Progressive Myopia: Epidemiology, Aetiology, and Management Strategies

Sadat Yazdouni

Introduction

Myopia, or nearsightedness, affects approximately 30% of the global population, with rates predicted to rise to 50% by 2050. Progressive myopia, defined as a myopic shift of at least −0.50 dioptres (D) per year, poses significant challenges due to its association with axial elongation of the eye and increased risk of ocular morbidity(1). Understanding the aetiology and implementing effective interventions are essential to curbing its prevalence and impact.

Epidemiology

The prevalence of myopia varies geographically, with East Asia exhibiting rates exceeding 90% in young adults, compared to lower rates in Europe and North America(1). Urbanisation, increased educational demands, and reduced outdoor activity have been implicated in this trend. Children who develop myopia at an early age are particularly at risk of progression to high myopia (≤−6.00 D)(2), underscoring the importance of early detection.

Aetiology and Pathophysiology

Progressive myopia arises from a complex interplay of genetic and environmental factors. Genetic predisposition plays a significant role, with over 200 loci identified as contributing to myopic development (3). Environmental factors such as prolonged near work, insufficient exposure to natural light, and urban living conditions exacerbate the risk. Axial elongation, the hallmark of progressive myopia, results from dysregulated scleral remodelling and mechanical stress on retinal structures(4).

Emerging research has suggested a potential link between gestational diabetes mellitus (GDM) and the development of progressive myopia in offspring(5). GDM, characterised by hyperglycaemia during pregnancy, may influence fetal ocular development through mechanisms such as altered insulin-like growth factor (IGF) signalling and oxidative stress. Elevated IGF-1 levels in utero have been associated with increased axial length(6), while hyperglycaemia-induced oxidative stress may disrupt scleral remodelling, predisposing the eye to elongation(7).

Management Strategies

  1. Optical Interventions
    1. Orthokeratology (Ortho-K): Specialised rigid gas-permeable contact lenses worn overnight temporarily reshape the cornea, flattening the central curvature and creating peripheral myopic defocus. This mechanism reduces hyperopic defocus in the peripheral retina, which is thought to be a key driver of axial elongation. Studies show a reduction in axial elongation rates by up to 43% in children wearing Ortho-K lenses (8).
    1. Multifocal and Peripheral Defocus Contact Lenses: These lenses incorporate concentric zones of varying power, inducing peripheral myopic defocus while correcting central vision. The defocus modulates retinal signalling pathways involved in eye growth, slowing axial elongation. Randomised controlled trials report a 30-50% reduction in myopic progression with these lenses(9)
  2. Pharmacological Approaches
    1. Atropine Eye Drops: Atropine, a non-selective muscarinic receptor antagonist, is believed to inhibit excessive scleral remodelling by downregulating pathways involved in retinal dopamine signalling. Low-dose atropine (0.01%-0.05%) minimises side effects such as pupil dilation and accommodation loss while effectively reducing progression by 50-60%(10). Mechanistic studies suggest atropine also influences choroidal thickening and scleral collagen synthesis (11).
  3. Environmental Modifications
    1. Increased Outdoor Time: Natural light exposure is hypothesised to stimulate retinal dopamine release, which acts as an inhibitor of axial elongation. Clinical studies indicate that children spending over two hours outdoors daily exhibit a significantly lower incidence of myopia onset and progression (12).
    1. Reduction of Near Work: Prolonged near work increases ciliary muscle strain and hyperopic defocus, both contributors to axial elongation. Introducing structured breaks, such as the “20-20-20 rule,” mitigates these effects .
  4. Emerging Technologies
    1. Myopia Control Spectacles: Spectacles employing defocus-incorporated multiple segments (DIMS) or highly aspherical lenslets (HAL) generate peripheral myopic defocus while maintaining central vision. These innovations reduce axial elongation rates by 50-60% (13).
    1. Genetic and Molecular Therapies: Advances in CRISPR technology and molecular biology may allow targeted modulation of genes associated with myopic development, offering future therapeutic potential (14).

Complications and Long-Term Implications

High myopia significantly increases the risk of pathologies such as:

  • Retinal Detachment: Due to thinning of the retina and increased vitreoretinal traction (15).
  • Myopic Maculopathy: Progressive damage to the macula leading to irreversible vision loss (15).
  • Glaucoma: Higher susceptibility attributed to structural changes in the optic nerve (15).

Conclusion

Progressive myopia is a multifaceted condition requiring a multidisciplinary approach for effective management. Early intervention, leveraging optical, pharmacological, and behavioural strategies, is critical to mitigating its impact. Ongoing research into genetic and environmental mechanisms holds promise for innovative therapies. Public health initiatives promoting outdoor activities and education about myopia management are essential in addressing this escalating global challenge.

