters, using an object-matching method if necessary.
• In older children, visual acuity testing is essential for detecting refractive abnormalities such as myopia.
• Electrophysiological examinations (tests measuring the electrical activity of the visual system) can supplement the standard examinations and help identify retinal dystrophies or transmission problems in the visual pathways.

A warning note: data from prospective clinical trials suggest that undercorrection (prescribing weaker glasses than needed) either increases or has no effect on myopia progression. Myopic undercorrection should therefore not be recommended.

It is also essential to systematically rule out congenital glaucoma, especially when myopia is unilateral, since glaucoma initially causes an elongation of the eyeball in parallel with the increase in intraocular pressure.

The Genetics of Myopia: Multigenic and Syndromic Forms

Myopia presents multifactorial etiologies that remain incompletely understood. The genetic component has been proven in families with high myopia, in which specific genes have been described at locations 18p11.31, 12q21-31, and 7q36 on the human chromosomes. Some populations, such as Asian populations, appear to have a naturally myopic eye profile.

Recently, large-scale genome-wide association studies (GWAS) have attempted to identify the links between specific genes and the risk of myopia. Nearly 200 genes seem to be associated, alone or jointly, with myopia. This confirms that most ordinary myopia is polygenic — the result of many small genetic effects combining with environmental influences.

Syndromic Myopia: When Myopia Is a Sign of a Broader Condition

When faced with high or rapidly progressive myopia in a child, a pediatric and systemic assessment is crucial to look for associated pathologies and to diagnose any underlying syndrome. Many clinical syndromes have a genetic origin with Mendelian transmission (inherited according to classic dominant or recessive patterns), and the responsible genes have been identified.

Flitcroft et al., in a 2018 study published in Investigative Ophthalmology & Visual Science, analyzed genes involved in syndromic forms of myopia using the OMIM database (Online Mendelian Inheritance in Man) and identified the associated signaling pathways.

The most common syndromic myopias include (this is a non-exhaustive list):

• Stickler syndrome — a group of heterogeneous diseases with autosomal dominant inheritance affecting genes that encode different types of collagen (COL2A1, COL11A1, COL11A2, COL9A1, COL9A2, COL9A3). Prevalence is estimated between 1/7,500 and 1/9,000. It is characterized by high congenital (present at birth) but non-progressive myopia, vitreoretinopathy, retinal detachment, facial dysmorphism, deafness, hypermobile joints, and mitral valve prolapse.
• Wagner syndrome and related vitreoretinopathies — caused by VCAN gene mutations; features include myopia, optically empty vitreous, early cataract, night blindness with progressive chorioretinal atrophy, and retinal detachment.
• Hereditary retinal dystrophies including Congenital Stationary Night Blindness (CSNB) — with myopia, night blindness, nystagmus (involuntary eye movements), and strabismus.
• Marfan syndrome (FBN1 gene) — ectopia lentis (dislocated lens), myopia, aortic dilatation, skeletal anomalies, dural anomalies, and hyperelasticity.
• Weill-Marchesani syndrome (FBN1 gene) — ectopia lentis, microspherophakia (small spherical lens), glaucoma, short stature, brachydactyly (short fingers), and joint stiffness.
• Ehlers-Danlos syndrome — heterogeneous presentations with bluish scleral spots, joint hyperlaxity, and soft tissue fragility.
• Cohen syndrome (VPS13B gene) — progressive myopia, chorioretinal dystrophy, trunk obesity, growth retardation, hypotonia, psychomotor retardation, and neutropenia.
• Albinism (OCA2 and other genes) — skin and hair hypopigmentation, transilluminable iris, macular hypoplasia.
• Aniridia (PAX6 gene) — panocular involvement, absent or partial iris, limbal insufficiency, glaucoma, cataract, and macular hypoplasia.
• Knobloch syndrome (COL18A1 gene) — progressive high myopia, severe retinal detachment, occipital encephalocele, and psychomotor retardation.

This list is a diagnostic aid when a specific clinical association is found with myopia. The identification of a syndromic cause is vital because it guides medical management — both for the eyes and for the other organs involved.

