Adult myopia progression, and how to treat it

The majority of myopia appears and progresses during childhood, and most children with myopia are expected to stabilize by the age of 18 years.1

Hence, myopia control should ideally continue until the end of high school, and through tertiary study (i.e. university) as well before stopping treatment.

Onset of childhood myopia commonly occurs between 8 and 13 years of age.2 Myopia progression typically begins to stabilize during adolescence, with studies indicating that around half (48%) of myopic children reach stability by 15 years of age.3

Meanwhile, the remaining half of teenagers will continue to experience myopia progression into late adolescence and early adulthood. Based on the COMET data, over 50% of children will continue to progress at 15 years, nearly 25% at 18 years, and 10% at 21 years.3 By 24 years of age, 96% of myopes could be considered to have stable myopia.

Both adult myopia progression and adult-onset myopia are common among adults aged 18 to 25 years of age.

The likelihood of adult myopia progression declines with age. 

Bullimore et al. found that significant myopia progression (≥−1.00 D over 5 years) occurred in roughly 20% of young myopic adults aged between 20−40 wearing soft contact lenses.7 Progression was more common among myopic individuals in their 20s (20−35%) but still occurred among those in their 30s (>10%).

Table 1: The rate of myopia progression in different age groups (at baseline) and the sample as a whole.7

Progression is especially common among college and university students undertaking intensive programs such as optometry, medicine, and law. In fact, the vast majority of studies in young adults aged <25 years have been conducted in university cohorts.

Across studies of myopia progression in adults aged 18 to 25 years, the proportion of myopic adults who progressed by ≥0.50 D range over several years range from 32−55%. For myopia progression in adults aged 25 to 40 years, proportion of adults progressing by ≥0.50 D is reportedly between 16−49%.

Adults in non-university populations can also experience myopia progression, although the rates appear to be slower. For example, in a Finnish longitudinal study spanning 23 years, the 10-year myopia progression was −0.41 D. In 45% of cases, progression was ≥−0.50 D and in 18% of cases, myopia increased by ≥−1.00 D.8

Adult myopia progression usually occurs at a slower rate compared to childhood/juvenile-onset myopia, and is limited to a smaller proportion of individuals. 

The annual rate of axial elongation in myopic adults aged 18 to 25 years is 0.05−0.1 mm/year, with an average of 0.07mm/year. Evidence from longitudinal studies suggest that juvenile, adolescent, and adult myopia progression are all primarily the result of axial elongation.1

The annual rate of progression in myopic adults aged 18 to 25 years varies between −0.1 and −0.2 D/year, with an average of −0.14 D/year, according to the IMI.1 Myopia progression among adults aged 25 to 40 years is slower, with an annual progression of less than −0.1 D/year.

Research on the risk factors associated with adult myopia onset and progression is scarce.

In 2021, the IMI published a report on the risk factors for myopia, but did not distinguish between the risk factors for children versus those in adults.9 Subsequently in 2023, the IMI published a paper on onset and progression of myopia in young adults, and identified a number of potential associations.1

These include:

• Younger age
• Parental history of myopia
• Female gender
• East Asian ethnicity
• Lower choroidal thickness
• University study
• Outdoor activity
• Contact lens material or design

An Australian birth cohort study reported on myopia onset in adults aged 20 years at baseline and 28 years at follow-up.10 Incident myopia was associated with East Asian race, female gender, smaller conjunctival ultraviolet autofluorescence (CUVAF) area, and parental myopia. Interestingly, smaller CUVAFs indicate less sun exposure and suggests less time spent outdoors.

Even without a strong evidence base, adults who demonstrate myopia progression can still be considered as candidates for myopia control. 

While myopia progression may be more modest in adults, the benefits of myopia management can outweigh the risks. Every dioptre saved reduces an individual’s risk of eye disease and visual impairment later in life.

Here’s what to consider when managing the adult myope.

Several myopia control interventions have proven effective in children, but these treatments have not yet been evaluated in adults. Future studies involving adults is unlikely due to are practical and methodological barriers. 

It’s important to communicate to the patient that while myopia control strategies may work, it is difficult to predict their efficacy. 

Consider that adults have competing demands such as work, study, or family responsibilities, that can reduce compliance and increase loss to follow-up.

Given that all myopic individuals need vision correction, prescribing an optical treatment that can both correct and control myopia should be considered. 

The logical first-line choice would be contact lens-based options, especially orthokeratology. Orthokeratology is likely to be well-accepted by adults as it can provide good high contrast visual acuity and spectacle independence, and small studies have also reported stabilizing effects on myopia in adults.11,12

Treatments that are well-accepted in children may be tolerated differently in adults. 

Young adults have higher visual demands than children (e.g. driving and screen-based work) and might not be as tolerant as children to myopia control spectacle or soft contact lens designs. 

For atropine, dose-dependent efficacy must be balanced with side effects on vision and accommodation. Compliance may also be a challenge as atropine does not provide any vision correction.

Remember that myopia can continue to progress in young adults, even in those who appear stable. 

Ongoing monitoring through regular refraction and ocular health examinations is the standard of care. 

Annual retinal examination (with dilated fundus assessment on indication) is recommended, and even more important for those with high myopia and/or axial length >26 mm. 

Axial length measurement (where available) can provide a valuable indicator of pathology risk.

• Myopia progression is relatively common in young adults, with around 20% of adults progressing at least 1.00 D. Those in their 20s are more likely to progress than those in their 30s.
• Contact lens wear is likely the best first-line choice for adult myopia control, as it is a dual correction and control strategy, and likely to be very well accepted by this patient group.
• Continue to monitor eye health annually with dilated fundus examination (where indicated), even if the patient’s myopia is stable. Higher myopes and those with axial lengths over 26 mm warrant greater caution.