References

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2.        Saxena R, Dhiman R, Gupta V, Phuljhele S, Mahajan A, Rakheja V, et al. Prevention and management of childhood progressive myopia: National consensus guidelines. Indian J Ophthalmol [Internet]. 2023 Jul 1 [cited 2025 Jan 17];71(7):2873–81. Available from: https://journals.lww.com/ijo/fulltext/2023/71070/prevention_and_management_of_childhood_progressive.42.aspx

3.        Tedja MS, Haarman AEG, Meester-Smoor MA, Kaprio J, Mackey DA, Guggenheim JA, et al. IMI – Myopia Genetics Report. Invest Ophthalmol Vis Sci. 2019 Feb 28;60(3):M89–105.

4.        Pugazhendhi S, Ambati B, Hunter AA. Pathogenesis and Prevention of Worsening Axial Elongation in Pathological Myopia. Clin Ophthalmol [Internet]. 2020 [cited 2025 Jan 17];14:853. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC7092688/

5.        Du J, Li J, Liu X, Liu H, Obel C, Shen H, et al. Association of maternal diabetes during pregnancy with high refractive error in offspring: a nationwide population-based cohort study. Diabetologia [Internet]. 2021 Nov 1 [cited 2025 Jan 17];64(11):2466–77. Available from: https://link.springer.com/article/10.1007/s00125-021-05526-z

6.        Adzura S, Muhaya M, Normalina M, Zaleha AM, Ezat WPS, Tajunisah I, et al. Correlation of serum insulin like growth factor-I with retinopathy in Malaysian pregnant diabetics. Int J Ophthalmol [Internet]. 2011 [cited 2025 Jan 17];4(1):69–72. Available from: https://ies.ijo.cn/gjyken/article/abstract/201101016

7.        Du J, Li J, Liu X, Liu H, Obel C, Shen H, et al. Association of maternal diabetes during pregnancy with high refractive error in offspring: a nationwide population-based cohort study. Diabetologia [Internet]. 2021 Nov 1 [cited 2025 Jan 17];64(11):2466–77. Available from: https://link.springer.com/article/10.1007/s00125-021-05526-z

8.        Cho P, Cheung SW. Retardation of Myopia in Orthokeratology (ROMIO) Study: A 2-Year Randomized Clinical Trial. Invest Ophthalmol Vis Sci. 2012 Oct 1;53(11):7077–85.

9.        Erdinest N, London N, Lavy I, Berkow D, Landau D, Morad Y, et al. Peripheral Defocus and Myopia Management: A Mini-Review. Korean J Ophthalmol [Internet]. 2023 Feb 1 [cited 2025 Jan 17];37(1):70. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9935061/

10.     Wang Z, Li T, Zuo X, Zhang T, Liu L, Zhou C, et al. 0.01% Atropine Eye Drops in Children With Myopia and Intermittent Exotropia: The AMIXT Randomized Clinical Trial. JAMA Ophthalmol [Internet]. 2024 Aug 1 [cited 2025 Jan 17];142(8):722–30. Available from: https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2820256

11.      Kobia-Acquah E, Lingham G, Flitcroft DI, Loughman J. Two-year changes of macular choroidal thickness in response to 0.01% atropine eye drops: Results from the myopia outcome study of atropine in children (MOSAIC) clinical trial. Acta Ophthalmol [Internet]. 2024 [cited 2025 Jan 17]; Available from: https://onlinelibrary.wiley.com/doi/full/10.1111/aos.17429

12.     Dhakal R, Lawrenson JG, Huntjens B, Shah R, Verkicharla PK. Light exposure profiles differ between myopes and non-myopes outside school hours. BMJ Open Ophthalmol [Internet]. 2024 May 29 [cited 2025 Jan 17];9(1):1469. Available from: https://bmjophth.bmj.com/content/9/1/e001469

13.     Lam CSY, Tang WC, Tse DYY, Lee RPK, Chun RKM, Hasegawa K, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. British Journal of Ophthalmology [Internet]. 2020 Mar 1 [cited 2025 Jan 17];104(3):363–8. Available from: https://bjo.bmj.com/content/104/3/363

14.     Tedja MS, Wojciechowski R, Hysi PG, Eriksson N, Furlotte NA, Verhoeven VJM, et al. Genome-wide association meta-analysis highlights light-induced signaling as a driver for refractive error. Nature Genetics 2018 50:6 [Internet]. 2018 May 28 [cited 2025 Jan 17];50(6):834–48. Available from: https://www.nature.com/articles/s41588-018-0127-7

15.     Du Y, Meng J, He W, Qi J, Lu Y, Zhu X. Complications of high myopia: An update from clinical manifestations to underlying mechanisms. Advances in Ophthalmology Practice and Research. 2024 Aug 1;4(3):156–63.

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