Myopia Control: Proven Strategies to Slow Progression

The increase in myopia prevalence demands screening and — when myopia is progressive — active treatment. There are two complementary ways of controlling myopia: preventing its appearance in the first place, and reducing, preventing, or slowing down its progression once present.

A key principle unites many treatments: counteracting the sensory phenomenon of hypermetropic (far-sighted) defocus at the retinal periphery. By ensuring the best visual acuity through precise optical correction, and by altering how light focuses at the edges of the retina, it becomes possible to reduce the signal that drives further eyeball growth.

The main strategies with evidence behind them include: time spent outdoors, bifocal or defocusing corrective glasses, defocusing contact lenses, orthokeratology, and pharmacological treatments (low-dose atropine).

Time Outdoors: The Simplest Preventive Measure

Numerous studies have shown that increasing time spent outdoors and decreasing near-vision work can reduce the onset of myopia or delay it over time. Key data:

• In a cohort of 863 Australian children (average age 6 years), time spent outdoors was 16.3 hours per week for myopic children versus 21.0 hours per week for non-myopic children.
• A 2013 study in China with 681 children showed a lower prevalence of myopia associated with more time spent outdoors.
• A meta-analysis of 7 studies found that the probability of myopia was reduced by 2% per additional hour of outdoor time per week.

Outdoor time appears to work through several mechanisms — bright light stimulates retinal dopamine release, which inhibits excessive axial growth, and outdoor activities naturally reduce the time spent on near-vision tasks.

Bifocal, Progressive, and Defocusing Glasses

In the absence of robust randomized studies, the use of traditional corrective lenses — whether monofocal (single vision), bifocal, or progressive — has not demonstrated significant efficacy in slowing myopia progression. They restore vision but do not change the eye's growth pattern.

However, a new class of lenses has changed the picture. A recent randomized, double-blind study conducted over 2 years using DIMS lenses (Defocus Incorporated Multiple Segments), developed by Hoya Vision Care and the Polytechnic University of Hong Kong, showed remarkable results. In 79 children wearing these lenses versus 81 children wearing standard single-vision lenses, the variation in axial length was decreased by 0.55 mm — a 52% reduction in eyeball growth compared to the control group. Wearing defocusing corrective lenses can therefore be considered, potentially in combination with other treatments.

Defocusing Contact Lenses

Standard soft contact lenses and rigid gas-permeable lenses are not effective at delaying myopia progression. But the same principle of peripheral defocus can be applied to contact lenses. A randomized double-blind study of 53 patients wearing new soft defocusing lenses versus 56 control patients showed that the variation in axial length was reduced by 0.32 mm (a 52% reduction compared to the control group). This approach can also be combined with other treatments.

Orthokeratology (Ortho-K)

Orthokeratology involves applying compression to the cornea using a rigid lens of a particular geometry worn at night while sleeping. The lens temporarily flattens the radius of curvature of the cornea. In the morning, the lens is removed, and the patient typically needs no optical correction during the day.

The reduction of myopia — within the limit of about 6 diopters — is achieved by thinning of the central corneal epithelium, thickening of the mid-peripheral epithelium, and stromal changes. The cornea gradually returns to its original shape if the lenses are stopped.

Orthokeratology has shown an impact on myopia prevention, though randomized studies on large samples are lacking. It carries the risk of infection associated with any contact lens wear, and overnight wear reduces corneal oxygenation, so proper hygiene and monitoring are essential.

Pharmacological Treatment: Low-Dose Atropine

Daily instillation of atropine eye drops is one of the most powerful therapeutic options for slowing myopia. Atropine blocks muscarinic receptors in a non-selective manner. In humans, these receptors are present in the ciliary muscle of the eye, the retina, and the sclera (the tough outer coat of the eyeball).

Although the exact mechanism of atropine in controlling myopia is not fully known, it appears to act directly or indirectly on the retina or sclera, inhibiting scleral thinning or stretching and slowing eye growth.

How effective is it? Several meta-analyses suggest atropine eye drops provide the best efficacy of all myopia control methods.

