The difficulty in identifying fast-progressing myopes based on prior progression

Paper title: The Limited Value of Prior Change in Predicting Future Progression of Juvenile-onset Myopia

Authors: Mutti, Donald O. OD, PhD, FAAO (1), Sinnott, Loraine T. PhD (1), Brennan, Noel A. MScOptom, PhD, FAAO (2), Cheng, Xu MD, PhD (1), Zadnik, Karla OD, PhD, FAAO (1)

1. The Ohio State University College of Optometry, Columbus, Ohio
2. Johnson & Johnson Vision, Jacksonville, Florida

Date: May 2022

Reference:  Mutti DO, Sinnott LT, Brennan NA, Cheng X, Zadnik K; Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study Group. The Limited Value of Prior Change in Predicting Future Progression of Juvenile-onset Myopia. Optom Vis Sci. 2022 May 1;99(5):424-433 [Link to open access paper]

The CLEERE study aimed to expand on the findings from the SCORM study¹ by including examination of axial length and a wider range of children's ages to establish predictive models for future myopia.

Matsumura et al¹ found that 1-year myopic progression had more influence on subsequent 2-year progression for young children than the baseline SER or the age of myopia onset.  Fast changes in the first year were associated with fast progression in the following 2^nd and 3^rd years, especially for younger children.  They did, however, discuss the limited ability of using annual myopia progression as a single predictive element for future myopia and suggested yearly monitoring to detect fast progression.

This study modelled future refractive error and axial length changes over at least 3 consecutive visits for 916 ethnically diverse children aged between 7 and 14yrs. Spherical equivalent refractive error (SER) was measured by cycloplegic auto-refraction (mean of 10 measures) and axial length by A-scan ultrasound (mean of 5 measures). Parents provided information regarding the children's sex, race/ethnicity and time the children spent outdoors or reading. Models for predicting refractive error were tested against the real data.

An average change of -0.54D SER and 0.26mm axial elongation was found between visits 1 and 2.  Between visits 2 and 3, these changes had both slowed with age to -0.36D and 0.19mm, respectively.

The difference between the actual and predicted changes were 0.22D and 0.14mm (without prior change) compared with 0.26D and 0.16mm with prior change, indicating the limited predictive value of the prior-progression model. Change in SER was correlated with prior change in SER, but the same was not found for axial length.

Parental myopia, time spent outdoors or reading were not found to be associated with subsequent myopia progression, but age, ethnicity and higher myopia were associated with future refractive error and axial length. Asian American children in the study were more likely to be more myopic with longer axial lengths than other ethnicities featured. Females had a more myopic SER, but being female did not predict axial length changes.

Prediction modelling using prior SER and axial length progression had limited impact on accuracy of the model, compared to the real data. Predicting future myopic progression was found to be more accurate when factors such as age, sex and ethnicity were considered, rather than just prior progression.

Myopia management should be initiated when myopia is apparent regardless of prior progression, rather than waiting to assess the progression rate.

Myopia control should be initiated based on the demographic factors of age, ethnicity and baseline values of SER and/or axial length, as these may be more accurate and simple indicators of a faster progressor than the single factor of previous refractive or axial changes.

While there is a relationship between prior observed and future predicted myopia progression, the variance explained by past progression is low, meaning it can be hard to predict which children will be faster or slower progressors. Hence, beginning myopia control early avoids a 'watch and see' approach where a child may then progress quickly and treatment opportunity is delayed.

Previously, the CLEERE study group found that near work was not a predictive factor for the onset of myopia or for progression. Time outdoors, however, limited the risk of onset of myopia even if it had little effect on further progression.^2-4  Parental myopia conversely increased the risk of myopia,^3,4 while also being unrelated to progression.⁵

• Myopia progression and axial length growth may be more accurately estimated using factors such as age, sex, ethnicity and baseline biometric values
• Since a full picture of myopia progression is seen over several years, further studies will confirm the influence of these factors over periods of time longer than 1 year.

Title: The Limited Value of Prior Change in Predicting Future Progression of Juvenile-onset Myopia

Authors: Donald O Mutti, Loarine T Sinnott, Noel A Brennan, Xu Cheng, Karla Zadnik

Purpose: This study aimed to develop models predicting future refractive error and axial length using children's baseline data and history of myopia progression and axial elongation.

Methods: Models predicting refractive error and axial length were created using randomly assigned training and test data sets from 916 myopic participants in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study. Subjects were 7 to 14 years of age at study entry with three consecutive annual visits that included cycloplegic A-scan ultrasound and autorefraction. The effect of adding prior change in axial length and refractive error was evaluated for each model.

Results: Age, ethnicity, and greater myopia were significant predictors of future refractive error and axial length, whereas prior progression or elongation, near work, time outdoors, and parental myopia were not. The 95% limits for the difference between actual and predicted change were ±0.22 D and ±0.14 mm without prior change data compared with ±0.26 D and ±0.16 mm with prior change data. Sensitivity and specificity for identifying fast progressors were between 60.8 and 63.2%, respectively, when the cut points were close to the sample average. Positive predictive value and sample yield were even lower when the cut points were more extreme.

Conclusions: Young, more myopic Asian American children in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study were the most likely to progress rapidly. Clinical trials should expect average progression rates that reflect sample demographics and may have difficulty recruiting generalizable samples that progress faster than that average. Knowing progression or elongation history does not seem to help the clinical decision regarding initiating myopia control.

[Link to open access paper]