Roberts B1 Lingham G2,3 Mackey D1,2,4

1Tasmanian School of Medicine, 2Lions Eye Institute, 3Centre for Eye Research Australia, 4University of Western Australia Medical School, Centre for Ophthalmology and Visual Science

Biography:

To follow

Abstract:

Purpose

To synthesise the current literature regarding how the rate of myopia progression varies from summer to winter and how latitude and length of school holidays affect this rate.

Methods

A literature review was completed to identify papers published since 2002 that reported on the seasonal progression of myopia. Studies measured axial length (AL) or refractive error (RE) at either 3- or 6-month intervals and tracked the longitudinal change. Studies reporting on interventions such as orthokeratology were also included, as were those that included emmetropes and hyperopes.

Results

Four papers recorded a significant increase in RE change in winter compared to summer in myopes. Seven studies 5 in non-interventional trials and 2 in orthokeratology patients found that axial elongation was slower in summer as opposed to winter. One study (Fujiwara et al. 2012) demonstrated no difference in RE change between winter and summer but did confirm that axial elongation was slower in summer than winter. Four of 5 studies using general population data reported axial elongation was faster in winter than summer. No correlation between latitude and quantity of seasonal myopic change was identified. Based on limited data, it appears that the longer the summer school holiday period, the greater the change in AL or RE progression between summer and winter.

Conclusion

Progression of myopia slows in summer compared to winter in myopic and general population samples. Latitude does not appear to influence the rate of change; however, the length of summer school holidays may have an impact.