The key clinical trial data come from two landmark studies conducted in Singapore:

• ATOM 1 (Atropine in the Treatment of Myopia), involving 400 children, used 1% atropine. It found good efficacy but significant side effects, including light sensitivity and blurred near vision, which affected children's quality of life.
• ATOM 2, also with 400 children, tested lower doses. The results showed a dose-dependent effect on myopia progression: -0.30 ± 0.60 D (with axial length change of 0.27 ± 0.25 mm) for the 0.5% dose; -0.38 ± 0.60 D (axial length 0.28 ± 0.28 mm) for 0.1%; and -0.49 ± 0.63 D (axial length 0.41 ± 0.32 mm) with 0.01% atropine.

At a dose of 0.01%, atropine offers an appropriate benefit/risk ratio: it achieves an overall 50% reduction in myopia progression without clinically significant visual side effects.

The LAMP study (Low-Concentration Atropine for Myopia Progression) was the first randomized, double-blind trial against placebo to provide solid evidence for low-concentration atropine. It compared 0.05%, 0.025%, and 0.01% concentrations and demonstrated a concentration-dependent response in both efficacy and side effect profile. The study suggested that 0.05% was the most effective concentration and remained well tolerated.

One caution: whatever the dosage used (0.01% or 0.05%), a rebound effect can occur when treatment is stopped — meaning the eye may start growing quickly again. Stopping should be planned carefully with an eye care professional.

Scleral Reinforcement Surgery

As the severity of myopia increases, excessive axial elongation exerts a biomechanical stretch on the posterior pole of the eyeball, followed by retinal complications that can lead to major visual impairment. For these severe cases, a surgical technique exists: posterior scleral reinforcement.

First proposed by Igor Shevelev in 1930, this surgery uses biological or non-biological materials to reinforce the weakened scleral area at the back of the eye and block further axial length elongation. The single-band surgical technique is recommended. The technique was modified in the 1970s, but it remains quite invasive and is generally reserved for very severe, rapidly progressive myopia at high risk of complications.

Study Limitations: What the Research Could Not Prove

While the evidence for myopia control is strong, it is important to understand the limits of the current research:

• Orthokeratology lacks large-scale randomized controlled studies, making its true long-term preventive effect difficult to quantify.
• Bifocal and progressive glasses have not shown significant efficacy in randomized trials, except for the newer DIMS defocusing lens designs.
• The atropine studies (ATOM 1 and ATOM 2) were conducted in Singapore, largely in Asian populations, and may not fully generalize to all ethnic groups. The optimal duration of treatment and the safest way to discontinue it to avoid rebound effects are still being investigated.
• Genetic studies have identified nearly 200 genes associated with myopia, but the interactions between these genes and environmental factors remain incompletely understood.
• The role of light spectrum (blue vs. violet light) in myopia development is still controversial, and definitive conclusions cannot yet be drawn.
• Most quoted statistics about the "myopia epidemic" are projections based on modeling; the actual trajectory could differ depending on environmental changes and the adoption of preventive measures worldwide.

Recommendations for Parents

Based on the current scientific evidence, here is practical advice for parents concerned about their child's vision:

1. Prioritize daily outdoor time. Aim for at least 1–2 hours of outdoor activity per day, even on cloudy days. Every additional hour per week reduces myopia risk by approximately 2%.
2. Limit near-vision screen time where possible, and encourage regular breaks that allow the eyes to look at distant objects.
3. Schedule regular eye examinations starting in early childhood, especially if there is a family history of myopia. Remember that accurate diagnosis requires cycloplegia (dilating eye drops) in children.
4. If myopia is diagnosed, ensure full and precise correction. Do not under-correct — this can actually accelerate progression. Ask your eye care professional about modern myopia control options.
5. Consider evidence-based treatments such as low-dose atropine (0.01% or 0.05%), DIMS defocusing glasses, defocusing contact lenses, or orthokeratology, depending on your child's age, maturity, and the severity of progression. Discuss the pros and cons — including side effects, costs, hygiene requirements, and the possibility of rebound after stopping — with your ophthalmologist.
6. For high myopia (worse than -5D) or rapidly progressing myopia (more than -0.5D per year), seek a thorough pediatric and genetic assessment to rule out syndromic forms such as Stickler or Marfan syndrome.
7. Monitor for complications. If your child is highly myopic, be alert to symptoms such as flashes of light, new floaters, or a curtain/shadow over vision, which could indicate retinal detachment — an emergency requiring immediate care.
8. Plan treatment discontinuation carefully. If using atropine, stop under medical supervision to manage potential rebound effects.

Myopia is not just about glasses — it's a lifelong eye health issue. But with early detection, modern treatment options, and consistent preventive habits, parents can genuinely slow their child's myopia and reduce their lifetime risk of serious complications.

Frequently Asked Questions

What is myopia and why is it serious in children?

Myopia, or nearsightedness, is a focusing error where the eyeball grows too long, making distant objects blurry. It matters because an elongated eye raises risks of retinal detachment, glaucoma, early cataract, and abnormal blood vessel growth. Slowing progression in childhood helps protect lifelong eye health, not just improve vision.

How is myopia diagnosed in a child?

Diagnosis requires a complete eye exam with cycloplegic eye drops to relax focusing muscles, plus optical biometry to measure eyeball length. Visual acuity testing is used in older children. Myopia is diagnosed at refraction greater than -0.5 diopters with increased axial length, and is considered progressive if it worsens by -0.5D per year.

What are the proven ways to slow myopia progression in children?

Proven strategies include increasing outdoor time, using DIMS defocusing glasses, defocusing contact lenses, orthokeratology, and low-dose atropine eye drops. In trials, DIMS lenses and defocusing contacts each reduced eyeball growth by about 52% compared with standard lenses. Atropine 0.01% reduced progression by about 50% with few side effects.

How effective is low-dose atropine for myopia control?

Low-dose atropine is one of the most effective myopia controls. In the ATOM 2 study of 400 children, 0.01% atropine slowed progression by about 50% without clinically significant visual side effects. The LAMP trial found 0.05% more effective but with a higher side-effect profile. Stopping can cause rebound, so discontinuation should be planned with an eye doctor.

What is orthokeratology and is it safe for children?

Orthokeratology uses specially shaped rigid lenses worn overnight to temporarily flatten the cornea, giving clear daytime vision without glasses. It can slow myopia, but large randomized studies are lacking. Risks include infection and reduced corneal oxygenation from overnight wear, so strict hygiene and regular monitoring are essential.

When should a child see a specialist for possible syndromic myopia?

If a child has high myopia (worse than -5 diopters), rapidly progressing myopia (more than -0.5D per year), or other signs like hearing loss, joint hypermobility, or facial differences, a pediatric and genetic assessment is crucial. Syndromes like Stickler, Marfan, or Wagner can be identified early, guiding treatment for eyes and other organs.

What are the warning signs of retinal detachment in a myopic child?

In a highly myopic child, watch for flashes of light, new floaters, or a curtain/shadow over vision. These can indicate retinal detachment, which is an emergency requiring immediate care. Myopia lengthens the eye and stresses the retina, raising detachment risk, so prompt evaluation is vital to preserve sight.

Should I get a second opinion before choosing a myopia control treatment like low-dose atropine or DIMS glasses for my child?

Childhood myopia can be slowed with several proven strategies, including low-dose atropine eye drops, DIMS defocusing glasses, defocusing contact lenses, and orthokeratology. Each carries different side effects, costs, hygiene requirements, and rebound risks after stopping. Because undercorrecting glasses can actually accelerate progression, a second opinion can ensure the diagnosis is accurate and that all appropriate treatment options are considered for your child's age and progression rate. Diagnostic Detectives Network provides independent expert second opinions.

Source Information

Original article title: Myopie de l’enfant ENG Childhood myopia

Author: Dominique Bremond-Gignac

Publication: médecine/sciences, vol. 36, August–September 2020, pages 763–768.

DOI: https://doi.org/10.1051/medsci/2020131

Author affiliation: Necker University Hospital Ophthalmology Department (APHP), OPHTARA Rare Disease Center, Paris; Faculty of Medicine, University of Paris; Inserm unit UMRS 1138, team 17, Paris Sorbonne Paris Cité University, France.

This patient-friendly article is based on peer-reviewed research published in a scientific journal. It is intended for educational purposes and does not replace professional medical advice. Always consult a qualified ophthalmologist for diagnosis and treatment of your child's vision problems.